Post on 01-Jan-2017
SET - Production Processes and Efficiency Measures
Overview of textile production processes and energy efficiency measures for machineries,
technologies and equipment researched on by the SET project team to develop an Energy
Saving and Efficiency Tool (ESET)
Leading author: CITEVE
Date: December 2014
Table of contents
Table of contents .................................................................................................................... 2
Acknowledgments .................................................................................................................. 3
1 – Executive summary ......................................................................................................... 4
2 - Introduction ....................................................................................................................... 5
3 - Textile production processes ....................................................................................... 7
4 - Energy in the textile industry.................................................................................... 11
4.1 - Energy use in yarn production, main factors affecting energy consumption and
reference values ...................................................................................................................... 12
4.2 - Energy use in fabric production, main factors affecting energy consumption and
reference values ...................................................................................................................... 14
4.3 - Energy use in finishing, main factors affecting energy consumption and reference
values ...................................................................................................................................... 16
5 - Energy efficiency measures ....................................................................................... 21
5.1 - Energy efficiency measures for Yarn Production process ............................................... 23
5.2 - Energy efficiency measures for Fabric Production process ............................................ 26
5.3 - Energy efficiency measures for Finishing process........................................................... 28
5.4 - Cross-cutting energy efficiency measures ...................................................................... 44
6 – Conclusions and Next Steps ....................................................................................... 72
7 - Reference .......................................................................................................................... 73
SET – Production Processes and Efficiency Measures
www.euratex.eu/set 3/73
Disclaimer The sole responsibility for the content of this publication lies with the authors. It does not
necessarily reflect the opinion of the European Union or of any of the organization
mentionedunless explicitly stated. Neither the EASME nor the European Commission are
responsible for any use that may be made of the information contained therein.
This document is updated until December 2014, however contents are simplifield and
provided for general information purposes only. By no mean the contents provided in this
document shall be considred exausitve.
Legal and or official documentation released at EU level or the national legislation shall be
consulted.
Acknowledgments
The SET project (contract n° IEE/13/557/SI2.675575) is co-funded by the IEE Intelligent Energy
Europe programme of the European Union managed by EASME, the European Commission
executive agency for SMEs.
SET – Production Processes and Efficiency Measures
1 – Executive summary
This document is the report of the work performed by the SET project team coordinated
by CITEVE for the purpose of 1) defining and structure the targeted basic textile
production processes, 2) collecting energy efficiency measures for machineries,
technologies and equipment, and 3) identify newly developed processes with potential to
replace traditional ones with gains in energy consumption.
Three levels of textile processes classification were defined. The first level corresponds to
the three value creation steps defined early in the project – Spinning (later replaced by
Yarn Production), Fabric Production and Finishing. The second level (phase) provides
more specific processes or steps inside the three main groups and in the third level (sub-
phase) are listed the most significant machineries, equipments or very specific processes,
in terms of energy use.
A list of 117 cross-cutting measures and 105 specific energy efficiency measures were
created, mostly based on Hasenbeigi [1](specific measures) and ARTISAN project (cross
cutting measures). This is far above the targeted 60 specific and 60 cross cutting. Each of
the identified specific measure was linked to a process or machinery listed on the second
or third level of process classification, respectively.
Newly developed processes can be found as measures for energy savings in Energy
Efficiency Measures chapter (e.g. Microwave Dyeing).
For the collection of these measures, teams were defined as in the following table:
Table 1 – Composition of the SET project teams collecting energy efficiency measures
Team Type of measures Process Organizations
1 Specific Yarn production DITF (DE) / IVGT (DE) / Centexbel (BE)
2 Specific Fabric production TMTE (HU)/ IVGT (DE)
3 Specific Finishing CITEVE (PT) / IVGT (DE)/ Inotex – ATOK (CZ)
4 Cross cutting ENEA (IT)
SET – Production Processes and Efficiency Measures
2 - Introduction
The need of reduce / rationalize energy consumption has assumed huge importance
during the last years with the growth of energy prices, environmental constraints and, in
some countries, legal obligations.
The rational use of energy calls for a broad application of energy efficiency technologies in
the various industrial sectors where energy is wasted. One of these energy intensive
industrial sectors to be considered to improve efficiency through the introduction of
energy conservation technologies and techniques is the textile industry.
Over the past decade there has been a decrease in the energy consumption of this industry
in the European Union (figure 1), which is mainly due to the economic situation but also
some improvements in energy efficiency. However, there is still room for further
improvements since the situation varies significantly within the EU members.
Figure 1– Energy consumption on Textile and Leather industries in EU (Source: Eurostat 29/10/2014)
The representation of energy costs, compared to the total costs of the company, in the case
of a vertical textile company, based in a study in Portugal, is estimated to be between 15%
to 25% [2]. Developing an understanding of how energy is used in a textiles plant is an
important component of improving the energy management. Knowing what the major
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SET – Production Processes and Efficiency Measures
end-users of energy in a plant are helps to identify what priorities need to be for energy
efficiency improvements.
Energy-efficiency improvement opportunities in the textile industry include opportunities
for process specific improvements, which includes retrofit/process optimization as well as
the complete replacement of the current machinery with state-of-the-art new technology,
and opportunities for cross cutting improvements in steam and/or thermal fluid boilers,
compressed air, conditioning, lighting, electrical motors and pumps, etc.
SET – Production Processes and Efficiency Measures
3 - Textile production processes
The textile industry is one of the most complex industrial chains in the manufacturing
industry because of the wide variety of textile products, substrates, processes, machinery
and components used, and finishing steps undertaken. Different types of fibers, methods
of yarn and fabric production, and finishing processes combinations (preparation,
printing, dyeing, chemical/mechanical finishing, etc), all interrelate in producing a finished
fabric. The combination of processes and process parameters is almost infinite and has a
considerable influence on energy efficiency.
Before collecting energy efficiency measures it was fundamental to develop a description
of the processes to be used on this project, from the huge variety available, to represent
the textile industry, taking mainly into account the energy consumption.
First, the major textile processes were defined for a first level of classification:
• Yarn production1
• Fabric Production
• Finishing
Within these main processes, two more specific levels of classification of processes used
on the textile industry were defined - second level of classification or phase and third level
of classification or subphase. This classification was based on ITMA 2015 Index of
Products [3], which is recognized and accepted by the textile sector.
The following tables represent the classification of textiles processes in the three different
levels to be considered in the next steps of this project and the associated hierarchical
identification.
Table 2 - Description of processes and equipments for Yarn Production
1 The expression “Yarn production” has replaced the original term “Spinning” in the first level of
classification in order to avoid repetition of terms in different levels, since “Spinning” was also being used in the second level of classification.
SET – Production Processes and Efficiency Measures
Process (Level 1)
Phase (Level 2)
Subphase (Level 3)
Yarn production (1)
Spinning Preparation for
cotton fibers (1.1)
Opening for cotton (1.1.1)
Cards (1.1.2)
Drawing machines for cotton (1.1.3)
Lap winders (1.1.4)
Combing machines for cotton (1.1.5)
Roving frames (1.1.6)
Spinning Preparation for wool
fibers (1.2)
Opening lines for raw wool (1.2.1)
Raw wool scouring lines (1.2.2)
Carbonising lines (1.2.3)
Opening for wool (1.2.4)
Worsted cards (1.2.5)
Semi-worsted cards (1.2.6)
Woollen cards (1.2.7)
Drawing machines for wool (1.2.8)
Combing machines for wool (1.2.9)
Back washing machines (1.2.10)
Finishers (1.2.11)
Roving frames for worsted yarn (1.2.12)
Production of man-made
filaments and fibres (1.3)
Extruders (1.3.1)
Winding (1.3.2)
Spinning (1.4)
Ring-spinning (1.4.1)
Compact spinning (1.4.2)
Rotor spinning (1.4.3)
Air-jet spinning (1.4.4)
Other Spinning machines (1.4.5)
Winding, reeling and covering
(1.5)
Winding machines (1.5.1)
Reeling machines (1.5.2)
Covering machines (1.5.3)
Yarn steaming, setting,
moistening and coating (1.6)
Autoclaves for steaming (1.6.1)
Heat-setting machines (1.6.2)
Moistening machines (1.6.3)
Yarn coating machines (1.6.4)
Texturing, bulking and
crimping (1.7)
Texturing machines (1.7.1)
Bulking and crimping machines (1.7.2)
Doubling and twisting (1.8) Doubling machines (1.8.1)
Twisting machines (1.8.2)
SET – Production Processes and Efficiency Measures
Table 3 - Description of processes and equipments for Fabric Production
Process (Level 1)
Phase (Level 2)
Subphase (Level 3)
Fabric production (2)
Weaving preparation (2.1)
Sectional warping (2.1.1)
Beam warping (2.1.2)
Draw-warping (2.1.3)
Beaming machines (2.1.4)
Sizing/slashing (2.1.5)
Indigo warp dyeing lines (2.1.6)
Weaving (2.2)
Rapier weaving (2.2.1)
Projectile weaving (2.2.2)
Air jet weaving (2.2.3)
Water jet weaving (2.2.4)
Shuttle looms (2.2.5)
Circular weaving (2.2.6)
Narrow fabrics weaving (2.2.7)
Preparation for knitting (2.3) Beam warping (2.3.1)
Sectional warping (2.3.2)
Knitting (2.4)
Circular knitting machines (2.4.1)
Flat knitting machines (2.4.2)
Warp knitting machines (2.4.3)
Knitting machines for special purposes (2.4.4)
SET – Production Processes and Efficiency Measures
Table 4 - Description of processes and equipments for Finishing
Process (Level 1)
Phase (Level 2)
Subphase (Level 3)
Finishing (3)
Pretreatment (3.1)
Carbonising (3.1.1)
Singeing (3.1.2)
Crabbing (3.1.3)
Desizing (3.1.4)
Bleaching batch (3.1.5)
Continuous Bleaching (3.1.6)
Yarn washing (3.1.7)
Rope washing (3.1.8)
Open-width washing (3.1.9)
Solvent washing (3.1.10)
Milling/fulling (3.1.11)
Yarn Mercerising (3.1.12)
Fabric Mercerising (3.1.13)
Dyeing (3.2)
Yarn continuous dyeing (3.2.1)
Fabric continuous dyeing (3.2.2)
Autoclaves (3.2.3)
Hank (3.2.4)
Jet (3.2.5)
Overflow (3.2.6)
Winch becks (3.2.7)
Jiggers (3.2.8)
Other dyeing machines (3.2.9)
Water extraction and drying (3.3)
Centrifugal hydro-extractors (3.3.1)
Stenter (3.3.2)
Yarn Dryers (3.3.3)
Fabric Dryers (3.3.4)
Other Dryers (3.3.5)
Tumblers (3.3.6)
Finishing machines (3.4)
Mechanical finishing (3.4.1)
Decatising (3.4.2)
Calenders (3.4.3)
Singeing machines (3.4.4)
Knitwear ironing presses (3.4.5)
Tumblers (3.4.6)
Sanfor (3.4.7)
Other finishing machines (3.4.8)
Printing (3.5)
Top and yarn printing (3.5.1)
Flat screen printing (3.5.2)
Rotary screen printing (3.5.3)
Inkjet Printing (3.5.4)
Other printing machines (3.5.5)
SET – Production Processes and Efficiency Measures
4 - Energy in the textile industry
In general, energy in the textile industry is mostly used in the forms of: electricity, as a
common power source for machinery, cooling and temperature control systems, lighting,
office equipment, conditioning, etc., and fuels for steam and thermal fluid boilers and
direct fired equipments.
In the next figure is represented a breakdown of energy consumption by type of energy for
the European Union (28 countries) for textile and leather industries in 2012.
Figure 2 - Breakdown of energy consumption by type of energy for the textile and leather industries in the
European Union on 2012 (source: Eurostat 29/10/2014)
Finishing processes have higher energy consumption than the yarn and fabric production.
Most of the energy used on those processes is thermal. Yarn and Fabric production mostly
use electricity as power source of the machines motors.
The following points present a slightly more detailed description of energy consumption
in each of the first level textile production processes: Yarn Production, Fabric Production
Solid Fuels1%
Petroleum8%
Natural Gas46%
Heat5%
Renewables0%
Electricity40%
Waste0%
Share of energy consumption by type in Textile and
Leather industries (EU28)
SET – Production Processes and Efficiency Measures
and Finishing, main variables affecting that consumption and reference values (when
available) for the consumption of each subphase.
4.1 - Energy use in yarn production, main factors affecting
energy consumption and reference values
Electricity is the major type of energy used in spinning plants. As an example, if the
spinning plant just produces raw yarn in a cotton spinning system, and does not dye or
fix the produced yarn, the fuel may just be used to provide steam for the humidification
system in the cold seasons for preheating the fibers before spinning them together [1].
The factors (triggers) which are most affecting the energy consumption for a
determined textile process in yarn production are presented in the following table, as
well as reference values of energy consumption (when available) for the processes
defined in the previous chapter.
Table 5 – Triggers and relevant product groups and benchmarks for Yarn Production
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Spinning
Preparation for
cotton fibers (1.1)
Opening for cotton
(1.1.1) Speed of machine
Opening of natural fibers and manmade fiber bales
Cards (1.1.2) Speed of machine
Drawing machines for
cotton (1.1.3) Speed of machine
Lap winders (1.1.4) Speed of machine
Combing machines for
cotton (1.1.5) Speed of machine high eveness and tension
Roving frames (1.1.6) Speed of machine, yarn count
Spinning
Preparation for
wool fibers (1.2)
Opening lines for raw
wool (1.2.1) Speed of machine
Raw wool scouring lines
(1.2.2) Speed of machine
Carbonising lines (1.2.3) Speed of machine, temperature
Opening for wool (1.2.4) Speed of machine
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations Worsted cards (1.2.5) Speed of machine
Semi-worsted cards
(1.2.6) Speed of machine
Woollen cards (1.2.7) Speed of machine
Spinning
Preparation for
wool fibers (1.2)
Drawing machines for
wool (1.2.8) Speed of machine
Combing machines for
wool (1.2.9) Speed of machine
Back washing machines
(1.2.10) Speed of machine, temperature
Finishers (1.2.11) Speed of machine, temperature
Roving frames for
worsted yarn (1.2.12) Speed of machine
Production of
man-made
filaments and
fibres (1.3)
Extruders (1.3.1) Speed of machine, temperature, number of nozzles
Winding (1.3.2) Speed of machine
Spinning (1.4)
Ring-spinning (1.4.1) Yarn count, twist factor, Speed of machine
High yarn tension and elongation
Compact spinning
(1.4.2) Yarn count, twist factor, Speed of machine
Smooth yarn surface, fine count
Rotor spinning (1.4.3) Yarn count, twist factor, Speed of machine
Smooth yarn surface,
Air-jet spinning (1.4.4) Yarn count, twist factor, Speed of machine
Special soft yarn with high hairiness, low tension
Other Spinning
machines (1.4.5) Variable, depending on the type of machine
Winding, reeling
and covering (1.5)
Winding machines
(1.5.1) Yarn count, Speed of machine
Reeling machines (1.5.2) Yarn count, Speed of machine
Covering machines
(1.5.3) Yarn count, Speed of machine
Yarn steaming,
setting,
Autoclaves for steaming
(1.6.1) Speed of machine, type of fibre, temperature
Cotton
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations moistening and
coating (1.6)
Heat-setting machines
(1.6.2) Speed of machine, type of fibre, temperature
Polyester
Moistening machines
(1.6.3) Speed of machine, type of fibre, temperature
Yarn coating machines
(1.6.4) Speed of machine, type of fibre, temperature
Yarns for circular knitting
Texturing,
bulking and
crimping (1.7)
Texturing machines
(1.7.1) Speed of machine, type of fibre, temperature
Bulking and crimping
machines (1.7.2) Speed of machine, type of fibre
Doubling and
twisting (1.8)
Doubling machines
(1.8.1) Yarn count, Speed of machine
Increase of yarn tension, multi-material mix
Twisting machines
(1.8.2) Yarn count, twist factor, Speed of machine
4.2 - Energy use in fabric production, main factors affecting
energy consumption and reference values
The weaving sector consumes almost only electricity. This sector is a major consumer
of compressed air, particularly when the looms are air jet. The amount of energy
consumed by each loom during its weaving operation can be estimated from the motor
capacity and weaving speed. Across the different weaving technologies, weft insertion
systems consume a large share of the total electricity use of the equipment. Usually,
the lighting has a great weight in terms of electricity consumption, because the
weaving sections have many lighting fixtures installed [5]. On the other hand, some
amount of thermal energy is consumed in sizing, as one of the possible preparatory
operations for weaving.
The energy consumption is not necessarily high for the knitting process. However, of
the main production facilities for this process, knitting machines have also been
undergoing a shift towards high speed and large capacity and fine gauge features; the
SET – Production Processes and Efficiency Measures
current industry trend is for high added-value goods and multi-line, small-volume
production based on advanced systems such as computer-controlled pattern making
mechanisms. Therefore, a potential tendency for increased energy consumption
should be taken into account [6].
The factors (triggers) which are most affecting the energy consumption for a
determined textile process in fabric production are presented in the following table, as
well as reference values of energy consumption (when available) for the processes
defined in the previous chapter.
Table 6 – Triggers and relevant product groups and benchmarks for Fabric Production
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Weaving preparation (2.1)
Sectional warping (2.1.1)
Repeatable patterns in warp direction, multicolor yarns
Clothing, home textiles, technical textiles with patterns
Beam warping (2.1.2) High-speed production for uncolored warps
Draw-warping (2.1.3) PES/PA filament yarns only
Technical textile warp
Beaming machines (2.1.4)
Sizing/slashing (2.1.5) Staple fiber yarns Yarns with a high hairiness, or electrostatic clamping
Indigo warp dyeing lines (2.1.6)
Denim/jeans production only
Weaving (2.2)
Rapier weaving (2.2.1)
Speed in bpm, width,
warp/weft density ,
shading motion or
Jacquard
Different yarn counts and appearance (flame yarn)
Projectile weaving (2.2.2)
Speed in bpm , width ,
warp/weft density ,
shading motion or
Jacquard
Even yarn count and same material
Air jet weaving (2.2.3)
Speed in bpm , width ,
warp/weft density ,
shading motion or
Jacquard
High production and even yarn caracteristic
Water jet weaving (2.2.4)
Yarn material which don’t take-up liquid
Filament yarns, tapes
Shuttle looms (2.2.5) Tubular fabrics Small quantities or specialized yarns
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Circular weaving (2.2.6) Tubular fabrics Filtersacks
Narrow fabrics weaving (2.2.7)
Tape and fabrics <30cm
Preparation for knitting (2.3)
Beam warping (2.3.1) For warp knitting only
Sectional warping (2.3.2)
Repateable patterns
Knitting (2.4)
Circular knitting machines (2.4.1)
Flat knitting machines (2.4.2)
Clothing
Warp knitting machines (2.4.3)
High production, thick yarn diameter, spacer fabrics
Home textiles, technical textiles
Knitting (2.4) Knitting machines for special purposes (2.4.4)
4.3 - Energy use in finishing, main factors affecting energy
consumption and reference values
Finishing is the major energy consumer in the textile industry because it uses a high
amount of thermal energy in the forms of both steam, thermal fluid, heat and gas for
direct fired equipments. The energy used in this process depends on various factors
such as the form of the product being processed (fiber, yarn, fabric), the machine type,
the specific process type, the combinations of processes, the state of the final product,
etc.
A significant share of thermal energy in a dyeing plant is lost through wastewater
discharge, heat released from equipment, exhaust gas loss, idling, evaporation from
liquid surfaces, un-recovered condensate, loss during condensate recovery, and during
product drying (e.g. by over-drying).
The factors (triggers) which are most affecting the energy consumption for a
determined textile process in fabric production are presented in the following table, as
well as reference values of energy consumption (when available) for the processes
defined in the previous chapter.
Table 7 – Triggers and relevant product groups and benchmarks for Finishing
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Pretreatment (3.1)
Carbonising (3.1.1) Speed of machine, temperature field
Singeing (3.1.2) Speed of gassing, machine type, type of fiber
Crabbing (3.1.3)
Velocity of machine, specific weight of fabric g/m2, temperature and pressure of the rollers
Pretreatment (3.1)
Desizing (3.1.4)
Liquor Ratio (L.R.) in discontinuous processes, type of fiber, machine type
[1] Desize unit - Desizing - Energy requirement (GJ/tonne output): 1,0 – 3,5
Bleaching batch (3.1.5)
Liquor Ratio (L.R.), type of fiber, machine type
[1] Kier - Scouring/Bleaching - Energy requirement (GJ/tonne output): 6,0 – 7,5 Jig/ winch - Bleaching - Energy requirement (GJ/tonne output): 3,0 – 6,5
Continuous Bleaching (3.1.6)
Type of fiber, machine type
[1] Open width range - Scouring/bleaching - Energy requirement (GJ/tonne output): 3,0 – 7,0
Yarn washing (3.1.7) Process temperature, type of fiber, machine type
Rope washing (3.1.8) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Open-width washing (3.1.9)
Process temperature, type of fiber, machine type
[1] 5 hot standing tanks before bleaching – 7,5 GJ/tonne 4 tanks, fully counter flow, with heat exchanger before bleaching- 2,8 GJ/tonne 5 tanks, fully counter flow, with heat exchanger before scouring/bleaching- 3,0 GJ/tonne 4 tanks counter flow and 1 cold standing tank before dyeing – 6,6 GJ/tonne 4 hot counter flow and 3 cold individual flow before printing – 10,5 GJ/tonne 4 hot counter flow with heat exchanger and 3 cold individual flow before printing – 5,5 GJ/tonne
Solvent washing (3.1.10)
Type of machine, velocity of machine, solvent flow rate, drying temperature
Milling/fulling (3.1.11)
Type of fiber, machine type
Yarn Mercerising (3.1.12)
Process temperature, type of fiber, machine type
Pretreatment (3.1)
Fabric Mercerising (3.1.13)
Process temperature, type of fiber, machine type
Dyeing (3.2)
Yarn continuous dyeing (3.2.1)
Process temperature, type of fiber, machine type
Fabric continuous dyeing (3.2.2)
Process temperature, type of fiber, machine type
[1] Continuous/Thermosol - Dyeing - Energy requirement (GJ/tonne output): 7,0 – 20,0 Pad/Batch - Dyeing - Energy requirement (GJ/tonne output): 1,5 – 4,5 [4] Woven dyeing - average energy specific consumption 1235,4 kgoe/tonne
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Autoclaves (3.2.3) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
[4] Yarn dyeing - Average energy specific consumption 1070,2 kgoe/tonne
Hank (3.2.4) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
[1] Hank - Dyeing - Energy requirement (GJ/tonne output): 10,0 – 16,0
Jet (3.2.5) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
[1] Jet - Dyeing - Energy requirement (GJ/tonne output): 3,5 – 16,0 [4] Dyeing of knitted fabric- Average energy specific consumption 671,5 kgoe/tonne
Overflow (3.2.6) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
Winch becks (3.2.7) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
Jiggers (3.2.8) Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
[1] Jig - Dyeing - Energy requirement (GJ/tonne output): 1,5 – 7,0
Dyeing (3.2) Other dyeing machines (3.2.9)
Liquor Ratio (L.R.), Bath temperature, type of fiber, machine type
[1] Beam - Dyeing - Energy requirement (GJ/tonne output): 7,5 – 12,5
Water extraction and drying (3.3)
Centrifugal hydro-extractors (3.3.1)
Moisture of the fabric at the entrance, type of fiber
Stenter (3.3.2)
Specific weight of fabric g/m2, moisture of the fabric at the entrance, type of fiber, drying temperature fields, velocity of machine
[1] Stenter - Drying - Energy requirement (GJ/tonne output): 2,5 – 7,5 Stenter - Heat Setting - Energy requirement (GJ/tonne output): 4,0 – 9,0
Yarn Dryers (3.3.3)
Moisture of the yarn at the entrance, type of fiber, drying temperature
[1] Hank - Drying - Energy requirement (GJ/tonne output): 4,5 – 6,5
SET – Production Processes and Efficiency Measures
Phase (Level 2)
Subphase (Level 3)
Triggers
Relevant product groups and
benchmarks for relevant trigger-
combinations
Fabric Dryers (3.3.4)
Specific weight of fabric g/m2, moisture of the fabric at the entrance, type of fiber, drying temperature fields
Other Dryers (3.3.5)
Specific weight of fabric g/m2, moisture of the fabric at the entrance, type of fiber, drying temperature fields
[1] Steam cylinders - Drying - Energy requirement (GJ/tonne output): 2,5 – 4,5
Tumblers (3.3.6) Type of fiber, drying temperature fields, speed of machine
Finishing machines (3.4)
Mechanical finishing (3.4.1)
Machine type, speed of machine
Decatising (3.4.2) Speed of machine, type of fiber, steam pressure
Calenders (3.4.3) Temperature and pressure of the rollers, speed of machine
Singeing machines (3.4.4)
Speed gassing, machine type
Knitwear ironing presses (3.4.5)
Temperature and pressure of the rollers, speed of machine
Tumblers (3.4.6) Type of fiber, drying temperature fields
Sanfor (3.4.7)
Specific weight of fabric g/m2, type of fiber, drying temperature fields, machine type
Other finishing machines (3.4.8)
Variable, depending on the type of machine
Printing (3.5)
Top and yarn printing (3.5.1)
Velocity of machine
Flat screen printing (3.5.2)
Drying temperature fields, machine type
[4] Printing - Average energy specific consumption 411,1 kgoe/tonne
Rotary screen printing (3.5.3)
Drying temperature fields, machine type
[1] Rotary Screen - Printing - Energy requirement (GJ/tonne output): 2,5 – 8,5
Inkjet Printing (3.5.4)
Number of colors, drying temperature
Other printing machines (3.5.5)
Variable, depending on the type of machine
SET – Production Processes and Efficiency Measures
5 - Energy efficiency measures
In this section is presented the list with the state of the art in energy efficiency
measures applicable within the textile industry. The list is divided in four main groups,
three of them complying the specific energy efficiency measures for Yarn Production,
Fabric Production and Finishing and also a group of cross cutting measures.
Specific energy efficiency measures include mostly retrofit/process optimization
measures but also measures considering the complete replacement of the current
machinery with state-of-the-art new technology.
At the end, 105 process specific and 117 cross cutting measures were obtained, mostly
based on Hasenbeigi [1](specific measures) and ARTISAN project (cross cutting
measures). The collected process specific energy efficiency measures result from case
studies around the world published in technical papers, some new available technologies
and the experience and knowledge of SET partners with textile companies. Cross cutting
measures were mostly compiled from ARTISAN (http://www.artisan-project.eu/) and
SESEC (http://www.euratex.eu/sesec/) projects. Based in scientific evidences and with
widespread application (with exception of new technologies), the measures here
presented are a useful guide of good practices to be used by textile companies to increase
their energy efficiency. The applicability of the proposed measures is represented in tables
8 and 9.
Table 8 – Number of specific energy efficiency measures per textile process (process and phase)
Process / Phase (Level 1/ Level 2)
Nº of measures
Process optimization
Newly developed processes
Yarn production (1) - -
Spinning Preparation for cotton fibers (1.1) 2 1
Spinning Preparation for wool fibers (1.2) - -
Production of man-made filaments and fibres (1.3) - -
Spinning (1.4) 20 4
Winding, reeling and covering (1.5) 2 -
Yarn steaming, setting, moistening and coating (1.6) 2 -
Texturing, bulking and crimping (1.7) - -
Doubling and twisting (1.8) 1 -
Fabric production (2) 2 -
Weaving preparation (2.1) 3 -
Weaving (2.2) 7 1
SET – Production Processes and Efficiency Measures
Process / Phase (Level 1/ Level 2)
Nº of measures
Process optimization
Newly developed processes
Preparation for knitting (2.3) - -
Knitting (2.4) - -
Finishing (3) 3 -
Pretreatment (3.1) 11 2
Dyeing (3.2) 20 4
Water extraction and drying (3.3) 18 1
Finishing machines (3.4) 1 -
Printing (3.5) - -
Table 9 – Number of cross cutting energy efficiency measures per applicability
Measure applicability Nº of measures
Reduction of peak power 2
Heating/Air conditioning 10
Electric motor 8
Compressed air 17
Pumping systems 17
Fan systems 10
Lighting 10
Steam systems 24
Vacuum systems 3
Cross cutting - general 16
The list of energy efficiency measures are presented in the following tables, together
with a short description of the measure, the applicable process, reference values of
energy savings (fuel and electricity) and an approach of the required investment cost
and the resulting payback period.
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
23
5.1 - Energy efficiency measures for Yarn Production process
Table 10 – Energy efficiency measures Yarn Production process
Measure (Action) Measure description Applied for Fuel Savings Electricity savings Investment Payback period (years)
Efficient Spindle Oil Use energy efficient spindle oil
Ring-spinning (1.4.1 ) no 3-7% of ring frame energy use
Installation of electronic Roving end-break stop-motion detector instead of pneumatic system
Installation of electronic Roving end-break stop-motion detector
Roving frames (1.1.6) no 3,2 MWh/year/machine
138€/roving machine
< 1
High speed carding machine New machine can be applied for Card
Cards (1.1.2) no yes 77000€/carding machine
<2
Optimum oil level in spindle bolsters
Optimum oil level Ring-spinning (1.4.1 ) no yes
Optimum oil level in spindle bolsters
Optimum oil level Compact spinning (1.4.2)
no yes
Replacement of lighter spindle in place of conventional spindle in Ring frame
Replacement spindle Ring-spinning (1.4.1 ) no 23 MWh/year/ring frame
10500€/ ring frame
8
Replacement of lighter spindle in place of conventional spindle in Ring frame
Replacement spindle Compact spinning (1.4.2)
no 23 MWh/year/ring frame
10500€/ ring frame
8
Synthetic sandwich tapes for Ring frames
Synthetic sandwich tapes for Ring frames
Ring-spinning (1.4.1 ) no 4.4-8 MWh/ ring frame/ year
415-525€/ ring frame
1-2
Synthetic sandwich tapes for Ring frames
Synthetic sandwich tapes for Ring frames
Compact spinning (1.4.2)
no 4,4-8 MWh/ ring frame/ year
415-525€/ ring frame
1-2
Optimization of ring diameter with respect to yarn count in ring frames
Optimization of ring diameter Ring-spinning (1.4.1 ) no 10% of ring frame energy use
1230€/ ring frame
2
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
24
Measure (Action) Measure description Applied for Fuel Savings Electricity savings Investment Payback period (years)
Optimization of ring diameter with respect to yarn count in ring frames
Optimization of ring diameter Compact spinning (1.4.2)
no 10% of ring frame energy use
1230€/ ring frame
2
False ceiling in Ring spinning section
False ceiling in Ring spinning section
Ring-spinning (1.4.1 ) no 8 KWh/ year/spindle 0.54€/spindle 1,2
False ceiling in Ring spinning section
False ceiling in Ring spinning section
Compact spinning (1.4.2)
no 8 KWh/ year/spindle 0,54€/spindle 1,2
Installation of energy efficient motor in ring frame
Installation of energy efficient motor
Ring-spinning (1.4.1 ) no 6,3-18,83 MWh/year/motor
1500-1700€/motor
2-4
Installation of energy efficient motor in ring frame
Installation of energy efficient motor
Compact spinning (1.4.2)
no 6,3-18,83 MWh/year/motor
1500-1700€/motor
2-4
Installation of energy-efficient excel fans in place of conventional aluminum fans in the suction of Ring Frame
Installation of energy-efficient excel fans
Ring-spinning (1.4.1 ) no 5,8-40 MWh/year/ ring frame
150-240€/ fan
<1
Installation of energy-efficient excel fans in place of conventional aluminum fans in the suction of Ring Frame
Installation of energy-efficient excel fans
Compact spinning (1.4.2)
no 5,8-40 MWh/year/ ring frame
150-240€/ fan
<1
The use of light weight bobbins in Ring frame
Use of light weight bobbins Ring-spinning (1.4.1 ) no 10,8 MWh/year/ring frame
500€/ ring frame
<1
The use of light weight bobbins in Ring frame
Use of light weight bobbins Compact spinning (1.4.2)
no 10,8 MWh/year/ring frame
500€/ ring frame
<1
High- speed ring spinning frame
High- speed ring spinning frame
Ring-spinning (1.4.1 ) no 10%-20% of ring frame energy use
Installation of soft starter on motor drive of Ring frame
Installation of soft starter on motor drive
Ring-spinning (1.4.1 ) no 1-5,2 MWh/year/ring frame
2
Installation of Variable Frequency Drive in Autocorner machine
Installation of Variable Frequency Drive
Winding machines (1.5.1 )
no 331,2 MWh/year/plant
15000€/plant <1
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
25
Measure (Action) Measure description Applied for Fuel Savings Electricity savings Investment Payback period (years)
Intermittent mode of movement of empty bobbin conveyor in the Autocorner/cone winding machines
Intermittent mode of movement
Winding machines (1.5.1 )
no 49,4 MWh/year/plant
850€/plant <1
Modified outer pot in Tow-For-One (TFO) machines
Modified outer pot in Tow-For-One (TFO) machines
Doubling machines (1.8.1 )
no 4% of TFO energy use
Optimization of balloon setting in Tow-For-One (TFO) machines
Optimization of balloon setting in Tow-For-One (TFO) machines
Doubling machines (1.8.1 )
no yes
Replacing the electrical heating system with steam heating system for the yarn polishing machine
Replacing the electrical heating system
Heat-setting machines (1.6.2)
increased 31.7 tonnes steam/year/machine
19,5 MWh/year/machine
750€/humidification plant
<1
Grinding of Tambour Sharpening of the surface Spinning Preparation for cotton fibers (1.1)
no yes 150€/card <1
Reduce room temperature Use machine heat for room heating by bypassing the suction exhaust
Rotor spinning (1.4.3) no yes
Monitoring and cleaning of rotor
Cleaning spin box Rotor spinning (1.4.3) no yes
<1
Cleaning of suction van Cleaning wastebox Rotor spinning (1.4.3) no yes
<1 Cleaning of spinnvalve Cleaning nozzle Air-jet spinning (1.4.4) no yes
<1
Use airfree compact Fitting of airfree compact on ringframe
Ring-spinning (1.4.1 ) no yes 11,5/spindle <1
Store yarn for 24 hours Relaxation of yarn Yarn steaming, setting, moistening and coating (1.6)
Don’t need steaming
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
26
5.2 - Energy efficiency measures for Fabric Production process
Table 11 – Energy efficiency measures Fabric Production process
Measure (Action) Measure description Applied for Fuel Savings Electricity savings Investment
Payback
period
(years)
Start periodic maintenance Maintenance with every article change
Fabric production (2)
Replace gripper Replace gripper Rapier weaving (2.2.1)
Replace gripper Replace projectile gripper Projectile weaving (2.2.2)
Reduce steam temperature Reduce steam temperature, use of pre-wetting and additional dry cylinder.
Sizing/slashing (2.1.5)
Use of cold size agent Use of cold size agent Sizing/slashing (2.1.5) no steam for size box necessary
Use of cold size agent use of cold size agent during beaming can cut out standard sizing for low hairy yarns
Sectional warping (2.1.1)
no need of separate sizing
6000/beaming machine
<2
Install automated pressure control valves
Pressure control valve Air jet weaving (2.2.3)
300/loom <2
Update nozzle software Software update to optimize the pressure distribution during weft insertion
Air jet weaving (2.2.3)
Use on-loom fabric inspection install a on-loom inspection system to minimize fabric inspection after weaving
Weaving (2.2)
1000/loom <2
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
27
Measure (Action) Measure description Applied for Fuel Savings Electricity savings Investment
Payback
period
(years)
Install mechanic selvage picker Replace air picker with mechanic picker
Air jet weaving (2.2.3)
reduce 1/3 of compressed air consumption per loom
800/loom <2
Replace single width loom Install double width loom for high volume articles
Weaving (2.2)
30000/loom <3
Install lower roof Reduce roof height to minimize the air volume of the room
Weaving (2.2)
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
28
5.3 - Energy efficiency measures for Finishing process
Table 12 – Energy efficiency measures Finishing process
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Combine Preparatory Treatments in wet processing
Combine preparatory treatments in order to lead to a reduction in process steps.
Pretreatment (3.1)
up to 80% of Preparatory Treatments energy use
Cold-Pad-Batch pretreatment
Embed hydrogen peroxide into the fabric using a padder, and the fabric is then stored to allow complete reaction between the fabric and chemicals prior to rinse.
Continuous Bleaching (3.1.6)
up to 38% of pretreatment fuel use
up to 50% of pretreatment electricity use
Bleach bath recovery system
Recycling and reuse of bleach bath.
Bleaching batch (3.1.5)
30000€ -93000€ saving (net annual operating savings (average per plant) which includes energy and non-energy savings)
Use of Counter-flow Current for washing
In this system, as the fabric runs through the washing compartments from entry to exit, clean water is passed through the plant from the back to the front. This means that the cleanest fabric comes into contact with the cleanest washing liquor.
Open-width washing (3.1.9)
41% - 62% of washing energy use
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
29
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Installing Covers on Nips and Tanks in continuous washing machine
The losses at nips are considerable. Hence, it is important to cover them as well as the hot tanks. Any fitted covers should be easily removable to allow quick access.
Open-width washing (3.1.9)
36%
Installing automatic valves in continuous washing machine
Automatic stop valves which link the main drive systems of machines to water flows can save considerable amounts of energy and water by shutting off water flow as soon as a stoppage occurs.
Open-width washing (3.1.9)
Yes < 0,5
Installing heat recovery equipment in continuous washing machine
Installing heat recovery equipment on a continuous washer is usually a simple but very effective measure since water inflow and effluent outflow are matched and this eliminates the need for holding tanks.
Open-width washing (3.1.9)
Yes
Reduce live steam pressure in continuous washing machine
A reduction in live steam pressure can prevent steam breakthroughs, thus improving heat transfer efficiency in direct steam heating applications. Similarly, reducing steam pressure in closed coils will have take advantage of the fact that lower pressure steam has higher latent heat content.
Open-width washing (3.1.9)
Yes
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
30
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Introducing Point-of-Use water heating in continuous washing machine
Point-of-use gas-fired water heaters can be used to enable processes to be run independently of plant central boiler systems. This means that boiler and distribution losses associated with centralized systems can be eliminated.
Open-width washing (3.1.9)
<50% High
Interlocking the running of exhaust hood fans with water tray movement in the yarn mercerizing machine
Electrically interlock the exhaust hood fans with the forward movement of the water tray, as the fans usually have to remove the fumes generated during the washing phase only.
Yarn Mercerising (3.1.12)
12,3 MWh/year/machine
<0,5
Energy saving in cooling blower motor by interlocking it with fabric gas singeing machine's main motor
Interlock the cooling blower motor with the singeing machine’s main motor, thereby saving energy.
Singeing (3.1.2) 2,43 MWh/year/machine
< 0,5
Energy saving in shearing machine's blower motor by interlocking it with the main motor
The interlocking of blower motors with the machine’s main motor can be implemented in fabric shearing machines.
Mechanical finishing (3.4.1)
2,43 MWh/year/machine
< 0,5
Enzymatic removal of residual hydrogen peroxide after bleach
Rinsing steps after peroxide bleaching can be reduced with enzymatic peroxide removal (normally only one rinsing step with hot water is necessary).
Bleaching batch (3.1.5)
2780 GJ/year/plant
Enzymatic scouring With the use of enzymes the alkaline scouring process can be replaced.
Bleaching batch (3.1.5)
Yes
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
31
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Installation of Variable Frequency Drive on pump motor of Top dyeing machines
Variable frequency drives (VFDs) can be installed on the pump motor of the top dyeing machine in order to save energy by setting the speed of the pump motor based on the dyeing process requirements.
Autoclaves (3.2.3)
26,9 MWh/year/machine
2400€ /machine 1,5
Heat Insulation of high temperature/ high pressure dyeing machines
Insulation of pipes, valves, tanks and machines is a general principle of good housekeeping practice that should be applied in all steam consuming processes in textile plants. The insulation material may be exposed to water, chemicals and physical shock. Any insulation should, therefore, be covered or coated with a hard-wearing, chemical/water resistant outer layer.
Autoclaves (3.2.3)
2% in steam consumption per kilogram of dyed yarn
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
32
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Heat Insulation of high temperature/ high pressure dyeing machines
Insulation of pipes, valves, tanks and machines is a general principle of good housekeeping practice that should be applied in all steam consuming processes in textile plants. The insulation material may be exposed to water, chemicals and physical shock. Any insulation should, therefore, be covered or coated with a hard-wearing, chemical/water resistant outer layer.
Jet (3.2.5) 4 GJ/tonne fabric/plant
6,3 kWh/tonne fabric
4€/tonne of fabric
Automated preparation and dispensing of chemicals in dyeing plants
Automatic preparation and dispension of chemicals generate a reduction of consumption of chemicals, energy and water and an increase of reproducibility.
Dyeing (3.2) Yes
Chemical Dispensing System: 117500€ -698000€ ; Dye Dissolving and Distribution: 78500€ - 313750€; Bulk Powder Dissolution and Distribution: 59500€ - 470500€
1,3 - 6,2 ; 4 - 5,7 ; 3,8 - 7,5
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
33
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Automatic dye machine controllers
Automatic dye machine controllers offer an effective means for enhanced control over dyeing processes, based on microprocessors, allowing for feedback control of process parameters such as pH, color, and temperature. They analyze process parameters continuously and respond more quickly and accurately than manually controlled systems.
Dyeing (3.2) Yes 44700€ - 117600€/system
1 - 5
Cooling water recovery in batch dyeing machines (Jet, Beam, Package, Hank, Jig and Winches)
Cooling water and condensate water can be pumped to hot water storage tanks for reuse in functions where heated water is required.
Dyeing (3.2) 1,6 - 2,1 GJ/tonne fabric
112000€ - 166000€/system
1,3 - 3,6
Cold-Pad-Batch dyeing system
Impregnate the fabric with liquor containing premixed fiber-reactive dyestuff and alkali. Excess liquid is squeezed out on a device known as a mangle. The fabric is then batched onto rolls or into boxes and covered with plastic film to prevent absorption of CO2 from the air and evaporation of water. The fabric is then stored for 2 – 12 hours.
Fabric continuous dyeing (3.2.2)
16,3 GJ/tonne of dyed fabric
953000€/ system 1,4 - 3,7
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
34
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Discontinuous dyeing with airflow dyeing machine
Airflow dyeing machines have lower liquor ratios than conventional jet dyeing machines. To achieve those low liquor ratios, within the jet dyeing machine the fabric is moved by moisturized air or a mixture of steam and air only (no liquids), aided by a winch. The prepared solutions of the dyestuffs, auxiliaries and basic chemicals are injected into the gas stream.
Jet (3.2.5) up to 60% of machine's fuel use
149500€ - 284000€/machine
Installation of VFD on circulation pumps
Circulation pumps are used to circulate chemicals in machine chambers in the dye house. VFDs can be installed instead of ball valves for flow control, thereby saving energy.
Dyeing (3.2) 138 MWh/year/plant
1800€/plant < 1
Dyebath Reuse
Dyebath reuse is the process by which exhausted hot dyebaths are analyzed for residual colorant concentrations, replenished, and reused to dye additional batches of material.
Dyeing (3.2) 3500€ saving/ dye machine
18800€ - 26600/dye machine
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
35
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Single-rope flow dyeing machines
The way in which these machines handle the fabric and the dyeing cycle is very different from conventional rope dyeing machines. First, there is only one fabric rope which passes through all flow groups and compartments, returning to the first compartment after the lap is complete.
Other dyeing machines (3.2.9)
2,5 kg steam /kg fabric
0,16 - 0,20 kWh/kg fabric
< 1
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
36
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Microwave dyeing equipment
Microwave dyeing equipment employs microwaves for rapid, efficient and energy-saving dispersion and penetration of dyes and chemicals into fabric. Since microwave irradiation generates heat through dielectric losses, the heat is absorbed by objects having large losses, and thus fabric containing moisture is heated without heating of the surrounding air and equipment itself. Furthermore, in contrast to the case of moisture (dyeing solution) penetrating the fabric, the fabric itself becomes a steam generator through internal heating, and penetration and dispersion of dyes and chemicals occurs rapidly and uniformly, ensuring suitability for continuous dyeing in mass production.
Other dyeing machines (3.2.9)
96% reduction compared to beam dyeing
90% reduction compared to beam dyeing
353000€/ machine
Reducing the process temperature in wet batch pressure-dyeing machines
A reduction in the process temperature may also be achieved in wet batch pressure-dyeing machines by introducing alternative processes.
Dyeing (3.2) Yes
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
37
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Use of steam coil instead of direct steam heating in batch dyeing machines (Winch and Jigger)
In older batch dyeing machines like winches and jiggers, dyebaths are traditionally heated by sparging with raw steam. This is a very inefficient use of steam for heating the dyebath. A steam coil submerged in the dyebath now allows for the recycling of the condensate, resulting in significant fuel savings.
Dyeing (3.2) 4580 GJ/year/plant 130000€/plant
Reducing the process time in wet batch pressure-dyeing machines
Processing times can sometimes be reduced simply by making modifications to the temperature profiles of certain dyeing cycles.
Dyeing (3.2) Yes
Installation of covers or hoods in atmospheric wet batch machines
Using covers or hoods can reduce evaporative losses by approximately half.
Dyeing (3.2) Yes
Careful control of temperature in atmospheric wet batch machines
Better temperature control in order to decrease steam comsuption when the process temperature is reached.
Jiggers (3.2.8) 27 - 91 kg steam/hour
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
38
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Jiggers with a variable liquor ratio
A new generation of jiggers with a variable liquor ratio has been developed in order to be able of processing. These jiggers make use of a heat exchanger, allowing the heat to be removed and applied elsewhere in the plant. In each passage, the length of the cloth is measured, so extra fabric at the end of the batch can be avoided.
Jiggers (3.2.8) 26% reduction compared to conventional jigger
Heat recovery of hot waste water in Autoclave
Installation of a heat exchanger and surrounding equipment like water tanks and pumps for recovering heat from hot waste water as a heat source.
Autoclaves (3.2.3)
554 MJ/batch product
Insulation of un-insulated surface of Autoclave
All the hot surfaces should be insulated, including those of the main vessel, air vent tank, heat exchanger and water circulation piping. Water-resistant, easy-paste type insulation material is usually recommended.
Autoclaves (3.2.3)
15 MJ/batch product
Reducing the need for re-processing in dyeing
Improving process control either mannually through better staff training or using specific software.
Dyeing (3.2) 10% -12%
Recover heat from hot rinse water
Capture the heat from the rinse water and use it for pre-heating the incoming water for the next hot rinse.
Dyeing (3.2) 1,4 - 7,5 GJ/tonne fabric rinsed
34500€ -74500€ < 0,5
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
39
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Reuse of washing and rinsing water
After discontinuous dyeing, the final-step rinse water is hardly contaminated and can possibly be reused for the first rinsing step of the next dyeing process.
Dyeing (3.2) Yes
Reduce rinse water temperature
Reduce temperature of rinse water for rinsing after dyeing to about 50°C can be done without degrading product quality.
Dyeing (3.2) 10% 0
Introduce Mechanical Pre-drying
Mechanical pre-drying methods such as mangling, centrifugal drying, suction slot or air knife de-watering are used to reduce drying costs by removing some of the water from the fabric prior to contact drying in cylinder dryer.
Water extraction and drying (3.3)
Yes
Recover Condensate and Flash Steam
Since a large amount of steam is used in cylinder dryer, there is also a significant amount of condensate that should be recovered and returned to the boiler house. In addition, flash steam which is produced when condensate is reduced to atmospheric pressure can be recovered as low-pressure steam, and used to heat water or other low-pressure steam processes.
Other Dryers (3.3.5)
Yes
End Panel Insulation Insulation of end sections of the cylinder dryers.
Other Dryers (3.3.5)
Yes
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
40
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Avoid Intermediate Drying
There are systems which allow finishes to be applied ‘wet on wet’ to avoid intermediate drying between processes.
Water extraction and drying (3.3)
Yes
Avoid Overdrying
Control the speed of the drying cylinders so that the equilibrium moisture level of the fibre is not exceeded.
Other Dryers (3.3.5)
Yes
Reduce Idling Times and Use Multiple Fabric Drying
Careful scheduling of fabric batches arriving at the cylinders to reduce idling time, and make cylinders extra wide to allow two batches of narrow fabric to run side by side.
Other Dryers (3.3.5)
Yes
Maintenance of the cylinder dryer
Avoid steam leaks performing adequate maintenance.
Other Dryers (3.3.5)
The use of radio frequency dryer for drying acrylic yarn
The steam heated dryer, which is used to dry dyed acrylic yarn skeins, can be replaced by a radio frequency dryer.
Yarn Dryers (3.3.3)
35300€ saving/plant 157000€/plant
The use of Low Pressure Microwave drying machine for bobbin drying instead of dry-steam heater
Switching the drying of bobin products from dry-steam heaters to low pressure (LP) microwave drying.
Yarn Dryers (3.3.3)
Yes 107 kWh/tonne yarn
392000€/plant < 3
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
41
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Conversion of Thermic Fluid heating system to Direct Gas Firing system in Stenters and dryers
Replace thermal fluid heaters by direct gas firing systems. In the new system, air is directly heated by gas fired burners and the required temperature is obtained by circulating hot air through the chambers. This measure provides savings on fuel consumption with the reduced heat losses and on the electricity required for pumping the thermic fluid.
Stenter (3.3.2) 11000 GJ/year/plant 120 MWh/year/plant
39200€/plant 1
Introduce Mechanical De-watering or Contact Drying Before Stenter
Use mechanical water extraction equipment such as mangles, centrifuges, suction slots and air knives; or contact drying using heated cylinders.
Stenter (3.3.2) 13% - 50% of stenter energy use
Avoid Overdrying Control the speed of the stenter so that the equilibrium moisture level of the fibre is not exceeded.
Stenter (3.3.2) Yes
Close Exhaust Streams during Idling
Perform proper scheduling to minimize machine stops and close exhausts during idling times.
Stenter (3.3.2) Yes
Proper Insulation Proper insulation of stenter envelopes reduces heat losses to a considerable extent.
Stenter (3.3.2) 20% of stenter energy use
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
42
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
Optimize Exhaust Humidity
In order to optimize drying rates and energy use, air flows through the oven (and therefore the exhaust rate) must be carefully controlled, analysing the moisture content of the exhaust air.
Stenter (3.3.2) 20 - 80% of stenter energy use
Install Heat Recovery Equipment
Heat-recovery air/air: Uses exhaust air heat to heat up fresh air supplied to the stenter
Stenter (3.3.2) Yes
Install Heat Recovery Equipment
Heat-recovery air/water: Uses exhaust air heat to heat up service water for wet finishing (for example washing, dyeing, and bleaching.)
Stenter (3.3.2) 30% of stenter energy use
60400€ - 361000€/system
1,5-6,6
Efficient burner technology in Direct Gas Fired systems
Optimized firing systems and sufficient maintenance of burners in direct gas-fired stenters can minimize methane emissions, which is important because methane emissions from burners greatly determine actual burner capacity. Stenters should receive general maintenance by specialized companies at regular intervals. There should also be routine checking of the burner air inlet for blockings by lint or oil, cleaning of pipe works to remove precipitates and adjusting of burners by specialists.
Stenter (3.3.2) Yes
SET – Production Processes and Efficiency Measures
NOTE: The energy efficiency measures highlighted in bold are referent to newly developed processes.
43
Measure (Action) Measure description Applied for Fuel Saving Electricity
Savings Investment
Cost
Payback period (years)
The Use of Sensors and Control Systems in Stenter
Install sensors and control systems such as: Exhaust humidity measurement; Residual moisture measurement; Fabric and air temperature measurement; Process visualization systems
Stenter (3.3.2) 22% of stenter fuel use
11% of stenter electricity use
moisture humidity controllers: 15700€ – 172500€; dwell time controls: 63000€ – 314000€
moisture humidity controllers: 1,5 - 5 ; dwell time controls: 4 - 6,7
Automatic steam control valves in Desizing, Dyeing, and Finishing
Replace the manual steam control system with an automatic one, which controls the steam supply to each process according to its needs.
Finishing (3) 3250 GJ/year/plant 4000€/plant
The recovery of condensate in wet processing plants
Recover the condensate to return it to the boiler and convert it back into new steam or use it as a water supply for washing or desizing, thereby recovering both water and heat.
Finishing (3) 1,3 - 2 GJ/tonne fabric
800€ - 12500€ 1 - 6
Utilization of heat exchanger for heat recovery from wet-processes wastewater
Recover the energy of heated waste water from rinsing in the desizing, scouring, and bleaching steps of continuous preparation ranges as well as in dyeing machines.
Finishing (3) 1,1 – 1,4 GJ/tonne finished fabric
258000€ / system
SET – Production Processes and Efficiency Measures
44
5.4 - Cross-cutting energy efficiency measures
Table 13 – Cross cutting energy efficiency measures
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Reconsideration of electric supply contract.
It is an economic measure 0% (no energy saving, but there may be economic saving)
Negligible Immediate
Reconsideration of thermal supply contract / cost of used combustibles.
It is an economic measure
0% (no energy saving, but there may be economic saving)
Negligible Immediate
Shifting of energivorous processes towards lower price time slots.
Reduction of peak power
0% (no energy saving, but there may be economic saving)
Slight Immediate
Use of work-shifts. Reduction of peak power
Low/Medium Immediate
Removal of covering / impediments from heating appliances and air conditioners.
Heating/Air conditioning
from 0 to 1% of factory thermal consumption
from 0 to 1% of factory electrical consumption
Slight Short - Short/Medium - Medium
Adoption of high efficiency window frames.
Heating/Air conditioning
from 0 to 20% of thermal consumption in shed building with window frames in polycarbonate and where the heat is only used for building heating
Low/Medium Medium
SET – Production Processes and Efficiency Measures
45
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Exterior Insulation and Finishing System (EIFS).
Heating/Air conditioning
from 0 up to 50% of thermal consumption in case of heat used only for building heating
Medium/High Medium - Medium/Long
Limitation of heated / conditioned volumes (it can be sufficient to spread a nylon sheet).
Heating/Air conditioning
up to 3% of factory thermal consumption
up to 2% of factory electric consumption
Low - Low/Medium Medium - Variable
Set thermostats to minimum for comfort (20ºC in winter and 25ºC in summer).
Heating/Air conditioning
Variable, A typical value is < = 1% of factory thermal consumption
Variable A typical value is 1,5% of factory electrical consumption
Null immediate
Guarantee closed passages between acclimatized and non acclimatized areas.
Minimise loss of hot/cold air. Use air curtains when passages from climatized and non climatized areas are usually and inevitably open.
Heating/Air conditioning
Variable < = 1% of factory thermal consumption
Variable < = 1% of factory electrical consumption
Slight immediate
Use heat/cooling only when area is occupied.
Applies for comfort areas, technical areas such as server rooms, display rooms, etc. should be analyzed seperatly.
Heating/Air conditioning
Variable < = 1% of factory thermal consumption
Variable < = 1% of factory electrical consumption
Null immediate
Clean and effective heaters/coolers. Verify dirt deposition in all heat transfer surfaces.
Heating/Air conditioning
Variable < = 1% of factory thermal consumption
Variable < = 1% of factory electrical consumption
Negligible immediate
SET – Production Processes and Efficiency Measures
46
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Adoption of sunbreakers / curtains.
Heating/Air conditioning
from 0 to 1% of factory electrical consumption (energy savings related to lower use of the air-conditioning)
Low Short/Medium
Adoption of high efficiency electric engine.
Electric motor
from 0 up to 10% of factory electrical consumption in case of obsolete engines
High Medium - Medium/Long
Adoption of inverters for electric motor.
Adjustable-speed drives better match speed to load requirements for motor operations, and therefore ensure that motor energy use is optimized to a given application.
Electric motor 2% - 60% Medium from 0,8 to 2,8 years
SET – Production Processes and Efficiency Measures
47
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Adoption of motor management plan.
A motor management plan is an essential part of a plant’s energy management strategy. Having a motor management plan in place can help companies realize long-term motor system energy savings and will ensure that motor failures are handled in a quick and cost effective manner. The Motor Decisions Matter Campaign suggests the following key elements for a sound motor management plan (CEE, 2007): 1. Creation of a motor survey and tracking program. 2. Development of guidelines for proactive repair/replace decisions. 3. Preparation for motor failure by creating a spares inventory. 4. Development of a purchasing specification. 5. Development of a repair specification. 6. Development and implementation of a predictive and preventive maintenance program.
Electric motor
SET – Production Processes and Efficiency Measures
48
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Maintenance of motors.
The purposes of motor maintenance are to prolong motor life and to foresee a motor failure.
Electric motor 2% - 30% of motor system energy use
Rewinding of motors.
In some cases, it may be cost-effective to rewind an existing energy-efficient motor, instead of purchasing a new motor.
Electric motor
Proper motor sizing. Electric motor
Power factor correction.
The power factor can be corrected by minimizing idling of electric motors (a motor that is turned off consumes no energy), replacing motors with premium-efficient motors, and installing capacitors in the AC circuit to reduce the magnitude of reactive power in the system (U.S. DOE, 1996).
Electric motor
SET – Production Processes and Efficiency Measures
49
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Minimizing voltage unbalances.
Electric motor
The typical payback period for voltage controller installation on lightly loaded motors in the U.S. is 2,6 years (U.S. DOE-IAC, 2006)
Reduction of demand throught reduction of compressed air production pressure.
Compressed air
from 0 to 1% of electrical consumption if the compressed air is used improperly for cleaning reasons from 0 to 0,1% in other cases
Null Immediate
Reduction of leaks in compressed air pipes and equipment.
Leaks cause an increase in compressor energy and maintenance costs. The most common areas for leaks are couplings, hoses, tubes, fittings, pressure regulators, open condensate traps and shut-off valves, pipe joints, disconnects and thread sealants.
Compressed air up to 20% of compressed air system energy use
Low Short - Short/Medium
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50
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Installation of compressed air accumulation tanks.
Compressed air about 0% Low - Low/Medium Short - Short/Medium
Recovery of heat from compressors.
Compressed air up to 20% of compressed air system energy use
Medium < 1
Install low-cost solenoid valves on air supply lines to individual machines. Switch off compressed air supply as soon as machine is switched off.
Compressed air Variable < = 1% of electrical consumption
Low Short
Use lowest air intake temperature possible in compressors. Duct air intake to ensure coolest possible and/or pre-cool it.
Reducing the inlet air temperature reduces energy used by the compressor. In many plants, it is possible to reduce this inlet air temperature by taking suction from outside the building.
Compressed air each 3°C reduction will save 1% compressor energy use
Low/Medium < 5
Check on correct pressure setting regularly to reduce the demand.
Compressed air < = 1% of electric consumption
Null immediate
Replace pneumatic tools by electrical tools to reduce the demand.
Compressed air < = 1% of electric consumption
Low/Medium Short
Do not use compressed air for cleaning operations. Use of vacuum cleaner instead of compressed air.
Compressed air Variable < = 1% of electrical consumption
Negligible immediate
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51
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Maintenance of compressed air plant.
Inadequate maintenance can lower compression efficiency, increase air leakage or pressure variability and lead to increased operating temperatures, poor moisture control and excessive contamination. Better maintenance will reduce these problems and save energy.
Compressed air
Monitoring of compressed air plant.
Maintenance can be supported by monitoring using proper instrumentation, including (CADDET, 1997): • Pressure gauges on each receiver or main branch line and differential gauges across dryers, filters, etc. • Temperature gauges across the compressor and its cooling system to detect fouling and blockages. • Flow meters to measure the quantity of air used. • Dew point temperature gauges to monitor the effectiveness of air dryers. • kWh meters and hours run meters on the compressor drive.
Compressed air
SET – Production Processes and Efficiency Measures
52
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Adoption of electronic condensate drain traps (ECDTs) for compressed air plant.
Due to the necessity to remove condensate from the system, continuous bleeding, achieved by forcing a receiver drain valve to open, often becomes the normal operating practice, but is extremely wasteful and costly in terms of air leakage. Electronic condensate drain traps (ECDTs) offer improved reliability and are very efficient as virtually no air is wasted when the condensate is rejected.
Compressed air
Maximizing allowable pressure dew point at air intake in compressed air system.
Choose the dryer that has the maximum allowable pressure dew point, and best efficiency. A rule of thumb is that desiccant dryers consume 7 to 14% and refrigerated dryers consume 1 to 2% of the total energy of the compressor (Ingersoll-Rand, 2001). Consider using a dryer with a floating dew point. Note that where pneumatic lines are exposed to freezing conditions, refrigerated dryers are not an option.
Compressed air
SET – Production Processes and Efficiency Measures
53
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Optimizing the compressor to match its load.
Some plants have installed modular systems with several smaller compressors to match compressed air needs in a modular way (Cergel et al., 2000). In some cases, the pressure required is so low that the need can be met by a blower instead of a compressor which allows considerable energy savings, since a blower requires only a small fraction of the power needed by a compressor (Cergel et al., 2000).
Compressed air
Proper pipe sizing for compressed air plant.
Compressed air up to 3% of compressed air system energy use
Adoption of inverters for electric motors of compressed air plant.
When there are strong variations in load and/or ambient temperatures there will be large swings in compressor load and efficiency.
Compressed air
Implementing adjustable speed drives in rotary compressor systems has saved 15% of the annual compressed air system energy consumption
Medium
Remove/isolate "dead-legs" and redundant Pipework of compressed air system.
Compressed air
Use of high efficiency pump for sewages.
Pumping systems
< = 1% of electrical consumption
Variable Variable
SET – Production Processes and Efficiency Measures
54
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Maintenance of pumping systems.
Inadequate maintenance lowers pump system efficiency, causes pumps to wear out more quickly and increases costs. Better maintenance will reduce these problems and save energy. Proper maintenance includes the following (Hydraulic Institute, 1994; U.S. DOE, 1999): • Replacement of worn impellers, especially in caustic or semi-solid applications. • Bearing inspection and repair. • Bearing lubrication replacement, once annually or semiannually. • Inspection and replacement of packing seals. • Inspection and replacement of mechanical seals. • Wear ring and impeller replacement. • Pump/motor alignment check. • The largest opportunity is usually to avoid throttling losses.
Pumping systems
2% - 7% of pumping electriccity use
< 1
SET – Production Processes and Efficiency Measures
55
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Monitoring of pumping systems.
Monitoring in conjunction with operations and maintenance can be used to detect problems and determine solutions to create a more efficient system. Monitoring can determine clearances that need be adjusted, indicate blockage, impeller damage, inadequate suction, operation outside preferences, clogged or gas-filled pumps or pipes, or worn out pumps. Monitoring should include: • Wear monitoring • Vibration analyses • Pressure and flow monitoring • Current or power monitoring • Differential head and temperature rise across the pump (also known as thermodynamic monitoring) • Distribution system inspection for scaling or contaminant build-up
Pumping systems
SET – Production Processes and Efficiency Measures
56
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Controls for pumping systems.
The objective of any control strategy is to shut off unneeded pumps or to reduce the load of individual pumps. Remote controls enable pumping systems to be started and stopped relatively quickly and accurately, and reduce the required labor with respect to traditional control systems.
Pumping systems
Reduction of demand for pumping systems.
Holding tanks can be used to equalize the flow over the production cycle, enhancing energy efficiency and potentially reducing the need to add pump capacity. In addition, bypass loops and other unnecessary flows should be eliminated. Energy savings may be as high as 5-10% for each of these steps (Easton Consultants, 1995).
Pumping systems
Adoption of more efficient pumps.
Pumping systems
2% - 10% of pumping electricity use
Proper pump sizing. Pumping systems
Correcting for pump oversizing can save 15% to 25% of electricity consumption for pumping (on average for the U.S. industry) (Easton Consultants, 1995).
< 1
SET – Production Processes and Efficiency Measures
57
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Multiple pumps for varying loads.
Pumping systems
The installation of parallel systems for highly variable loads on average would save 10% to 50% of the electricity consumption for pumping for the U.S. industry (Easton Consultants, 1995).
Impeller trimming (or shaving sheaves) for pumping systems.
Trimming reduces the impeller’s tip speed, which in turn reduces the amount of energy imparted to the pumped fluid; as a result, the pump’s flow rate and pressure both decrease. A smaller or trimmed impeller can thus be used efficiently in applications in which the current impeller is producing excessive heat (U.S. DOE-OIT, 2005).
Pumping systems
In the food processing, paper and petrochemical industries, trimming impellers or lowering gear ratios is estimated to save as much as 75% of the electricity consumption for specific pump applications (Xenergy, 1998).
Adjustable speed drives (ASDs) for pumping systems.
Pumping systems
20% - 50% of pumping electricicy use
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58
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Avoiding throttling valves for pumping systems.
Variable speed drives or on-off regulated systems always save energy compared to throttling valves (Hovstadius, 2002).The use of these valves should therefore be avoided. Extensive use of throttling valves or bypass loops may be an indication of an oversized pump (Tutterow et al., 2000).
Pumping systems
Proper pipe sizing for pumping plant.
Pumping systems
Replacement of belt drives in pumping systems.
Pumping systems
up to 8% of pumping electricity use
< 0,5
Precision castings, surface coatings or polishing in pumping systems.
The use of castings, coatings or polishing reduces surface roughness that in turn, increases energy-efficiency. It may also help maintain efficiency over time. This measure is more effective on smaller pumps.
Pumping systems
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59
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Improvement of sealing in pumping systems.
Seal failure accounts for up to 70% of pump failures in many applications (Hydraulic Institute and Europump, 2001). The sealing arrangements on pumps will contribute to the power absorbed. Often the use of gas barrier seals, balanced seals, and no-contacting labyrinth seals can help to optimize pump efficiency.
Pumping systems
Repair leaks in ventilation pipework.
Fan systems Variable < = 1% of electrical consumption
Low Short
Minimizing pressure in fun systems.
Fan systems
Control density in fun systems.
Temperature, moisture, molecular weight, elevation, and the absolute pressure in the duct or vessel affect the density of the transporting gas. A density change may affect the hardware requirements for the system.
Fan systems
Fan efficiency. Fan systems Proper fan sizing. Fan systems 1-5% Adjustable speed drives (ASDs) for fan systems.
Fan systems 14% - 49% of fan system electricity use
SET – Production Processes and Efficiency Measures
60
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
High efficiency belts (cogged belts) for fan systems.
Standard Vbelts tend to stretch, slip, bend and compress, which lead to a loss of efficiency. Replacing standard V-belts with cogged belts can save energy and money, even as a retrofit.
Fan systems 2% of fan system electricity use
1- 3 years
Adoption of proximity sensors for not permanently used places.
Lighting from 0 to 2% of factory electrical consumption
Slight < 2
Substitution of mercury-vapor lamps with fluorescent tubes in low buildings.
Lighting from 0 to 3% of factory electrical consumption
Low - Low/Medium - Medium
Short
Adoption of LED Lamps. Lighting from 0 to 5% of factory electrical consumption
Medium - Medium/High
Medium
Down lamps or lower the ceiling.
Lighting from 0 to 5% of factory electrical consumption
Variable Variable
Maintain lamps and fixtures clear of light-blocking dust and dirt.
Lighting
Variable A typical value is 1,1% of factory electrical consumption
Slight immediate
Make the best use of daylight.
In addition to optimizing the size of the windows, a transparent sheets can be installed at the roof in order to allow more sunlight to penetrate into the production area. This can reduce the need for lighting during the day.
Lighting Variable < = 1% of factory electrical consumption
Variable Short/Medium
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61
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Avoid the absorption of light by the surroundings (light-coloured wall, ceilings, and floors).
Lighting
Variable A typical value is 1,5% of factory electrical consumption
Low Short
Replace magnetic ballasts with electronic ballasts.
A ballast is a mechanism that regulates the amount of electricity required to start a lighting fixture and maintain a steady output of light.
Lighting
Electronic ballasts save 12 – 25% of electricity use compared to magnetic ballast.
Optimization of plant lighting (lux optimization) in production and non-production departments.
Lighting
Adoption of dimmer to reduce the use of artificial light.
Lighting
Reduction of steam production pressure.
Steam systems up to 2% of factory thermal consumption
Null Immediate
Installation of steam accumulation tanks.
Steam systems about 0% Low - Low/Medium Immediate
SET – Production Processes and Efficiency Measures
62
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Heat recovery from the boiler / steam generator smokes.
Heat from flue gases can be used to preheat boiler feed water in an economizer. By preheating the water supply, the temperature of the water supply at the inlet to the boiler is increased, reducing the amount of heat necessary to generate steam thus saving fuel.
Steam systems 5% Low - Low/Medium 2 - 4 years
Improvement of insulation of water / steam pipes.
Steam systems
up to 3% of thermal consumption up to 1% of electric consumption
Variable 1 years
Adoption of high efficiency boilers / steam generators.
Steam systems
from 0 to 4% of factory thermal consumption (in Italy) and up to 20% in disadvantaged backgrounds
Medium/High Medium
Condensates recovery in steam system.
Steam systems up to 5% Variable 1 years
Installation of cogeneration plant.
Steam systems
0% (no energy savings, but efficiency at the country level and economic saving for the company)
High Medium/Long
SET – Production Processes and Efficiency Measures
63
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Reduce excess combustion air to minimum by CO2/O2 measurement.
Steam systems on average 2,3% of factory thermal consumption
Low < 1
Maximise completeness of combustion by Soot/CO measurement.
Steam systems < = 1% of factory thermal consumption
Low < 1
Maintain boiler cleanliness (soot/scale) by monitor for rise in flue gas temperature.
Steam systems < = 1% of factory thermal consumption
Low Short
Repair (replace) boiler and feedwater tank insulation.
Steam systems 6% - 26% of boiler energy use
Low/Medium Short
Replace steam traps with sensor controlled magnetic valves (Condensate output on demand with minimum loss of fresh steam.).
Steam systems on average 1,5% of factory thermal consumption
Medium Medium
Insert valves to isolate "periodic-use" items in steam system.
Steam systems < = 1% of factory thermal consumption
Low/Medium Medium
Remove/isolate "dead-legs" and redundant pipework of steam distribution system
Steam systems < = 1% of factory thermal consumption
Low/Medium Medium
SET – Production Processes and Efficiency Measures
64
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Eliminate uneconomic “hot standby” periods, maintain heat supply only if absolutly necessary.
Steam systems
Variable A typical value is 1,1% of factory thermal consumption
Slight Short
Demand matching for steam generation.
A boiler is more efficient in the high-fire setting.
Steam systems < 2
Boiler allocation control for steam generation.
Systems containing multiple boilers offer energy-saving opportunities by using proper boiler allocation strategies. This is especially true if multiple boilers are operated simultaneously at low-fire conditions.
Steam systems
Flue shut-off dampers for steam generation.
Where boilers are regularly shut down due to load changes, the heat lost to the chimney can be significant. A solution to stop this loss of hot air is to fit fully closing stack dampers, which only operate when the boiler is not required. Another alternative is to fit similar gas tight dampers to the fan intake (CADDET, 2001).
Steam systems
SET – Production Processes and Efficiency Measures
65
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Maintenance of steam system.
In the absence of a good maintenance system, the burners and condensate return systems can wear or get out of adjustment.
Steam systems up to 10% of boiler energy use
The establishment of a maintenance schedule for boilers has an average payback time of 0,3 years (U.S. DOE-IAC, 2006).
Optimization of boiler blowdown rate.
Steam systems
Recovery of heat from boiler blowdown.
Steam systems
The use of heat from boiler blow down on average has payback period of 1,6 years (U.S. DOE-IAC, 2006).
Proper pipe sizing for steam distribution plant.
Steam systems
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66
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Reduction of distribution pipe leaks in steam plant.
Steam systems
On average leak repair has a payback period of 0,4 years (U.S. DOE-IAC, 2006).
Repair leaks in vacuum pipework.
Vacuum systems
Variable < = 1% of factory electrical consumption
Low Short
Use a central vacuum system with variable speed and pressotatic control and with several delivery points equipped with dampers.
Vacuum systems
< = 1% of factory electrical consumption
Medium/High Medium/Long
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67
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Use dedicated vacuum systems in machines with low work regime or geografically offset from central system. Applies to machines with frequent changes, variable workhours and/or far from centralized system. if all machines suffer from such variancy, dedicated systems are more efficient than centralized ones.
Vacuum systems
Variable < = 1% of factory electrical consumption
Variable Variable
Adoption of solar thermal collector.
from 0 to 4% of thermal consumption for building heating
Low Short
Replacement of fossil fuels with renewable fuels.
0% (no energy savings, but efficiency at the country level and economic saving for the company)
Variable Variable
Replacement of electrical heater with fire heater.
from 0 to 1% of overall thermal consumption
Variable Variable
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68
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Installation of trigeneration plant.
0% (no energy savings, but efficiency at the country level and economic saving for the company)
High Long
Switch off the machines and turn off the lights during the lunch break.
< = 1% of factory electrical consumption
Negligible Immediate
Establish Energy Monitoring and Energy Management System.
Develop and implement a system to monitor the energy consumption in the enterprise. Establish an Energy Management System (ofthe the easiest way is to integrate it into existing quality management systems). Set up the sensors, which are needed to monitor the imporrant consumptions.
Variable Variable Medium/High Varible
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69
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Identify excess non-variant consumption and turn off unneeded capacity.
Analyse the relation between consumption and production output. You can do this using the SESEC-Benchmark Tools. In general the energy consumption consist of a fixed part (like heating of buildings, lighting of offices) and a variable part, depending on the utilization of machines. A high fixed part may be reduced. A curve which increases more than linear might hint some production-planning optimizations potentials. It might be necessary to have a look at the departments seperately.
Variable < = 1% of electrical and thermal consumption
Variable < = 1% of electrical and thermal consumption
Slight Varible
Raise awareness of energy saving in all workers.
Train all staff to operate manual controls, to watch for energy saving opportunities, use posters, “switch-off”and “save-it” stickers as a tool of good housekeeping.
< = 1% of electrical and thermal consumption
< = 1% of electrical and thermal consumption
Low/Medium Short
Reduce the amount of ventilation by control optimization with a timer switch and/or occupancy sensor.
Variable < = 1% of factory electrical consumption
Low Medium
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70
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Use free-cooling whenever possible.
Avalilable when the outside temperature is lower than the inside and cooling is rquired, ex. cooling production plant in winter. Cold tab-water maybe used to cool machines and get waremd up at the same time.
< = 1% of factory electrical consumption
Variable Medium
Preheating boiler feed water with heat from flue gas (economizer)
Preheating water Steam systems 5% - 10% of boiler energy use
< 2
Replacement of nozzles with energy efficient mist nozzles in yarn conditioning room
Replacement of nozzles Heating/Air conditioning
31 MWh/year/humidification plant
1310€/humidification plant
<1
Installation of Variable Frequency Drive (VFD) for washer pump motor in Humidification plant
Installation of VFD Pumping systems
20 MWh/year/humidification plant
850€/humidification plant
<1
Replacement of the existing Aluminium alloy fan impellers with high efficiency F.R.P (Fobreglass Reinforced Plastic) impellers in humidification fans and cooling tower fans
Replacement of the existing Aluminium alloy fan
Fan systems 55,5 MWh/year/fan 500€/fan <1
SET – Production Processes and Efficiency Measures
71
Measure (Action) Measure description Applied for Fuel Saving Electricity Savings Investment Cost Payback period (years)
Installation of VFD on Humidification system fan motors for the flow control
Installation of VFD Fan systems 18-105 MWh/year/fan 1450-6660€/fan 1-2
Installation of VFD on Humidification system pumps
Installation of VFD Pumping systems
35 MWh/year/ humidification plant
5460€/humidification plant
2,7
Energy efficient control system for humidification system
Energy efficient control system
50 MWh/year/humidification plant
5615-9380€/humidification plant
2-3,5
Energy conservation measures in Overhead Travelling Cleaner (OHTC)
Energy conservation measures
5,3-5,8 MWh/year/OHTC 140-750€ OHTC 0,5-2,5
Energy efficient blower fans for Overhead Travelling Cleaner (OHTC)
Energy efficient blower fans Fan systems 2 MWh/year/fan 77€/fan <1
Improving the Power Factor of the plant (Reduction of reactive power)
Improving the Power Factor 24,1 MWh/year/plant 2540€/plant 1,8
Replacement of ordinary 'V-Belts' by Cogged 'V-Belts'
Replacement of ordinary 'V-Belts' by Cogged 'V-Belts'
1,5 MWh/yar/belt 9,4€/belt <1
SET – Production Processes and Efficiency Measures
www.euratex.eu/set 72/73
6 – Conclusions and Next Steps
The exercise resulting in this document allows the SET project team coordinated by
CITEVE to define textile processes and a list of energy efficiency measures, both
process specific and cross cutting, to be used in the SET project. Within these
efficiency measures, some newly developed technologies were also presented. The
amount of collected measures (105 process specific and 117 cross cutting) is far above
the targeted 60 of each.
The work performed during this task and the information collected and created are
very important for the upcoming project developments. The contents of this document
will be used in the development of ESET (Energy Saving and Efficiency Tool)
methodology and as guide of best practices for textile companies. Information
contained in this report is also expected to be used for training and dissemination
purposes at least throughout 2015 and 2016.
SET – Production Processes and Efficiency Measures
www.euratex.eu/set 73/73
7 - Reference
[1] Hasanbeigi, A., 2010. “Energy-Efficiency Improvement Opportunities for the Textile
Industry”. Berkeley, CA: Lawrence Berkeley National Laboratory
[2] CITEVE, 2012, EFINERG Project, “Plano sectorial de melhoria da eficiência
energética em PME – Sector têxtil e do vestuário”
[3] ITMA 2015, “General Regulations and Index of Products”
[4] CITEVE, 2012, Competitividade Responsável Project, “Guia de boas práticas para a
eficiência energética no Setor Têxtil e do Vestuário”
[5] Renovare Project, 2007, “Guia de boas práticas de medidas de racionalização de
energia (URE) e energias renováveis (ER)”
[6] United Nations Industrial Development Organization (UNIDO), 1992. “Energy
Conservation in Textile Industry-Handy manual”