LIST of FIGURES Table Symbol Etc
16
ABSTRACT The conventional method of power generation and supply to the customer is wasteful in the sense that only about a third of the primary energy fed into the power plant is actually made available to the user in the form of electricity. At Kozhikode Diesel Power Plant the eight diesel engines, producing power, gives out exhaust gas at high temperature, thus wasting heat. So a waste heat recovery system will be profitable and it’s also energy conservation. Here I suggested a waste heat recovery system with the intention of producing power in the form of electricity and will look into, what all are the major requirement for this system. The major requirements like heat exchanger is designed to produce steam from exhaust waste gas, steam turbine is selected to get rotary power by utilizing steam and alternator is designed to convert rotary power to electricity and an approximate economic analysis done to know the payback period and profit. By this waste heat recovery system with the investment of 13 crore, which will be paid back within 2.5 year, there will be a 5 crore profit every year after payback period. Considerable amount of waste heat can be utilized and thus energy can be conserved. Heat exchanger is designed to produce 350 0 C 11 bar steam and
Transcript of LIST of FIGURES Table Symbol Etc
ABSTRACT
The conventional method of power generation and supply to the customer
is wasteful in the sense that only about a third of the primary energy fed into the
power plant is actually made available to the user in the form of electricity. At
Kozhikode Diesel Power Plant the eight diesel engines, producing power, gives
out exhaust gas at high temperature, thus wasting heat. So a waste heat recovery
system will be profitable and it’s also energy conservation.
Here I suggested a waste heat recovery system with the intention of
producing power in the form of electricity and will look into, what all are the
major requirement for this system. The major requirements like heat exchanger is
designed to produce steam from exhaust waste gas, steam turbine is selected to get
rotary power by utilizing steam and alternator is designed to convert rotary power
to electricity and an approximate economic analysis done to know the payback
period and profit.
By this waste heat recovery system with the investment of 13 crore, which
will be paid back within 2.5 year, there will be a 5 crore profit every year after
payback period. Considerable amount of waste heat can be utilized and thus
energy can be conserved. Heat exchanger is designed to produce 3500C 11 bar
steam and a steam turbine of 1500kW 6000 rpm single stage is selected and an
alternator is designed to produce 1.5MW electricity by using the rotary power
from steam turbine. By utilising software we can easily get approximate required
parameters for heat exchangers. Software used for iteration purposes in steam
turbine selection also makes turbine selection easy. As the plant itself producing
electricity, the control and transport of produced electricity by waste recovery will
be simplified.
ACKNOWLEDGEMENT
First of all I would like to thank the Sovereign Almighty who is taking
care of me always and whose blessings have helped me to complete the thesis in
the best way I can.
I express my sincere thanks and deep sense of gratitude to Head of
department T Krishna Kumar. Also I express my sincere thanks to Assistant
Professor A.K. Mubarak, for his support, motivation and having guided me all
through. I also thank other professors K.K Ramachandran, Jayee K Varghese &
E.C Ramakrishnan for their suggestions throughout this thesis work. I sincerely
thank Damodaran, Assistant Mechanical Engineer at Kozhikode Diesel Power
Plant for his expert practical advice in this thesis work.
I thank all the teaching and non teaching staffs, my classmates and friends
for sharing their knowledge and valuable suggestions.
LIST OF CONTENTS
No. Content Name Pg.No
CHAPTER 1- INTRODUCTION 11.1 Cogeneration 11.2 Profile of Plant 11.3 Need for cogeneration 2
CHAPTER 2 – LITERATURE SURVEY 321 Cogeneration Technology 3
CHAPTER 3 – DESIGN OF HEAT EXCHANGER AND ALTERNATOR, SELECTION OF STEAM TURBINE AND ECONOMIC ANALYSIS
6
3.1 Introduction to shell and tube heat exchanger 73.2 Design of heat exchanger 83.2.1 Rating the preliminary design 183.2.2 Shell side heat transfer and pressure drop 203.2.3 Shell side heat transfer coefficient 203.2.4 Shell side pressure drop 223.2.5 Tube side heat transfer coefficient 233.2.6 Tube side pressure drop 253.2.7 Effectiveness of Heat exchanger 333.3 Software based design of heat exchanger 343.4 Introduction to steam turbine 413.4.1 Steam turbine 413.4.2 Steam turbine working 423.4.3 Impulse and reaction turbine 433.4.4 Comparison of impulse and reaction turbines 443.4.5 Steam turbine staging can vary 453.4.6 Single valve and multivalve 463.4.7 Single stage and multistage 463.4.8 Shortcut graphical method of turbine selection 463.4.9 Selection of single valve single stage steam turbine for the
purpose55
3.4.10 Selection of single valve multistage steam turbine for the purpose
60
3.5 Basic nozzle design 683.6 Basic design of turbine blade 693.7 Single arc method of blade profile design 713.8 Introduction to alternator 743.9 Design of alternator 753.9.1 Specific Loading 763.9.2 Flux density in air gap 783.9.3 Permeability 793.9.4 Reluctance and permeance 803.9.5 Magnetic motive force 803.9.6 Gilbert 80
3.9.7 Length of air gap 803.9.8 Whirling speed of rotor 843.9.9 Number of phases 853.9.10 Single layer winding 873.9.11 Eddy current loss 893.9.12 Leakage coefficient 953.9.13 Designed values of alternator 1003.10 Economic analysis 101
CHAPTER 4 – RESULTS AND DISCUSSIONS 103CHAPTER 5 – CONCLUSIONS 110BIBLIOGRAPHY 111
LIST OF TABLES
No. Table Name Pg.No
3.2 (a) TEMA design fouling resistance for industrial fluids 103.2 (b) Fouling resistance for water 103.2 (c) Dimensional data for commercial tubing 113.2 (d) Typical film heat transfer coefficient for shell and tube heat
exchangers15
3.2.5 Correlations for fully developed turbulent forced convection through a circular duct with constant properties
24
3.2.6 (a) Tube shell layouts (tube counts) 273.2.6 (b) Properties of water 283.2.6 (c) Wall temperature properties 293.3 Manual and software calculated values 393.4.8 (a) General Specifications for simple single stage steam turbines 493.4.8 (b) Approximate dimensions of simple single-stage steam
turbine49
3.4.8 (c) Temperature of dry and saturated steam 533.9.1 Value of specific loading with respect to output of AC
generator77
3.9.7 (a) Approximate values of apparent air gap density 813.9.7 (b) Distribution factor w.r.t no of slots per pole per phase 833.9.13 Designed values of Alternator 100
LIST OF FIGURES
No. Figure Name Pg.No
2.1.1 Steam turbine based cogeneration system 43.1.1 Constructional parts and connections 83.2 (a) Schematic sketches of most common TEMA shell types 93.2 (b) Tube layout 113.2 (c) Standard shell types and front end and rear end head types 123.2 (d) Plate baffle types 133.2.1 Rating program of heat exchanger design 193.2.3 Square and triangular pitch tube layouts 213.2.7 Designed heat exchanger showing dimensions 343.4.1 (a) Steam turbine showing main outer parts 413.4.1 (b) Longitudinal schematic section of typical steam turbine 423.4.1 (c) A simple schematic representation of steam showing the
variation in velocity and pressure as the steam pass through nozzle and blades
42
3.4.2 (a) A schematic section of an impulse turbine with a two row velocity compounded stage
43
3.4.2 (b) A longitudinal schematic section of an impulse turbine with three pressure stages
43
3.4.3 (a) Impulse and reaction turbine 433.4.3 (b) Nozzles and diaphragms 443.4.5 Stages of steam turbine 453.4.8 (a) Simple mollier diagram 463.4.8 (b) Mollier diagram 473.4.8 (c) Mollier diagram showing determination of theoretical
steam rate47
3.4.8 (d) Base steam rates of single valve single stage steam turbine 560 kW
50
3.4.8 (e) Base steam rates of single valve single stage steam turbine 1050 kW
50
3.4.8 (f) Base steam rates of single valve single stage steam turbine 1850 kW
50
3.4.8 (g) Base steam rates of single valve single stage steam turbine 2600 kW
51
3.4.8 (h) Base steam rates of single valve single stage steam turbine 2250 kW
51
3.4.8 (i) Mechanical losses of valve and stage single steam turbine 560 kW
51
3.4.8 (j) Mechanical losses of valve and stage single steam turbine 1050 kW
52
3.4.8 (k) Mechanical losses of valve and stage single steam turbine 1850 kW
52
3.4.8 (l) Mechanical losses of valve and stage single steam turbine 2600 kW
52
3.4.8 (m) Mechanical losses of valve and stage single steam turbine 2250 kW
53
3.4.8 (n) Superheat correction factor 533.4.8 (o) Inlet size requirements for single valve, single stage steam
turbines54
3.4.8 (p) Exhaust size requirements for single valve, single stage steam turbines
54
3.4.9 (a) CYR base steam rates of single valve single stage steam turbine 1850 kW
58
3.4.9 (b) CYR mechanical losses of single valve single stage steam turbine 1850 kW
58
3.4.9 (c) Approximate dimensions of simpler single stage turbine of frame CYR
59
3.4.9 (d) Presently available single stage steam turbine from Elliot’s Company
60
3.4.9 (e) Longitudinal schematic diagram of steam turbine shown in Fig 3.4.9 (d)
60
3.4.9 (f) Selection charts, three stages, single valve turbines (condensing) MODEL 2E2
60
3.4.9 (g) Selection charts, five stages, single valve turbines (condensing) MODEL 2E4
61
3.4.9 (h) Selection charts, eight stages, single valve turbines (condensing) MODEL 2E7
61
3.4.9 (i) Selection charts, four stage, single valve turbines (non-condensing) MODEL 2E3
61
3.4.9 (j) Selection charts, five stages, single valve turbines (non-condensing) MODEL 2E4
62
3.4.9 (k) Selection charts, four stages, single valve turbines (non-condensing) MODEL E4
62
3.4.9 (l) Selection charts, five stages, single valve turbines (condensing) MODEL SB5
62
3.4.9 (m) Selection charts, three stages, single valve turbines (condensing) MODEL SB4-3
63
3.4.9 (n) Inlet nozzle sizing for single valve, multi stage steam turbine
64
3.4.9 (o) Exhaust nozzle sizing for single valve, multi stage steam turbine
64
3.4.9 (p) Dimensions and weights of typical single valve, multistage steam turbine
65
3.4.9 (q) Selection charts, four stage, single valve turbines (non condensing)
66
3.4.9 (r) Dimensions of selected multistage steam turbine 673.4.9 (s) Elliot’s presently available multistage steam turbine 683.4.9 (t) Longitudinal sectional diagram of steam turbine shown in
Fig 3.4.9 (s)68
3.5 Simple nozzle section 683.6 (a) Velocity triangle on blade of steam turbine 693.6 (b) Velocity diagram for the approximate chosen blade
construction70
3.7 (a) Single arc blade profile design 713.7 (b) Designed profile of blade 723.8 (a) Alternator main parts 743.8 (b) Stator and rotor 743.9 (a) Vector diagram showing voltage relations in Y-connected
three phase generator76
3.9.9 Single phase, two phase and three phase armature winding 863.9.10 (a) Three phase, single layer winding; three slots per pole per
phase87
3.9.10 (b) Three phase, single layer winding; four slots per pole per phase
87
3.9.10 (c) “Developed” section through stator and rotor teeth of 1500 KVA turbo alternator
89
3.9.11 (a) Armature stampings of 1500 k.v.a turbo alternator 913.9.11 (b) Losses in armature stampings 923.9.12 (a) Rotor of four pole turbo alternator with radial slots 953.9.12 (b) Flux lines entering toothed armature 973.9.12 (c) Tooth densities in terms of air gap density 1500 k.v.a turbo
alternator97
LIST OF SYMBOLS AND ABBREVIATIONS
Heat Exchanger
Th1 Exhaust gas inlet temperature
Th2 Exhaust gas outlet
temperature
Tc1 Water inlet temperature
Tc2 Water outlet temperature
ṁ Mass flow rate of water
Cp Specific heat capacity of
water at constant pressure
Q Heat transferred between two
fluids
ho Shell side heat transfer
coefficient
hi Tube side heat transfer
coefficient
Uf Overall heat transfer
coefficient with fouling
resistance
Uc Overall heat transfer
coefficient with clean surface
lm Logarithmic mean
cf Counter flow
Af Required area with fouling
resistance
Ac Required area with clean
surface
Ao Total outer surface area of
tubes
do Outer diameter of tubes
di Inner diameter of tubes
Ds Shell diameter
Nt Number of tubes
L Length of tube
CTP Tube count calculation
constant
CL Tube layout constant
PR Tube pitch ratio
De Equivalent diameter
K thermal conductivity
Gs Shell side mass velocity
Re Reynolds number
h heat transfer coefficient
As Bundle cross flow area
∆ps Shell side pressure drop
∆pt Tube side pressure drop
Nb Number of baffles
f Friction factor
Pr Prandtl Number
OD Tube outer diameter
ID Tube inner diameter
B Baffle spacing
Np Number of tube pass
Tb Bulk mean temperature
ρ Density
μ Dynamic Viscosity
Tw Wall temperature
At Heat transfer area based on
the inside surface area of
tubes
um Average velocity inside tubes
U Overall heat transfer
coefficient
C a) Clearance b)Heat Capacity
Steam Turbine
TSR Theoretical steam rate
h Enthalpy
SR Steam rate
D Pitch diameter
N Speed
Va Inlet velocity to nozzle
Vb Outlet velocity of nozzle
J Joules constant
D1 Diameter at outlet of nozzle
g Acceleration due to gravity
u peripheral velocity of blades
V1 Velocity at outlet from nozzle
U1 Steam velocity relative to
blades at inlet
U2 Steam velocity relative to
blades at outlet
V2 Absolute velocity of steam at
outlet from blades
α Jet angle
β1 Inlet angle of blades
β2 Outlet angle of blades
Va1 Axial component of velocity
at inlet of blades
Va2 Axial component of velocity
at exit of blades
Vw1 Whirl component of velocity
at inlet of blades
Vw2 Whirl component of velocity
at inlet of blades
Vw Sum of whirl components of
velocity at inlet and outlet
ρ Radius
Alternator
p Number of poles
f Frequency
N Speed
u peripheral velocity rotor
D1 Internal diameter of armature
D Diameter of rotor
Ea Phase voltage
Ia Armature current
E Line voltage
I Line current
W Output power
E Terminal Voltage
q Specific loading
τ pole pitch
(SI)a Armature amp-turns per pole
ɸ Magnetic flux
B Flux density
Bg Flux density in the air gap
l Length
m.m.f Magnetic motive force
δ Length of air gap
Z Number of inductors in series
per phase
λ Slot pitch
K Distribution factor
la Axial length of armature core
ln Net length of iron in the
armature core
∆ Current density
t Tooth density
Rd Net radial length
R Resistance
m Circular mills
l ” Length expressed in inches
ϕa Useful flux
ϕl Leakage flux
Bs Density in the slot and air
spaces
δ Length of actual air gap tooth
top to pole face
d Depth of armature slot
Bt Actual tooth density
μ Permeability
