Chemical Boiler Water Treatment

8/16/2019 Chemical Boiler Water Treatment

1/299

1


2/299

1

Low and Medium Pressure Boilers


3/299

Purposes of Steam Generation

« Fuel heating

« Comfort heating and cooling

« Cargo heating« Tank cleaning

« Steam driven equipment

« Propulsion on steam ships


4/299

Fire Tube Boiler

Designed with

hot gases

in the tubes andwater/steam

outside the tubes

on the shell side

h hh hh h hh hh h hh hh

Steam Outlet

Sludge Feedwater

Blowdown

FurnaceTube


5/299

Water Tube Boiler

Designed withwater/steam in the

tubes and hot

gases outside

the tubes in

the combustionchamber

Steam Drum

Saturated Steam

Continuous Blowdown

Hot Gases

Waterwall(Risers)

Downcomer Tubes

Bottom Blowdown

Feedwater


6/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer

Distilled Water Tank

Seawater Inlet

HeatExchanger

Main Steam While in Port

Condensate Return

DistilledWater

Feedwater

FeedPump

Distilled Water Makeup

Boiler Water Boiler Water

Boiler Water

Boiler Water

CirculatingPump

RecirculatingFeedwater

Main Steam While at Sea

MakeupPump

Evaporator

Pre-Boiler

Boiler

After-Boiler

Simple Motor Vessel System


7/299

The Purpose of an Effective Boiler Water Treatment Program

« Minimize corros ion process

« Prevent formation of scale and deposits onheat t ransfer sur faces

« Maintain high level of s team purity« Maintain maximum equipment efficiency

« Maintain lowest overall operating cost


8/299

Minimizing Boiler Water Related Problems

• Starts with high qualitydistilled makeup water –Less than 20 mmhos conductivity


9/299

4

Functions of Boiler Water Treatment

1. To inhibit the corrosion process throughout the system2. To render any scale forming constituents harmless in

the boiler water 3. To prevent carry-over of solids from the boiler to the

power and heating plant system

Deposits

Scale

Corrosion

Waterside Related

Problems


10/299

Common Water Impuri ties From Scale

§ Calcium

§ Magnesium

§ Silica

Scale Formation


11/299

7

Principal water-related problems “ Scaling”

« Scaling is the formation of a crystalline, interlockedlayer of mineral substances on heat transfer surfaces

« Severe scaling normally occurs only within the boiler

« Typical scale formed are predominantly acarbonate/sulfate complex of Calcium and magnesium§ Calcium carbonate CaCO3§ Magnesium sulfate MgSO4


12/299

8

« If unchecked, scaling will lower boi ler efficiency

« It will retard heat t ransfer

« Eventually scale buildup will cause the tubes to overheat and rupture

« Scale can also accelerate corrosion

Phosphate/Alkali treatment

5CaCl 2 + 3Na 2 HPO 4 + 4NaOH = Ca 5 (OH)(PO 4 ) 3 +10NaCl + H 2 O

MgCl 2 + 2NaOH = Mg(OH) 2 + 2NaCl

Principal water-related problems “Scaling”


13/299

Calcium Formed Scales

Inadequate treatment Internal treatment/Sludge

Calcium Carbonate Calcium Phosphate- hydroxyapatiteCalcium Sulfate is normal fluidCalcium Silicate


14/299

10

Calcium Scale

Scanning Electron Micrographs


15/299

11

Solubility of CaSO4


16/299

Magnesium Formed Scales

Inadequate treatment Internal treatment/SludgeMagnesium hydroxide from Magnesium silicate - normal

insufficient phosphateand high alkalinity


17/299

13

Silica Formed Scales

Silicon Dioxide

a) Quartz

Ø Carried into boiler system as sand or precipitatesfrom boiler water

b) Amorphous

Ø Non-crystallized but aging can crystallize andform quartz

Combines with many elements to form

tenacious sil icate deposits


18/299

Scale Impedes Heat Transfer

Water

Scale

Steam

To Stack

BTUs

BTUs

BTUsBTUs


19/299

25

>1482 ° C >1482 ° C

Water side

Fireside

Clean tube Fouled tube

383

333

303293

° C

° C° C

Temperature Profile Across HP Boiler Tube

S

cale

° C

Bulk Water Temperature

Metal Surface

Temperaturewith Scale

353 ° CMetal SurfaceTemperatureno Scale

Fireside


20/299

16

Iron Deposits in Boiler SystemsOxides

a) Magnetite - passive, ideal protection

b) Hematite - rusts

Deposits In the Boiler Systems

Copper Deposits In Boiler SystemsMetal

Ø Improper acid cleaning

Ø Ammonia/dissolved oxygen corrosion of copper and copper

alloysØ Erosion in condensate or pre-boiler

Oxide

Ø Corrosion product from alloys in system


21/299

Sources of Deposits

Internal Boiler Inadequate Water

Water Conditioning TreatmentCalcium phosphate Calcium carbonate

Magnesium silicate Calcium sulfateMagnesium Calcium silicate

hydroxide Iron oxide

Internallyformed

deposits

Process Contaminants(organics and inorganics)

Feedwater

MudDrum

Feedwater hardness

Condenser leakage

Cooling water treatmentRaw water leakage

Boiler

Corrosion products fromcondensate and feedwater

systems (iron/copper)

SteamDrum


22/299

20

Effects of Deposits on Heat Transfer Loss

0 1 2 3 4 5 6 7 8

.24

.20

.16

.12

.08

.04

% LOSS OF HEAT THROUGH DEPOSIT FORMATION

D E P O S I T T H I C K N E S S C M


23/299

21

Deposits Impede Heat Transfer

Scale and Iron Oxide Mixtures

Porous deposits trap water resultingin under deposit corrosion


24/299

22

Heavily Scaled-Tube

Prone to Under-Deposit Corrosion


25/299

Deposits Impede Heat Transfer

Scale and Iron Oxide Mixture

Porous deposits trap water resultingin under deposit corrosion

Scale and Oil Mixture


26/299

26

Blistering

Smooth Uncracked Blister Failure Has NotOccurred Yet


27/299

Blistering


28/299

30

Principal water-related problems - “ Corrosion”

4 main categories of corrosion which will damage a

boiler/feed system if left unchecked are :

Ø Mineral acid corrosion - mostly in boiler

Ø Carbonic acid corrosion - mostly in the condensate

Ø Oxygen corrosion -most severe in boiler

Ø Differential concentration (under deposit corrosion) - mostsevere in the boiler


29/299

31

Principal water-related problems - Mineral acid corrosion

Ø Seawater ingress, condenser in leakage and/or distiller

carryover creates mineral acids in the boiler

Ø Mineral Acid corrosion

Fe + 2HCl = FeCl2 + H2

Maintain “P” alkalinity between 100 -150 ppm and “T” alkalinity less than

2 “P” alkalinity or pH 10.8 - 11.0


30/299

34

RELATIONSHIP BETWEEN P-ALKALINITY AND T-ALKALINITY

Phenolphthalein Alkalinity

Ø P-Alkalinity - includes the titration of all hydroxyl ions and one-half of thecarbonate ions

Total alkalinity

Ø T-Alkalinity - is a continuation of titration after the “ P-Alkalinity” has been

determinedØ The titration determines bicarbonate formed by conversion carbonate to

bicarbonate in the “P-Alkalinity” titration and/or any bicarbonate originallypresent in the water.

THUS,

P = OH-

+ 1/2 CO3- -

T = OH-

+ CO3- -

2P = 2OH-

+ CO3- -

\ 2P - T = OH-


31/299

37

Acidity, Alkalinity and pH Ranges

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Free Mineral

Acidity (FMA)

CO2 escapes quickly intoenvironment

5000mg/l

500 50 5

Bicarbonate Alkalinity

Free CO2 Gas

Acidity

mg/l CaCO2

5 50 500 5000mg/l

OH Alkalinity

mg/l CaCO2

Carbonate Alkalinity

Hydroxyl Alkalinity

M e t h y l

O r a n g e

E n d p o i n t

N e u t r a l i t y

H = O H

“ M ”

P h e n o l -

p h t h a l e i n

E n d p o i n t

“ P ”

pH


32/299

36

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

High

Low

Rate of CorrosiveAction

pH ScaleAcidCaustic

AlkalinityNeutral Neutral at

Boiler Conditions

TheoreticalCorrosion

Rate

Corrosive ActionUnder Normal BoilerConditions

Effect of HighOxygen Content

General Wastage Pitting Attack Increased

Foaming

I s o

l a t e d P

i t t i n g

R e c o m m e n

d e

d A l k a

l i n

i t y

Effect Of pH On The Rate Of Corrosion


33/299

38

4.5

3.5

2.5

0 02 4 6 8 10

pH

5.6

1.5

12

0.5

14

a c

i d i

c f i l m

s t a

b l e f i l m

d i l u

t e a

l k a l i n e

f i l m

acid alkaline

AverageMetal Loss mm

per year

Corrosion Rate


34/299

35

Principal water-related problems - Carbonic acid corrosion

Ø Carbonic acid is formed when CO2 dissolve in thecondensate

Ø CO2 is generated by the thermal breakdown of

bicarbonates in seawater ingress

Ø Carbonic Acid corrosion

CO 2 + H 2 O = H 2 CO 3

Cu ++

+ H 2 CO 3 = CuHCO 3 + H +


35/299

39

Low pH Condensate Corrosion

Carbonic Acid Attack

Condensate System Corrosion


36/299

41

Carbonic Acid Corrosion

Low pH Corrosion


37/299

42

Principal water-related problems - Oxygen corrosion

Ø Direct corrosive attack on boiler steel by oxygen occurs bycathodic depolarization of electrochemical cells at the

metal/water interface

Ø Most low pressure systems subjected to atmospheric oxygen

ingress

Ø Keep cascade tank temperature as high as possible

Ø Reduce the remaining dissolved oxygen with an oxygenscavenger


38/299

43

Effects of Oxygen Corrosion

a) Most severe in boiler

b) Metal ions Precipitate as Oxides

c) By-corrosion products TransportedTo Boiler

d) Reduce Heat Transfer

e) Lower than rated capacity

f) Equipment Failures

g) Repair, and Replacement


39/299

45

Common Methods to Remove Oxygen

Ø Maintain hotwell temp as high as possiblewithout losing feed pump suction

Ø Deaerators remove most oxygen by thermal-mechanical means

Ø Efficient deaerators reduce oxygen to < 0.007ppm

Ø Use chemical oxygen scavenger to remove

remaining oxygen


40/299

47

12

8

4

0-1 21 43 66 88 110

Temperature in Degrees Centigrade

Oxygen Contentml per liter

Solubility Of Oxygen In Water

At Atmospheric Pressure


41/299

48

Corrosion rate,mm per year penetration

7.5

5.0

2.5

00 2 4 6 8 10

Oxygen, ppm

49°

C 32°

C

9° C

Effects Of Oxygen Concentrations

Mild effectat low temp.

Increasing temperature increases corrosion rate


42/299

50

Oxygen Corrosion

Ø Occurs in anypart of steam

generatingsystem

Ø Readilyrecognized by

sharp-edged pits


43/299

53

Air Oxygen Gas Phase

Water Oxygen Liquid Phase

- Cathode -

High O2

OH OH

Solid Phase

G a s

L i q u

i d

S o l i d

ProtectiveCoating

- Cathode -

+ Anode +

e ee

e

H

HO2

Porous Tubercle of

Corrosion Products

High O2

OH

O2

HFe (OH)3

Fe3O4

Fe(OH)2

Crater

Fe++

H+H+

H2 H2

Localized Iron Corrosion Or Pitt ing


44/299

55

Oxygen starved areacovered

by deposit is anodic

High oxygen areais cathodic

Under Deposit Corrosion

Local Corrosionq Potential differences

between areas on thesame metal

q Results from variation

in oxygen content


45/299

24

Profile View of Under Deposit Corrosion


46/299

57

Principal water-related problems - “ Sludge”

Ø Sludge are combination of suspended material in the water,and it includes:§ Loose corrosion products§ Insoluble mineral precipitates.§ Significant proportion of suspended material are

generated outside the boiler § Oil contamination

Ø Baked-on sludge” on heat transfer surface acts as a heatinsulator

Ø Excessive sludge loading from outside boiler may distortsthe relationship of suspended to soluble constituents of theboiler water

Ø This will render in-built program controls less effective

Liquid Coagulant - Sodium Carboxymethylcellulose to bringsludges to low point to be blown-down.


47/299

1

Low and Medium Pressure Boilers


48/299

Boiler Treatment Chemicals

Standard Boiler Water Treatment Program§ GC – Alkal in ity Treatment & Magnesium Hardness Treatment

§ Adjunct B – Calcium Hardness Treatment

§ SLCC-A – Condensate pH Treatment

§ Amerzine – Oxygen Scavenge Treatment

§ Liquid Coagulant – Sludge & Oil Treatment

Multi-function Treatment Program

§ AGK-100 + Amerzine or AGK-100 + Drewplex OX§ Drewplex AT + Drewplex OX or Drewplex AT + Amerzine


49/299

Successful Boiler treatment program

« Boiler make-up water should be dist illed or goodquality water

« Boiler samples for testing must be representative

« Simple and accurate test methods

« Control boi ler water and condensate treatmentwithin limit

« Regular blow down schedule in accordance with theboi ler makers recommendations


50/299

Sampling

Test resul ts are meaningful and useful only when the samples tested are representative of

the water in the system at the time of testing.

§ Boiler Water Sampling

§ Condensate and Feed water Sampling

Sampling procedure

§ Samples should be cooled to 250C through a sample cooler before testing

§ Al low sample s tream to run for 5-10 minutes to flush line before collect ion

§ If analysis is delayed, sample should be kept tightly capped in a clean sample bott le.

Sampling Procedure for boiler water

§ Sampling line is usually from steam drum. Sample cooler should be used

Sampling Procedure for condensate and feed water

§ Sampl ing l ines are located at§ Af ter condenser § Cascade outlet or from the suction or discharge of the feed water pump


51/299

Adjunct B : Calcium Hardness Treatment

« Di-sodium Phosphate

« To provide a phosphate reserve

« To precipitate calcium as calcium phosphate, asoft non-adherent sludge that can easily be

blow-down; .

« The carbonates, sulfates and other ions combinewith sodium and remain in solution


52/299

GC: Alkalinity & Magnesium Hardness Treatment

§ Sodium Hydroxide alkalinity

§ To raise the boiler water alkalinity, in order to maintain the hydroxyl ionconcentration in the optimum range for the formation of good protective

magnetite on the steel surfaces

è Fe + 2NaOH Na2FeO2 + H2

è Na2FeO2 + 4H2O 6NaOH + Fe3O4 + H2

§ And to help in the format ion of non-adherent sludge instead of scalewhen hardness enters the boi ler, It reacts with the bicarbonates and

chlorides of magnesium and calcium; to precipitate harmless non-

adherent sludge and sodium chloride which remains in solution

è MgCl2 + 2NaOH Heat Mg(OH)2 + 2NaCl


53/299

Hydroxide Alkalinity

Calcium Phosphate Magnesium Silicate

Soft non-adherent sludgeseasily removed by bottom blowdown

Hydroxyapatite Serpentine

Adjunct-B + GC / AGK-100 / Drewplex AT


54/299

SLCC-A : Condensate pH Treatment

« Morpholine including in SLCC-A, AGK-100 and Drewplex AT

« To prevent after boiler sections low pH corrosion. Theneutralizing amine neutralizes carbonic acid and raise thecondensate pH.

« OC4H4N + H2 CO3 OC4H9N.H2CO3

« To protect heating coil in fuel storage tank


55/299

AMERZINE: Catalyzed Hydrazine, oxygen scavenger

« To scavenge the residual dissolved oxygen

« N2H4+ O2 N2+ H2O

« It also reacts with Ferric Oxide (Fe2O3 ) to form blackmagnetite, Ferrous Oxide (Fe3 O4) which retardscorrosion

« It also converts the Cupric Oxide (CUO) on condenser

tubes to the protective Cuprous Oxide CU2O film« Disadvantage - identified as a Carcinogen


56/299

DREWPLEX OX : Catalyzed oxygen scavenger

« Accelerates rate of oxygen removal

« Enhances total system oxygen corrosion protection

« It also reacts with Ferric Oxide (Fe2O3 ) to form

black magnetite, Ferrous Oxide (Fe3 O4 ) whichretards corrosion

« Passivates feedwater & condensate metal surface

« Save to use« Contributes no dissolved solids


57/299

Polymer in DREWPLEX AT

Disperseu Polymers will be adsorbed onto flocculent particles

– Impart a like charge to the particles

– Reduces the tendency of the particles to combine

u Inhibits scale formation by dispersing it

u Making it easily blown down

u The polymers will prevent iron oxides that returned to the boilerfrom depositing

Crystal growth modification

u Polymers are adsorbed onto growing crystals

- Disrupt their lattice structure

- Retard the crystal normal growth pattern

u Resulting in soft, and less adherent scale

u Thus preventing dense build-up of crystalline scale on the

heating surfaces


58/299

LIQUID COAGULANT

LIQUID COAGULANT™ Reacts with the positive chargesand forms a protection over the oil droplet to keep it from

sticking to the metal surface

Oil Droplet Has Approximately

80% Negative Charge And 20%

Positive Charge


59/299

AT

Drewplex AT Boiler Water Treatment


60/299

AGK-100

AGK-100 Boiler Water Treatment


61/299

CASCADE Tank

§ Recommend to convert cascade tank into deaeratorwhich extract the dissolved gases by raising thetemperature to a level where they come out of solution.

§ Keeping cascade tank temperature around 80-90 °C toreduce level of dissolved gases.

§ Keeping cascade tank in closed condition to preventgases contacted with water and dissolved into water


62/299

Boiler Blow-down

§ Proper boiler blow-down procedures are essential to ensure theeffectiveness of any boiler water treatment program. It is of

primary importance.

§ Continuous (scum) blow-down from below the water level in thedrum or steam separator to reduce the TDS in the boiler water to

a desired level.

§ Bottom blowdown from the low points in the boiler primarilyremoves settled solids.

§ It is prudent to practice frequent bottom blow-down of shortdurations (10 - 12 seconds) to remove sludge at the low point of

the boiler.


63/299

Feedwater Quality

Good (


64/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer


HeatExchanger


Condensate Return

Feedwater

FeedPump



Boiler Water

Boiler Water

CirculatingPump



DREWPLEX ® AT Boiler Water Treatmentand DREWPLEX OX Corrosion Inhibitor

Sampling and Dosing


MakeupPump

1 DREWPLEX AT boiler water treatment andDREWPLEX OX corrosion inhibitor continuousdosing with BWT™ dosing system.

2

2 Feedwater DEHA sample point.Requires cooler.

3

Continuous blowdown sample point for hydrate alkalinity,phosphate and conductivity.Requires cooler.

4

Makeup water.

5

Condensate sample point for pH.5

43

For testingprogram click

here

1

Sample Cooler

Sample Cooler Feedwater


65/299

DREWPLEX ® AT Boiler Water Treatment and DREWPLEX OX Corrosion InhibitorDosing

BWT™ Dosing System

60 LiterPolyethylene

Tank

• Πυµπ ανδ τανκ σετ το χοντινυουσλψ δοσε

∆ΡΕΩΠΛΕΞ ΑΤ τρεατµεντ ανδ ∆ΡΕΩΠΛΕΞ ΟΞχορροσιον ινηιβιτορ.

• ΠΧΝ 0124−65−1

• 17 βαρ δισχηαργε πρεσσυρε ωιτη πολψπροπψλενε δοσινγηεαδ

Γραϖιτψ ∆οσινγ

Χοντρολ βψ φλοωµετερ

For testingprogram clickhere


66/299

Control Tests Frequency Control Limit Sample PointHydrate Alkalinity Daily 30-65 ppm Boiler water Neutralized Conductivity Daily 700 mmhos max Boiler water DEHA Daily 0.4-0.8 ppm Feedwater

Reference Tests Frequency Sample Point

Phosphate Daily Boiler water Hardness Weekly Feedwater Condensate pH Weekly Condensate

Motor Vessel (0-450 psig or 0-32 bar)

DREWPLEX ® AT boiler water treatmentand

DREWPLEX OX corrosion inhibitorTesting Program

Decision Tree


67/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer


HeatExchanger


Condensate Return

Feedwater

FeedPump



Boiler Water

Boiler Water

CirculatingPump



DREWPLEX ® AT Boiler Water Treatmentand AMERZINE ® Corrosion Inhibitor

Sampling and Dosing


MakeupPump

1 DREWPLEX AT boiler water treatment andAMERZINE corrosion inhibitor continuousdosing with BWT™ dosing system.

2

Continuous blowdown sample point for hydrate alkalinity,hydrazine, phosphate and conductivity.Requires cooler.

3

Makeup water.

4

Feedwater.

5


3

42

1

Sample Cooler


here


68/299

DREWPLEX ® AT Boiler Water Treatment and AMERZINE ® Corrosion InhibitorDosing



Tank

• Πυµπ ανδ τανκ σετ το χοντινυουσλψ δοσε

∆ΡΕΩΠΛΕΞ ΑΤ τρεατµεντ ανδ ΑΜΕΡΖΙΝΕ χορροσιονινηιβιτορ.

• ΠΧΝ 0124−65−1



here


69/299

Control Tests Frequency Control Limit Sample PointHydrate Alkalinity Daily 30-65 ppm Boiler water Neutralized Conductivity Daily 700 mmhos max Boiler water Hydrazine Daily 0.03-0.1 ppm Boiler water

Reference Tests Frequency Sample Point

Phosphate Daily Boiler water Hardness Weekly Feedwater Condensate pH Weekly Condensate

Motor Vessel (0-450 psig or 0-32 bar)DREWPLEX ® AT Boiler Water Treatmentand

AMERZINE ® Corrosion InhibitorTesting Program

Decision Tree


70/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer


HeatExchanger


Condensate Return

Feedwater

FeedPump



Boiler Water

Boiler Water

CirculatingPump



AGK ® 100 Boiler and FeedwaterTreatment

Sampling and Dosing


MakeupPump

1 AGK 100 boiler and feedwater treatment continuousdosing with BWT™ dosing system. Supplementwith AMERZINE corrosion inhibitor as needed.

2

2

3

Makeup water.

4

Feedwater.

5


Continuous blowdown sample point for hydratealkalinity, phosphate, hydrazine andconductivity.Requires cooler.

3

4


here

Sample Cooler

1


71/299



Tank

• Πυµπ ανδ τανκ σετ το χοντινυουσλψ δοσε ΑΓΚ−100

τρεατµεντ. Συππλεµεντ ωιτη ΑΜΕΡΖΙΝΕ ® corrosion

inhibitor as needed.

• ΠΧΝ 0124−65−1


AGK ® - 100 Boiler and Feedwater TreatmentDosing


here


72/299

Control Tests Frequency Control Limit Sample PointHydrate Alkalinity Daily 30-65 ppm Boiler water

Neutralized Conductivity Daily 700 mmhos max Boiler water Hydrazine Daily 0.03-0.1 ppm Boiler water

Reference Tests Frequency Sample PointPhosphate Daily Boiler water Hardness Weekly Makeup water Condensate pH Weekly Condensate

Motor Vessel (0-450 psig or 0-32 bar)

AGK ® -100 Boiler and Feedwater TreatmentTesting Program

Supplement as necessary with AMERZINE ® Corrosion Inhibitor.

Decision Tree

M i St Whil t S


73/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer


HeatExchanger


Condensate Return

Feedwater

FeedPump

Distilled Water Makeup Boiler Water

Boiler Water

Boiler Water

CirculatingPump



Standard Treatment withAMERZINE ® Corrosion Inhibitor

Sampling and Dosing


MakeupPump

1 ADJUNCT B™ phosphate boiler water treatmentand GC™ concentrated alkaline liquid slugdosing into bypass pot feeder.

2

3

4

Makeup water.

5

Feedwater.5

Condensate sample point for pH.

AMERZINE® corrosion inhibitor andSLCC-A™ condensate corrosioninhibitor continuous dosing into feedwater.

1

3Continuous blowdown sample point forphenolphthalein and total alkalinity, phosphate,hydrazine, chloride and conductivity.Requires cooler.

4

6


here

2

Sample Cooler

6


74/299

Standard Boiler Water Treatment with AMERZINE ® Corrosion InhibitorDosing



Tank

• Πυµπ ανδ τανκ σετ το χοντινυουσλψ δοσε ΑΜΕΡΖΙΝΕ

χορροσιον ινηιβιτορ ανδ ΣΛΧΧ™- A condensate

corrosion inhibitor.

• ΠΧΝ 0124−65−1


• Βψ πασσ ποτ φεεδερ το σλυγ δοσε Α∆ϑΥΝΧΤ Β™phosphate boiler water treatment and GC ™concentrated

alkaline liquid.

• ∆ιλυτε προδυχτσ ωιτη χονδενσατε.

BypassPot

Feeder For testingprogram click

here


75/299

Control Tests Frequency Control Limit Sample PointP Alkalinity Daily 100-150 ppm Boiler water T Alkalinity Daily


76/299

Hotwell

AuxiliaryBoiler

ExhaustGas

Economizer


HeatExchanger


Condensate Return

Feedwater

FeedPump

Distilled Water Makeup Boiler Water

Boiler Water

Boiler Water

CirculatingPump



Standard Treatment withDREWPLEX ® OX Corrosion Inhibitor

Sampling and Dosing


MakeupPump

1 ADJUNCT B™ phosphate boiler water treatmentand GC™ concentrated alkaline liquid slug dosinginto bypass pot feeder.

2

3

4

Makeup water

6

Condensate sample point for pH.

DREWPLEX® OX corrosion inhibitor andSLCC-A™ condensate corrosion inhibitorcontinuous dosing into feedwater.

1

3Continuous blowdown sample point forphenolphthalein and total alkalinity, phosphate,hydrazine, chloride and conductivity.Requires cooler.

3a

3a Feedwater DEHA sample point.Requires cooler.

4

6


here2

Sample Cooler

Sample Cooler

Feedwater


77/299



Tank

Standard Boiler Water Treatment with DREWPLEX ® OX Corrosion InhibitorDosing

• Βψ πασσ ποτ φεεδερ το σλυγ δοσε Α∆ϑΥΝΧΤ Β™phosphate boiler water treatment and GC ™concentrated

alkaline liquid.

• ∆ιλυτε προδυχτσ ωιτη χονδενσατε.

• Πυµπ ανδ τανκ σετ το χοντινυουσλψ δοσε∆ΡΕΩΠΛΕΞ ΟΞ χορροσιον ινηιβιτορ ανδ ΣΛΧΧ™- Acondensate corrosion inhibitor.

• ΠΧΝ 0124−65−1


BypassPot

Feeder For testingprogram clickhere


78/299

Control Tests Frequency Control Limit Sample PointP Alkalinity Daily 100-150 ppm Boiler water T Alkalinity Daily


79/299

DREWPLEX AT & OX Control Chart

DREWPLEX AT & OX C t l Ch t


80/299

DREWPLEX AT & OX Control Chart

New Boiler Treatment


81/299

New Boiler Treatment

Conditions:§ Mill scale and rust on water side of new boiler should be removed to prevent p itting.

§ New boiler water contains very high disso lved oxidation so lids and suspend material.It will deposi t on heating surface to retard heat transfer.

§ High frequency blowdown required to remove dissolved and suspend material. Water

and chemical consumption are high by continuous blowdown.§ Tube plate may have residual of emulsion o il or anti-rust coating.

Recommendation:

§ Before sea trial, boil ing out new boiler by chemical (3% LAC solut ion).

§ Af ter bo il ing out , fi ll water and chemical t reatment to prevent ox idation .

§ Af ter sea tr ial , boi ler water wi ll be contaminated by solid and material from pipingsystem. Recommend to drain all water and flush boiler and cascade tank by jet water.Fill water and chemical immediately to prevent oxidation. .

LAC B ili O t


82/299

LAC Boiling Out

New Boiler waterside

before chemical clean

New Boiler waterside

after chemical clean

B ili t N PO


83/299

Boiling out – Na3PO4

Before After


84/299

Di l E i S t C li


85/299

Three Main Diesel Engine Systems Require Cooling

« Engine Jacket

« Piston Areas« Fuel Valves

Diesel Engine System Cooling

Cooling Water System divided by 2 major systems

1. HT Cooling System

2. LT Cooling System


86/299

Minimizing Cooling Water Related Problems


87/299

• Starts with high qualitydistilled makeup water – Less than 20 mmhos conductivity

Minimizing Cooling Water Related Problems

Common Problems


88/299

« Mineral Scale

« Deposits

« Corrosion

Common Problems

Mi l S l


89/299

§ Hardness introduced into the system from seawater in-leakage orshore water makeup

•Calcium carbonate•Calcium sulfate

Types

•Hard scale insulates metal surfaces andimpedes heat transfer

•Equipment damage•Potential for under deposit corrosion•Localized overheating and metal failure

Consequences of Inadequate Treatment

•Use good quality distilled makeup water•Treat with polymeric antiscalants that

hold scale particles in suspension untilthey can be removed by bleed off

Minimization

• High heattransfer sections

Found In

Mineral Scale


90/299

TempGradient Across

1MMScale

1mm Mineral Scaleon Water Side

Clean Cylinder Wall

570o C

270o C

70o C

Temperature

Gradient Acr oss

25 mm liner

Temperature

Gradient

Acr oss

25 mm liner

Effect of Scale on Temperature of CYLINDER WALLS

CombustionSide

Combustion

Side

Water

Side

Water

Side

Deposits


91/299

§ An accumulation of suspended solids that can come from manydifferent sources

•True scale•Corrosion products•Oil contamination

•Bacteria contamination•Mixtures of above

Types

•Insulate metal surfaces and impede heattransfer

•Bacteria can form a biofilm•Equipment damage•Potential for under deposit corrosion•Localized overheating and metal failure

Consequences of Deposits Minimization

•Use good quality distilled water makeup•Treat with with polymeric antiscalants

that hold particles in suspensionuntil they can be removed by bleed off

Found In

•Oil in fuel valve area•Bio in cooler areas•Scale/corrosion in high

heat transfer areas

Deposits

Bacteria Contamination


92/299

« Biological growths enter coolingwater at head tanks or othersystem openings

« Growth destroy nitri te used forprotective mono-molecular film

« Growths insulate heat transfersurfaces

« Found in LT Cool ing WaterSystem.

Growth

Bacteria Contamination

Controll ing Bacteria Contamination


93/299

« Loss of ni trite or increase of nitrate may be indication ofcontamination

« Treat with microbiocide if detected

« Do not use shore water

« Do not use water that has been in contact with marinesanitation device vent

Controll ing Bacteria Contamination

Corrosion


94/299

Galvanic•Cavitation/erosion•Under deposit

•Low pH

Types

•Loss of metal•Equipment damage•Repair, replacement and labor costs

•Unscheduled outages

Consequences of Inadequate Treatment

•Gal-low temp areas•Cav/ero-high flow•Dep/pH-anywhere

Found In

§ Loss of metal through electrochemical reversion to its orig inalstate

Minimization

•Use good quality distilled water makeup•Treat with good scale and corrosion

inhibitor •Minimize dissimilar metals•Ground electrical equipment•Reduce or change water flow•Use more resistant metals•Redesign cooling water circuits

Corrosion

Galvanic Corrosion


95/299

§ The action between different metals form a galvanic couple

Galvanic Corrosion

Galvanic Series Of Metals


96/299

Galvanic Series Of Metals

Gold and PlatinumSilver Chromium-Nickel-Iron (passive)Copper LeadTinBronzes

BrassesNickelStainless SteelChromium-Iron (active)CadmiumIron

ChromiumZincAluminumMagnesium

Cathode is the protected end

Anode is the corroded end

• Metals near the bottom of the

series act as anodes and suffer

corrosion when coupled with

metals near the top of the

series.• Galvanic couples of metals

close together in the series

usually corrode more slowly

than couples composed of

metals f rom the extreme endsof the series

Cavitation/Erosion Corrosion


97/299

« Appears as shallow pitting or gouging

« Occurs in areas with high f low rates and rapidpressure changes causing gas bubbles to be created

and then to collapse§ The col lapsing gas bubbles attack the metal

« Mechanical action§ Changes in water direction§ Induced vibrations

Cavitation/Erosion Corrosion

Cavitation


98/299

CoolingWater

Cylinder Liner

Sleeve

Magnitude of Deflection

(exaggerated for example)

CoolingWater

StaticCondition

During eachpower stroke

cylinder sleevedeflects in

the plane of the piston rod/crank rotation

Bubbleformationand sleevedeflectionreturningto normal

Bubblescollapse

and energyis releasedcausing

metal damage

NormalBubble

Directionof energy

releasewhen thebubble

collapses

Cavitation

Cavitation


99/299

Cavitation

Cavitation on

cylinder liner

Impingement


100/299

Impingement

cathode cathode

Protective coating is lost due to turbulenceand wants to reform.

Impingement

anode

Minimizing Corrosion


101/299

« Galvanic§ Minimize dissimilar metals in cooling water circui t§ Ground electrical generation equipment

« Cavitation§ Reduce or change water flow rate in localized areas§ Use more resistant metals§ Redesign of cooling water ci rcuits§ Apply protective chemical t reatment barrier

Minimizing Corrosion

LIQUIDEWT™ cooling water treatment


102/299

LIQUIDEWT cooling water treatment

« Nitrite-based for medium and slow speed engines

« Provides passivation corrosion protection with a thin,impervious fi lm of nitri te that minimizes the potential

between the anode and cathode areas thereby minimizingcorrosion and metal loss

« Contains alkalinity to protect against low pH corrosion

« Contains a polymer to keep scale in suspension« Contains multi-metal protection for non-ferrous metals

LIQUIDEWT


103/299

Sodium nitrite + multifunctional inhibitors

§ Liquid form - pH buffered

§ Compatible with anti-freeze materials

§ Control limits is 10,000-15,000 ppm

§ May be used for medium to large capacity systems

§ Initial dosage is 8 ltr/ton of water

§ Safe as heating source for evaporator

§ Contains scale inhib itor

§ Protects ferrous & non-ferrous metals

§ Simple (CWT) Titrets tests to check reserve

Controlling LIQUIDEWT™ cooling water treatment


104/299

« Weekly testing

« Easy to use ampoules

« Easy to use Control and Dosage Chartto modify treatment accordingly

« CWT Titret1 Test Kit§ Control between 1.2-1.8 units

§ Product code 0367-01-2

Controlling LIQUIDEWT cooling water treatment

Nitrite

1Registered trademark of CHEMetrics, Inc.

DREWGARD CWT


105/299

DREWGARD® CWT diesel engine cooling water treatment« Non-nitrite formula does not promote bacteria« Provides excellent aluminum protection for high speed engines« Provides passivation corrosion protection wi th a thin,

impervious fi lm of organic material

« Polymer keeps scale in suspension« Contains multi-metal protection for non-ferrous metals« Contains alkalinity to protect against low pH corrosion

DREWGARD CWT

Controlling DREWGARD® CWT treatment


106/299

Controlling DREWGARD CWT treatment

§ Weekly testing§ Easy to use ampoules

§ Easy to use Control and Dosage Chart

to modify treatment accordingly

§ Silica Ampoule Test Kit§ Product code 0376-01-3

§ Silica Dilut ion Kit§ Product code 1AA2805

§ Control at 350-450 ppm SiO2Silica

Testing for Chloride


107/299

§ Less than 100 ppm in system water § Less than 50 ppm in MAN B&W 4-stroke engines

§ Chloride LMP Test Ki t

§ PCN 0373-01-9

§ Sample Pretreatment§ PCN 0374-02-5§ Removes interference from non-ferrous corrosion

inhibitor

Testing for Chloride

Detecting Cooling Water Problems


108/299

§ If there is a sudden loss of treatment look for:§ System leakage§ Increased makeup requirement§ Presence of bacteria

§ If there is foaming look for:§ Oil contamination§ High nitrite reserve

§ If the chloride reading is high look for:

§ Salt water in-leakage§ Poor quality makeup water

Detecting Cooling Water Problems

Dosing Cooling Water Treatments


109/299

« Shot dose via by-pass potfeeder into main circulation

« Shot dose into head orexpansion tank

« Pump into main circulation

By-passpot feeder

Dosing Cooling Water Treatments

Cooling System Commissioning


110/299

g y g

§ Check

§ Clean by FERROCLEAN5% solut ion for 24 hours.

§ Drain and flushing .

§ Dose LIQUIDEWT

immediately.

Rust and deposit in piping system should be removed to stopoxidation and under deposit corrosion


111/299

High Purity Water


112/299

« Necessary for steam generation

« Makeup to diesel engine and cooling systems

« Special tank cleaning rinsing

« Domestic applications

g y

Evaporators


113/299

p

Well maintained and properlyoperated evaporators

reduce dissolved solidsto approximately

2 ppm

Seawater contains almost35,000 ppm dissolved solids

Heating Medium For Evaporation Process


114/299

g p

« Low-pressure steam

« Hot water § Diesel engine jacket water

Evaporation Process


115/299

p

« Heat is transferred to seawater under vacuum

« Resulting vapor is condensed into distil late

« Dissolved sol ids are left behind§ Accumulated and concentrated for overboard discharge

« Brine density needs to be limited§ As dissolved solids increase, the tendency to form scale on

heating surfaces also increases

§ Increase in solids would lead to increase in carryover anddisti llate purity would be affected

Evaporator Problems


116/299

Scale is introducedfrom seawater

True scale from inadequate treatmentCalcium CarbonateCalcium SulfateMagnesium Hydroxide

DepositsSludges formed from polymer treatmentCalcium CarbonateCalcium SulfateMagnesium Hydroxide

CorrosionNot usually found

p

Scale Decreases Evaporator Output


117/299

0

50

100

80

Time

TreatedUntreated Acid Cleaning

%

Design

Output

p p

Foaming and Carryover


118/299

§ High concentration of dissolved solids in brine§ Increases surface tension§ Vapor bubbles and gases are not released§ Bubbles burst and droplets containing concentrated salts go

into vapor spaces and are carried over into distil late

§ Organic substances may cause foaming

§ Minimize by proper management of the water level and

brine control

g y

Low Pressure Thin-Film Distiller


119/299

Condenser

Demister

Evaporator

Brine Ejector Orifice

Air Ejector

Over Board

Ejector PumpTo FreshWater Tank

ToBilge

Salinometer

ElectricPanel

Jacket Water

Sea Water

In

Out

Out

In

AMEROYAL ®

treatment

From Sea

FreshWater Pump

Evaporator Scale


120/299

Synthetic Polymers Inhibit Scale


121/299

§ Scale forming salts tend to stay in solution

§ Salts that precipitate are irregular in crystal shape

because of their molecular attachment to the polymer § Precipitates can not pack together to form scale

AMEROYAL® evaporator treatment


122/299

« Scale prevention§ Scale forming salts tend to stay in solut ion§ Salts that precipi tate are irregular in crystal shape

because of their molecular attachment to thepolymer

« Recommended for temperatures up to 100ºC

« Dosage is 30 mls per ton of disti llate produced

« Contains an antifoam§ Reduces surface tension of the brine§ Reduces water entrainment in the vapor

Removing Scale


123/299

AMEROYAL® evaporator treatment wil l remove exist ing

scale§ If scale is th ick and dense, on-line removal may take

considerable time

SAF-ACID™ descaling compound§ Use for off-line cleaning i f time does not permit on-line

cleaning§ Once heat transfer surfaces are clean, treat with AMEROYAL

evaporator treatment to prevent future scale buildup

Feeding Evaporator Treatments


124/299

§ Treatment solution must be fedcontinuously

§ Treatment must be fed before the

first heat exchanger

§ Use DREW FWG dosing system§ Tank and flowmeter § 0-200 cc/min flowmeter with control

valve§ 60 liter HPE tank

DREW™ FWGdosing system


125/299

System: seawater cooling


126/299

Problem:

§ Loss of heat exchanger efficiency

Cause:

§ Biological fouling

Solution:

§ Seawater cooling treatment

Simplified Sea Water Cooling System


127/299

Primary cooling and

various heat exchangers

Evaporators

Fire fight ing system

Ballast uses

Tank c leaning

Primary Sea Water Cooling System Problem


128/299

• Deposits orencrustation’s ofmarine micro andmacro-biologicalgrowths

• Left unchecked seagrowths can completelyplug inlet area of seachests, strainers,

condensers, heatexchanger water boxes

Plate Cooler Bio-Fouling


129/299

Detecting Seawater Fouling


130/299

• Seawater growths act asheat transfer barriers

• Check heat transfer flow – Is output normal? – Are heat exchanger

temperatures normal?


131/299

Seawater treatment dosing system


132/299

SWT Dosing Unit Educator Dosing Unit

AMERSPERSE 280


133/299

Biocide action

§ kills marine growth

Dosage

§ 1.5 ltr/100 ton/hr over 100 mins.

Frequency

§ 2 x week - coastal,

§ 1 x week in open ocean

Pre-cleaning - required

pH - 11.5

Odor - Hydrogen sulfide, pungent

DREWSPERS SWD


134/299

Dispersing action§ Removes sl ime layers; not possible for marine growth to adhere

and mature

Dosage

§ 0.6 ltr/100 ton/hr over 60 minutes

Frequency:

§ 2 x week - coastal

§ 1 x week - open ocean

Precleaning - required

§ Odor - slight ly ammoniac, pleasant

Dosage Schedule


135/299

DREWSPERSE® SWD seawater dispersant

Harbor Anchorage & Shelf Zone

Deep Sea Zone

Dose Every Third Day

Starting And Finishing

At Point B

Dose Once

Mid Voyage

To Maintain Flow

Dose Every

Third Day

Starting And

Finishing

At Point C A B C D

Feeding systems


136/299

§ Tankset gravity feed systems

§ Eductor feed system

§ Metering pump


137/299

Fuel quality & problems

Crude Oil Models


138/299

Group

Paraffinic

Naphthenic(>4 carbon)

Asphaltic

Cn + H2n + 2

CnH2n

CnH2n - 6

H H H H H H

H C C C C C C H

H H H H H H

H H

Low Sulphur

Low Ash

High Wax Content

High Cetane

North Africa/Indonesia

Medium-to-High Sulphur

Medium Cetane

C Rings Saturated with H

Middle East/Alaska

High Asphaltenes

High Ash

Venezuela/Mexico

CCC

C

C C

CH CH

CH CH

CH CH

H H

H H

H HH H

H H

Hydrocarbon Structure General Formula

Energy of Combustion


139/299

« Hydrocarbons Burn with Oxygen:

• C + O2 CO2 7.8 Kcal/gm (14,000 btu/lb)• 2C + O2 2CO 2.2 Kcal/gm (4,000 btu/lb)• 2H2 + O2 2HO2 17.1 Kcal/gm (30,000 btu/lb)• S + O2 SO2 2.2 Kcal/gm (4,000 btu/lb)

« Carbon - Hydrogen Ratio:• ΜΓΟ Χαρβον (70%) + Ηψδρογεν (30%) + Συλπηυρ (τραχε)

• ΗΦΟ Χαρβον (85%) + Ηψδρογεν (12%) + Συλπηυρ/Ιµπυριτιεσ

(3%)

Chemical Reaction Energy Produced

Fuel Standard: ISO 8217 - 2010


140/299

Fuel Standard: ISO 8217 - 2010


141/299

Summary - Important Fuel Properties


142/299

t Viscosity – Fuel Purchase Specification – Fuel Handling – Atomization – Ignition Quality Calculation

t Density – Water Separation – Ignition Quality Calculation

t Flash Point – Storage Safety

t Pour Point – Low Temperature Handling

t Carbon Residue – Smoke and deposits

t Asphaltene Content – Deposits – Particulates

u Ash Co n t e n t

– De p o si t su Va na d i u m

– Hi g h Te mp . Co r r o si o n

u Su l p h u r

– L u b e P r o p e r t i e s

– L o w Te mp . Co r r o si o n

u Wa t e r Co n t e nt

– He a t i ng Va l u e

u I g n i t i o n P r o p e r t i e s

– Smo o t h Op e r a t i o n

u Ca t a l y st Co nt e nt

– L i ne r We a r

– I nj e c t o r We a r

– F u e l P u mp We a r

Viscosity


143/299

The viscosity of fuel oil is a measure of itsresistance to flow.

u Te mp e r a t u r e = Vi sc o si t y

u Ch a ng e s i n v i sc o si t y f o r f u e l i s no t l i ne a r wi t h c h a ng e s

i n t e mp e r a t u r e

u Hi g h i nj e c t i o n v i sc o si t y i nc r e a se s f u e l d r o p l e t si z e

Ø I nh i b i t s f u e l - a i r mi x i ng

Ø R e su l t s i n i g ni t i o n d e l a y

Ø I nc r e a se s u nb u r ne d c a r b o n d e p o si t s

u Co mmo n mi sc o n c e p t i o n : “Lower viscosity fuels are better

quality than higher viscosity fuels”. Not True. Additional

blending often creates more incompatibility.

Density


144/299

u T h e d e nsi t y o f t h e f u e l wi l l d e t e r mi ne i t s a b i l i t y f o r wa t e

a nd se d i me n t se p a r a t i o n

u Use d t o c a l c u l a t e t h e i g n i t i o n q u a l i t y o f t h e f u e l ( CCAI )

u R e q u i r e d t o c a l c u l a t e t h e a mo u nt o f f u e l d e l i v e r e d ,

v e r su s t h e a mo u nt p a i d f o r

Ø F u e l i s r e c e i v e d b y v o l u me ( c u b i c me t e

Ø Bu t p a i d f o r b y i t s ma ss ( me t r i c t o ns)

Ø R e q u i r e s a c c u r a t e d e nsi t y f o r q u a nt i t y

Mass (Kg at 15o

C)Density =Volume (Cubic Meters)

}

Quantity Calculation (using Density)


145/299

2000 tons of 380 cSt ordered @ $500/t

Density on delivery receipt…..985 kg/m3

Actual Density(lab analysis)….975 kg/m3

Difference in Quantity..........….....20 tons

Shipowner overcharged.......…US$ 10,000

(0.985 - 0.975) x 2000 x $500 = overcharge

Water Content


146/299

Fresh water contamination is not a serious problem,provided it can be effectively removed from the fuel.

u Wa t e r i s g e n e r a l l y i nt r o d u c e d i nt o f u e l s f r o m l e a k i ng st e

c o i l s, t a nk c o nd e nsa t i o n o r i ng r e ss o f r a i n wa t e r t h r o u g h

u I SO 8 21 7 : 20 0 5( E ) f u e l st a nd a r d s a l l o w f o r wa t e r c o nt e n t

0 . 3% i n Di e se l F u e l a nd u p t o 0 . 5% i n He a v y F u e l Oi l .

u Hi g h wa t e r c o nt e nt r e p r e se nt s a l o ss i n b o t h mo ne y ( p a i d f o r

wa t e r no t f u e l ) a nd a v a i l a b l e e ne r g y ( wa t e r d o e s no t b u r n) .

u Se a wa t e r h a s e mu l si o n- f o r mi ng t e nd e n c i e s

Ø Di f f i c u l t t o r e mo v e wa t e r f r o m e mu l si o ns

Ø F u e l sl u d g e wi l l f o r m i n st o r a g e t a nk s

Ø So d i u m i n t h e f u e l wi l l c a u se c o r r o si o n p r o b l e m

Flash Point


147/299

The lowest temperature at which flammable vapors,

formed above the fuel, will ignite.

u M i ni mu m F l a sh P o i nt i s 60oC f o r M DO a nd HF O.

u M i ni mu m F l a sh P o i nt i s 4 3oC f o r M GO ( DM X g r a d e ) .

u Fuels received with a flash point below the minimum isin violation of Safety of Life at Sea (SOLAS). Correctiveaction should be taken immediately.

u F u e l s st o r e d a t t e mp e r a t u r e s b e l o w t h e i r f l a sh p o i nt ma y st i l

d e v e l o p f l a mma b l e v a p o r s i n t h e h e a d sp a c e o f c l o se d t a nk s.

u As a g e ne r a l r u l e , st o r e d f u e l s sh o u l d b e ma i nt a i ne d a t

l e a st 1 0oC b e l o w t h e i r f l a sh p o i nt .

Pour Point


148/299

The lowest temperature at which fuel oil will continue to flow.

Below this temperature, wax in the fuel will begin to separateout, reducing the oils ability to flow.

u I d e nt i f i e d a s 3oC a b o v e t h e t e mp e r a t u r e a t wh i c h t h e o i l c e a se

t o f l o w.

u I nc r e a se s v i sc o si t y wh e n b e l o w t h e p o u r p o i nt , ma k i ng p u mp i nd i f f i c u l t .( p u mp d a ma g e )

u P r e c i p i t a t i o n o f wa x f r o m f u e l s i n st o r a g e t a nk s wi l l r e q u i r

h e a t i ng t o a t e mp e r a t u r e a b o v e t h e p o u r p o i nt t o r e - l i q u e

( p o t e nt i a l h e a t e r f o u l i ng )

u P r e c i p i t a t e d wa x f r o m f u e l s wi l l a l soc l o g f i l t e r s.

u St o r e f u e l a t a mi ni mu m o f 5oC a b o v e P o u r P o i nt .

Fuel Storage Temperatures (Guideline)


149/299

Headspace

Fuel Oil

≈ ≈

≈ ≈ ≈ ≈ ≈

≈ ≈

≈ ≈ ≈

≈ ≈ ≈ ≈

≈ ≈

u Flash Pt. = 63oC

u Pour Pt. = 10oC

Fuel Analysis Storage temperaturerange between15oC and 53oC

u 5OC above Pour point

u 10OC below Flash Point

StorageGuideline}

Carbon Residue


150/299

The fuel’s Carbon Residue indicates the potential to formcoke or carbonaceous deposits during combustion.

u Hi g h c a r b o n r e si d u e f u e l s wi l l b e mo r ed i f f i c u l t t o b u r nc o mp l e t e l y ,

e sp e c i a l l y wh e n e ng i ne s a r e r u na t l o w l o a d.

u Unb u r ne d c a r b o n d e p o si t swi l l a c c u mu l a t e i n t h e c y l i nd e r s, o n

t u r b o c h a r g e r r o t o r s a nd i n t h e wa st e h e a t b o i l e r ( e c o no mi z e r )

u Unb u r ne d c a r b o n d e p o si t s c r e a t e ap o t e nt i a l f o r e x h a u st t r u nk

f i r e sa nd e x p l o si o ns. ( p o t e nt i a l t u r b o c h a r g e r d a ma g e )

u Ca r b o n d e p o si t sc o nt a i n a sh me t a l sr e su l t i ng i n c o r r o si v e d e p o si t s

u F u e l s p r o d u c e d f r o m t h et h e r ma l c r a c k i ng p r o c e ss(Visbreaking)have a higher Micro Carbon Residue (MCR).

Asphaltenes


151/299

Asphaltene Micelles

Very HighC/H Nucleus

Successively LowerC/H RatioSame C/H Ratio as

Continuous Phase (Maltenes)

u Complex hydrocarbon molecules with high carbon-to-hydrogen ratiou Precipitate from the fuel (incompatibility) causing fuel sludge

u Contribute to increased engine particulate emissions & deposits

u Molecular size from 1 micron to more than 100 microns

Composition of Combustion Particulates


152/299

Soot & OrganicCompounds

Water (w/Sulphate)

Sulphate

Heavy Metals59.0%

17.8%

22.2%

0.9%

257.24

77.61

96.79

3.95

ParticulateComposition mg/kWh

Total Particulate mass 100% = 0.436g/kWh

u Particulate composition for MAN B&W7L40/45 engine aboard a ferry shipburning 180 cSt fuel oil.CIMAC Congress - Copenhagen 1998

Due tocarbon residue& asphaltenes

Sediment


153/299

Inorganic matter such as grit, clay and sand containedin the fuel, expressed as “Total Sediment”.

u Se d i me nt wi l l c a u se sl u d g e i n u n st a b l e f u e l s.

u F i l t e r p l u g g i ng , h e a t e r f o u l i ng a nd p u r i f i e r o v e r l o a

u Se d i me nt c a n a l so c a u se we a r t o f u e l i n j e c t o r s.

u Si nc e r e si d u a l f u e l i s a wa st e p r o d u c t o f t h e r e f i ne r y ,

o f t h e c r u d e o i l se d i me nt a c c u mu l a t e s i n ma r i ne f u e l s.

u Se d i me nt c a n g e n e r a l l y b e r e mo v e d f r o m f u e l b y se t t l ii n st o r a g e t a n k s, f i l t r a t i o n a nd c e nt r i f u g i ng .

Purifier Overload


154/299

u High sediment, asphaltenes and incompatibility can lead topurifier overload and filter plugging

Ash Content


155/299

Fuel Ash content is the measure of the inorganic,non-combustible elements (metals) present in the fuel.

u Va na d i u m, so d i u m, c a l c i u m, ma g ne si u m, z i nc , l e a d , i r o n

a nd ni c k e l ; a s we l l a s, a l u mi nu m a nd si l i c o n (catalyst fines)

from the refining process.

u Ash a c c e l e r a t e s we a r t o f u e l p u mp s, i nj e c t o r s a nd c y l i nd e r

l i ne r s.

u Ash d o e s b u r n d u r i ng c o mb u st i o n, b u t f o r ms i no r g a ni c a sh

d e p o si t s o n e n g i ne e x h a u st v a l v e s a nd t u r b o c h a r g e r s.

u So me a sh d e p o si t s a r e h i g h l y c o r r o si v e ( v a na d i u m) .

Ash Melting Points


156/299

Ash ComponentVanadium trioxide

Vanadium tetroxideVanadium pentoxideSodium metavanadateSodium pyrovanadateSodium orthovanadateNickel orthovanadate

Ferric metavanadateFerric vanadateCalcium sulfateFerric sulfateMagnesium sulfateNickel sulfateSodium sulfateAluminum oxideCalcium oxideFerric oxideMagnesium oxideNickel oxide

FormulaV2O3V2O4V2O5Na2O V2O52Na2O V2O53Na2O V2O53NiO V2O5

Fe2O3 V2O5Fe2O3 2V2O5CaSOFe2(SO4)3MgSO4NiSO4NaSO4Al2O3CaOFe2O3MgONiO

••

••

••

Melting Pt. oC1970

1970675630640850900

8608551450

480 to Fe2O31125 to MgO840 to NiO

88020502572156528001990

Decomposes atDecomposes atDecomposes at

{Near exhaustvalve surfacetemperature

Ash Deposits


157/299

u Corrosive ash deposits will cause turbocharger rotor imbalanceand vibration, leading to bearing wear and possible failure

Vanadium


158/299

ash has potentially damaging effects within

the engine, especially in combination with sodium.

u Va na d i u m ( a nd so d i u m) o x i d i z e d u r i ng c o mb u st i o n a nd

f o r m l o w me l t i ng p o i nt sa l t s, wh i c h a d h e r e t o e x h a u st

v a l v e s, c a u si ng c o r r o si o n t o t h e v a l v e s a nd se a t s.

u T h e melting-point temperature of vanadium is 1970 oC,

but drops to its eutectic (lowest melting) point of 525 oC

when the vanadium-to-sodium ratio is 3:1.

u Sp e c i a l c o r r o si o n r e si st a nt a l l o y s (nimonic steel) are

used, along with continuous rotating valves to dislodgeash build-up and avoid repeated contact between the

same areas of the exhaust valve and seat.

Vanadium-Sodium Ratio


159/299

§ Vanadium alone in fuel does not usually cause problems.

§ Sodium levels in fuels leaving refineries are 50 ppm or less.

§ 1% sea water contamination adds 100 ppm sodium.

§ Vanadium/Sodium together form ashes during combustion.

Ø Highly corrosive, dissolve protective oxide layer.Ø Corrosion is accelerated by sulphur in the fuel.Ø Occurs at low melting points (near 525oC) and “sticky”.

§ Exhaust valve deposits result in grooving of seating area.Ø Loss of power Ø High exhaust temperaturesØ Fouling of the turbochargers and exhaust gas boiler

900

Vanadium-Sodium Ratio


160/299

900

800

700

600

500

10 20 30 40 50 60 70 80 90 1000

0102030405060708090100

Na2O %

V2O5 %

Vanadium-Sodium% ratios relate tomolecular weights

A s h M e l t i n g T e m p e r a t u r e

O C

Vanadium PentoxideV2O5

Sodium Vanyl VanadateNa2O.V2O4.5V2O5

Critical RatioVanadium/Sodium

Penta Sodium Vanadate5Na2O.V2O4.11V2O5

•

•

Sodium Meta Vanadate

Na2O.V2O5

Sodium Ortho Vanadate3Na2O.V2O5

EutecticPoints

Exhaust Valve Corrosion


161/299

u Grooved valve seating area caused by ash and sulphur corrosion

u Results in high exhaust temperatures, deposits and loss of power

Sulphur


162/299

Sulphur occurs naturally in crude oils, and is the principal

non-hydrocarbon component of heavy fuel oil.

u M o d e r a t e a mo u nt s o f su l p h u r c r e a t e su l p h i d e l a y e r s t h a t

e a si l y sh e a r , p r o v i d i ng d r y l u b r i c i t y t o f u e l i nj e c t o r s.

u Va na d i u m- So d i u m c o mp o u nd s f o r me d d u r i ng c o mb u st i o n

wi l l c a t a l y z e ( a i d ) t h e c o nv e r si o n o fsulphur dioxide (SO2 )

to form sulphur trioxide (SO3 ).

u Wi t h t h e a d d i t i o n o f wa t e r ,sulphuric acid (H 2 SO4 ) will be

formed. (turbocharger casing corrosion)

u Su l p h u r c a n r e d u c e t h e c y l i nd e r l u b e o i lBase Number

(mg KOH/g), destroying lubrication effectiveness.

Sulphur Trioxide-Dew Point Relationship


163/299

§ During combustion sulphur is oxidized to sulphur dioxide (S + O2 SO2).§ Sulphur dioxide, in the presence of oxygen (excess air) and catalyzed by vanadium

pentoxide (V2O5) is further oxid ized to sulphur trioxide (SO2 +1/2O2 SO3).

§ Sulphur Trioxide, in the presence of water, condenses to form sulphuric acid(SO3 + H2O H2SO4).

Dew Point OC

SO3 ppm

Dew Point as a function of SO3

150

100

10 706020 30 40 50

50.

Corrosion occurs in theexhaust system (stack)when the temperaturefalls below the dew point

SECA Area


164/299


165/299

Catalyst Fines Content


166/299

Referred to as “Cat Fines”, these are small particles ofaluminum-silicon used in Fluid Catalytic Cracking (FCC)process.

u T h e f l u i d z e o l i t e c a t a l y st ( a l u mi nu m- si l i c o n) i s e x p e nsi v e

a n d r e c i r c u l a t e d t o t h e r e f i ne r y r e g e ne r a t o r f o r r e - u se .

Bu i l d - u p i n t h e F CC f r a c t i o na t o r r e su l t s i n c a r r y - o v e r a nd

f u e l c o nt a mi na t i o n.

u T h e c o st t o r e mo v e t h e m f r o m a l o w- v a l u e “ r e f i ne r y wa st e ”

p r o d u c t i s t o o e x p e nsi v e .

u Ca t a l y st f i ne s a r e v e r y a b r a si v e a n d c a u se a c c e l e r a t e d

we a r t o f u e l p u mp s, i nj e c t o r s a nd e ng i ne s.

Ignition Quality of Marine Fuel


167/299

u Marine Fuels are a mixture of heavy residual oil and cracked

distillates, which can lead to poor ignition quality when blended

u Shell Research and British Petroleum have developed a simple-to-use indicator of ignition quality, the Calculated Carbon AromaticityIndex (CCAI) for HFO and the Cetane Index Indicated (CII) forMDO/MGO

u CCAI and CII are unit-less numbers allowing ranking the ignitionqualities.

u CCAI - the lower the number, the better the ignition characteristics.

u CII - the higher the number, the better the ignition characteristics.

u Ignition characteristics improve with increasing viscosity anddecreasing density.

CCAI-CII

Fuel (in)Stability & (in)Compatibili ty


168/299

« Instability: A single fuel with a low initial total sediment , degrades

over time to a signif icantly higher sediment level.

« Incompatibility: Two fuels, each with low total sediment , when mixedresult in a blended fuel with significantly higher sediment.

« General Rules to Avoid ProblemsØ Segregate new and old bunkers if possible.

Ø Do not mix paraffinic (MDO) and visbroken (HFO) fuels.

Ø Try to match density and viscosity of fuels.

Ø Test fuel and compare results to previous analysis before mixing.

HFO quality


169/299

500cSt@50ºC HFO quality


170/299

DREW Fuel and Lube Test Cabinet


171/299


172/299

Ø Mechanical TreatmentØ Chemical Treatment

Diesel Engine Fuel System


173/299

MainEngine

Ç

Supplypump

Heavy fuel oil

settling tank

Purifiers

Waste oilstorage tank

Dieseloil

tank

Waste oilpump

To aux. boileror incinerator

HFO recirculation

Fuel oil

sludge

Vent tank

From MDOStorage TanCirculatingpump

Filter 50microns


174/299

Waste Oil

è

è

in

out

Share asphaltene to


175/299

Benefits of Homogenizer

u Sludge Reduction (Installed in HFO Purifying System)


176/299

u Sludge Reduction (Installed in HFO Purifying System)Ø Complied with IOPP for sludge reduction

Ø Increase usable fuel 0.5 – 0.75%, cost saving

Ø Keeping purifiers in peak performance with lesser deposit.

Ø Reduce maintenance of purifiers.

Ø Reduce waste oil quantity.

Ø Reduce Incinerator operation hour 50%.

u Improving combustion (Installed in HFO Service system)Ø Shearing asphaltene to


177/299

Fuel Treatment – Chemical


178/299

Type of fuel treatment

« Additives for Tank Storage and Handling System

§Sludge Dispersant and Fuel Stabilizer

§Microbiocide for Bacteria Control

« Fuel Additives for Combustion and Deposits

§Combustion Catalyst (improver)

§Ash Deposit and Slag Modifier

« Soot Treatment

« Low Sulfur Fuel Treatment

C t ff ti l t i t t t f l f

AMERSTAT® 25


179/299

Cost-effective solut ion to protect your fuel from

microbial growth

• Seeks oi l and water interface to targetmicrobial growth

• Maintains fuel stabil i ty toprevent fuel degradationand microbial wastesludge formation

AMERSTAT® 25


180/299

• Protects from all types of microbialgrowth for all marine fuel oil grades

• Unparalleled dosagetreatment ratesInitial: 1 to 12500Maintenance: 1 to 25000

§ Kills sulfate reducing bacteria (SRB)to prevent H2S production

• Minimizes metal corrosionas a result of microbial growth

• Maintains cleaner fuel storage tanksand fuel filters


181/299

AMERGY-222


182/299

Before After

Dose to Fuel Storage before bunkering

Dosage: 1/6,000 - - 1/15,000

Emissions Profile


183/299

Air O2 = 21%N2 = 79%

FuelS = 2.7 %HC = 97.3 %

Lube

S = 0.05%Ca = 2.5%HC = 97%

Exhaust~76% N2~12.5% O2 !!!~6.5% CO2~5% H2O900~1300 mg/kg NOx

400~500 ppm SOx500~1500 ppm CO~200 ppm HC~120 mg/Nm2 PM

41.7% Heat Energy

49.3% Work

Combustion Catalyst

Problem:


184/299

Problem:

§ Complex hydrocarbon structures, high carbon residue and asphaltene levels.

§ Reduced vaporization o f fuel creates ign ition delay and incomplete combustion.

§ Loss of energy, smoke, soot and coke deposits

Solution:§ Blend of solvents, dispersing agents and “ noble metal” catalysts.

§ Catalysts oxid ize, drawing oxygen into the “ fuel-rich” combustion zone

to mix with hydrocarbons.Manganese, cerium, iron, zirconium, barium

and calcium are common combustion catalysts.

§ Drew Product: AMERGIZE, AMERGY-1000

Deposit and Slag Modifier

Problem:


185/299

Problem:§

Greater concentration of ash components in today’s fuels.§ Vanadium and sodium wi ll form corrosive ash deposits, which will adhere

to hot metal surfaces .

§ Vanadium Pentox ide deposits will convert SO2 to SO3, increasing the

potential for cold temperature corrosion.

Solution:

§ Blend of solvents, dispersing agents and “ noble metal” deposit modifier

catalysts.

§

Create different ash compounds from combustion with h igher melting pointsthan metal surface temperatures..

§ AMERGIZE is most cost -effective deposi t mod if ier.

Generator Engine’s Fuel Combustion

« Main engine about 100 RPM:§ 100 combustion /m = 0 6 second/combustion = 1 66 Combustions/S


186/299

§ 100 combustion /m = 0.6 second/combustion = 1.66 Combustions/S.

« Generator Engine about 720 or 900RPM:§ 360 combustion/m = 0.16 S/combustion = 6 combustion/S.§ 450 combustion/m = 0.13 S/combustion = 7.5 combustion/S.

« M/E and G/E are using same fuel.§ Carbon Residue about 14-16%, longer time required to mix with air to have

complete combustion.§ Asphal tene about 6-10%, easy to clustering and compat ib il it y problem.Longer time required for combustion .

« Generator engine has higher RPM than ME, T/C will have more deposit andshorter component life time by incomplete combustion.

« G/E’s fuel consumption is much lower than M/E. Recommend to use fueladditive to improve combustion.

AMERGIZE Shop Test Record

AMERGIZE, dosage: 1/200025% t t 262 5 F l 172 / /h (13% i )

No Fuel Treatment

25% output: 262 5 ps Fuel cons: 198 g/ps/hr


187/299

25% output : 262.5 ps, Fuel: 172g/ps/hr (13% saving)

50% output : 525.0 ps, Fuel: 157 g/ps/hr (5.42% saving)

75% output: 787.5 ps, Fuel: 158 g/ps/hr (2.5% saving)

85% output 892.5 ps, Fuel: 160 g/ps/hr (1.2% saving)

100% output 1050 ps, Fuel: 163 g/ps/hr (0% saving)

25% output: 262.5 ps, Fuel cons: 198 g/ps/hr

50% output 525,0 ps, Fuel cons: 166 g/ps/hr

75% output 787.5 ps, Fuel cons: 162 g/ps/hr

85% output: 892.5 ps, Fuel cons: 162 g/ps/hr

100% output 1050 ps, Fuel cons: 163 g/ps/hr

AMERGIZE Sea Trail Data


188/299

AMERGIZE Performance in Generator Engine

NO FUEL TREATMENT AMERGIZE


189/299


190/299

Exhaust Gas Deposits Treatment

Restore Efficiency


191/299

Restore Efficiency

• Removes existing deposits

• Maintains heat recovery

transfer surfaces clean

• Eliminates stack f ires

• Minimizes acid corrosion E x h a u s t G a s B

o i l e r

O u t p u t %

Relationship of Exhaust

Gas Boi ler to Main Engine Load

LT-SOOT Release

Economizer exhaust-side powder treatment


192/299

p

§ low activation temperature (200ºC) catalyst

• bring oxygen into soot and convert to dry and loose

powder type deposit.

• maintains heat recovery transfer surfaces clean

§ effective at low engine loads

• minimizes likelihood of stack fires

• improves soot blower performance

• Followed by soot blowing, this is the most cost-effective method to treat exhaust gas economizer

LT Soot Release Dosing Unit

• Air driven dosing unit for


193/299

soot treatment to reduce

soot deposit in Economizer

and exhaust gas boiler

• Manual operation

DREWCLEAN EST – Economizer soot treatment

§ A special l iquid treatment that catalyzes soot to dry and non-adherent to


194/299

§ A special l iquid treatment that catalyzes soot to dry and non adherent to

heat transfer surface, maintains entire heat transfer area clean§ Improves soot b lower performance and reduce low temperature

corrosion.

§ Effective at low temperature down to 200°C

§ The product is normally dosed 1 liter per day whenengine is operating

§ The EGT dosing system can be adjusted to providethe exact dosing desired. It is recommended to injectDREWCLEAN EST every 8 hours, with an injection of12 to 15 minutes.

§ For optimum result, soot blow shou ld be operatedbetween 30-90 minutes after chemical inject ion

Low Sulphur Fuel Problems

L S l h f l (


195/299

u Low Sulphur fuel (


196/299

p y,

which may cause clogging of fuel filters and separators and stickingof fuel injection pumps asphaltene deposits on plunger and barrel)

Fuel sulphur content versus lubricant BN

1. Where the sulphur content in the fuel is above 1.5 %, the use of approved70BN cylinder oil is recommended.


197/299

70BN cylinder oil is recommended.

2. Where the sulphur content in the fuel is below 1.5 %, approved 40BN cylinderoil is recommended.

3. Using LFO or LSHFO with 70BN cylinder lubricant should be avoided,because the excessive calcium ash in BN is likely to deposit on the pistoncrown land. These deposits may become very hard and contact between thedeposits and the cylinder liner wall can cause bore polishing and lead to

wear 4. The sulphur in the fuel oil has a lubricating effect .

5. The use of DO and GO with a sulphur content close to zero and, might causefuel pump and fuel valve wear and, consequently, the risk of sticking.

6. Generator engine lube oil system may not changed whi le fuel changed,

above problems may have higher risk than Main engine

Changeover between HFO & MGO Fuels

Changeover between High and Low-Viscosity Fuels


198/299

§ T o p r o t e c t t h e i nj e c t i o n e q u i p me nt a g a i nst r a p ima y c a u se st i c k i ng / sc u f f i ng o f t h e f u e l v a l v ea nd su c t i o n v a l v e s, t h e c h a ng e o v e r i s t o b e c ama k e r ’ s c h a ng e o v e r p r o c e d u r e.

§ According to the inst ruct ion manual, the temperature should not be changed bymore than max. 2ºC/min.

§ For example, diesel oil is to be changed to HFO:1. The system contains 40ºC diesel oil2. The diesel oil is heated to 80ºC before adding the HFO. This takes (80 �

Chemical Boiler Water Treatment

Documents

Transcript of Chemical Boiler Water Treatment