Indirect Fired Heater Training Module

le Training Modu odule

Describe and Operate Indirect-Fired ter rs Lin Li ne Heate

Human Development Consultants Ltd.

Cover Photo ou r te sy of P r e ss on E N E LEX and Pet r o -C anada sy of ss on C ou r te r e NE RF RF LEX r o -C anada

D escri escri b be a nd nd O O p p era era t te I nd nd irec irec t-F t-F ire ire d L d Li n ne H ea ea t ters e rs

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ISBN 1-55338-040 -1 Canadian Cataloguing in P ublica tion Data

1. Pi Pipeli peline nes—Equi Equipment and supp upplilie es. I. HDC Human Developm opment Consultants. TP757.F P757.F48 2005 665.7 665.7’’44 C2005 2005--906879906879-5 This trai ning ki t c onsis ts of the following parts: Tra Tr aining Modu odulle and Sel Self-C -Che heck Perrfo Pe form rman ance Check Knowl Kno wledge edge Check and An swer Key Exercise Job Ai Blank Answer Sheet Aid

Publi Published by HDC Human Developm opment Consultants Ltd. Publi Published in Canada

HDC Human Development Consultants Ltd. Website: E-m -ma ailil:: Phone:

www.hdc.ca [email protected] (780 ) 463 -3909

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Con tents Training Objectives

1

1

Introduction

1

2

Heat Medium Components

7

2.1 2.2

7 8

3

4

Heate eaterr Shell Shell Pr Produced Gas Flo Flow Coil

Combustion Components

3.1 3.2 3.3 3.4 3.5

Fue uell Gas Suppl Supply Fue uell Gas Cond ondiition oniing System tem Bur Burne nerr Fue uell Gas Bur Burne nerr Assembly Fire Fire Tube Assembly

Combustion Safety Controls

4.1 4.2 4.3

Hazardous / Upset Cond ondiitions that Shut Down the Line Heate eaterr Pneum Pneumati atic Combustion Safety Cont ontrrols Microp oprrocessor-Ba r-Based Combustion Safety Cont ontrrols

12 12 16 17 21 27 28 29 29 32

5

Site Layouts 5.1 Gas Wellsites 5.2 Gatheri Gathering ng System tem Si Sites

37 37 39

6

Choke O peration

40

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Con tents (con tinu ed) 7

8

Site Systems and Equipment 7.1 Cold-Climate -Climate Enclosure Buil Build ding 7.2 Che hemi mical In je jection System tems 7.3 Downho nholle Heat Stri String ng 7.4 Flo Flow Measurement 7.5 Combustible Gas, Toxic Gas, and Fire Fire Detection 7.6 SC SCADA (Super Supervisory Cont ontrrol and Data Acqu quiisition on)) System tem 7.7 El Electrical Pow Power System tem 7.8 Em Emergency Shutdow Shutdown (ESD) ESD) Pu Pushbuttons

41 41 44 44 46 48

Line Heater Safety

52

8.1 8.2 8.3 8.4

52 53 57 58

Safety While ile Tra Traveling ling to the Li L ine Heate eaterr Si Site Safety at the L Liine Heate eaterr Si Site Safety at the L Liine Heate eaterr Buil Build ding Safety When Leaving the Li Line Heate eaterr Si Site

49 51 52

Operating Variables

58

Prepare Line Heater for Startup

59

10.1 Investigate Li Line Heate eaterr Shutdow Shutdown 10.2 Restar tart Li Line Heate eaterr

59 61

11

Light Line Heater Burner Manually

61

12

Self Check

66

13

Answer Key

77

9 10

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Training Objectives

1

Upon completi etion of thi this tr training kit, you will be will be abl able to: Describe ribe the pur purpose and impo imporrtance of ind ndir ire ect-fired ired line line heaterrs heate Describe ribe line line heate heaterr: components and their their fun function combustion safety cont ontrrols Describe ribe line line heate heaterr site layouts Describe ribe line line heate heaterr site system tems and equi equipment Describe ribe line line heate heaterr safety Describe ribe manua anuall light lightiing of line line heate heaterr bu burrne nerr Describe ribe line line heate heaterr ope operrati ating variab riablles and oper operati ations mon oniitori toring ng Troub Troublleshoot line line heater heaters

odu uction Introd Indire Indir ect-fired ired line line heate heaterrs ar are used to heat natur natu ral gas befo beforre ributiion the gas is shipped by pi pipe peliline ne fo forr pr processing or or fo forr di distribut to resident dentiial and industria rial custom tomers. During ring shipp ppiing, p prrocessing, and di distribut ributiion, the natur natural gas coo oolls as: heat is lost to coo ooller surround rroundiings (e.g., a subsurface gas pipe peliline ne loses heat to the surround rroundiing soil) the p prressure of the gas is reduced Gas coo ooliling ng can cause pr prob obllems do dow wnstrea eam m on the pi pipe peliline: ne: the fo form rmat atiion of hydrates which can bl block the p piipe peliline ne (see the textbox on page 4 about hydrates and their their ha hazards) hydrates fo form rmed ed in mete eterrs can cause inaccurate read eadiings the chilling illing of dow downstrea eam m equ equiipment: in mechan haniical equ equiipment (e.g., mete eterrs, regu egullato atorrs, and ricated valves), cold tem tempe perratu aturres may pr prevent lub ubri inte nterrna nall components fr from ope operrati ating effectively in gas ana anallysis instrumentat entatiion, cold tem tempe perratu aturres may cont ontri ribute bute to inaccurate sampling ling results

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Liine Heate eaterr Locat atiions in Natu aturral Gas P Prrocessing/ Di Distri ribut butiion Figure 1 —Typical L

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Indire Indir ect-fired ired line line heate heaterrs heat the natur natural gas to pr prevent hazardous hydrate bl blockages and ffrrozen do dow wnstrea eam m equiipment. equ Line heater heaters ar are typically install talled: ed: at gas wellsites whe herre the h hiigh wellhead llhead p prressure must be reduced so that gas can fl flow via lower pr pressure pi piping to a dow do wnstrea eam m gas pl plant. A ma jo jor dr drop in gas pr pressure causes gniificant coo ooliling ng of the gas to the poi point whe herre hydrates sign cou oulld form form.. Li Line heater heaters ar are install talled ed at the site to heat the gas to pr prevent hydrate form format atiion. link remote gas along gas gatheri gathering ng system tem pi pipe peliline nes that lin fields to gas pr processing pl plants. Gas coo oolls as it passes thr through the pi pipe peliline ne and loses heat to the surround rroundiing subsoil. il. Li Line heater heaters al along gas gatheri gathering ng system tem pi pipe peliline nes reheat the gas to pr prevent hydrates fr from fo formi rming. ng. at city gate stat tatiions whe herre local di distribut ributiion compan paniies purrchase, mete pu eterr, regu egullate, and odori odorize the pr processed naturral gas received fr natu from tr transmission pi pipe peliline nes. The city gate stat tatiion on’’s pr pressure regu egullato atorrs reduce the gas pr pressure from its hi high tr transmission line line pr pressure to the lower local distribut ributiion line line pr pressure. Li Line heate heaterrs at city gate stat tatiions provide enough heat to pr prevent chilling illing of dow downstrea eam m equiipment. equ This modu ire ired line line odulle focuses on the oper operati ation of ind ndir ect-fired heaterrs at gas wellsites and a heate allong gas gatheri gathering ng system tem pipe peliline nes. Indir ire ectFigure 2 — Ind Fired Fir ed Li Line Heate eaterr at Wellsite sy of ss on (C ou ou r te sy of P r e ss on r te r e E N E LEX and Pet r o NE RF RF LEX ro - - anada ) C anada

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Hydrates and Their Hazards

Hydrates a arre a mixtu turre of wate aterr and gas that form forms crysta talls unde underr certa taiin tem tempe perratu aturre and pr pressure cond ondiitions. In a h ydrate, gas molecules (such as methane, ethane, propane, butane, hydrogen sulph phiide, and carbon di dioxide de)) a arre em embedded inside a latt attiice of wate aterr molecules. Hydrate crysta talls deposit on solilid d surfaces and restrict gas flow. Hydrates can pl plug valves, mete eterrs, instruments, and fl flow liline nes. Hydrates: - can form form at at hi high pr pressure, even when the tem tempe perratu aturre of the fl f lowi wing ng gas is above the fr freezing poi point of wate aterr - can form form when fr free wate aterr condenses in the gas strea eam m - tend to fo form rm at at sha harrp bends in fl flow liline nes and at locat atiions whe herre the pr pressure dr drops. However, hydrates can occur anywhe herre the tem tempe perratu aturre dr drops be bellow the hydrate rmat form fo atiion poi point.

HYDRATE "TRIANGLE"

F R

E E R E U W S A S T E R HYDRATE E R P

TEMPERATURE

Hydrate form format atiion can be pr prevented by: - ope operrat atiing at hi high gas te tem mpe perratu aturres - ope operrat atiing at low gas p prressures - ope operrat atiing at a lower wate aterr content - in j je ecting a hydrate inh nhiibito torr, such as methano ethanoll Prevent entiing hydrates f frrom fo formi rming ng is im impo porrtant: - Cl Clea eari ring ng hydrate bl blockages is a hi high gh-ri -risk activity. Incorr rre ect hydrate removal can cause pi pipe peliline/equ ne/equiipment ruptu upturre and put peopl people in harm’ harm’s way. - Hydrate bl blockages inte nterr rrupt upt business: a hydrate bl blockage means that gas is unab unablle to fl flow.

Ind irect-F ired

Line Heater ––Operating Principle c In an i nd nd ir ir e ec t t - fired ired line line heater heater, a fir fire e tube imme immersed in a heat med ediium (HM), (HM), such as gl glycol, heats the HM (Figu (Figurre 3) 3). The naturral gas passes th natu thrrough a fl flow coil that il that is al also imme immersed in the HM bath HM bath and is heated ind ndir ire ectly.

NOTE

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ec t t -fired ired line line heater ire immersed in the c In a d ir ir e heater, the ffir e tube is imme product bei being heated.

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NOTE

In th thiis modu odulle, the term terms li ne ne heate r r and and heate r r r refe eferr on onlly to ind ndir ire ect-fired ired line line heater heaters.

––Liine Heate eaterr Ope Operrat atiing Pri Prin nciple Figure 3 ––L

The fir HM bath as fo fire e tube heats the HM bath follllo ows: A fir fire e tube is sub ubm merged in the lower pa parrt of the HM bath. HM bath. A flame tr travels do dow wn the ffir ire e tube and tr transfer fers heat to the HM. HM. Coo oolled combustion gases fl flow fr from the fir fire e tube and rise up a stack. As the HM’s te tem mpe perratu aturre increases, its density decreases to create therm therma al circulati ation in the bath: Hot, less dense HM rises to the upper uppe r pa parrt of the she hellll.. The gas fl flowing wing in the gas fl flow coil ab il absorbs heat ffrrom the HM. HM. The HM’s te tem mpe perratu aturre decreases and its density increases. The coo oolled HM sinks to the bottom botto m of the hellll to to be reheated. she

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Line Heater Application and Site Requirem ents A line line heater heater must be appr approp opri riate ate fo forr site cond ondiitions: it must be ablle to heat the gas enough to pr ab prevent hydrate form format atiion. -mounted and can be tr Line heater heaters ar are usua ualllly skid-mounted transferr ferred ed ween sites. Befo line heater betw bet Beforre a line heater is tr transferr ferred ed to a new new site, will ensure that: you ourr company will en the heater’ heater’s design specificati ations match cond ondiitions at the new ne w site the heater heater and its components comply with with regu egullato atorry requ equir ire ements fo forr the ne new w site This modu odulle describe ribes line line heater heaters that a arre corre rrectly designed for for site cond ondiitions and meet regu egullato atorry requ equir ire ements. Indirect-Fired

Line Heater ––Operator’s Role

Carefu efull mon oniitori toring ng and cont ontrrol of ind ndir ire ect-fired ired line line heate heaterrs cont ontri ribute bute to the safe and effi efficient oper operati ation of the heater heate r and prevents hydrate form format atiion in dow downstrea eam m pi piping. Oper Operati ations include: mon oniitori toring ng oper operati ating variab riablles (tem tempe perratu aturre, pr pressure, bath level, fl flow) to w) to assess /opt /optimi imize heater heater ope operrati ation star tarting up and shutt huttiing dow down the heater heater troub oublleshoot hootiing heater heater pr prob obllems and rectifying mino minorr prob obllems jor pr promptl ptly repo eporrting ma jo prob obllems Addi Additiona onall Oper Operato atorr responsibilit ilities ar are described ribed in Section 10.

Module Contents For ind ndir ire ect-fired ired line line heate heaterrs, thi this modu odulle describe ribes: heat med ediium components combustion components combustion safety cont ontrrols site layouts site system tems and equi equipment safety line line heater heater bu burrne nerr light lightiing operrati ope ating variab riablles and oper operati ations mon oniitori toring ng troub oublleshoot hootiing

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2

Heat Medium Com pon ents This section describe ribes the ind ndir ire ect-fired ired line line heate heater’ r’s she hellll and and produced gas fl flow coil. il.

NOTE

In th thiis modu odulle: rm p r odu c e wing ced d ga s s refe the te term r odu eferrs to the natur natural gas fl flowing thr through the coil and il and be beiing heated s refe the te term rm fue l l ga ga s eferrs to the gas that fuel fuels the bu burrne nerr s s refe the te term rm i n ns t t r r u um m entat e ntat i i on on ga s eferrs to the natur natural gas or or propane used to oper operate pneum pneumati atic cont ontrrols

2.1 Heater Shell The heate heaterr she hellll is a hori horizonta ontall, cylind lindri rical vessel that oper operates at atm atmosphe pheri ric pr pressure. The she hellll ho hollds the large volume of HM that HM that ttrransfer fers heat ffrrom the fir fire e tube to the pr produced gas flow coil. il. The heater heater she hellll ha has tw two end fl flanges: the p prroduced gas fl flow coil is install talled ed th thrrough one end flange the ffir ire e tube is install talled ed th thrrough the other other end ffllange

WARNING

For colde derr climate limates, the she hellll may be insulated. On ol olde derr line line heaterrs, asbestos may have been used fo heate forr insulati ation. Follo llow you ourr company pr procedu edurres fo forr hand handliling ng asbestos.

Expansion Tank The heate heaterr she hellll ha has a top expansion tank (also called lled a s u ur r ge ge tan k e s e o k or se r vo ir or r e r v i r ). The tank has suff uffiicient volume: with HM to ensure that the heater heate r she hellll is complete etelly fill filled ed with (i.e., (i.e., the liqu liquiid full fully covers the p prroduced gas fl flow coil) to accomm mmodate odate HM e HM expansion when the HM te HM tem mpe perratu aturre increases du duri ring ng cold star tartup The expansion tank has a top hatch (thi thief hatch) that serves as both an HM f HM fill ill po porrt and a vent/b ent/brreathe eatherr. Because the she hellll can onlly with on withstand atm atmosphe pheri ric pr pressure, the hatch’s vent/b ent/brreathe eatherr provides both overpressure and vacuu uum m pr protection: Venti Venting pr prevents she hellll ruptu upturre: During ring line line heater heater star tartup, the HM is heated to oper operati ating tem tempe perratu aturre and expands. Air Air is pushed out the hatch. Augu s st t , 2014

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In case the ffllow coil ruptu upturres, vent entiing pr protects the she hellll from overpressure ruptu upturre. Breath eathiing pr prevents she hellll vacuu uum m collap llapse. After After the line line heaterr is shut dow heate down, the HM coo oolls and cont ontrracts. Air Air is drawn in thr through the hatch to compensate fo forr the decrease in HM volume.

NOTE

For line line heater heaters that have w ate ate r r bath baths, the expansion tank min minimizes wate aterr vapo aporr loss. This type of expansion tank is kno v now wn as a w ate ate r r s a av e er r . The lower te tem mpe perratu aturre at the top of the expansion tank condenses the stea team m rising off the liqu liquiid surface.

Heating Medium The HM is ei eithe therr wate aterr or or a gl glycol-wate l-waterr soluti ution. A gl glycolwate aterr mixtur ture has a lower fr freezing poi point and a hi highe gherr bo boili iling ng poiint than wate po aterr. The type of HM u HM used depends on the climate limate ired and requ equir ed heati heating: limates whe HM does not have Water is used in hot climate herre the HM doe to be p prrotected ffrrom fr freezing. When using a wate aterr bath, a line line heate heaterr is ope operrated be bellow wate ater’ r’s bo boili iling ng po poiint to p prrotect agaiinst boili aga boiling ng off the bath wate aterr. Distilled water may be used in colde derr climate limates. Compa parred to wate aterr with with impu impuri ritties, di distilled illed wate aterr fr freezes at a lower tem tempe perratu aturre. utions ar are used: Glycol-water bath soluti in cold climate limates whe herre the bath must not ffrreeze (in (in case the line line heate heaterr shuts do dow wn duri during ng cold weathe eatherr operrati ope ations) in any climate limate whe herre a hi high bath tem tempe perratu aturre is requ equir ired ed The wate aterr and g gllycol-wate l-waterr soluti utions used in line line heater heaters ar are with corro rrosion inh treated with nhiibitor tors to pr prevent inte nterrna nall fou fouliling ng and rrosion. Your corro Your company may stipu pullate that: l-waterr mixtur a specific gl glycol-wate ture be used instead of veh ehiicle antiifreeze ant HM be HM be sampled regu egullarly to verif rify gl glyco / l/ wate aterr concent entrrati ation, ffrreezing/bo ng/boili iling ng po poiints, and corro rrosion inh nhiibitor tor strength

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The level of the heat med ediium is dete determi rmined ned by tw two factor tors: The fir fire e tube and gas fl flow coils must be covered Som So me em empty space is requ equir ired ed for for the therm rma al expansion Follo llow the manufactur turer’s recomm mmendat endatiions fo forr the requ equir ired ed level of the heat med ediium.

2.2 Produ ced Gas Flow Coil The pr produced gas fl flow coil (also called lled the tube bundl bundle) is a removab ablle length of pi piping install talled ed above the fir fire e tube in the HM bath. HM bath. Pr Pressurized pr produced gas fr from the wellhead llhead or or pipe peliline ne is dir dire ected th thrrough the fl flow coil fo il forr heat heatiing. The gas fl flow coil must alw alwa ays be complete etelly sub ubm merged in the HM du HM duri ring ng line line heater heater ope operrati ation. Keepi Keeping the coil sub ubm merged ensures that the pr p roduced gas in the coil is effectively heated. The coil must remain sub ubm merged even after after the line line heater heater is merged ensures that shut off and has coo oolled. Remaining sub ubm rrosive effects of the air the coil is not exposed to the corro a ir (drawn in thr through the vent/b ent/brreathe eatherr du duri ring ng coo ooll do dow wn). Engi Enginee neeri ring ng and/o and/orr regu egullato atorry codes di dictate ho how w the p prroduced gas fl flow coil is manufactur tured, p prressure-tested, and re-tested/ inspected duri during ng the coil’s service life life to ensure the coil can with withstand the hi high gas pr pressures. The conf onfiigu gurrati ation of the coil depend il depends on both: the num numbe berr of heat heatiing stages needed by the p prroduced gas heatiing appli heat applicati ation (eithe therr one o orr tw two stages) the num numbe berr of coils needed to handl handle the pr produced gas fl flow rate (eithe therr one coil fo il forr low fl flow rates or or multiple par paralle llel forr hi highe gherr gas fl flow rates) coils fo

Heating Stages line heater heaters which must pr provide One heating stage is used on line onlly a mode on oderrate te tem mpe perratu aturre increase (such as those on gatheri gathe ring ng system tem pi pipe peliline nes). Figu Figurre 4 on the foll wing page sho w a one heati line follo owing how heating stage line heaterr. heate

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One--Stage Figure 4 —One Produced Gas Fl Flo ow Coil

Two heating stages ar are used on line line heate heaterrs which must provide a g grreat a am mount of heati heating to counte ounterr the intense coo ooliling ng caused by a large pr pressure reduction. (La Larrge pr pressure reductions comm mmon onlly occur at sites whe herre the wellhead llhead gas pressure must be reduced to match lower gatheri gathering ng system tem pressure.) e.) On tw two-stage line line heater heaters (see Figu Figurres 5 and 6 6)), the coil p il prrovides a pr preheat eheatiing stage befo r re e the the p prressure reduction and a reheat eheatiing stage afte r r the the p prressure reduction. (Preheat eheatiing the gas befo beforre a large pr pressure reduction ensures that the coo ooliling ng caused by the p prressure dr drop does not chill the ill the gas to bellow hydrate be ate--form format atiion tem tempe perratu aturre.) e.)

The pr produced gas fl flows th thrrough the tw two-stage heater heater as foll follo ows: the p prroduced gas fl flow ente enterrs the p prreheat coil and il and is heated the heated pr produced gas fl flow leaves the p prreheat coil and il and passes th thrrough the pr pressure reduction valve (choke) afterr pr afte pressure reduction (and resulting coo ooliling ng)), the produced gas fl flows into the line line heate heater’ r’s reheat coil, il, is heated to the fi fina nall te tem mpe perratu aturre, and then e xits the line line heaterr. (The heate (The reheat coil is al also kno now wn as the post-heat coil. il.) For line line heate heaterrs equ equiipped with with pr preheat and reheat coils: The pr preheat coil is bu buililtt to with withstand hi highe gherr pr pressure than the reheat coil. il. The conf onfiigu gurrati ation of the pr pressure reduction valve (choke) ween the pr betw bet preheat and reheat coils can vary:

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The valve may be a manua anuall valve whose body is imme immersed in the HM bath. HM bath. The valve may be an exter terna nall cont ontrrol valve that is autom auto mati atically positioned as pa parrt of a wellhead llhead pr pressure cont ontrrol or or fl flow cont ontrrol strategy to mainta ntaiin fl flow and/or and/or pressure setpo etpoiint (as described ribed in Section 6) 6).

NOTE

For a deta detaililed ed descript riptiion of p prrocess cont ontrrol and cont ontrrol loop strateg ategiies, refe eferr to these HDC t HDC trraining kits: s si i c c In st s D e esc c ri ri be be Ba s In s t r r u um m entat e ntat i i on on and C ont ont r ro o l l St St r rateg a teg i i e es s ce ss s s and ce ss ss C ont D e esc c ri ri be be P r r o o c e s C ont ont r ro o l M l M ode ode s and P r ro o c e ont r r o ol l c no l l og y T e ec hno h og y

Two o-Stage Figure 5 —Tw Produced Gas Fl Flo ow Coil

Refe eferr to the next page for for a pi pictur ture of a ttw wo stage gas coil and il and choke.

Number of Produ ced Gas Coils Dependi epending on the gas fl flow to be heated, a line line heater’ heater’s produced gas coil may consist of a sing nglle coil o il orr multiple, parralle pa llel coils: single coil. A sing nglle coil may be suff uffiicient to heat a small gas fl flow. A sing nglle coil is conf onfiigu gurred as a spira iral-wound l-wound bundlle or bund or as a tube tube--type bundl bundle (whe (wherre the coil makes num nu merous passes back and fo forrth befo beforre leaving the line line heater) heate r)..

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eaterr wi with th Tw Two o-Stage Pr Produced Gas Coilil and and Choke Figure 6 —Line Heate sy of s en c o M fg. ou r te sy of La r en & D’ Ami c fg. Ltd. ) Ltd. ) (C ou r te r s

flow, the fl f low multiple, parallel coils. To heat a large gas fl to the line line heater heater br branches outside of the heater heate r to feed multiple, pa parralle llel, tube tube--type coils. After After passing th thrrough the heaterr, the ffllows recombine. heate

3

pon nents Com bustion Com po The bu merged fir burrne nerr dir dire ects a flflame into the sub ubm fire e tube to heat the HM. HM. The fo follllo owing wing components suppo upporrt the heater’ heater’s combustion oper operati ation (see Figu Figurre 7) 7): fuell gas supp fue upplly fuell gas cond fue ondiition oniing system tem burrne bu nerr fue fuell gas tr train burrne bu nerr assembly fire ire tube assembly flame arr arre estor tor / / wind wind box

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3.1 Fuel Gas Supp ly A line line heater heater needs a reliab liablle sou ourrce of fuel fuel gas. The fue fuell gas sou ourrce may be: a dr drawoff fr from the line line heater heater pr produced gas out outllet a natu naturral gas ut utili ilitty di distribut ributiion netw network or or nea nearrby gas processing pl plant a pr propane stor torage system tem eater’ r’s Combustion Components Figure 7 —Line Heate

Drawoff from Line Heater Outlet The pr produced gas heated in the gas fl flow coil may be of suff uffiicient quali qualitty to suppo upporrt effi efficient combustion. In thi this case, a lipstrea m of heated pr withdrrawn dow m of slip eam produced gas is withd downstrea eam the line line heater heater. The pr produced gas may conta ontaiin toxic conta ontami minant nants at tr trace levels that do not impa impair ir reliab liablle combustion. However, some conta ontami minant nants ar are hazardous /toxic, even at ttrrace levels. Refe eferr to Section 8.3 fo forr safety pr precaut autiions at line line heater heater sites.

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In app applilicati ations whe herre pr produced gas is used as the fue fuell gas sou ourrce, the fuel fuel gas dr drawoff may be equ equiipped with: with: a manua anuall isolati ation bl block valve a pr pressure regu egullato atorr to reduce the gas pr pressure

WARNING

When pr produced gas is used as fue fuell gas, the fuel fuel gas typically does not conta ontaiin a leak detection odor odorant. A Allthough the fuel fuel gas may have a pet petrroleu eum m odo odorr, don’ don’t assume that you will be will be ablle to smell a ab ll a fuel fuel gas leak.

Natural Gas Utility or Nearby Gas Plant If the pr produced gas is not suitab tablle, fue fuell gas may have to be upplilied ed fr from offsite. Two Two sou ourrces ar are: supp mme l-qualilitty natu ilitty comm ercial-qua naturral gas pi piped fr from a gas ut utili ributiion netw distribut network sales-qua qualilitty natu naturral gas fr from a nea nearrby gas pl plant

NOTE

At some remote gas pl plants, a slip lipstrea eam m of sales gas is withd withdrrawn to supp upplly equ equiipment in the surround rroundiing gas fi fields. In app applilicati ations whe herre the fuel fuel gas arri arrives fr from offsite, the fue fuell gas pi piping may be equ equiipped with: with: a manua anuall isolati ation bl block valve an ESD ESD (emergency shutdo hutdow wn) valve to close auto autom mati atically in case of a site em emergency a pr pressure regu egullato atorr to reduce the gas pr pressure to an inte nterm rmed ediiate pr pressure a fl flowmete wmeterr to record fuel fuel gas consumpti ption

WARNING

Find Find out if the fuel fuel gas at you ourr site is odo odori rized: Fue uell gas arri arriving fr from an offsite locati ation may conta ontaiin a leak detection odor odorant. Fue uell gas fr from a gas ut utili ilitty is typically odo odori rized, whe herreas fuell gas fr fue from a gas pr processing pl plant may not be. Don on’’t assume that you will be will be ab ablle to smell a ll a fue fuell gas leak.

Propane Storage Sys tem If the pr produced gas is not suitab tablle for for use as fue fuell gas, anothe anotherr optiion is to use pr opt propane supp upplilied ed fr from a stor torage system tem. The propane stor torage system tem consists of an outdoor outdoor pr propane Augu s st t , 2014

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stor torage tank that hol holds a large volume of liqu liquiid pr propane under under pressure. The pr propane is withd withdrrawn fr from the tank using ei eithe therr: propane li qu qu i id d dr drawoff (for for large gerr capacity system tems) propane v apo apo r r dr drawoff (for for smalle ller capacity system tems)

Prop ane Liquid Drawoff Propane liqu liquiid fl flows or or is pu pum mped fr from the bottom bottom of the tank thr through the tank’s manua anuall liqu liquiid isolati ation valve. The pr propane liqu liquiid is then heated in a specialty heater heater kno now wn as a pr propane vapo apori rizer. Prop ane Vapor Drawoff Propane vapo aporr leaves the top of the tank th thrrough the tank’s manua anuall isolati ation valve and is dir dire ected thr through a regu egullato atorr to reduce the p prropane pr pressure. A pr propane tank conf onfiigu gurred to supp upplly pr propane vapo aporr may have ring diffi fficulty supp uppllying suff uffiicient vapo aporr du duri ng cold weathe eatherr. A propane tank’s ab abili ilitty to di discha harrge vapo aporr decline lines as the outdoor outdoor te tem mpe perratu aturre dr drops and the tank’s pr propane level dr drops. To pr prevent an inte nterr rrupt uptiion in pr propane vapo aporr fl flow, the p prropane tank may be winte winteri rized with with an exter terna nall fl flameless heater heater (a cata atallytic heater heater, described ribed in Section 7.1 7.1)). The heater heater pr provides rad adiiant heat to the tan k’s wall to ll to ensure suff uffiicient p prropane vapo aporr.

Propane System Monitoring The Oper Operato atorr checks the p prropane system tem to ensure cont ontiinued fuell gas supp fue upplly: mon oniitor tors pr propane stor torage tank pr pressure and requests a propane refill efill,, if necessary conf onfirm irms that the pr propane system’ tem’s valves ar are corre rrectly conf onfiigu gurred ring winterr, conf irms the oper duri du ng the winte onfirm operati ation of the pr p ropane tank’s heater heater and ffllow of pr propane vapo aporr fr from the tank

WARNING

At sites whe herre pr propane is used as fue fuell gas, you ourr pe perrsona onall combustible gas detector tor must be ab ablle to detect: propane fuel fuel gas leaks methane pr produced gas leaks Consult you ourr company’s hea heallth and safety pr practices.

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3.2 Fuel Gas Con ond ditioning System All fue ll fuell gas unde underrgoes cond ondiition oniing (see Figu Figurre 7) 7): fuell gas pr fue preheat eheatiing fuell gas scrubb fue ubbiing addiitiona add onall fue fuell gas fil filttrati ation

Fuel Gas Preheating The fuel fuel gas passes th thrrough a pr preheat coil imme immersed in the HM bath. After After heat heatiing, the fue fuell gas fl flow br branches and ffllows thr through pr pressure regu egullato atorrs in the main bur burne nerr and pil pilot ot bur burne nerr upplly line lines. Pr Preheat eheatiing the fuel fuel gas befo beforre it fl flows th thrrough the supp rming. pressure regu egullato atorrs pr prevents hydrates fr from fo formi ng.

Fuel Gas Scrubb ing Liqu quiids ent entrrained in the fuel fuel gas must be removed to p prrevent: poorr bu poo burrne nerr ope operrati ation; the liqu liquiids may not bu burrn consistent tentlly: the bur burning liqu liquiids may pr produce a smoky fl flue gas exhaust liquiids may not bu the liqu burrn and may poo pooll at the bottom botto m of irebo liquiid may dr the ffir ebox housing. This poo poolled liqu drain out of the ffir irebo ebox fl flame arr arre estor tor, creat eatiing a ffir ire e hazard. The poolled liqu poo liquiid may suddenl uddenly ign gniite or or explode. discha harrge of ffllamm mmab ablle dr drop opllets out the top of the fl f lue stack which may ign gniite surround rroundiing vegetati egetation liqu liquiid ent entrry into instrumentat entatiion line lines. Li Liqu quiids inte nterrfer fere with with the oper operati ation of pneum pneumati atic cont ontrrols and instrumentat entatiion. The fuel fuel gas scrubbe ubberr is a small sepa eparrato atorr whe herre liqu liquiids in the incoming ming fuel fuel gas sett ettlle to the bottom bottom and the gas rises to the top out outllet. In case of a h hiigh liqu liquiid level in the scrubbe ubberr, the scrubbe ubber’ r’s wn the protective cont ontrrols stop the fl flow of fue fuell gas, shutt huttiing do dow line line heate r’s hi heaterr bu burrne nerr. The scrubbe ubber’ high level pr protective cont ontrrols may consist of: an inte nterrna nall fl float ball ball that that rises with with the liqu liquiid until until the the ba ballll sea ealls off the scrubbe ubber’ r’s fue fuell gas out outllet a fl float level swit witch that is tri trigge ggerred at a pr preset liqu liquiid level to stop the fl flow of fue fuell gas by closing a shutoff valve.

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The scrubbe ubber’ r’s dr drain valve depends on the liqu liquiid content of the fuell gas: fue At sites whe herre the fuel fuel gas no norm rma ally conta ontaiins liqu liquiid, the scrubbe ubberr has a dr drain valve that autom automati atically opens at a preset level to em empty the scrubbe ubberr to a liqu liquiid dr drain system tem. At sites whe herre the fuel fuel gas does not no norm rma ally conta ontaiin liqu liquiids, the scrubbe ubberr may have onl only a manua anuall dr drain valve. Because liqu liquiid accumulati ation in the scrubbe ubberr is abno abnorm rma al, any liqu liquiid wou oulld be d drrained manua anualllly to a po porrtab tablle conta ontaiine nerr and di disposed by the Oper Operato atorr. The Oper Operato atorr must per perform form liqu liquiid dr with company safety drainage/di nage/disposal in accordance with procedu edurres and company / regu egullato atorry waste/eff te/efflluent d diisposal polilicies. po The fuel fuel gas scrubbe ubberr has a pr pressure safety valve (PSV) PSV) that opens to relie lieve excessive pr pressure to p prrevent scrubbe ubberr ruptu upturre. Overpressurizing of the scrubbe ubberr can be caused by upstrea eam m regu egullato atorr fa faililu ure.

Additional Fuel Gas Filtration Some line Som line heater heaters may be equ equiipped with with fuel fuel gas fil filttrati ation, dependi depending on the conta ontami minant nant((s) to be removed: To remove solid lids, a meta etall mesh straine nerr or or a par particulate filte ilterr is used. The straine ner’ r’s removab ablle mesh el element can be cleaned and reinstall talled; ed; a par particulate fil filte ter’ r’s inte nterrna nall elements ar are rep epllaceab eablle. To remove liqu liquiid mist, a coa oallescing fil filte terr is used. The coa oallescing fil filte ter’ r’s el elements ar are rep epllaceab eablle.

3.3 Burner Fuel Gas The bu burrne nerr fue fuell gas pi piping/ valving assembly: receives cond ondiitioned fuel fuel gas branches to dir dire ect the fuel fuel gas to the heater’ heate r’s main bur burne nerr and pil pilot ot bur burne nerr cont ontrrols the fl flow of fue fuell gas to ensure safe ope operrati ation of the heater’ heate r’s main bur burne nerr and p pililot ot bu burrne nerr The specific fue fuell gas valving/ cont ontrrol conf onfiigu gurrati ation is dete determi rmined ned ire by regu egullato atorry and insurance requ equir ements and company polilicies. po

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The more stringent ringent requ equir ire ements incorpo porrate a h hiighe gherr level of: safety redundancy burrne bu nerr safety cont ontrrols to auto autom mate bu burrne nerr ope operrati ation and the burrne bu ner’ r’s safe star tartup/ shutdo hutdow wn instrumentat entatiion to enabl enable local and remote mon oniitori toring ng This section describe ribes fue fuell gas valving; Section 4 describe ribes how ho w the valving is cont ontrrolled lled as pa parrt of safe line line heater heater operrati ope ation, star tartup, and shutdo hutdow wn. Figu Figurre 8 sho how ws the main burrne bu nerr and pil pilot ot bu burrne nerr fue fuell gas fl flows. Burne nerr and Pil P ilot ot Bur Burne nerr Fue uell Gas Fl Flo ows Figure 8 —Main Bur

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Fuel Gas Flow to the Main Burner Cond ondiitioned fuel fuel gas fl flows to the bur burne nerr fue fuell gas tr train and passes th thrrough the foll follo owing wing components to feed the main burrne bu nerr: line heater a manual block valve used to isolate the line heater fr from line heater wn the fue fuell gas supp upplly when the line heater is shut do dow ribed late a pilot gas draw off. As described aterr, thi this dr drawoff may be located ei eithe therr upstrea eam m or or do dow wnstrea eam m of the bur burne nerr safety shutoff valve. a press ure regulator that reduces the fuel fuel gas pr pressure to the optim optimu um main bur burne nerr pr pressure. The regu egullato atorr is typically equiipped with equ with a p prressure gauge. one or two main burner safety shutoff valves that autom auto mati atically closes to shut off the fuel fuel gas fl flow du duri ring ng abnorm abno rma al ope operrati ation. Shutti Shutting dow down the ffllow pr prevents an accumulati ation of fuel fuel gas, which cou oulld lead to a line line heater heater explosion. Abnorm Abnorma al ope operrati ation includes:

End of Sam ple A full full licensed copy of th thiis kit includes: • Tra Training Modu odulle and Sel Self-Che -Check • Knowl Knowledge edge Check and Answer Key • Bl Blank Answer Sheet Perform forman ance Check • Per • Job Ai Aid • Exercise The fu fullll version of thi this kit can be pur purchased at: http:// www.hd www.hdc.ab.ca/pu a/purrchase_descri ript ptiion.asp?I p?ID D=37

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Indirect Fired Heater Training Module

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