Ahp Presenatation

7/17/2019 Ahp Presenatation

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PRESENTATION ON

ASH HANDLING SYSTEM



WHAT IS ASH HANDLING SYSTEM

Ash Handling refers to the methods of collection, interimstorage , conveying and disposal systems of various types ofash generated from solid fuel combustion process in the boiler.



Coal Consumption / ASH GENERATION in Coal Base

Po!e" Plants

For example, the coal requirements for some typical cases ofpower plants are likely to be as follows :

!"# $% & 'ndian (oal & )#,### *+ - #."# $*+A /

!00# $% 1 'ndian (oal & #,### *+ - 2.# $*+A/

'3'A3 (4A5 *6+'(A556 (43*A'37 # 8 A7H- $ay go as

high as "#8/

74 '3 *H9 A4;9 (A79, *H9 A7H <939=A*'43 %4>5 9 A7

F4554%7:

!"# $%1 ?### *+

!00# $% & @)### *+

3ote1 Ash (ontent in 'mported (oal is quite less and may go

even as low as " to 08 only depending the source of coal.



ASH GENERATION IN STEAMGENERATORS

A7H '7 <939=A*9 '3 ;A='4>7 F4=$7 A3 A* ;9='4>7 54(A*'437 '3 *H9 *H9=$A5 +4%9= +5A3*7.

*H9 >A3*'*6, +H67'(A5 B (H9$'(A5 +=4+9=*'97 4F A55 *H979 *6+974F A7H A=9 'FF9=93*.

*6+'(A5 54(A*'437 4F A7H <939=A*'43C(4559(*'43 A=9 A7 954%:

'/ 4**4$ A7H1 954% *H9 4'59= F>=3A(9''/ (4A=79 A7H & >(* H4++9=7,9(434$'D9= H4++9=7,A'= +=9H9A*9=

H4++9=7'''/ F56 A7H & 954% 97+CFA='( F'5*9= H4++9=7C (H'$396 H4++9=';/ $'55 =9E9(*7 - +6='*97/ & 954% *H9 =9E9(*7 (H>*97 4F *H9 $'557



GRANULAR,MODERATELY HOT,ABRASIVE5 % ( Max)COARSE ASH

VERY FINE,MODERATELY HOT,ABRASIVE80 TO 85 %FLY ASH

IRREGULAR IN SIZE, FINES TOVERY LARGE

SIZE PIECES,VERY HOT, VERY ABRASIVE

0 TO 0 %BOTTOM ASH

GENERAL PROPERTIESAPPRO!"#TY"TYPE OF ASH



*ypes of Ash (ollection 7ystems

@/ ottom Ash Handling 7ystems

)/ Fly Ash Handling 7ystems



*ypes of ottom Ash Handling 7ystem

@/ %ater 7ubmerged Hopper *ype 7ystem

)/ 7ubmerged 7crapper (onveyor 7ystem

/ ry *ype Ash (ollection 7ystem

*ypes of Fly Ash Handling 7ystem

@/ ense +hase (onveying

)/ ;acuumC+ressure (onveying



Bottom As# Hanlin$S%stem

Bottom As# is &olle&te t#"ou$# t#e 'ollo!in$ t!o s%stems ()

$ Wate" impoune t%pe *ottom as# #oppe" s%stemottom ash formed due to combustion of coal in the furnace is collected in awater 'mpounded refractory lined bottom ash hopper. 9ach outlet of bottomash hopper is provided with hydraulically operated feed gates, one clinkergrinder and one et pump. ottom ash collected in the hopper is fed to theclinker grinder where it is crushed to small siGe. *he et pump located below

the clinker grinder conveys crushed ash clinkers to ash slurry sump with thehelp of high pressure water through transport piping. *his is an intermittenttype of system, generally operated once in a shift of sixC eight hours.

$ S&"appe" &#ain &on+e%o" s%stem *his is a continuous type of system. *he ash formed in the furnace is allowed tofall into a dry type refractory lined bottom ash hopper where water is sprayed

to quench the ash. uenched ash continuously falls through the hopper outletsinto the water trough of scraper chain conveyor below. *he scraper feederdewaters the ash and feeds it to clinker grinder. *he crushed ash is conveyed indry form to bottom ash binC silo. *he further disposal from binC silo is by trucks.



,LOW DIAGRAM ,OR WET BOTTOM ASHHANDLING SYSTEM

Water impounded type bottom ash hopper system



Bottom As# Hoppe"



Bottom As# Hoppe"- Outsie.ie!



Bottom As# Hoppe" !it#out Re'"a&to"% Linin$ -Insie .ie!





Bottom As# Hoppe" Seal T"ou$#

Pu"pose

*o provide sealing of oiler Furnace and prevent ingress of outside airinto furnace





,LOW DIAGRAM ,OR DRY BOTTOM ASH HANDLINGSYSTEM

S&"appe" &#ain &on+e%o" s%stem



Cline" G"ine"



H%"o)E0e&to" o" 1et Pump



S&"appe" Con+e%e"



$ Pneumati& S%stem a2 .a&uum t%pe pneumati& &on+e%in$ s%stem ) *he y ash from 97+C

A+HC 9conomiGer hoppers is evacuated using vacuum system. ;acuum is createdusing mechanical exhaustersC vacuum pumps. Air1ash mixture is conveyed toprimary and secondary collectors located at the silo top where ash gets separatedand is collected in the silo.

%here the silos are located far way from the 97+ hoppers, combination ofvacuum system and pressure system is used.

*2 P"essu"e t%pe pneumati& &on+e%in$ s%stem o" P"essu"i3eS%stem

*he y ash from diIerent 97+C A+HC 9conomiGer hoppers is fed into thetransporter vessel. (ompressed air is allowed into the vessel at a controlled rate andthe ash is conveyed to the silo along with the pressuriGed air. *he conveying air isvented through the bag Jlters mounted on the roof of the silo while ash particlessettle in the silo. %ith pressure pneumatic systems, it is possible to convey ash tolonger distances.

,l% As# Hanlin$ S%stem



a2 .a&uum s%stem$ 5ean +hase & Air: Ash ;olumetric ratio @##:@

*2 P"essu"e o" P"essu"i3e S%stem$ ilute +hase & Ash: Air ;olumetric ratio @" to #:@

$ ense +hase & Ash: Air ;olumetric ratio # to "#:@

,l% As# Pneumati& S%stem





As# Sto"a$e Silos

K 7tore Fly Ash for intermediate duration before Jnaldisposal.

K (onstruction from (arbon 7teel or =((.K Aeration 7tone provided at the bottom of 7ilo for

aeration and induce ow from the silo to dischargeoutlets.

K ischarge 4utlets.a/ =emoval of ash in dry form through *elescopic (hute

into (lose *ankers.b/ =emoval of ash in semi1dry form through Hydomix

ust (onditioner into 4pen trucks.

c/ =emoval of Ash in slurry form through hydro eectorC et pump to Ash 7ump for further pumping to ashpond.

,l% As# Hanlin$ S%stem



.a&uum Con+e%in$

45 Ai" Intae

65 ,ull% En&lose7 8ui& A&tin$7S!in$ Dis& +al+e

95 Pipe ,ittin$s !it# Repla&ea*le7Re+e"si*le7 Inte"&#an$ea*leWea"*a&s :;;< BHN2

=5 Pale T%pe As# Conitionin$>nit

;5 A*"asion Resistant &ent"i'u$all%Cast Con+e%o" Pipe

?5 Silo .ent ,ilte"@5 Cent"i'u$al Re&ei+e"/Sepa"ato"5 Pulse 1et Ba$ T%pe Dust

Colle&to"5 Continuous As# Colle&tin$

Dou*le Dump Gates4<5 Silo Relie' .al+e445 As# Sto"a$e Silo465 Ai" Pipe495 ,u$iti+e Dust ,ilte"

4=5 Teles&opi& D"% >nloae"4;5 .a&uum B"eae"4?5 Gua" ,ilte"4@5 Me&#ani&al E#auste"s



.a&uum Con+e%in$) At SiloTop



Teles&opi& C#ute Belo! Silo 'o" D"% As#Remo+al



HYDRO MI D>STCONDITIONER



PADDLE TYPE ASH CONDITIONER





Dense P#ase Pneumati& P"essu"e Con+e%in$ S%stem



.a&uum Con+e%in$) Belo!

ESP

Dense P#ase Pneumati& P"essu"e Con+e%in$ S%stem



Dense P#ase Pneumati& P"essu"e Con+e%in$ S%stem$ +owdered material like y ash, which has a very good uidiGing property and low bulkdensity, can be pressuriGed and uidiGed at the same time to prevent compaction whensubect to pressure. $ *he systems normally have dual operatability either through the timer 4r level probewhich is installed in the collecting hopper.

$ As soon as the ash level reaches a Jxed level in the collecting hopper, the level probesenses its presence, it allows the system to initiate a (onveying cycle. *he inlet valveopens to allow the ash to gravitate into the conveying vessel, till it closes automatically. 4nclosure of the ;alve, the conveying vessel gets pressuriGed and the material =esistancehelps pressure build up which conveys the material through +ipe to the destination silo.%hen conveying is complete which is7ensed by the control system, air supply to the system is stopped and 7ystem is ready forthe next cycle.

$ *he total system operation is automatic by use of level probes in estination silo-s/ tocontrol the transfer of material. Flexibility in the 7ystem allows to opt from single transferof material from one point (ollection to single reception hopper or a multipoint collection.

*he 7ystem is exible enough and programmable and automatically 4perated through a+5( based central control panel.



Dense P#ase Con+e%in$ - As#

T"anspo"te" A""an$ement Belo!

ESP



'n case of combined vacuum and pressuriGed system, the y ash isconveyed under vacuum up to buIer hopper and further transportation

up to dry ash silo is pressuriGed. Fly ash from the 97+ and A+H hopper issometimes extracted through a vacuum conveying system.

Com*ination

.a&uum/P"essu"e As#

Hanlin$ Con+e%in$ S%stems







Compa"ison o' .a&uum +s p"essu"e Con+e%in$S%stem

;acuum 7ystem +ressure 7ystem

When Recommended

(onvey system less than 0#*+H per system High system capacity. =easonable conveying distance. 5ong conveying distance-greater

than @### to )### feet/

Advantages

less maintenance at hoppers. Allow higher capacity 7ystem leaks inward for cleaner environment Allow higher conveying distance.

$ultiple collecting points. 3o separating equipment. 7impler control scheme. (lean air blower multiple disposalpoint .

Disadvantages

=equires separating equipment and process bag ouble gate required with air lock.

Filter. Air lock pressuriGing and venting

requires lower life dependent on separating equipment additional piping and valving reliability Ash leaks outward into the plant.

Higher maintenance costs.



Compa"ison o' Dilute P#ase +s Dense P#aseP"essu"i3e Con+e%in$ S%stem



SL>RRY DISPOSALSYSTEMK ASH S>MP

K For intermediate storage of bottomC y ash slurry & *he ash slurry sump shallbe designed for Jve -"/ minutes capacity to avoid settling of ash in the

sump which in turn causes choking of suction pipe of the slurry pump.K +rovided with Alloy (' liners of thickness )"mm and "#H3 hardness at thebottom of the sump and walls where the ash slurry falls to prevent abrasion

K 7lurry agitation noGGles shall be provided at the bottom of the sump near thepump suction to keep the ash particles in suspension to avoid choking ofsuction line of the slurry pumps.

K ASH SL>RRY P>MPS

K For Jnal disposal of slurry to Ash +ond though pipelinesK (entrifugal pumps & 'f ash: water ratio is #:0#K High (oncentrated 7lurry pumps & 'f Ash: water ratio is 0":"

K ASH PONDK For storage of ash for the complete life of the power plant i.e. )" yearsK Height of pile in the dyke & @? meters L height of dyke is increased in stages.K isadvantage

& =equires very large area for storage of ash& Ash slurry re1circulation system back to power plant is provided to minimiGeash pond overow





CONTROL SYSTEM ,OR ASH HANDLING SYSTEM

$ ,LY ASH SYSTEMPLC BASED SYSTEMAdvantage & +rogrammable (ontrollers has a memory and is programmable,providing the user ability to change the ash handling sequence and timing and givesthe operator the ability to troubleshoot, modify and expand with the system

$ BOTTOM ASH SYSTEMfor safe operation (ontrol (ubicle is installed near the A Hopper



PIPE7 ,ITTINGS AND .AL.ES,OR ASH HANDLING SYSTEM

K A*"asion / &o""osion "esistant pipes an ttin$s o' &ast allo% metalss#oul *euse5

+ipes : ## H3 1 Alloy (ast 'ron +ipesFittings : "## H3 1 Alloy (ast 'ron ends, asalt 5ined ends9xpansion Eoint : ## H3;alves : $aterial handling ;alve, Mnife <ate ;alves, (up ;alves



MATERIAL HANDLING.AL.E

BELOW ESP/APH HOPPERS



ASH >TILISATION

K ,LY ASH ) Cement Manu'a&tu"in$K ,LY ASH ) Builin$ Mate"ials - Cla%)F% as# *"i&s7 Lime)F% as# *"i&s

K BOTTOM ASH ) Const"u&tion o' Roa Em*anments/ Ba& ,illsK BOTTOM ASH ) Mines ,illin$



74$9 4F *H9 =9+>*9 ;934=7 '3 '3'A F4= A7H

HA35'3< 767*9$7 : '3>=9

>((

$A(A%9= 99MA6

*9(H+=4 A7H*9(H



*ypes of Ash isposal 7ystem

@/ ryC%et *ype isposal 7ystem

)/ 5ean 7lurry isposal 7ystem

/ High (oncentration 7lurry isposal 7ystem



THANK YOU

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Ahp Presenatation