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wC3 va Lu,S %,ov Jurt UUK l arTU 1 711�J ty�y 't`!b f,ki6
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<br /> 11,of cad on,
<br /> I; =a a flpwlrate of 114 lb! ,>..:.� :i; s ,c{ FIQUFt�7
<br /> the .
<br /> In rtu co fern-
<br /> �7MIin}( t A tho ngli disemibn bf all .> �� �kt'
<br /> s�orptioa r genera6M 'con6idex S#rrpprng ;,Goolrng I x 1 gator.Ybcs>xre
<br /> j iiia: huentionalsolventrecxWCanaeeemeted :,agent i. :strm sri Heat :. . ;i,...` ,a+yniinuixrsly ad`
<br /> desorption "supply: sorbed ior�ta 1h
<br /> systie ig p ri"elsewhere[Y] eftluerrt ;coMu carbon-
<br /> 4 d- op� ete llr�covaI4. F,.,. �' Glean ges I castedee�Ta .
<br /> C nti�ri t .S. `nviionmental F otec- t " *eap ghee!
<br /> 1 systsrn! C4oi,amall portion
<br /> hfln Age, ey ('E3?A; l fa Kington. D.C.J Desorption i of the fluenz
<br /> coni"rng;
<br /> deterztuti d j Ih$t ben ne ezni$sianS zone zone stream s continu-
<br /> jh,6M vas us .p sailrces went a sinifi ; uusly p seed I
<br /> caxtt risk t+�; 'u an health. Never!stair Aft lion througrl.a po!•rlem.ofi
<br /> Nu zine
<br /> dards;at mrnd'ted bythe IM!Clean It ThisLe.
<br /> is#urtheted Ins
<br /> Air Aab•' rn�ridments ad des<Aed byheal anger;acrd
<br /> Na nal l�liSSipn Standards for is usedlas the tl�
<br /> T3a�ard s Air R6lluta (N ESk1 AFS), = Sporn, agent so,
<br /> i-. i '
<br /> specify p r-�zuss� le benaene limns. x j contin mealy re"n.
<br /> A cl d-loop,!benzene-re unit P g „ate a�pbrtion of.
<br /> r°" .."' :,a ! e wheel
<br /> «ran help to ki.2�tatuiu'pollution c�ntrol ! 1
<br /> standard 1 [ his S3rgtem, alsd illus- I i
<br /> tratedir# Pi u=e16,was a riginallydevel- voc
<br /> oped to eat: 8trei3W:I front Stream- Honeycomb
<br /> r'efinery? pera bns. It�can be used to structure i
<br /> recover eta*t and o cr VOCs from Drive motor
<br /> a^ea=Selbu Own iTokyb3 l ! f
<br /> A F j e fic �Gy,nitrogen s Ihipper'. i I
<br /> tint sty s e and.other hy- Regeneration should be initiated generated zone to,'mam the desired rr
<br /> clrocarbd ft tgAhe,ef.luentwastewa- once a threshold level of VOCs has operatiisg teff iperatures ach of the M
<br /> Ur.Tf>e� �JC.s k then cogUtion- been detected in the recycled gas- zones is tigitly'Isea�led(against tele l
<br /> Qtly to " br R11�below 1 76.The stream stream.-this level,typically on the or- wheel,, to .keep ;the alfeatns from I
<br /> is first d td condense the water der of 10 ppm, is determined by the omnmingling.!
<br /> vapor•,'; d t 10. f reheated by 201trF. minimum equilibrium limits that=be As 'the VQC stream f]tws thx+ou is i
<br /> s ereladsorbed by onelof the tolerated in the water discharge from the.carlwa-costed`. eyc Crab;or nic I ;
<br /> two ' on Beds, *r Wtht relatively clean the stripper. To minimize rapid VOC ' aoinpounds arh removed adsorgti.ml
<br /> gas exi` g. :e adsorb(r is reated breakthrough,the regenerated carbon A,low volumelof hot stir Tanother hot
<br /> to the:ini t o tl cottn er-current strip- beds should be cooled before being gas(typieally 115 to 1116 of the volume:
<br /> to.1011,
<br /> nt iruously°strip VOO$ from brought back ore line. of•the tre nt s rM) passosit;wa tea r �3'hile�e bed The benzene-recovery unit can.rap• through the tion ctor in the
<br /> is in adr 't or) made, the other is re- tune benzene and other VOCs frcr�m : .opposite dtrecticia of tine s I
<br /> generaby �steaan stripping, Th, waste stre�lmc, ranging from 350500 : stream,dewing collect d VM and.
<br /> sate stream is recy- gpm, creating effluent streams r�ith dontSntsously regeiteratan a portion of r�tier�y for. f�lrther discharge levels of 50500 parts per bil• the wheel, nth one co plete rovolu-
<br /> p lion by weight (ppbw), Captured ben- tion,the entirO wheel is rfgeiierated.
<br /> %P... nsfxogexi his occasionally zene and other organic solvents can be The deso6tioA effluent contains
<br /> j31ed _trhe �adsarl!{ion vessels, to recovered far reuse.Sin4e#l►e annual. stripped VOCs at 5 to x5 times the ;
<br /> purge crrplecula eigklt hytiromr- cost of nitrogen is relatively low; the td>seentratioa; of the original praaess
<br /> ;-tons; t aft n concentrate 4n the use of this inert gas is recommended stream.This aancentrated VOGstrelsin '
<br /> closed-l' p eagtar.Suleh a buildup can. closed Ioop systems, to eliminate the can be praces�eci to recoer or remove 1
<br /> ;adverse 'hpapt a?lsnr stioxt eff�iency- risk of VbC ppncetttratiUns approach- collected soly,nts'by furt er eatbbn ad i
<br /> 0 rs s ecifyir, the closed-loop Ing
<br /> tion orleombustion.
<br /> LEI,levels. soroon,refrigeration .
<br /> ':systerdl f l-refin� applications : Rotor conoenfxatot ' o recover' Ifydmp-topic zeolites c ate ineorlia- I i
<br /> �inusf cp tend th impurities, such as VOGs from gas phase waste streams, rated into the surface aiiati►� of the
<br /> ulfdx aqd reave aerosols,and low- this system uses a corrugated wheel, honeyootnb wheel. This particularly
<br /> .volabli angu iccoinpeuads.ilieseim whose ceramic hoieycomb structure useful where VOCs e)dstin d2lute Gori:
<br /> purltie ark no !eas�'lyl remaverl inuring ho lbeen coated with powdered activat- centrations in staesrns tarth high Tela'
<br /> :;rage flirt, pd will ultimately re, ed carbon Wig�tre 7).The wheel rotates Live humidity Th rotoritechnolbgy is i
<br /> I 'dare tlg vro�k ng cap4acity of car continuously,at a slow speed, and is widely used tv cotxtml solventvapors iri
<br /> ban,; . ultStkg�tnpr�ftequent iegenar- divided into three sones-••-ane fqr ad- Frvsntuag applications in the sircrb%ftaxul ; .4
<br /> atioii nd' an- ancrOase in system sorption,ane for desorption{regenera- automobile industries[ '
<br /> tion), and the third far cooling the rOperii , g �•
<br /> e- The following factors ltnust be coni .
<br /> F
<br /> I
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