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wes;ates tarban uakland 1 510 639 7762 P.OS I i
<br /> is eq I, the heat 1of vapari�ation of. effective recovery and disposal of this pot is pass thtaugh s.bad of activate d.
<br /> E the . organic..cprapound;plus the dilute stream must be considered. carbon. After a fixed�tune, or whe#
<br /> it heat tting of the caxbo4 surface In Cousin.instanWX -- when inlet breakthrough pectlrs, the stream-i.
<br /> I (lite h t eleased as the adsorbed mole :concentration are significantly higher switched'to "P' thi r W, so the rrs�
<br /> ectil pread� out;on the eaibon sur- than 700 ppmv,for example--thermal 'bed can be!regenerate�3.The choice I ,
<br /> fa*, he heat of ire tIIlg is related to incineration begins to compare favori regeneratizig coltditiosss and r'egenerai-
<br /> i til tyres*of ad�trbed ori ably as an alternative technology to ing ageatsi depends ol� the aonditione
<br /> ganic cod nd 'by the CIaasius-Cia- contra]VOC emissions. Cleas'ly, incur described elarlier.
<br /> e uniiZe
<br /> r 8-1 is $
<br /> e' uslbon. ',l�Iis calculation can Bratton should not be considered for The op . oqp sYs# op .
<br /> j
<br /> p Kl
<br /> be.ti d t�'esttmatk the energy require would-be pollutsmts that can be reccv-. when the follovnng eotsditians are me}:
<br /> mere fob'tli6 sysl:eln. erect as valuable solvents. Tho chos6h mon l�as�a high working
<br /> S'xat'�ir�of.ties VOC*s a fund capacity;'*6 rates 11or regeneratink
<br /> :. .tion: f oleculat.* 4eight arid atonic Three commercial,systems stesrn or 94 axe low, . d,a retso,silhlp
<br /> strut red, certaitl nrgarue cgmpounds, Several innovative 'VOO-recovery sys-' sepat'gtion and VT y of tate VOC
<br /> will.; e ads$rbed; artd reta.iped more terns using GAC have}peeneommercial- can be attainelt. j
<br /> read.[ than[Othdls'.Systems;handling. i..ed recently.Three competing'tecbnol- Direct sYcarriigg of the Carbon'bed
<br /> strori ly j adsgrl compounds require ogies are discussed below: the most i widely used reg &a
<br /> i hlgll xt¢reaemboil ternpc�tures to
<br /> 'i":` ;'�i ri�,a'�� '' ,:.t';i` ny}:.� `�i'r= ��•_ ri?'?S'.r- ;:5":�^'�:+'::�.. �,`-.ks f
<br /> strip nl}ect'd VOts and restore the M
<br /> I actin tet[carbon to is Usable Corm.
<br /> in, ditian, because bigher-boiling- i,y cstion r ;
<br /> RYi-mo T ,
<br /> pQir�t corpxpol>zads are less,volaizle they , _ !
<br /> WaslQWater inlet RHr80°� Od s#redtn g ,
<br /> will' r;tore`'difficti3t t+o strip Brom the . ' - : ': .'.'.• '' ,
<br /> tax n. Prolonged Ircgerfer8tion times lnl! RH54°� Stripped ;
<br /> ' • miry.�s called fcrr;t6 siislod a low vola- � ,�' = : ' '- _!cnnrlertsate
<br /> g l�irster� '-$trtpp�t!" a
<br /> alit p�eetiies;this will increase costs saturator]
<br /> VOC I
<br /> alid netip y 'equireaents, l '
<br /> stmarn
<br /> Ie�.McconoentTmfsor!4_Solvent
<br /> re e ,using activated Carlson is usA- Coclrefei~:
<br /> alt effcctivfe bcn inlet6ncentra, } cprrenf
<br /> y, pp Carbon
<br /> tion' axe 740 Pa?u per rnill�arn by vol a!r stri er adsorhers 1
<br /> usne pp>7v)
<br /> or gre4ter. At �
<br /> i
<br /> cone trations bela'w 700 pprnv,solvent
<br /> tact cry may not 5e e-oonorAicany'fes
<br /> ase wo*ug capscitic•a are i
<br /> j laws eel IeWs sr�-high,and high Vol. Steam
<br /> time of re enetatiian agent are ONO ; Steam 0 fi !
<br /> reqi Ter -- -- r lean gas WM'
<br /> eollawing'conditions;favor the _i_. from sYsleni
<br /> Clean water out Rec}+cte'loop for mripping air Or n1lTogen i
<br /> p' table !recwe y .of a particular +
<br /> I VO : A simple:vapor stream (where . f Stripping agent
<br /> a>�l"
<br /> on,e-11
<br /> i1C is present),rntinirnal par- '
<br /> i• # ttl�Ifter,iinlEt terrft3P,r9tttres less FiGLIRE 6.All of the elements of the opee�-and close�icop ra�avery systetnns Are tint
<br /> same,except for one:#n the open-taoA d ign,clean gas coming alE the earhnn:best is
<br /> th } pr0istnte ef£icii[tt adsorb vented. Ir tits cfased4oup design. it is;recycled k-c thOugh t1Ae casmter 't", {
<br /> tion, Ibw relative humidify (<5495); . stripper,wbich separates voce from inflittent wastewater*kwl sends the vapor 62geam
<br /> acid voc I'nceut�ations 45%of the on to the canon beds a
<br /> I love r eplosiz� limit(lL` . '
<br /> uge,VpC;�for sir-pollution can-
<br /> open-loco VOCreeovery.finis syr- rrlotlysd,siac�'it is inep�pensive az�d sipo• ;i
<br /> tool inlet cdncenkr tions betivee>a 3 0 anti tem,typically used in conventional sol- pie.The Steam[,required do the i
<br /> 70� pp�nY air bP l ed In much tYce vent recvi�ery, captures VOCs from volume nature a�the nrtak al Eq�be
<br /> ss vfay. Ss st►lvpntrrecaverg systems. wastewater arnd air streams(Figure 6). sttippeO A certain amount is net i
<br /> H' evef, at su6:lovv inlet concentra-. • It earl easily Ice :sealed from several irlltially to raise the temperature c►f
<br /> t rc�rbC, }5e[l collas very low hundred to mute than 2tf,OQ{l Ib of acti- had to pCismo decor stiox+ Mores ml . • }
<br /> toe
<br /> �70c'. aind regeneration 1 rated carbon per adsorber bed Chari- isthen itee ed to reduce tfle p ef€llze t rte nts.The cast- " dling from 50 to 10,{)00 :sefm of pressure;of.tine VOCs in the adsu erg
<br /> so they can be swepi out of the
<br /> f throughput}. ;
<br /> b mL OnidkmYon of an In Air In A countercurrent air stripper sept- For solveriGracgvery spat ems,sly l k
<br /> 8+E3r �pta�srm caa atvtiiti5 a snw�o g,3itiam
<br /> l >c°13°6 t 4� ax-�a rates VOCs from the incoming wash- les sbaw that the optimum sty useW eft .. E
<br /> w;th 8 9b balsa end�Alt inert fi—above
<br /> e>ss� ,ter► ��# water stream. The resalt ing VOC vA- i5 between 0:25 incl 6.�Ila of steam I
<br />
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