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wrstiaLes t_arnun oakiand 1 511a 639 7762 P.@3
<br /> I tMP Sf3 QPP
<br /> RE$1 ES RI131 1x151 Er ^' ars .. t:: �± F• :T�s ;�:xxr j
<br /> kP4�5+tf r C! g `t �+v S - Q� �d '
<br /> t I. Go6onaIM9hel1 carbon
<br /> � + JTri chlorOle
<br /> tfsylenIt ,
<br /> Coat-ba.%O l Carbon, E3ertien I !
<br /> S I?' I
<br /> Acetone €
<br /> r#1
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<br /> ,: .: .fz i4 104 11,400 t0�04 a .OD,fJ00 ;.:;-' a;: r�
<br /> .t }} :31D w y}l0. !'SU 6!) � "74;•..•�D' � i
<br /> �: Porgy r !s)s,e;gstroms "`I Reiailtre
<br /> i
<br /> hiriltait
<br /> Y f .RH +? `.:,.
<br /> VIM.s�t�rclewlcz
<br /> ' FIGURE 1(1; l.fDilfierent sfltrrces nrr,.t¢antivatkct carbon with vaslly different pore structures-Micrepgr�sity is:wefl daVlNoped in
<br /> VWXCOwt-shell ;4'C#nost',portes int the t-MA range),While coal-baSed carnons h#!ve severai zones n!mesa-and macropaNsity;By M
<br /> PICttfAg the d rh4ti4es of pare voiunme'f!and radius,these relative differences In parostty charactivi etks are then#uatad-
<br /> FlG1JSE 2(C Ill Since:the retatitre qumidity of 1he YQC s"arn hinders carbon's adsorpflarl cap�lcEly,saps must b7 taken 1O
<br /> rninirhfze the m unt of mgistUre in thr inftent stream
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<br /> i titinefi faQax;`1elforrMatidn of earlaoiis aigttificant water retention a$RE tops tore, and show�Eects of W6'oh the
<br /> t with;welt ae eked.rnicrtrgorosity aid 50%.At this point, tapiIlary condensa- adsorption of behxene! ,
<br /> rttrrrun►Stafa4.•e axx a , tion becomes important, and it in-
<br /> VOC adsull Ptil by activated carbon creases with increasing RH until the .MuIti talenteii Este
<br /> is a physical prReess,invoNing vain der microporous structure of the cai7bon is Carbon•adsorpWri technologies .for I ;
<br /> j Waals force Yliis.weak'exotherrt}ie cam ylete}y filled with.water. VQQ removal .foqus .6n two!:applies-
<br /> i -ir; e4cm l' r�tc's between 2 ands 5 T6 reduce the effect of RH an $ tions:The recov,�ery of valuable indus-
<br /> 'kcalhnole of eitr carbon's adsorption capacity, the M04- 'trial solvents for risuse,and the remov-
<br /> 1 A.;phenozo noii called tapilIary con- tore:content of the stream can be xe- al of VOCs for air_�Ou ttion cflntral and .
<br /> .dens tion ows eerbil .carbons tri dix4d in ore of two ways,Because All purification. j 4
<br /> hold; e YpC I at,a Capacity bf is a strong function of the gas tempera- To ensure a0inpteti'jtpted operation,
<br /> 3U�++ar more f#Meir weight[x].As t ie tore,the gas stream can either be heat =bon-hued systems are noritially op-
<br /> arbo n-b sedsems
<br /> I play a big role
<br /> I ' l . j
<br /> ! in pollution :prey n#ioh
<br /> and solvent reaorery
<br /> eeatoantrad ' of the,VOC,in the ZL- ed by 20 lyp,or,it can be cooled funs �
<br /> erated in'a cyclic p nein Adsoron is
<br /> s eous;snc eaples,multiple laye�s ' to condense out moisture,and then re- switched betwe6 two Meds,so that one ' I
<br /> of orie ol ic compound iiuild up bu heated to reduce the relative humidity is regenerated 4ile;the cther is in '
<br /> the walls of W''hotx livres. At still to below 50%. service. Regeneration, is initiated at.
<br /> highitr VOCj•oneentrations,this build- Since carbon adsorption is an eso= cording to a timed addorption jcyde, or j
<br /> ulp.iAtimatel' causes VO Cs to collect' therink process, adsorption efficiency when breakthroll (xhe fust detect,
<br /> a tquid in tli sm.allbst pores_ ! will be reduced as the temperature of able appearance of the organic cam•
<br /> The rel" h74m'l i and t ei r ' the stream being treated is increased, pound in the adsorber efflll has I ! I
<br /> perature of. ie VOCr'`ladeit Sim=also Por this reason,it is preferable to re- been observed. 1
<br /> direly affe the'Carbo? "s ability 4 duce RH by chilling, so that a cooler To restore the"spent"bed its origi-
<br /> ,adsu,I and z of l h organic levels- stream ig delivered to the Carl]o3l Keds. nal fartn,.a gaseau{�regenerating agent I
<br /> The;sdsozpt� n ;oapacitg is;diminished In general,the efffect of temperature. is.passed thronglx it at elevated tem- 1 I
<br /> signif tan ly asi the";RH of the VOC on a caabon's adsarption capacity is' peratures.Theadsorbe�VQCz>z'aleculea � !
<br /> Weim exc s50 (pYgut a 2). considerably legs than the effect of rel- am desurlied and callerted far�disposal, ,
<br /> A idok at vlrltex�tsothgm curve for ative humidity.Figtlres.d.axed a provide or for further tmatmeiit and reuse.
<br /> a "I--based carbo '( igvre 3) shows a comparison of the RH and tempera- I?eg)endiug an the C{?nstrgi,itS or re i
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