바이오필터 모델로서 프로세스럼핑 모델(Lim의 모델)을 넓은 농도범위의 친수성 VOC의 경우에도 유효하도록 robust하게 개선하기 위하여, 수막으로 둘러싸였다고 가정한 멸균된 입상 활성탄, compost 및 동부피의 입상 활성탄/compost 담체 각각에 대해서 모델적용에 필요한 Freundlich 등온흡착관계식의 흡착상수들을 구하고 상호 비교하였다. 당 연구에서는 각각 0.04, 0.08, 0.12, 0.16, 0.2, 0.4, 0.8 및 1.0 ml의 에탄올을 멸균된 각각의 젖은 담체에 첨가하여서 바이오필터 운전조건과 같은 30 oC에서 흡착이 정상상태에 도달한 후에 각각의 담체에 대한 흡착량을 산출하는 에탄올 등온흡착평형 실험을 통하여, 각 담체 내부의 세공에 응축된 물에 용해된 에탄올농도와 등온흡착평형을 이루는 에탄올의 평형 흡착량을 모사하는 Freundrich 등온흡착모델의 파라미터인 흡착능 상수(K) 및 흡착지수(1/n) 값을 멸균된 입상 활성탄, compost 및 동부피의 입상 활성탄/compost 담체에 대하여 각각 0.7566과 5.070×10-7 mg-ethanol/mgmedia/(mg-ethanol/m3)0.7566, 0.8827과 1.000×10-8 mg-ethanol/mgmedia/(mg-ethanol/m3)0.8827 및 0.5688과 5.243×10-6 mg-ethanol/mgmedia/(mg-ethanol/m3)0.5688과 같이 구축하였다. 이와 같은 에탄올 등온흡착평형 실험에서 구해진 흡착능 상수 및 흡착지수를 포함하는 Freundlich 흡착상수는, 바이오필터의 바이오막으로 덮여진 바이오필터담체의 흡착특성에 적용할 수 있었다. 당 연구에서의 에탄올의 공기/물 분배계수와 Delhomenie 등의 젖은 compost담체에 대한 톨루엔 흡착실험에서의 톨루엔의 공기/물 분배계수의, 비의 크기 정도는 compost를 담체로 하는 양쪽의 연구에서 산출된 흡착량 비의 크기 정도와 거의 일치하였다.
Freundlich isothermal adsorption parameters, applicable to such biofilter-model as process-lumping model(Lim’s model), for sterilized granular activated carbon(GAC), sterilized compost and sterilized equal volume mixture of GAC and compost were obtained and were compared each other, assuming that adsorbents are enclosed by water layer, in order to construct robust process-lumping biofilter model effective for wide-range of hydrophilic volatile organic compounds(VOC). In this investigation 0.04, 0.08, 0.12, 0.16, 0.2, 0.4, 0.8 and 1.0ml of ethanol were added to three kinds of adsorbent-media and were placed at 30°… under the wet condition of the media, which was the same as biofilter operating condition, until the adsorption reached the condition of equilibrium before each adsorbed amount of ethanol was obtained. Then adsorption capacity parameters(K) and adsorption exponents of Freundlich adsorption isotherm equation, which simulates the adsorbed amount of ethanol equilibrated with the ethanol concentration of the condensed water in the pore of the media, were constructed for sterilized granular activated carbon(GAC), sterilized compost and sterilized equal volume mixture of GAC and compost as (0.7566 and 5.070×10-7 mg-ethanol/mgmedia/(mg-ethanol/m3)0.7566), (0.8827 and 1.000×10-8 mg-ethanol/mgmedia/(mg-ethanol/m3)0.8827) and (0.5688 and 5.243×10-6 mg-ethanol/mgmedia/(mg-ethanol/m3)0.5688), respectively. These Freundlich isothermal adsorption parameters were applicable to the adsorption characteristics of biofilter media enclosed with bio-layer. The order of magnitude of the ratio of ethanol-air/water partition coefficient and toluene-air/water partition coefficient was almost consistent to that of ethanol-adsorbed amounts in this experiment with compost and in the investigation of Delhomenie et al. on toluene-adsorption to wet compost.
Speitel GE, Mclay Jr DS, J. Environ.Eng., 119, 658, 1993
Liu PKT, Gregg RL, Sabol HK, Air & Waste, 44, 209, 1994
Deshusses MA, Dunn IJ, Modelling Experiments on the Kinetics of Mixed-solvent Removal from Waste Gas in a Biofilter, Proceedings of the 6th European Congress on Biotechnology (L. Alberghina, L. Frontali and P. Sensi eds.), pp.1191-1198, Elsevier Science B. V.(1994)
Eckhart A, Proceedings of Biological Treatment of Industrial Waste Gases, Dechema, Heidelberg, Germany, Mar. 24-26, 2pp.(1987)
Buchner R, “Auswirkungen Verschiedener Betriebszustande in der Biologischen Abluftreinigung am Beispiel von Biofiltern,” Ph. D. Thesis, T. U. Wien, Austria(1989)
Leson G, Winer AM, J. Air & Waste Manage. Assoc., 41, 1045, 1991
Sorial GA, Smith FL, Suidan MT, Biswas P, Journal of the Air & Waste Management Association, 45, 801, 1995
El-Sharkway II, Saha BB, Koyoma S, He J, Ng KC, Yap C, “Experimental Investigation on Activated Carbonethanol Pair for Solar Powered Adsorption Cooling Applications,” Refrigeration, xxx, 1-7(2008)