Study on the Treatment of Airborne Isopropyl Alcohol (IPA) by Biofilter Packed with Fern Chips

• Main Authors: Chin-wen Jiang, 江欽文
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/45464597860920528827

碩士 === 國立中山大學 === 環境工程研究所 === 93 === Abstract Biological processes have been proven to be economical and effective for control of VOCs with concentration of <1,000 mg C/m3. This study armed to develop a biofilter packed only with fern chips for the removal of airborne isopropyl alcohol (IPA). A three-stage down-flow biofilter (2.2 m in height and 0.4 m×0.4 m in cross-sectional area) was constructed for the performance test. The first stage serviced as a humidifier for the incoming gas and the following two stages, both packed with fern chips with a packing space of 0.30 m × 0.40 m ×0.40 m, as trickling bed biofilters for the VOC removal. Air with a nearly constant IPA concentration of 100 mg/Am3 (@ an average temperature of 34 oC) and a flow rate in the range of 100-400 L/min was fed to the reactor in Phase I test. The flow rate gave an empty bed retention time (EBRT) in the range of 12-48 s for the gas flowing through the two bed media. Solutions of urea-N, phosphate-P, and milk powder were supplied daily to the fern chips for the microbial nutrition in Phase I experiment which lasted for 26 days. Following the Phase, Phase II test operated with a constant EBRT of 12 s and without any nutrient supplementation for 30 days. Experimental results show that with an influent gas temperature of 29-40oC (average 34 oC) and relative humidity of 43-93% (average 73%), with a proper moistening of the bed media, the effluent gas could achieved a temperature of 26-35oC (average 29 oC) and a relative humidity of 98%. The proceeding medium experienced a greater moisture variation (12-68%, average 38%) than that (65-82%, average 72%) of the following one. The former and the latter media had pH in the range of 6.11-7.78 (average 6.77) and 6.13-7.36 (average 6.59), respectively. With no additional nutrient supplementation for 30 days, approximately 98% of the influent IPA of 100 mg/m3 could be removed at the EBRT of as short as 12 s which corresponded to a loading of 60 g IPA/m3.h.