New Technology Research On Petrochemical Odour Treated By Compound Bio-filter Bed

With the increase of people's environmental consciousness, the demand forenvironmental quality is becoming higher and higher. People are more sensitive to thepollution induced by odour. At present, some petrochemical enterprises located in large andmedium cities, whose odour pollution has affected their existence and development. For theodour pollution status of wastewater treatment plant in petrochemical enterprises, apreliminary study on using compound bio-bed technology to treat the"compound odour"gases which was simulated by laboratory was conducted.In this experiment, the activated sludge domesticated was acted as the deodorizingmicrobial strains base, from which some highly effective deodorizing strains were isolatedand purified. The cultivating conditions of highly effective deodorizing strains were optimizedthrough a series of single factor and orthogonal experiments. The highly effective deodorizingstrains were also identified initially. The highly effective deodorizing strains activated in theoptimal conditions were inoculated to the wood, ceramic, activated carbon and pumice fillerto hang film. The deodorizing depuration effects and various parameters'changes ofdeodorizing operation were compared. The stability of different deodorizing systems was alsodiscussed initially.In this experiment, a highly effective ammonia-nitrogen degrading strain AD-4, a highlyeffective sulfide degrading strain S-5 and a highly effective toluene degrading strain JBJ-3were isolated from the domesticated activated sludge. The optimal activated temperature, theoptimal activated pH, the optimal activated shaking-bed speed and the optimal activatedinoculation volume were identified through investigation. Inoculating highly effectivedeodorizing strains to four kinds of fillers, the time needed of hanging film were relativelyshort for wood and pumice, the biomass all reached more than 50nmolP/g filler after 22~23d, but for activated carbon and ceramic, the time needed for hanging film were relatively long.The biomass could reach more than 40nmolP/g filler after 29～30d. In the conditions of 2L/hcirculating nutrient solution flow rate, 0.3m3/h compound odour gas flow rate, H2S, NH3, andtoluene inlet concentrations of 100mg/m3, 100mg/m3 and 200mg/m3, the removal rate ofdifferent fillers to various odour gases were all more than 80% and did not exist thedomesticated period required by common activated sludge. This showed that the highlyeffective deodorizing strains screened occupied a dominate position in the stable ecosystemformed by compound bio-filter bed. Different strains of interlinked and mutually reinforcing,and mutual restraint to maintain the stability of deodorization system.After the compound bio-filter bed operated two months, the pressure drop of the systemfilled with wood filler was lowest, only 390Pa. After the device outaged two weeks, the timeneeded for complete restoration of system filled with wood filler was the lowest, only 6h. Thisshowed that the deodorizing system filled with wood filler had a more adaptive capacity tothe change of in-site conditions.This study showed that it was feasible in technology to treat low concentration'H2S,NH3, and toluene compound odour gas through artificially screened highly effectivedeodorizing strains. The high performance wood filler was screened through comparinghanging film period, the deodorizing purification effect and various parameters'change forthe deodorizing operation of different fillers in deodorizing operation, which could providepredominant strains and high performance wood filler for in-site pilot experiment. So, thishad a certain environmental, economical and social value.