| Benzene homologue compounds (BHCs) pollution have become a increasinglyserious problem in the petroleum chemical industry, energy transport and indoordecoration and so on. The control technology of BHCs pollution in wastewater and airis a hot topic concerning to people. The research contents of the dissertation were asfollows:1. In this paper, activated sludge and biological packing were collected fromanaerobic tank and aerobic pool of sewage treatment plant for separation andtraining high efficient microbial species with the styrene agar block as the solecarbon source. The study of biochemical characteristics, 16S rDNA sequence andBIOLOG identification were carried out to this strain. The form of the strain isslightly curved, round at both ends, having size of 0.5 ~ 0.7μm×1.5 ~ 2.5μm,with flagellum for motion. It is gram-negative, color not obvious, facultativeaerobic, optimal growth temperature 25℃~35℃, optimum pH range of 6.0 to 7.5,triple sugar iron test K/K, oxidase-positive. The strain was identified aspseudomonas aeruginosa named MJ001.2. The effects of growth factors to microbial strains MJ001 such as temperature andpH were studied in styrene and toluene solution. The efficiency of styrene andtoluene degradation were analysed on different temperature and pH. Themaximum biomass of MJ001 was found at 30℃, pH=6.5 and the highdegradation efficiency of styrene and toluene was found at 30℃, pH=6.5 too. Itindicated that MJ001 in styrene solution of 1 mg/L ~ 7 mg/L grew well within 24h. The maximum microbial biomass was obtained when styrene concentration gotto 4 mg/L. MJ001 biomass able to be stabilize within 24 hours in toluene solutionunder 5 mg/L while it could not reach stable period within 24 hours in toluenesolution above 5 mg/L. The degradation efficiency of styrene and toluene in alltesting concentrations reached 92% or more in 24 hours. From the degradationkinetics analysis point of view, the degradation reaction followed first gradekinetics.3. The five days biochemical oxygen demand improved a lot after adding strainMJ001 to actual wastewater samples. The BOD5/COD values doubled or more.General microbial film and MJ001 microbial film were compared on thedetermination of BOD in wastewater. The value of BOD using MJ001 nearly doubled compared to the general microbial.4. Purification efficiency of biological filtration tower is mainly influenced byempty tower time, inlet toluene concentration, humidity and so on. When the gasflow was 0.1 m3 h-1, 0.2 m3 h-1, 0.3 m3 h-1, 0.4 m3 h-1 (empty tower residence timeof 85 s, 68 s, 51 s and 34 s), toluene removal efficiency was 90% still. Whentoluene inlet concentration was 100~300 mg m-3 (empty tower residence time of85 s), the degradation efficiency reached 90%. When the gas humidity was above20%, high degradation efficiency of toluene obtained. The measurements ofbiomass accumulation and CO2 concentration of inlet and outlet were used toverify carbon assimilation of microbial on toluene. Three-dimensionalfluorescence spectroscopy technology was used and the main product of thetoluene degradation was initially judged to be organic acids.
|
PDF Full Text Request