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With the development of the petrochemical industry, and its by-products on the environment caused by pollution worsening, one of the most representative volatile organic compounds (VOCs). VOCs contain many compounds have harmful effects on human health and the natural environment, and purification of VOCs has caused widespread concern. VOCs various treatment methods, biological trickling filter method of its low investment, low operating costs, high efficiency, stable operation, easy management, and no secondary pollution, people of all ages, in the treatment of VOCs. good prospect. Daqing Petrochemical Company, a factory wastewater pretreatment device the VOCs as processing object, respectively, the design of single-stage and three biological trickling filter its purification and isolation and identification of the tower packing microbial count the trickling tower microbial structure. Experimental results show that when the pH was kept at 6.3 to 6.9, the temperature at 12 ~ 25 ° C, the trickling filter with the removal efficiency of VOCs into the gas concentration increases and reduced; when the gas flow rate increased from 0m ~ 3 / h to 10m ~ 3 / h, the removal rate decreased; increase in the amount of liquid spray can improve the purifying effect of the trickling filter, spray volume of 25L / h, the removal rate. ZAT-2-type filler as fill media trickling filter, compared to a slight increase in the removal efficiency of benzene, toluene and xylene and plastic composite pompon. The single-stage biological trickling filter for waste gas treatment, the removal of benzene, toluene, xylene, and total non-methane hydrocarbons were 98.2%, 98.8%, 98.8% and 96.7%. The three biological trickling filter, the removal of benzene and total non-methane hydrocarbons were increased to 99.4% and 97.4%. Three biological trickling filter processing results of the actual exhaust, benzene, toluene, xylene, and total non-methane hydrocarbon removal rates were 98.2%, 98.7%, 94.6% and 98.7%; export concentration of 8.3mg / m ~ 3,4.0 mg / m ~ 3,4.3 mg / m ~ 3 and 14.9 mg / m ~ 3 have reached the national atmospheric pollutants emission standards. Removal load of benzene, toluene and xylene were 98.2 g / (m ~~ 3 · h), 60.3 g / (m 3 · h), and 12.0 g / (m ~~ 3 · h). Microbial count results show that the stable operation of the 20d of the single-stage biological trickling filter, filler upper on the number of colonies in the next three positions were: 2.7 × 10 ~ 6 cfu / g, 2.9 × 10 ~ 6 cfu / g and 3.0 × 10 6 cfu / g; underlayer upper, middle and lower three parts strains respectively to 3.0 × 10 6 cfu / g, 3.1 × 10 6 cfu / g and 3.2 × 10 to 6cfu / g microorganisms The number increases with the decline in the height of the filler layer. Screened the strongest two bacteria, VOCs removal after colony morphology observation and physiological and biochemical tests, we can see its genus to genus Pseudomonas (Pseudomonas) and Brevibacterium (Brevibacterium). 16SrRNA gene characteristics of the V3 region fragment of microorganisms after DGGE separation, sequencing, account for 12.0% of the total, with of Arthrobacter (section bacterial genera) of Xanthomonas (yellow Aeromonas spp) similar sequence is filler on the advantage flora. According to the the Shannon index calculation results of the microbial diversity in the trickling filter packing gradually increasing from top to bottom. Wastewater pretreatment device in accordance with the actual monitoring results, the plant produced biological treatment of the exhaust system with a the biological pretreatment tower tertiary biological trickling filter, the treated gas into the atmosphere by high-altitude emissions tower. Humidity greater than 95% of the feed gas, the temperature at around 30 ° C, pH = 6 to 7, the intake flow rate is stabilized at 10m ~~ 3 / h, the amount of circulating fluid spray stable at 40L / h, the optimum circulation liquid spray time for each intermittent the 180min, spray 3min. By the project's technical and economic analysis, we can see the engineering construction projects, total investment of 9.6133 million yuan, an average annual increase after the implementation of the project, the total cost of 1,163,900 yuan.
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