土壤微生物法处理汽修厂喷涂废气的研究

发布时间：2018-03-25 16:15

本文选题：土壤微生物　切入点：汽修喷涂废气　出处：《重庆工商大学》2017年硕士论文

【摘要】：汽修喷涂废气是一类常见且对人体危害很大的气体。微生物法处理废气技术的研究在水溶液处理中较为普遍,在合适的操作条件下,处理低浓度恶臭废气可以获得较高的去除效率,且无二次污染产生。土壤微生物法处理汽修厂喷涂废气从理论上可以达到相同或者优于现有废气处理技术的处理效果。因此用土壤微生物装置降解汽修喷涂废气的研究具有较大的理论和实践意义。本研究以苯、甲苯为主要特征污染物代表汽修喷涂废气,从土壤中筛选出能高效降解苯和甲苯的真菌,对降解效果好的菌种进行鉴定和降解条件的优化,以期得到高效处理汽修喷涂废气的微生物;设计了专门的土壤微生物废气处理装置,研究了该装置挂膜前后的流动阻力特性。分别考察了以锯末:黏土(3:1),锯末:谷壳:黏土(1:1:2),黏土:谷壳(3:1)混合填料条件反应装置对不同浓度的甲苯废气的去除效果,以及不同湿度时各种条件填料对甲苯的降解效率。本研究采取加油站附近和油漆厂附近的土壤为真菌菌源,通过筛选得到两株苯和甲苯高效降解真菌Z1和H1。用ITS法进行鉴定,H1为土曲霉菌较易降解甲苯,Z1菌为烟曲霉菌较易降解苯。研究表明,土曲霉对甲苯有良好的降解效果,烟曲霉对苯有良好的降解效果。对土曲霉菌降解甲苯的温度、pH和初始底物浓度的单因子试验结果表明,土曲霉菌在第8d对初始浓度450mg/L和4500mg/L的苯的降解率分别为78.56%、33.96%,说明菌种对低浓度底物降解有较好效果。土曲霉降解甲苯的最适温度为30℃,最适pH为4.0。对烟曲霉菌株降解苯的温度、pH、初始苯浓度、吐温80添加量4个因素进行了正交试验。结果表明菌株烟曲霉菌降解苯的最佳条件为200mg/L,温度为30℃,pH为4.0,吐温80添加量为0.5mL/L,在该条件下烟曲霉菌对苯的最大降解率为80.4%,降解率明显高于未驯化前。在研究中设计了一套土壤微生物处理系统,并通过运行对处理系统挂膜前后的流动阻力特性进行了试验研究,结论如下:在塔内填料高度一定时,随着气体流量的增加,压力损失也增加;随着生物膜的增长,气体的流通空间减小,相对气速增大,压力损失也增加;挂膜后过滤塔内气侧流动阻力远大于挂膜前的流动阻力,气侧流动阻力的变化可作为判断微生物生长情况的依据。考察了装置在不同甲苯进口浓度情况下的去除效果,考察了三种不同混合比条件下填料的降解效果。实验结果表明:三种条件下对甲苯有良好的去除率,其中锯末和黏土的混合条件下能达到最好的降解效果。在甲苯进口浓度100 mg/L,填料含水量为300g/kg时,最大去除率接近90%。装置的去除速率与进口负荷与甲苯去除率有关,当进口浓度300mg/m3,流量2.4m3/h时,最大去除负荷能达到4.8g/m3·h。研究表明锯末和黏土混合作为填料时对高浓度的甲苯有较好的降解能力。通过对填料的不同含水量下三套装置对甲苯的净化效率的研究,得到结果:填料含水量对去除率的影响较大,对三种填料的影响的总体趋势是填料含水量越高降解效率越高。
[Abstract]:Automobile exhaust gas spraying is a kind of common and great harm to the human body. Research on gas biological treatment technology for waste gas is more common in the water solution, in the appropriate operating conditions, treatment of malodorous waste gas in low concentration can obtain higher removal efficiency, and no two pollution. The treatment effect of soil microbial treatment of auto repair factory exhaust gas spraying can theoretically achieve the same or better than the existing technology for waste gas treatment. Therefore research on degradation of aftermarket exhaust gas spraying device of soil microorganism has great theoretical and practical significance. In this study, benzene, toluene as the main representative of automotive exhaust gas spraying characteristics of pollutants, screened from soil degradation efficiency of benzene and toluene in fungi optimization, identification and degradation conditions on the degradation efficiency of good bacteria, in order to get the efficient processing of automotive exhaust gas spraying microorganisms; special design Soil microbial waste gas treatment device, flow resistance characteristics of the device. Before and after the biofilm were investigated by using sawdust: Clay (3:1), sawdust: rice husk: Clay (1:1:2), clay: rice husk (3:1) on the removal of toluene with different concentrations of the mixed packing conditions of reaction device, and different humidity variety the conditions of toluene filler on degradation efficiency. This research adopts the gas station nearby and paint factory soil fungus source is obtained through screening two strains of benzene and toluene efficient degradation fungi Z1 and H1. were identified by ITS method, H1 a.terreus easily degraded toluene, Aspergillus fumigatus strain Z1 was easily degraded benzene. The study shows that the soil have a good effect on the degradation of Aspergillus fumigatus with toluene, good degradation effect of benzene. The a.terreus toluene degradation temperature, single factor test results of pH and initial substrate concentration showed that Aspergillus terrus in section 8D of The initial concentration of 450mg/L and 4500mg/L on the degradation rate of benzene was 78.56%, 33.96%, indicating that the bacteria had good effect on the low concentration of substrate degradation. The optimum temperature is 30 DEG C a.terreus toluene degradation, the optimum pH for 4.0. of Aspergillus benzene degradation temperature, pH, initial concentration of benzene, the orthogonal test of Twain 80 the addition of 4 factors. The results showed that the optimum conditions of Aspergillus fumigatus strain degradation of benzene is 200mg/L, the temperature is 30 DEG C, pH 4, Twain 80 adding amount of 0.5mL/L, in the condition of Aspergillus fumigatus on benzene maximum degradation rate was 80.4%, the degradation rate is obviously higher than that before domestication is designed. A set of soil microbial treatment system in the study, and through the operation of the experimental study on the flow resistance characteristics of membrane hanging processing system before and after the conclusions are as follows: the tower height, with the increase of gas flow rate, the pressure loss will increase with the biofilm; The growth of gas circulation space decreases, the relative gas velocity increases, the pressure loss increases; biofilm filtration tower gas side flow resistance is far greater than the flow resistance of biofilm before the change of gas side flow resistance can be used to determine the microbial growth basis. The removal effect in different inlet toluene concentration under the condition of device study the effects of three kinds of different mixing ratio degradation results under conditions of packing. The experimental results show that under the three conditions of toluene removal is good, the sawdust and clay mixing conditions can achieve the best effect of degradation. The inlet toluene concentration of 100 mg/L, the water content is 300g/kg, the maximum removal rate close to the 90%. device removal rate and import load and removal rate of toluene, when the inlet concentration of 300mg/m3, flow rate 2.4m3/h, the maximum removal load can reach 4.8g/m3 and h. studies showed that sawdust and clay mixed cooperation For the high concentration of toluene on the filler has better degradation ability. Get the results by different water content of filler under three sets of equipment research, the purification efficiency of toluene: the water content has great influence on the removal rate, the overall trend of the influence of three kinds of filler filler is more moisture in the degradation efficiency high.

【学位授予单位】：重庆工商大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X701

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