Membrane Bioreactor for Control of Volatile Organic Compound Air Emissions

用于控制挥发性有机化合物空气排放的膜生物反应器

• 批准号: 9530592
• 负责人: Sarina Ergas
• 金额: $ 17.07万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 2000-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9530592&HistoricalAwards=false
• 关键词: Membrane; Bioreactor; Control; Volatile; Organic

9530592 Ergas Biofiltration is a low cost and effective method for controlling emissions of biodegradable volatile organic compounds (VOC's) from chemical and process industries. Studies and field applications of these systems, however, have been limited to inlet VOC concentrations of less than 1,000 ppmv. At high inlet concentrations, microbial growth results in plugging of biofilter media pore spaces. In addition, these systems are of limited use where degradation results in the formation of acidic metabolites or where cosubstrates must be added to induce enzymes required for cometabolism. To overcome the limitations described above, biological treatment systems for VOC control must be developed which: 1) incorporate mass transfer of VOCs across a media with high specific surface area and low diffusion length, 2) incorporate high biomass concentrations to maintain high biodegradation rates, 3) provide a method for wasting biomass to prevent clogging, and 4) provide a method for addition of pH buffers, nutrients, and/or co- substrates to support the microbial population and neutralize acidic metabolites. A specially designed bioreactor is under investigation which has the potential to meet these requirements and achieve high VOC removal efficiencies in small reactor volumes. The reactor utilizes hydrophobic microporous hollow fiber membranes for mass transfer. Gases containing VOCs are passed through bundles of hollow fiber membranes. Soluble compounds in the gas phase are transferred through the membranes to the surrounding liquid nutrient media. Compounds in the liquid phase are then available for biodegradation. The proposed project will further investigate the use of microporous hydrophobic hollow fiber membrane systems for biological treatment of gas phase VOCS. Specific objectives include: investigation of factors controlling mass transfer and biodegradation; investigation of conditions for use in cometabolism of the model chlorinated VOC, tr ichloroethene; refinement and testing of mathematical models of mass transfer and biodegradation.

9530592 Ergas生物过滤是一种低成本和有效的方法，用于控制化学和加工工业中可生物降解的挥发性有机化合物（VOC）的排放。 然而，这些系统的研究和现场应用仅限于入口VOC浓度小于1，000 ppmv。 在高入口浓度下，微生物生长导致生物过滤器介质孔隙空间的堵塞。 此外，这些系统在降解导致酸性代谢物形成或必须加入共底物以诱导彗星所需酶的情况下使用有限。 为了克服上述限制，必须开发用于VOC控制的生物处理系统，其：1）引入VOC穿过具有高比表面积和低扩散长度的介质的传质，2）引入高生物质浓度以保持高生物降解速率，3）提供浪费生物质以防止堵塞的方法，和4）提供一种添加pH缓冲液、营养物和/或共底物以支持微生物种群和中和酸性代谢物的方法。 一种专门设计的生物反应器正在研究中，它有可能满足这些要求，并在小反应器体积内实现高VOC去除效率。 该反应器利用疏水微孔中空纤维膜进行传质。 含有VOC的气体通过成束的中空纤维膜。 气相中的可溶性化合物通过膜转移到周围的液体营养培养基中。 然后，液相中的化合物可用于生物降解。 本项目将进一步研究利用微孔疏水中空纤维膜系统对气相挥发性有机化合物进行生物处理。 具体目标包括：研究了控制传质和生物降解的因素; 2研究了氯化VOC、三氯乙烯模型的共沸条件; 3改进和检验了传质和生物降解的数学模型。