【作者】 曾凤；

【导师】 胡翔；

【作者基本信息】 北京化工大学 ， 环境科学与工程， 2011， 硕士

【摘要】 厌氧发酵液中碳氮比例失调,碳源严重不足、碱度不足、可生化性差,为发酵液后处理工艺的难点。针对这一问题,本研究提出用水解酸化与生物接触氧化循环串联工艺处理发酵液废水。在此基础上,运用离子色谱仪、荧光光谱仪、紫外光谱仪等先进仪器,追踪监测在不同条件下反应过程中有机物和氮元素变化过程。研究了水解酸化与生物接触氧化组合循环工艺处理厌氧发酵液的最佳运行工况和最佳运行参数以及工艺低温运行的性能。试验结果表明,水力停留时间24小时、循环比1：3、温度在8-30℃,溶解氧和有机负荷分别在2mg/L～3mg/L、<3g/L的条件下,组合工艺达到最佳脱氮效果,出水清澈无异味。组合工艺连续运行三个月以上,污染物去除效果稳定。小分子有机酸分析结果显示,在水解酸化过程中,有机物被降解为甲酸、乙酸和丙酸,在水解初期有机酸总量达到最大,随后逐渐降低,后趋于稳定；而在生物接触氧化池内未检测到小分子有机酸物质。荧光光谱分析显示,污水中有机物均以类蛋白类物质荧光峰为主,类蛋白物质的荧光峰强度随着水解时间增加而增强,而好氧过程中有机物中出现结构复杂的类富里酸荧光峰,且逐渐增强。紫外分析结果表明,紫外光谱图中均在280nm处有一个吸收平台,随着反应时间的延长,水解污水中的紫外吸收强度有少许增加,而好氧阶段却呈相反趋势,两者的变化均不明显。水解阶段,SUVA254、E253/E203数值由1.5和0.28增至1.4和0.3,有机物芳香性和不饱和性增加,同时芳环物质的稳定性变差,好氧阶段呈下降趋势,易降解有机物被快速消耗。循环比1：3条件下产生的有机酸物质最佳,脱氮效果最佳。水解酸化阶段污水的COD量与有机酸生成总量、乙酸、丙酸量均呈显性相关关系。污水中有大量的有机物和氮元素抑制磷的去除,并且存在聚糖菌与聚磷菌微生物的竞争机制,聚磷菌无法大量繁殖,影响除磷效果。更多还原

【Abstract】 The difficulty of treating anaerobic digested wastewater is its characteristics on the imbalance of carbon and nitrogen, serious lack of carbon source, lack of basicity, and no good biochemical quality. Aiming at solving the problem, study proposes using a combination recirculating system of hydrolyze-acidification and biological contact oxidation process to treat digested wastewater. Basis on these, study recurs to some advanced instruments such as ion chromatograph, fluorescence spectroscope and ultraviolet spectrometer to detect the changes of organic matter and nitrogen in different condition around the reaction process.The operating conditions and operating parameters of optimal process were studied on the denitrification cycling process combination with hydrolysis & acidification and biological contact oxidation to treat with anaerobic fermentation of digested wastewater. Results showed that hydraulic retention time with 24h, the recycling ratio with 1:3, DO concentration with 2-3mg/L and organic loading with 3g/L were the best running conditions, and then effluent clear and no objectional odor. The combination recirculating system was used to treat digested piggery wastewater for more than three months; the pollutants removal efficiency was continuously stable.Micromolecule organic acid results showed that during hydrolysis and acidification process, organic was degraded to be methanoic acid, acetic acid and propanoic acid. At the beginning of hydrolysis and acidification process, the total organic acid concentration reached maximum, and than reduced, at last it stayed relatively constant. Organic acids were not detected in aerobic reactor. Fluorescence spectroscope showed that organi matter was main protein-like fluorescence, the fluorescence intensity increased gradually in hydrolyze and acidification reactor. However, in aerobic reactor, fluorescence peak of DOM appeared fulic-like fluorescence, and the fluorescence intensity strengthened gradually.Ultraviolet spectrometer results showed that there is a absorption platform in 280nm in ultraviolet spectrum chart, along with the reacting time, it was a little increase arounding in hydrolysis process, but opposited in aerobic phase, both are not obvious. SUVA254 and E253/E203 increased respectively from 1.5 and 0.28 to 1.4 and 0.3 during the hydrolyze reaction, which suggested that aromatic and unsaturated compounds slightly increase and the stability of aromatic compounds weaken. It was declined, and easily degradable organic matter have been degraded rapidly in aerobic reactor.It was produced most organic acid and get a best effect in denitrification in the condition of recycling ratio with 1:3. The concentration of COD was significantly correlated with the concentration of organic acids, acetic acid and propanoic acid in hydrolyze and acidification reactor. A mass of organic matter and nitrogen in effluent were restrain removaling phosphorus, and it exists the competition mechanism of glycogen-accumulating organisms and phosphate-accumulating organisms, causing phosphate accumulating organisms can’t grow greatly, then affected the phosphorous removal effect.更多还原