UASB反应器处理糖业废水的运行条件的研究

Study on the Operating Conditions of UASB Reactor for Sugar Wastewater Treatment

本实验探讨UASB反应器在稳定运行阶段时的各项工程应用参数,并探究了氮源的种类、含量对反应器运行的影响.实验将赤糖拟作废水中的底物,添加氮磷元素.COD去除率最高达41.51%,产气量最大值为6.50 L/d,氢气占发酵气体总量的比例最高为62.28%.液相末端产物中,乙醇和乙酸的含量最高,是典型的乙醇发酵类型.研究氮源含量的影响阶段分别向UASB反应器中投加有机氮源(牛肉膏、酵母膏)和无机氮源(氯化铵、硝酸钠).每种氮源添加质量依次为0.5~2.5 g.温度、HRT与稳定阶段保持一致,对产氢量、pH、COD去除率等进行监测.对比认为有机氮源(特别是酵母膏)促进效果好于无机氮源,并且氮含量=1.5 g时最佳.因此,在用UASB反应器进行厌氧发酵产氢时,添加有机氮源并适当调节氮含量可以提高氢气生产的效率.

In this experiment,various engineering application parameters of UASB reactor in stable operation stage were discussed,and the influence of nitrogen source type and content on reactor operation was explored.In the experiment,brown sugar was used as the substrate in wastewater,and nitrogen and phosphorus were added.The highest COD removal rate was 41.51%,the maximum gas production was 6.50 L/D,and the proportion of hydrogen in the total fermentation gas was 62.28%.The content of ethanol and acetic acid was the highest in the end products of liquid phase,which was a typical type of ethanol fermentation.Organic nitrogen sources(beef extract and yeast extract)and inorganic nitrogen sources(ammonium chloride and sodium nitrate)were added to UASB reactor respectively.The mass of each nitrogen source was 0.5〜2.5 G.The hydrogen production,pH and COD removal rate were monitored.The results showed that organic nitrogen source(especially yeast extract)had better promotion effect than inorganic nitrogen source,and the best nitrogen content was 1.5 G.Therefore,the efficiency of hydrogen production can be improved by adding organic nitrogen source and properly adjusting nitrogen content in UASB reactor.