【作者】 陈景光；

【导师】 金春姬；

【作者基本信息】 中国海洋大学 ， 环境工程， 2003， 硕士

【摘要】 高浓度果汁废水具有污染物浓度高、SS高、pH低、水质水量变化大的特点，近年来果汁废水产生的污染也日趋严重。本试验对高浓度果汁废水处理进行了研究。本课题来源于某果汁废水处理的实际工程，针对性强，这对于类似高浓度果汁废水的处理具有较高的参考价值和应用价值。 本试验利用实际工程设施，对比研究了三种工艺：混凝、UASB、水解酸化+接触氧化工艺。试验研究目的在于通过对高浓度果汁废水处理工程工艺的研究分析，找到一条切实可行的技术路线。分析废水COD、BOD、pH、SS等指标的去除效果和变化规律，得出该工艺的最佳设计和控制参数。 试验研究表明，采用水解酸化+接触氧化处理工艺处理果汁加工产生的高浓度有机废水是技术可行的。系统稳定运行时，进水COD浓度变化较大，最大为11220mg／l，最小为2600mg／l，平均为7500mg／l，SS在5800mg／l～2200mg／l之间，平均值为3000mg／l。系统出水COD稳定在150mg／l～40mg／l，平均为127mg／l，平均去除率为98.3％；SS稳定在100mg／l～60mg／l，平均为93mg／l，平均去除率为96.9％。在进水水质波动较大和进水水量增加的过程中，系统的出水水质较稳定，表明系统抗冲击负荷能力强，具有较好的稳定性。 与UASB+接触氧化工艺相比较，水解酸化+接触氧化处理工艺有较大的稳定性和优越性。UASB失败的原因在于运行不稳定，穿孔管布水系统易堵，因此布水系统的合理设计对于UASB的良好运转是至关重要的，采用穿孔管布水是不可取的。 本试验研究对废水进行了混凝处理实验，实验结果表明：与PAC、PAM相比，硫酸亚铁+石灰乳对COD的去除率有较大提高，但沉渣较多。在技术经济上较为合理的加药量为250mg／L，相应的COD去除率为35％，SS去除率为85％，这个实验结果表明，果汁废水中的COD大多为可溶性COD和胶体，去除这部分COD只能依靠生化池。 工程实践表明：水解酸化对于去除高浓度果汁废水中的SS是起关键作用的，对于氧气的削减和节约能耗也是起重要作用的。水解酸化池的SS去除率占总去除率的44.8％。占最大的比例。此外，通过水解酸化改善了高浓度废水的生物可降解性，因此水解酸化池在本工艺流程中至关重要一 一段接触氧化池和水解酸化池在工艺流程中COD去除率起主要作用，这两个池子对COD的去除占COD总去除率的63．3％。M段接触氧化池的去除率相对较小，仅占总去除率的10．5％。 工程实践表明，果汁废水营养成分单一且州低，采用生化法处理，必须对废水投加营养元素氮，调节pH。 采用接触氧化法处理高浓度果汁废水，设计使用二沉池，对于保证调试初期减少投加菌种的流失是起关键作用的。在正常运行时，对于增加接触氧化池的的微生物含量也起一定作用，这使得接触氧化池出水的稳定性增加，出水处理效果有所提高。 根据实际工程运行观测的结果，采用水解酸化十接触氧化处理果汁废水，水解酸化池的最佳容积负荷为8二73kghOD／tnd，接触氧化池的最佳容积负荷为3·473kgCOD／m＼d。 对于果汁废水处理，格栅的预处理作用是很重要的，建议最后一道细格栅设计为性能优越的机械格栅。对于部分高浓度的果汁废水（COD＞10000mw），例如冲罐水，建议单独设计混凝反应池进行预处理。更多还原

【Abstract】 This research, which has taken from a real engineering project, is focused on the treatment of syrup wastewater with high COD, high SS and low pH.With actual engineering facilities, performances of three kinds of process, such as UASB, coagulation, hydrolytic acidification -biological contact oxidation process, are compared and operation problems are discussed. The objectives of this research are to choose the most effective wastewater treatment process and to optimize the design control parameters.The results show that the hydrolytic acidification -biological contact oxidation process is feasible to treat high-strength syrup wastewater. Even if the wastewater quality and quantity change greatly, the system showed very good stability.The hydrolytic acidification plays an important role to remove SS and reduces energy consumption. The removal rate of SS in the hydrolytic acidification reactor is 44.8%, which is the highest rate of the removal in the all process units. Through the hydrolytic acidification, the biodegradability of wastewater is enhanced.The first biological contact oxidation reactor and the hydrolytic acidification reactor play an important role in the removal of COD, where the total removal rate of COD is 63.3%. But the removal rate of COD in the secondary biological contact oxidation reactor is only 10.5%.The engineering practices shows that, it is important to have a reasonable water distributor for UASB system and not feasible to use a bore pipe as a wastewater distributor.The results get from coagulation experiment shows that FeSO4 and lime milk are able to increase the removal rate of COD, but causes lots of sludge. The removal rate of COD reaches 35% and SS reaches 85%, when adding 250mg/L reagent to thereactor. The result also shows that the larger part of COD in the syrup wastewater is soluble.It is necessary to design and use secondary clarifier in treating the syrup wastewater. The secondary clarifier makes the key function to reduce the losing of biomass in the startup stage. In the steady stage, the secondary clarifier makes a function to increase biomass quantity in contact oxidation reactor, at the same time, it will improve secondary effluent quality.It also shows that, it is necessary to add the nitrogen as nutrient and regulate the pH because the wastewater’ s nutrient component is single and pH is low.According to me actual operation results, the optimum volumetric loading of the hydrolytic acidification reactor is 8.273 kgCOD/m3.d, and of the biological contact oxidation reactor is 3.473 kgCOD/m3.d.The screening pretreatment is also important in the treatment of the syrup wastewater. It had better to design mechanical screen with high performance as the last fine screen. As to some high organic strength wastewater, such as flush water (COD>10000mg/L), it is necessary to use separate coagulation reactor as pretreatment process.更多还原