乙二醇污水预处理生物流化床工业试验研究

乙烯水解生产乙二醇过程中,会产生大量乙二醇污水,该污水有机物浓度高,COD值高达1500～4000mg/L,污水中含有乙二醇、二乙二醇、醚类、醛类有机物质,对微生物具有一定的毒性。上海石化利用生物流化床技术,开展乙二醇污水预处理工业试验研究。试验结果表明,在污水pH值为5.5～11.0,温度为25～30℃,反应停留时间为10～15h,进水COD值为1000～3000mg/L条件下,处理后COD值小于500mg/L,达到企业预处理标准,COD去除率达到90%,流化床污水处理系统抗COD、pH冲击能力强,运行较为平稳。与传统氧化沟处理工艺对比,流化床工艺的反应效率、出水水质均优于氧化沟工艺,停留时间仅为氧化沟法的1/4。研制出大型生物流化床处理乙二醇污水工业试验装置,该装置主要包括均质水解罐、生物流化床、加药罐和空气压缩机。该装置最大容积负荷达到6.0kg COD/(m3.d),平均容积负荷达到3.1kg COD/(m3.d),是传统氧化沟法平均容积负荷的4倍。生物流化床工艺实现了污水处理的装置化、集成化,且占地面积小,操作费用低,处理效果好,抗冲击能力强。

A Study on Industrial Experiments on Glycol Sewage Pretreatment Using Biological Fluidized Bed

The process of producing glycol by hydrolysis of ethylene will produce a large amount of sewage con- taining glycol.The sewage has very high concentration of organic matters--COD value is as high as 1500- 4000mg/L--and contains organic matters such as glycol,diethylene glycol,ethers and aldehydes,with certain toxicity to microbes.Sinopec Shanghai Petrochemical Company conducted an industrial experiment study into using bilogical fluidized bed technology to treat glycol sewage.The exerimental results show that when the pH of sewage is 5.5-11.0,temperature is 25-30~C,reactor residence time is 10-15h and the COD of fed water is 1000-3000mg/L,the COD of treated water is lower than 500mg/L ,which meets the company＇s standard for water pretreatment.The experiment shows that 90% of COD was removed and that the fluidized bed sewage treatment systme has strong COD and pH resistance capacity and has been operating stably.Compared with the conventional oxidation ditch technology,the fluidized bed technology has higher reactor efficiency and quality of water treated and its residence time is only one fourth of that for the oxidation ditch technology. Sinopec Shanghai Petrochemical Company has now developed a large industrial experiment unit for treating glycol sewage using the biological fluidized bed technology ,the main components of which include a homoge- neous hydrolysis tank,a biological fluidized bed,a chemical agent feeder and an air compressor.The maximum working load of the unit is 6.0kg COD/（m3＂d） and its average working load is 3.1kg COD/（m3＂d）,four times the average working load of the conventional oxidation ditch method.The biological fluidized bed technology makes it possible to treat sewage all in a unit and in an integrative manner,featuring small floor area re- quired,low operating cost,good treatment effect and strong impact resistance.