地瓜干加工废水厌氧生物处理难点及解决措施分析

Analysis on the Difficulties and Solutions of Anaerobic Biological Treatment of Dried Sweet Potato Processing Wastewater

采用厌氧、好氧为主的地瓜干加工废水处理厂,IC反应器出水COD不稳定,污泥解体、破碎,反应器顶部腐蚀严重影响安全运行,经过分析、衡算及查阅文献发现,这些问题主要是由于地瓜干加工过程中加入的1 000~1 500μmol/L焦亚硫酸钠造成的。建议采取提高厌氧进水pH值至7.5~8.0,同时采取合理的废水处理收费机制降低进入IC反应器的焦亚硫酸钠含量,可以缓解焦亚硫酸钠对厌氧处理的不利影响。20 000×10^(-6)~25 000×10^(-6)的硫化氢对IC反应器一些部件及配套设备造成腐蚀,影响安全运行,建议采用SS304或SS316材质,为保证沼气燃烧排放尾气二氧化硫稳定达标,建议采取硫化氢去除率大于99.2%的湿法、干法两级脱硫。

In the dried sweet potato processing wastewater treatment plant which mainly uses anaerobic and aerobic,the effluent COD of the IC reactor is unstable,the sludge is disintegrated and broken,and the corrosion of the top of the reactor seriously affects the safe operation.The problem is mainly caused by the 1000~1500μmol/L sodium metabisulfite added during the processing of dried sweet potatoes.It is recommended to increase the pH of anaerobic influent to 7.5~8.0,and adopt a reasonable wastewater treatment charging mechanism to reduce the content of sodium metabisulfite entering the IC reactor,which can alleviate the adverse effect of sodium metabisulfite on anaerobic treatment.20000×10^(6)-25000×10^(-6) of hydrogen sulfide will cause corrosion to some components and supporting equipment of the IC reactor,which will affect the safe operation.It is recommended to use SS304 or SS316 material.In order to ensure the stability of sulfur dioxide in the tail gas discharged from biogas combustion,it is recommended to adopt wet and dry desulfurization with hydrogen sulfide removal rate greater than 99.2%.