混合金属离子对厌氧生物处理过程抑制作用的研究

Study on the Inhibition of Mixed Heavy Metals to Anaerobic Digestion

研究了在厌氧生物处理中同时存在铜、锌、镍和铬多种重金属离子时．其对厌氧生物过程的影响；考察了不同日加入金属总量与抑制程度的关系。当日加入总量低于２０ｍｇ／Ｌ时，对体系无影响；在２０—３０ｍｇ／Ｌ时，产生轻微的抑制；高于５０ｍｇ／Ｌ时，对体系产生明显的抑制作用。为维持厌氧生物过程正常运行，每ｇ污泥（干重）所承受的由每日进料引入体系的混合金属离子的总量应不超过０．６ｍｇ；厌氧体系中的溶解态金属总量应低于１．０ｍｇ／Ｌ．实验还表明，混合金属离子对厌氧体系的抑制作用比单个金属离子要强。

he inhibition of mixed heavy metals(copper,zinc,nickel and chromium)to the anaerobic system in adigester,and the relationship between theconcentration of heavy medals daily added and thedegree of their inhibition were studied. No inhibitionwas found when the daily addition of mixed heavymetals was less than 20 mg/L.The digestion systemwas slightly inhibited when the daily addition was20-30mg/L;was seriously inhibited when thedaily addition was more than 50 mg/L;and was innormal operation when the ratio of the concentrationof heavy metals daily added to that of activatedsludge(dry matter)was less than 0.064 % and thetotal concentration of dissolved,mixed heavy metalsin the system was less than 1.0 mg/L. The resultsshow that mixed heavy metals had a much strongertoxicity to an anaerobic system than each of thesingle heavy metals.