氨三乙酸对废水厌氧消化过程中产甲烷的影响

Effect of nitrilotriacetic acid on methane production during anaerobic digestion of wastewaters

在连续运行的槽式搅拌反应器(CSTR)中考察了氨三乙酸(NTA)对厌氧消化反应器运行效果的影响.在中温35℃条件下,有机负荷化学需氧量(COD)为1.0～3.4g/(L.d)时,NTA的添加可使CSTR反应器COD去除率增加,产气率提高20%～42%,反应器中厌氧污泥的辅酶F430和F420浓度分别提高了1.33倍和24%;采用荧光原位杂交技术(FISH)对古细菌和甲烷八叠球菌进行了检测,结果表明:NTA还促进了甲烷八叠球菌的生长.作为微量元素螯合剂,NTA增强了微量元素镍的生物可利用性,优化了产甲烷菌的营养条件,强化了产甲烷菌对微量元素的生物吸收,对厌氧消化反应具有促进作用.

Abstract： The effect of nitrilotriacetic acid（NTA） on anaerobic digestion in a continuous stirred tank reactor（CSTR） was investigated. At 35 ~C and organic loading COD rate of 1.0--3.4 g/ （L · d）, the COD removal efficiency was improved and biogas yields were increased by 20%-- 42% by addition of NTA. The contents of coenzyme F430 and F420 in the anaerobic sludge were increased by 1.33 times and 24%, respectively. The archaebacteria and methanosarcinaeeae were detected by a fluorescence in situ hybridization（FISH）. The results show that NTA stim- ulate the growth of Methanosarcinaceae. Due to the addition of NTA, a trace metal chelating agent, the bioavailability of trace metal such as nickel is increased and the nutrient condition is optimized for methane production bacteria（MPB）. The biouptake of trace metal for MPB is strengthened. NTA has stimulative effect on anaerobic digestion.