氨三乙酸促进厌氧消化产甲烷的动力学研究

以乙酸钠为碳源,考察了金属离子螯合剂氨三乙酸(NTA)对厌氧发酵产甲烷过程的影响.结果表明,NTA对厌氧消化具有明显的促进作用,在乙酸钠浓度为6,7,10,12g/L,消化温度为35 ℃的条件下,10μmol/L NTA的添加,分别使甲烷产量提高了30.0%,45.2%,64.3%和95.9%.此时, NTA促进厌氧消化反应的动力学常数V max和半饱和常数Ks分别由84.8mLCH4/(gSS×d)和2.95gNaAc/L提高到147. 1mLCH4/(gSS×d)和7.57g NaAc/L.螯合剂NTA的添加,使微量元素的生物可利用性得到增强,产甲烷菌对乙酸盐的利用率相应提高.

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

Using sodium acetate as substrate, the effect of metal ion-chelating agent, nitrilotriacetic acid (NTA), on methane production in the process of anaerobic digestion was investigated. NTA had stimulative effect on anaerobic digestion. At 35℃, addition of 10 μmol/L NTA enhanced methane production by 30%, 45.2%, 64.3% and 95.9% with sodium acetate concentration of 6, 7,10 and 12g/L, respectively. The kinetic constant Vmax and half-saturation constant Ks for anaerobic digestion was improved from 84.8 mL CH4/(gSS×d) to 147.1 mL CH4/(gSS×d) and 2.95 gNaAc/L to 7.57g NaAc/L, respectively. Due to the addition of NTA, the bioavailability of trace metals for methanogens and the acetate utilization rate in anaerobic batch reactors were dramatically increased.