厌氧氨氧化菌富集培养物对羟胺的转化研究

Hydroxylamine conversion by anammox enrichment

摘要:

摘要：【目的】羟胺是厌氧氨氧化的重要中间产物，本研究旨在探明厌氧氨氧化菌对羟胺的转化特性。【方法】采用厌氧氨氧化菌富集培养物，以羟胺和亚硝酸盐为基质进行分批培养试验，检测反应液中基质和产物的消涨情况。【结果】不接种厌氧氨氧化富集培养物时，羟胺和亚硝酸盐具有化学稳定性，彼此不发生化学反应；接种厌氧氨氧化富集培养物后，羟胺和亚硝酸盐发生化学反应；反应过程中有中间产物氨的产生和转化，最大氨氮积累浓度为0.338 mmol/L；液相中总氮浓度从起始的4.694 mmol/L降至结束时的0.812 mmol/L，转

Abstract:

Abstract: [Objective] Hydroxylamine is an important intermediate product of anammox. This study was focused on the characteristics of hydroxylamine and nitrite conversions by anammox enrichment. [Methods] The changes of nitrogenous substrates and related products with time were measured using batch tests with anammox enrichment as inoculum. [Results] Since hydroxylamine didn’t react with nitrite in uninoculated control culture, these two compounds were chemically stable. Both of them decreased with time in anammox enrichment inoculated cultures, in which ammonia as intermediate product would be produced and converted with the maximum concentration being 0.338 mg/L. The total nitrogen concentration decreased from 4.694 mmol/L to 0.812 mmol/L with conversion rate 82.7 % in the end. When hydroxylamine and nitrite concentrations were about 2.5 mmol/L respectively, the maximum specific sludge conversion rates of hydroxylamine was 0.535 mmol/(gVSS.h), which was 1.81 times bigger than that of ammonia in ammonia reaction system; the maximum specific sludge rate of total nitrogen was slightly higher than that in ammonia reaction system. When hydroxylamine concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 26.7% and 120.7% respectively; and the maximum ammonia accumulated was 1.810mmol/L. When nitrite concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 6.9% and 9.0% respectively; and the maximum ammonia accumulated was 0.795 mmol/L. [Conclusion] Anammox enrichment was capable of converting hydroxylamine and nitrite simultaneously and had the higher conversion rate of hydroxylamine than ammonia conversion rate. Hydroxylamine and nitrite conversion rates were less affected by increase in nitrite concentration, but more significantly influenced by increase in hydroxylamine. The maximum ammonia concentration accumulated would rise as the result of increasing both hydroxylamine and nitrite. The result of experiment was consistent with pathway model presented by van de Graaf AA.