温度对反硝化过程的影响以及pH值变化规律

Effect of temperature on denitrification and profiles of pH during the process.

以乙酸钠为碳源,采用序批式反应器（SBR）考察了不同温度对全程和短程2种类型反硝化的影响.结果表明,在温度为10-30℃时,2种类型反硝化均可以进行完全.相同温度下,短程反硝化的平均比反硝化速率是全程的1.312倍.降低温度,2种电子受体的比反硝化速率均会下降,且20-10℃的温度转变较30-20℃转变的影响显著,其中以NO2^- -N的还原过程受低温影响较大.低温（10-15℃）条件对NO3^- -N向NO2^- -N的还原过程有一定抑制作用.在起始电子受体浓度与pH值相同的条件下,温度越低,反硝化过程中2种系统pH值增量越大,反硝化结束时的pH值越高;温度相同条件下,短程反硝化结束时pH值曲线上峰点的值高于全程反硝化.

The effect of temperature on denitrification and short-cut denitriflcation with additional carbon source of acetate in a Sequencing Batch Reactor （SBR） was investigated. Two types of denitrification proceeded drastically and the average specific denitrification rate（rDN）of short-cut denitrification was 1.312 times greater than that of denitrification under the same temperature. With the decrease of temperature, both specific denitrification rates slowed down, whereas the change of 20-10℃ had greater influence on two types of denitrification than that of 30-20℃ and the denitrification of nitrite was influenced by low temperature even more greatly. Besides, the reduction of nitrate to nitrite was inhibited under the range of 10-15℃. When the initial concentration of electron acceptors and pH value were same, pH value produced in the two systems increased with the decreasing of temperature and the apex on pH profile of short-cut denitrification was higher at the same temperature.