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

The effect of temperature on denitrification and short-cut denitrification 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.