Is a wide range of the influence of temperature on the microorganisms, although (50 ℃ ~ 70 ℃) in the environment of high temperature and low temperature environment (5 ~ 0 ℃) is also active in a certain class of bacteria, but the vast majority of microbes in wastewater treatment is the scope of the optimum growth temperature of 20-30 ℃.
In the appropriate temperature range, the physiological activity of microorganisms is vigorous, and its activity increases with the increase of temperature, and the treatment effect is better.
Beyond this range, the microbial activity deteriorates and the biological processes are affected.
In general, control of reaction process of the highest and the lowest limit of 35 ℃ and 10 ℃ respectively.
(2) the gel group disintegrates and the treatment effect deteriorates rapidly.
(3) dissolved oxygen.
For aerobic biological reactions, it is essential to maintain the concentration of dissolved oxygen in the mixture.
When the dissolved oxygen in the environment was higher than 0.3mg/l, the facultative bacteria and aerobic bacteria were all aerobic respiration.
When the dissolved oxygen (do) is less than 0.2 to 0.3 mg/l was close to zero, facultative bacteria in anaerobic respiration, basic stopped breathing, the vast majority of aerobic bacteria and some aerobic bacteria (mostly filamentous bacteria) may also grow well, after an advantage in systems often result in sludge bulking.
In general, the dissolved oxygen at the outlet of the aeration tank is suitable for maintaining around 2mg/l, which is too high to increase energy consumption and economically uneconomical.