Environmental Factors That Affect The Yield Of Activated Sludge

Activated sludge treatment is the biological treatment extensively applied in city sewage plant, and is the traditional technology for biochemical treatment method for wastewater. But there is a malpractice during the operation, which produce large quantity of residual sludge. The investment in sludge treatment account for 40～50% of total investment of wastewater treatment plant, although the sludge production quantity just 1～2% of the wastewater being treated. As the final disposal for sludge is a hard work, and in order to prevent the secondary pollution produced by the sludge, the most effective measure is to cut down the produced sludge quantity by improving and alteration of the technology. So it is necessary to study the environment effectors to activated sludge production ratio (real yield and observation yield) and analysis the relative significance of each factors in order to lessen the sludge production through adjust the environmental factors.An improved OUR equipment was put forward in this paper, and was used in rest measurement. The effects of different environment conditions (temperature,substrate,heavy metal and uncoupled metabolism) to Yobs, YH and Kd were investigated systemically. According to the series of studies above, a number of main conclusions can be drawn as follows:1. A new device of measuring OUR was designed, and the real yield(YH) and Kd measured with which are match to the YH and Kd reported in some literatures. And this indicated that the OUR of organic wastewater can be measured using this device comparatively exactly.2 For the Yobs and YH to starch,protein and phenol, there are same orderliness of starch > protein > phenol, which showed that there are higher yield for more degradabel medium. And both YH are higher than the corresponded Yobs, these maybe because the YH not susceptible to predatory, death, regeneration and so on. The different type of medium in influent can result in the change of microorganism makeup, and result in different cell yield and ,which is the ultimate reason for...