强化生物除磷系统除磷特性对水温变化响应的试验研究

Effect of water temperature variation on phosphorus removal characteristics in an enhanced biological phosphorus removal system

以富集聚磷菌(Phosphorus Accumulating Organisms,PAOs)的活性污泥为基础,研究了强化生物除磷(Enhanced Biological Phosphorus Removal,EBPR)系统的磷酸盐去除特性对温度升高和恢复的响应.结果表明,水温从20℃分别上升到25、30和35℃3种状态持续运行8d后,EBPR系统厌氧释磷和好氧吸磷受到明显抑制,系统磷酸盐去除率显著下降.20℃对照处理系统的磷酸盐去除率约为80.3%,而35℃的升温处理其磷酸盐去除率为0,说明此系统处于崩溃状态.当所有处理系统水温恢复到20℃运行后,25℃处理系统经过1d的恢复,磷酸盐去除率可恢复至80%,30℃处理系统经过5d的恢复,磷酸盐去除率可达80%,而35℃处理系统则无法恢复到原来的状态.此外,水温上升到25、30和35℃分别运行8d后,系统内厌氧胞内聚合物(PHA)的合成量和好氧PHA的消耗量随着反应器内水温的升高而增加.20℃对照处理系统的厌氧PHA合成量约为0.03mg·mg-1(以污泥计,下同),好氧PHA消耗量约为0.06mg·mg-1;35℃升温处理系统的厌氧PHA合成量约为0.11mg·mg-1,好氧PHA消耗量约为0.12mg·mg-1.当所有处理水温恢复到20℃运行后,升温处理的反应器内厌氧PHA合成量和好氧PHA消耗量都明显降低.

Using activated sludge with successful enrichment of phosphorus accumulating organisms （PAOs） ,the response of phosphorus removal characteristics in an enhanced biological phosphorus removal （EBPR） system to water temperature was measured in this study. Anaerobic phosphorus release and aerobic phosphorus uptake were clearly inhibited,and phosphorus removal rate dropped dramatically with increased water temperature in the EBPR system. The phosphorus removal rate remained at 80. 3% for the control at 20℃ all the time,while it was 0 for all 8 days of 35℃ treatment,which suggested that the EBPR system did not work at high temperature. When the water temperature of all treatments was adjusted to 20℃,the phosphorus removal rate could reach 80% after one day of recovery from 25℃ treatment,and after five days of recovery for 30℃ treatment. However,for the 35℃ treatment it could not be restored to its original status. Moreover,the capacity of anaerobic polyhydroxyalkanoate （PHA） synthesis and aerobic PHA consumption increased with the water temperature. We observed about 0. 03 mg·mg^-1 （based on sludge） anaerobic PHA synthesis,and about 0. 06 mg·mg^-1 aerobic PHA consumption in the EBPR system at 20℃ all the time,while the values were 0. 11 mg·mg^-1 and 0. 12 mg·mg^-1,respectively, for 35℃ treatment over eight days. The capacity of anaerobic PHA synthesis and aerobic PHA consumption decreased significantly in the treatments with increased water temperature even when they were returned to 20℃.