氮、磷对藻类生长及污水净化的影响

室内模拟氧化槽比较,研究污水中不同含量的磷及氮、磷比例对藻类生长及污水净化的影响。原污水中含氮量均为20mg/L,磷的含量分别为1.25 2.50 5.0 10mg/L,结果发现原污水中的N/P为20/2.5时,藻类的净生产量最高,污水净化效果最好。

Influences of Phosphorus on Algae Growth and Sewage Purification

An experiment on the influences of phosphorus in raw sewage on algae growth and sewage purification was carried out in modeling stabilization pond system in laboratory. Results indicate that when TN concentrations are all kept at 20mg/L in raw sewage and TP changed from 1.25, 2.50, 5.00 to 10.00mg/L, the removal rate of TN, B0D5 and LAS are decreased with increasing TP concentration, but the removal rate of TP presents an opposite tendency. The ratio of N/P=20/2.50mg/L is the better concentration and ratio for swage purification than others. This result is correlated with the net oxygen production of algae. There are different species compositions of algae existed in different N/P systems. When the ratio of N/P is changed form 20/1.25, 20/2.5, 20/5 to 20/10mg/L, the percentage of green algae is decreased with increasing TP concentration, but blue algae presents an opposite tendency which may cause high levels of algae density, biomass, oxygen consumption, pH value and rate of purification.