自来水厂含氯水对供水泵空化特性的影响

Influence of Water Containing Chlorine on Pump Cavitation Behavier in Water Supply Plants

为了解决自来水厂含氯水对供水泵叶轮进口区域造成的空蚀破坏问题 ,用自行研制的水初生空化压力和充分空化压力测量装置 ,对不同氯质量浓度的水样进行了试验研究。结果表明 ,在室温 2 0℃ ,氯质量浓度为 0 .5～ 1.3mg.L-1的条件下 ,自来水样的初生空化压头为 5 .71～ 6 .4 1m ,充分空化压头为 0 .6 0～ 0 .6 8m,饱和汽化压头为 0 .2 4 m,故 Δ值为 5 .4 7～ 6 .17mm;空化压力值和氯质量浓度近于线形关系。若将供水泵的吸上高度较抽送清水时降低 Δ/2 。

For solving the question of cavitation damage of impeller inlet, induced by water containing chlorine, in pumps in water supply plants, a measurement device used to measure the incipient cavitation pressure was developed and the full developed cavitation pressure of water samples with different chlorine concentration was analysed. The experiment result indicated that the incipient cavitation pressure and full developed cavitation pressure, with 20 ℃ room temperature and 0 5～1 3 mg/L chlorine concentration in water samples, were 5 71～ 6 41 m and 0 60～ 0 68 m respectively. With Pd=0 24, therefore, Δ =5 47～ 6 17 m. The result also indicated that the value of cavitation pressure was nearly linear to the quality concentration of chlorine. Accordingly, by reducing the suction height of pumps with the value of Δ /2, compared with the condition of pumping pure water, the pump cavitation status will be improved greatly.