黄河水沉淀后水质对滴灌灌水器堵塞的影响

Effect of water quality of Yellow River after sedimentation on emitter clogging in the drip irrigation system

利用2013年5月—10月和2014年7月—11月的实测数据,分析了乌海市不同功能的三个典型沉淀池(如意湖、林业湖和朝阳湖)的浊度、细菌总数、叶绿素a、总氮、总磷五项水质指标的沉淀、过滤效率,利用灌水器堵塞野外调查数据并结合堵塞物电镜扫描图片,探讨了黄河水经过平流沉淀+网式过滤组合模式处理后仍会造成灌水器堵塞的原因。结果表明:各沉淀池浊度的沉淀和过滤效率均较高,其中如意湖的沉淀效率最高,平均去除率为63%;2013年朝阳湖的过滤效率最高,为60.53%,各沉淀池水质指标的过滤效果普遍较差。黄河水经沉淀过滤后仍会造成灌水器堵塞,其主要原因与细小颗粒物和微生物形成的絮状结构有关,建议对原有沉淀、过滤措施提出改进,经一、二级沉淀后在泵房内改用叠片式砂过滤器。

The sedimentation and filtration efficiencies of water-quality indexes including turbidity,the total amount of bacteria,chlorophyll A,total nitrogen,total phosphorus were analyzed in this study utilizing the monthly monitoring data from May to October in 2013 and from July to November in 2014 for the three typical sedimentation tanks in Ruyi lake,Linye lake and Chaoyang lake in Wuhai city. Through combined investigations in field and by scanning electron microscope on blockage,the cause for emitter clogging was discussed after treated with Yellow River water undergone horizontal flow sedimentation and net type filter. The results showed that the sedimentation and filtration efficiencies of turbidity for each tank were relatively high. The sedimentation efficiency of turbidity in Ruyi Lake was the highest and its average rate was 63%. The filtration efficiency of turbidity in Chaoyang Lake in 2013 was higher than other tanks,and its rate was 60. 53%. The filtration effect of water-quality index was generally inferior for each tank. Flocculent structure that was formed by small particles and microorganisms was the main cause for emitter clogging by the Yellow River water undergone sedimentation and filtration. Moreover,improvement scheme was thereby proposed for the original sedimentation and filtration measures and laminated sand filter in pump house was employed after the one and two-stage sedimentation.