果园种植面源污染电混凝去除的关键设计及PAM强化

摘要:

针对果园种植面源污染电混凝去除尚不明确的问题,以果园种植面源常规污染物为研究对象,考察电混凝关键设计,分析pH和电导率的影响,并探讨聚丙烯酰胺(PAM)的强化条件。结果表明：电压为10 V(2.5 mA/cm²),电极间距为1 cm时,电混凝处理性能达到最佳,其中总悬浮颗粒物(TSS)、硝氮(NO3^ˉ-N)、氨氮(NH3-N)、总氮(TN)和总磷(TP)的去除率分别为70.6%、30.4%、78.4%、23.7%和92.1%；酸性(pH=5)和碱性(pH=9)条件均不利于这些污染物去除；电导率的增大有利于NH3-N去除,但不利于其它污染物去除；当PAM投加量为0.5 mg/L、沉淀时间为5 min时,其强化效果最明显,对TSS、NH3-N和TP去除均有强化,去除率增幅分别为39.1%、10.3%和7.5%,但对NO3^ˉ-N和TN去除有一定的抑制；研究结果为电混凝预处理果园种植面源污染提供理论和数据参考。

Abstract:

Aiming at the unclear problem of electrocoagulation removal of non-point source pollution in orchard planting, taking the conventional non-point source pollutants in orchard planting as the research object, the key designs of electrocoagulation were investigated, the effects of pH and conductivity were analyzed, and the strengthening conditions of polyacrylamide (PAM) were discussed. The results showed that electrocoagulation treatment achieved the best removal effect when the voltage was 10 V(2.5 mA/cm_²) and the electrode spacing was 1 cm. The removal rates of total suspended solids (TSS), nitrate (NO_3^ˉ-N), ammonia (NH₃-N), total nitrogen (TN) and total phosphorus (TP) reached 70.6%, 30.4%, 78.4%, 23.7% and 92.1% respectively. Acidic (pH=5) and alkaline (pH=9) conditions were not conducive to the removal of these pollutants. The increase of conductivity improved the removal of ammonia, but weakened the removal effect of other pollutants. When the dosage of PAM was 0.5 mg/L and the precipitation time was 5 min, PAM enhanced the removal of TSS, NH₃-N and TP to the best extent, increasing by 39.1%, 10.3% and 7.5% respectively, but it inhibited the removal of NO_3^ˉ-N and TN to a certain extent. The results provided theoretical and data reference for electrocoagulation treatment of orchard planting non-point source pollution.