石灰絮凝法应对季节性低浊高锰原水的实践

Practice of Lime Flocculation for Seasonal Low Turbidity and High Manganese Raw Water

在夏季高温期间,水库底层易出现低浊高锰原水。常用的高锰酸钾预氧化除锰方法,在停留时间较短的水厂除锰效果不佳,影响供水安全。深圳某水厂采用石灰絮凝法应对此问题,制定了优化石灰投加量、调整排泥频率等一系列措施,以优化絮凝反应条件,降低出水锰含量。采取上述措施后,平均滤池出水锰含量为0.01 mg/L,稳定低于国家标准,其他水质指标均符合《生活饮用水卫生标准》(GB 5749—2022)。可见,该水厂应对季节性低浊高锰原水水质的措施科学可行且成效显著,可为同行提供借鉴。

During the summer high temperature period,low turbidity and high manganese raw water is easy to appear in the lower layer of reservoir.The commonly used potassium permanganate preoxidation process for removing manganese is not effective in waterworks with short residence time,which affects the safety of water supply.Aiming at this problem,a waterworks in Shenzhen adopts lime flocculation process,establishes a series of measures such as optimizing lime dosing quantity and adjusting discharge frequency to optimize flocculation reaction conditions and reduce the effluent manganese.After adopting the above measures,the average manganese content of filter effluent was 0.01 mg/L,which is lower than the national standard,and other water quality indicators are in line with the Standards for Drinking Water Quality(GB 5749-2022).The result shows that the measures taken by the waterworks to deal with seasonal low turbidity and high manganese raw water quality are scientific,feasible and effective,which can provide technical reference for counterparts.