石灰软化-絮凝法处理地下水硬度动态中试试验研究

摘要

Lime softening-flocculation process was used to treat hardness of groundwater of a water supply plant in southern China,a dynamic pilot-scale test equipped with integrated device on the treatment of the said kind of water was carried out with the aim of investigating the operation effect of lime-softening process and exploring the influence of lime and PAC dosage on water treatment effect.The results of the test showed that,when the dosage of Ca(OH)2 and PAC were 299.1-361.3 and 43.6-48.7mg/L respectively,a satisfying treatment effect could be obtained.The total hardness (calculated by CaCO3) and total alkalinity decreased to 110 and 80 mg/L respectively,which met the requirement of GB 5749-2006 Standards for drinking water quality.According to the analysis from aspects of infrastructure,equipment investment and running cost,it could be found that,the water producing cost of lime softening process was 0.457 yuan/t lower than that of the ion exchange process.%采用石灰软化-絮凝法处理华南地区某水厂地下水硬度.动态中试试验采用一体化处理装置,考察石灰软化工艺运行效果,并进一步探索石灰投加量和PAC投加量对试验效果的影响.试验结果表明,Ca(OH)2投加量为299.1 ～ 361.3 mg/L、PAC投加量为43.6～48.7 mg/L,处理效果较佳.处理后总硬度(以CaCO3计)降到110mg/L,总碱度(非碳酸盐碱度)降到80 mg/L,符合GB 5749-2006《生活饮用水卫生标准》要求.基于基础设施、设备投资和运行成本的分析表明,石灰软化工艺较离子交换工艺的制水成本减少0.457元/t.