浓缩倍率10以上循环水除硅技术的研究及应用  

Research and application of silicon removal technology for circulating water with concentration ratio above 10

作　　者：申军锋 沈健 SHEN Junfeng;SHEN Jian(Huizhou Shenzhen Energy Fengda Power Co.,Ltd,Huizhou 516025,China;Shenzhen Energy Group,Shenzhen 518000,China)

机构地区：[1]惠州深能源丰达电力有限公司,广东惠州516025 [2]深圳能源集团,广东深圳518000

出　　处：《电力科技与环保》2023年第3期221-226,共6页Electric Power Technology and Environmental Protection

基　　金：科技支撑深圳碳中和目标实现对策研究(深科技创新[2021]279号)。

摘　　要：为进一步提高循环水浓缩倍率,解决部分循环水在高倍率下时SiO_(2)先达到结垢极限,浓缩倍率提高受限问题。本文在实验室向平行烧杯水样中,分别手动添加1 g MgO,2 g MgO,1 g MgO+PAC,2 g MgO+PAC+PAM四种单镁剂进行除硅试验,以及分别添加1%PAC 0.5 mL,1%PAC 1.0 mL,1%PAC 0.5 mL+5‰PAM 0.5 mL,1%PAC 1.0 mL+5‰PAM 1.0 mL药剂的组合絮凝沉降试验,确定最佳处理药剂组合为MgO+氢氧化钙(pH=12)+1%PAC 0.5 mL+5‰PAM 0.5 mL。在电厂已建具有絮凝、沉淀、过滤的工业废水系统中进行了实际应用,对最佳处理药剂组合进行检验。结果表明,实验室中“氧化镁+氢氧化钙”的除硅组合药剂是最佳组合,最高除硅率可达92.1%。在2×600 MW燃煤机组现场试验中,最佳药剂组合的应用,可实现实际废水处理量为100 t/h左右,除硅率稳定在85%左右,产水硬度降低,回用循环水系统后浓缩倍率从原9倍提升至11~12倍,效果明显。循环水投加“氧化镁+氢氧化钙”组合药剂,然后絮凝沉淀处理后回用,成功达到循环水除硅、将浓缩倍率上限提升2~3倍、减少排水量以实现全厂水量再平衡的目的,具有经济性和示范性。In order to further improve the concentration ratio of circulating water,the problem that Some circulating water reaches the scaling limit of SiO_(2) first at high multiplier,and the increase of concentration multiplier is limited has been solved.In this paper,four kinds of single magnesium agents,1 g MgO,2 g MgO,1 g MgO+PAC,2 g MgO+PAC+PAM,were manually added to the parallel beaker water samples in the laboratory to remove silicon,and 1%PAC 0.5 mL,1%PAC 1.0 mL,1%PAC 0.5 mL+5‰PAM 0.5 mL,1%PAC 1.0 mL+5‰PAM 1.0 mL were added to the combined flocculation sedimentation test.The optimum treatment agent combination was MgO+calcium hydroxide(pH=12)+1%PAC 0.5 mL+5‰PAM 0.5 mL.It has been applied in the industrial wastewater system with flocculation,sedimentation and filtration in the power plant,and the best combination of treatment agents is tested.The results showed that the combination of magnesium oxide and calcium hydroxide in the laboratory was the best combination,and the highest silicon removal rate could reach 92.1%.In the field test of 2×600 MW coal-fired units,the application of the best reagent combination can achieve the actual wastewater treatment capacity of about 100 t/h,the silicon removal rate is stable at about 85%,the hardness of the produced water is reduced,and the concentration ratio is increased from 9 times to 11-12 times after reuse of the circulating water system.The circulating water is added with a combination of'magnesium oxide+calcium hydroxide',and then reused after flocculation and sedimentation treatment.It successfully achieves the purpose of removing silicon from circulating water,increasing the upper limit of concentration ratio by 2-3 times,and reducing the amount of drainage to achieve the purpose of rebalancing the water volume of the whole plant.It realized the water re-balancing of the whole plant,which has economical and demonstrative.

关 键 词：废水零排放 除硅 氢氧化钙 镁剂除硅 回收利用 

分 类 号：X703.1[环境科学与工程—环境工程]