钙法化学混凝工艺处理海底钢管酸洗废水  

Treatment of acid-washing wastewater from submarine steel pipeline cleaning by calcium precipitation

作　　者：赵利[1] 李长春[1] 相政乐[1] 贾振[1] 王铭浩[1] 

机构地区：[1]中海油能源发展股份有限公司管道工程分公司,天津300452

出　　处：《工业用水与废水》2013年第5期35-38,共4页Industrial Water & Wastewater

摘　　要：针对海底钢管酸洗废水成分复杂、酸度高、含磷量高的特点,采用钙法化学混凝工艺对其进行处理。通过单因素试验考察了体系pH值、反应时间、生石灰投量和静置时间等因素对除磷效果的影响。试验结果表明,酸洗废水磷酸盐的质量浓度为124.3 mg/L时,在生石灰的投加量是理论投加量的2.5倍,反应体系pH值大于或等于11.0,25℃下恒温搅拌反应30 min、静置30 min的条件下,出水磷酸盐的质量浓度(以磷计)降至1.0 mg/L,达到了GB 18918—2002《城镇污水处理厂污染物排放标准》中一级B排放标准的要求。pH值是钙法化学混凝除磷的控制性因素,用生石灰做混凝剂可以补充溶液的碱度,进而减少了氢氧化钠的用量,节约了处理成本。Using calcium precipitation process to treat acid-washing wastewater from submarine steel pipeline cleaning which was characterized by complicated component, high acidity and high phosphorus concen- tration. The effects of pH value, reaction time, quick lime dosage, static placing time and some other factors on phosphorus removal were investigated through a single-factor test. The results of the test showed that, when the mass concentration of phosphate in the acid-washing wastewater was 124.3 mg/L, the effluent phosphate mass concentration （calculated by phosphorus） decreased to 1.0 mg/L under the condition that the dosage of quick lime was 2.5 times larger than the theoretical dosage, the pH value of the system was not lower than 11.0, the stirring and static placing time were both 30 min at a stable temperature of 25 ℃, which indicated that the effluent water met the specification for grade 1 class B in GB 18918--2002 Discharge standard of pollutants for municipal wastewater treatment plant. As pH value was a controlling factor for phosphorus removal by calcium precipitation process, using quick lime as the coagulant could increase solution alkalinity, reduce NaOH dosage, and save treatment cost at the same time.

关 键 词：钙法 酸洗废水 除磷 羟基磷酸钙 

分 类 号：X703.1[环境科学与工程—环境工程]