摘要
高盐含磷废水具有盐含量高、污染物成分复杂和生物处理难等特点。生产鸟粪石后的浓海水因添加过量的Na_(2)HPO_(4)及NH_(4)HCO_(3)等诱导剂和稀释剂,其上清液中会有PO_(4)^(3-)-P残留。针对其上清液磷含量超标的问题,使用化学沉淀法进行除磷实验。选用聚合氯化铝(PAC)、FeCl_(3)、Ca(OH)_(2)、聚丙烯酰胺(PAM)作为实验药剂,研究了反应时间、单一药剂添加量和药剂复配等因素对除磷效果的影响,筛选出2种满足出水磷含量要求(0.5 mg/L)的工艺条件。方案1:添加n(Ca)/n(P)=4.5的Ca(OH)_(2),处理后溶液PO_(4)^(3-)-P含量为0.2 mg/L;方案2:添加n(Al)∶n(P)=0.5的PAC+n(Ca)/n(P)=4.0的Ca(OH)_(2)+0.5 g/L PAM,处理后溶液PO_(4)^(3-)-P含量为0.4 mg/L。综合分析,方案1操作方便,方案2有助于固液分离,二者均可以用作废水处理方案,研究结果为高盐含磷废水处理提供了一个切实可行的思路。
High-salinity phosphate-containing wastewater has the characteristics of high salt content,complex pollutant composition and is difficult to be treated by the biological method.The supernatant will contain some PO_(4)^(3-)-P after struvite production by adding excessive inducers and diluents such as Na_(2)HPO_(4) and NH_(4)HCO_(3) to seawater.A chemical precipitation method was applied for excessive phosphate removal.In our experiment,poly-aluminium chloride(PAC),FeCl_(3),Ca(OH)_(2) and polyacrylamide(PAM)were selected as experimental chemical reagents.The effect of reaction time,the additive amount of a single chemical reagent and a combination of chemical reagents on the phosphate removal effect were studied.Finally,two strategies were selected,which could make the phosphate content in the effluent meet the emission standard.Strategy 1:adding Ca(OH)_(2) with a molar ratio of Ca:P of 4.5 made the PO_(4)^(3-)-P content decrease to 0.2 mg/L.Strategy 2:adding Ca(OH)_(2) with a molar ratio of Ca:P of 4.0,PAC with a molar ratio of Al:P of 0.5,and PAM with a concentration of 0.5 g/L made PO_(4)^(3-)-P content decrease to 0.4 mg/L.Strategy 1 was easy to operate while strategy 2 was helpful for solid-liquid separation.Both of them can be used for the treatment of high-salinity phosphate-containing wastewater.The results provide a practical idea for the treatment of high-salinity phosphate-containing wastewater in the future.
作者
李晴晴
杨彦
席欢
郭风
张建峰
阮仕平
LI Qing-qing;YANG Yan;XI Huan;GUO Feng;ZHANG Jian-feng;RUAN Shi-ping(Institute of Mechanics and Materials,Hohai University,Nanjing 210098,China;Nanjing Hydraulic Research Institute,Nanjing 210029,China;Jiangsu Engineering Research Center on Utilization of Alternative Water Resources,Nanjing 210000,China)
出处
《环境工程》
CAS
CSCD
北大核心
2022年第5期31-36,共6页
Environmental Engineering
基金
国家重点研发计划项目(2018YFC0408003)。
关键词
高盐含磷废水
化学沉淀法
铁铝钙盐
絮凝剂
复配
high-salinity phosphate-containing wastewater
chemical precipitation method
iron aluminum calcium salt
flocculant
compound
