混凝剂在海水淡化预处理中的选择

Selection of Coagulants in Desalination Pretreatment

根据实验结果,在不需要调节海水pH值的情况下,比较适合采用铝盐做絮凝剂,但铝盐会有残留痕量铝离子对膜有堵塞的潜在影响;铁盐没有痕量离子对RO影响的情况,但需要调节pH值,才能满足絮凝效果的要求,但硫酸的运输和储存会带来严重的影响。使用铝盐作为絮凝剂作预处理的海淡设备3 a运行实际数据表明,通过控制铝盐的使用量和运行方式,痕量铝离子并没有对膜运行产生非常显著的影响。铁盐和铝盐的选择和使用应根据设备应用的实际情况,对于硫酸运输困难的地区,应首先选择铝盐作为絮凝剂,减少运输和保障安全。

According to the experimental results,it is suitable to use aluminum salt as coagulant without the need to adjust seawater pH value,but aluminum salt may have residual trace aluminum ions on membrane blockage;Iron salt has no trace ion effect on RO,but pH value is adjusted to meet the requirements of coagulant effect.but the transport and storage of sulfuric acid will have serious effects.According to the actual data of 3-year operation of seawater desalination pretreatment equipment using aluminum salt as coagulant,it showed that the trace aluminum ions have no significant effect on the membrane operation through controlling aluminum usage and operation style.The selection and use of iron salts and aluminum salts shall be based on the actual situation of the equipment application.For the areas with sulfuric acid transport difficulties,aluminum salts shall be first selected as the coagulant to reduce the transportation and safety.