炼油废水的物化预处理工艺研究

Study on Physicochemical Pretreatment Process for Oil Refinery Wastewater

对炼油废水的物化预处理工艺进行了研究,比较了分别投加5种不同混凝剂的混凝沉淀效果。结果表明:SHY-Ⅲ型混凝剂与PAM配合投加时对浊度和COD的去除效果最好;投加电解质CaCl2后破乳效果显著;混凝剂和CaCl2的投加量对混凝效果均有影响。对混凝沉淀出水采用气浮或超滤工艺进行处理可进一步去除废水中的乳化油,但对溶解性COD的去除作用微弱。经过物化预处理后,废水中大量有毒、难降解的有机物被去除,可生化性大大提高。

The physicochemical pretreatment process for oil refinery wastewater was studied. Coagulation and sedimentation effect of five coagulants were compared. The results show that SHY - Ⅲ inorganic coagulant combined with PAM has the best effect in removing turbidity and COD. The demulsification effect is apparent after addition of CaCl2. The concentration of SHY - Ⅲ and CaCl2 has an influence on coagulation. Flotation or ultrafihration can further remove the emulsible oil after coagulation and sedimentation, however, it has little effect on removing the dissolved COD. Pretreated by physicochemical process, a large number of noxious and refractory organic compounds are removed, which improves the biodegradability of oil refinery wastewater.