Inorganic Chemicals Industry ›› 2025, Vol. 57 ›› Issue (2): 68-75.doi: 10.19964/j.issn.1006-4990.2024-0162

• Research & Development • Previous Articles     Next Articles

Study on performance and mechanism of titanium salt coagulant for treatment of oily wastewater

HUANG Tianyin1(), SUN Ling1, ZHAO Qinzheng1, CHEN Xin1, SONG Xiaojie2, WU Bingdang1()   

  1. 1.School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009,China
    2.SINOPEC Yangzi Petrochemical Co. ,Ltd. ,Nanjing 210048,China
  • Received:2024-03-21 Online:2025-02-10 Published:2025-02-20
  • Contact: WU Bingdang E-mail:huangtianyin111@163.com;wubingdang@usts.edu.cn

Abstract:

Emulsified oil is more difficult to be removed because of its small particle size and difficult to be agglomerated.Coagulation is widely used in the treatment of emulsified oil.However,the traditional iron and aluminum salt coagulants produce small flocs and have slow generation rate,which make it difficult to realize the rapid separation of oil and water,resulting in poor deep oil removal effect.The new titanium salt coagulant is expected to solve the application problem of iron aluminum salt coagulant due to its outstanding coagulation performance.In this paper,a new type of titanium gel coagulant(TXC) for the treatment of oily wastewater was evaluated by using four kinds of simulated emulsified oil water,such as lubricating oil,soybean oil,petroleum ether and diesel oil,and choosing polyferric sulfate(PFS) and polyaluminum chloride(PAC) as the control.The results showed that TXC had better coagulation effect on emulsified oil wastewater than PFS and PAC.Taking lubricating oil as an example,in the initial pH range of 3~11,dosage of 1~60 mg/L and oil content of 500~2 000 mg/L,the oil removal rate of TXC was up to 91.526%.It was better than PFS and PAC.The turbidity of the oil-bearing wastewater after TXC coagulation was less than 1 NTU,and the particle size of the oil was the smallest,which indicated that TXC had the application potential of deep oil removal.The results of floc characterization showed that TXC mainly removed oil by net sweeping,and because of its large floc size,it was easier to remove small particle size oil droplets.The research results provided new ideas for the treatment of oily wastewater,especially emulsified oil wastewater.

Key words: emulsified oil, coagulation, oil removal, particle size, titanium coagulant

CLC Number: