Treatments of chemical mechanical polishing (CMP) wastewater from semiconductor fabrication of photovoltaic wafers by chemical physical and electrochemical methods are investigated. The CMP wastewater, as obtained from a Silicon Technology Development Unit (UDTS) in Algeria, was characterized by high mineral pollution content, high turbidity (NTU) and a chemical oxygen demand (COD). Due to these characteristics, treatment of the CMP wastewater by either traditional method was inadequate. In the present work, chemical physical methods and electrocoagulation were employed to tackle the turbidity and COD problems. Experimental tests were conducted to assess the effectiveness of the treatment and to identify the optimum operating conditions. Test results clearly demonstrated the complementary advantages of the two methods.
Keywords: CMP wastewater; silicon wafer; semiconductor fabrication; photovoltaic industry; chemical physical ; electrocoagulation; treatment; environment;
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