Research on The Ozone and Electromagnetic Cotreatment Technology of Papermaking Wastewater

摘要

In this paper, ozone-electromagnetic technique was used to treat papermaking wastewater. It was found that the value of COD, BOD, TOC, SS, AN(Ammonia Nitrogen) and CHR(Chromaticity) of wastewater treated with the specially designed ozone sewage treatment unit decreased from 2660mg/L, 1165mg/L, 1962mg/L, 707g/L, 112mg/L and 120 times to 782mg/L, 118mg/L, 684mg/L, 112g/L, 16mg/L and 50 times respectively. The values were reduced by 71%, 90%, 65%, 84%, 86% and 58% respectively. The EC(Electrical Conductivity) increased by 2.1% slightly from 2800Ω~(-1)·cm~(-1) to 2860Ω~(-1)·cm~(-1). Subsequently, the treatment of papermaking wastewater was continued with graphite electromagnetic device. The results shown that the optimal treatment conditions were as follows: voltage 9.2 V, current 1.72 A, number of graphite plates in series 10, plate distance 3.24 mm, treatment time 25 min. Under these conditions, the value of COD, TOC, BOD, SS, AN, EC and CHR of papermaking wastewater can be reduced to 89mg/L, 71mg/L, 53mg/L, 33g/L, 8mg/L, 68Ω~(-1)·cm~(-1) and 12times, the removal rates are 97%, 94%, 97%, 95%, 93%, 98%, 90% respectively. By using the ozone system and electromagnetic equipment, the paper-making wastewater has achieved good results, which creates favorable conditions for wastewater reuse and zero discharge.