No abstract

This experiment explores to pre ozone used for wheat straw pulp hypochlorite bleaching wastewater treatment of optimum oxidation time, initial pH of Fenton reaction water, H 2 O 2 /FeSO 4 dosing ratio, reaction time on Fenton method depth treatment effect of bleaching effluent. The bleaching wastewater is pretreated with the ozone concentration 2.9mg/l. The experimental results show that the best pretreatment time of ozone is 30min. The removal rates of CODcr, TOCcr and chroma were 53.9%, 82.8% and 68% respectively with ozone pretreatment. The ozone oxidation process has a good effect on the removal of organic substances in wastewater. Treatment of straw pulp hypochlorite bleaching wastewater by Fenton reagent, the experimental results show that CODcr removal rate of wastewater is about 74%, the chroma is above 87.5%, and the supernatant is colorless under the initial ph5.6, H 2 O 2 of 1ml, n (H 2 O 2): n (Fe 2+)=4, FeSO 4 dosage 2ml, reaction temperature 20°C, reaction time 40min, 0.1%PAM.

No abstract

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.