• Journal of Korean Society of Environmental Engineers
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• v.38 no.9
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• pp.469-475
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• 2016

The study is the result of an practical operation analysis for the full scale fishery product wastewater treatment plant with immersed MBR (iMBR) process. Since fishery product industries show a wide range of wastewater generation by the season, design and operation of the equalization basin are very important factor. The aeration system for the equalization basin mixing can save the chemical consumption for followed system through the restriction of acid fermentation. The concentrations of wastewater primary DAF process treated were BOD 2,291 mg/L, $COD_{Mn}$ 530 mg/L, SS 256.8 mg/L, T-N 38 mg/L, T-P 13.5 mg/L respectively. It was considered that iMBR is the most efficient biological process for high salinity content wastewater since It is irrelevant to the capability of the sludge precipitation. SADp and SADm were 0.31, $26.5m^3/hr{\cdot}m^3$ respectively. In iMBR process, the critical F/M ratio was derived at 0.08~0.10 gBOD/gMLSS by analysing the correlations between MLSS, normalized TMP and temperature. The effluent concentrations were BOD 1.8 mg/L, $COD_{Mn}$ 12.4 mg/L, SS 1.0 mg/L, T-N 7.85 mg/L, T-P 0.1 mg/L and removal efficiencies were 99.9%, 97.6%, 96.3%, 95.7%, 97.8% respectively.

• Membrane Journal
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• v.22 no.6
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• pp.461-469
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• 2012

This study was carried out to find the optimum chemical cleaning (CIP) conditions for ceramic microfiltration membrane process of Y drinking water treatment plant. B train consists of coagulation as pretreatment process with membrane was chemically cleaned 9 times more than that of A train with ozonation and coagulation. The frequent CIP of B train was due to improper CIP method suggested by membrane manufacture as well as different membrane fouling between A and B train resulting from the different pretreatment processes. That is, recovery rate of CIP was overestimated because the rate was calculated based on normalized trans membrane pressure (TMP) rather than normalized permeability. And also, iron oxide fouling was ineffectively removed by citric acid. By using a mixture of 1% citric acid and 0.1 N sulfuric acid as reagent for acid CIP step, the recovery rate of CIP was the highest while CIP efficiency by 0.1 N sulfuric acid was the lowest. When sulfuric acid concentration increased from 0.1 N to 0.3 N in mixture, total recovery rate of CIP was not increased due to the decreased CIP efficiency in alkali CIP step by 0.3% NaOCl although its rate in acid CIP step was increased. It was proved through the experiment result of CIP sequence changes that an acid followed by alkali CIP was more effective than that of the reverse method.