The regulatory effluent standards of live-stocking wastewater have the following maximum limits : COD＜250mg/L, SS＜150 mg/L and BOD＜80mg/L. That were announced in 1991.With regards to realistic capability of the wastewater treatment facilities existed in most of the pig-house, the COD effluent standard was readjusted to the limit of 400mg/L in 1998. In order to upgrade the process performance of the live-stocking wastewater treatment plant, the Agriculture Council and Environmental Protection Administration provided the financial support to the pig-house farmers for upgrading the treatment facilities in 2002. From a large number of the supported pig-house farms, this study selected 30 plants with different scales of wastewater treatment plant in different locations in Taiwan. Most of them have a typical three-stage treatment process to eliminate the pollutants in the live-stocking wastewater i.e. the first stage of mechanical screening unit for manure solid separation, the second stage of an aerobic digester for organic waste fermentation, and the third stage of aerobic activated sludge unit for polishing biodegradation of organic pollutants. During two investigation periods in this winter season, the statistic data of these 30 plants show the pollutant concentrations appeared with 50% of probability as the following: CODt-P50 : 8,588 mg/L ,the soluble BOD-P50 : 3,849 mg/L, and SS-P50 : 6,000 mg/L are investigated in the raw wastewater tanks of pig-house. The clarified effluent concentrations were investigated with 50% of probability as the following: COD : 486 mg/L, BOD : 81 mg/L, and SS : 114 mg/L in first survey; then, COD : 575 mg/L, BOD : 110 mg/L, and SS : 115 mg/L in the second survey.With industrious picking work of soil-manure. Separating from the raw wastewater, the final effluent could reach good quality of COD less than 250 mg/L. Therefore, the COD concentration of effluent standard is suggested to be readjusted to the more reasonable range within 400~600 mg/L according to the existed process performance of the live-stocking wastewater treatme

live-stocking wastewater,mechanical screening unit for manure solid separation,an aerobic digester for organic waste fermentation,erobic activated sludge unit for polishing biodegradation,picking work of soil-manure