Study On High Concentration Of Piggery Wastewater Treatment Process

Piggery wastewater is a kind of high concentration organic wastewater with highconcentration of pollutants, large amount of emissions, serious environmental pollution anddifficult to deal with. In this paper, the chemical flocculation-medium temperature anaerobicfermentation-SBR process were applied to experimental study on piggery wastewatertreatment, the purpose was to explore the process operating parameters, and evaluate theireffects and efficiency on piggery wastewater treatment. The results of experiment showed asfollows：Six kinds of flocculant-ferric sulfate, aluminum sulfate, aluminum chloride crystal,polymerization potassium aluminium, aluminium polychlorid and chitosan-were choosed totreatment piggery wastewater. The influent COD concentration was33560mg/L, turbidity was9931degrees, ammonia nitrogen was282mg/L, TP was123mg/L.Polymerization potassiumaluminium had higher removal rate of turbidity and NH₃-N in six kinds of flocculant, was99.70%and72.27%respectively. Chitosan had relatively higher removal rate of COD, and upto53.00%. Aluminium polychlorid had higher removal rate of TP, the removal rate was96.98%. BOD₅/COD only0.14, the effluent respectively was0.415,0.504,0.424,0.505,0.379,0.135after flocculation treatment of these six kinds of flocculant.Using principalcomponent analysis comprehensive comparison of six kinds of flocculants of piggerywastewater treatment effect, polymerization potassium aluminium was the better flocculationagent for piggery wastewater treatment. The effluent turbidity was30degrees, CODconcentration was17736mg/L, NH₃-N was78mg/L, TP was4.0mg/L.The piggery wastewater after polymerization potassium aluminium flocculationtreatment with COD17736mg/L,NH₃-N78mg/L, TP4.0mg/L, then after24hours anaerobicfermentation treatment at the temperature35℃, the effluent COD concentration was2769mg/L, removal rate reached84.39%,NH₃-N was80.0mg/L, TP was11.76mg/L.Measured gas production was1.125liters per liter wastewater. SBR process was applied to treatment piggery wastewater after medium temperatureanaerobic fermentation treatment. In the SBR processing stage, aeration time, sedimentationtime, sludge concentration, sludge load had significant impacts on the removal rate of COD,NH₃-N and TP.SBR process operation parameters: water time was one hour, aeration timewas eigth hours（Water along with aeration）, precipitation time was one hour, idle time wastwo hours, sludge concentration was4785mg/L, Sludge load was2.31kgCOD/（kgMLSS·d）.The influent COD concentration was2769mg/L, ammonia nitrogen was80.0mg/L, TP was11.76mg/L, the effluent COD concentration was346mg/L, NH₃-N was12mg/L; TP was4.6mg/L, the removal rate of COD, NH₃-N,TP respectively was87.5%,85%,60.9%;the value ofSV was29%, SVI was61, SS was41mg/L, the reactor had good capacity of resistance toimpact load.The total COD removal rate reached98.97%, NH₃-N removal rate reached95.74%,removal rate of TP96.26%in the whole treatment process. The influent COD concentrationwas33560mg/L, ammonia nitrogen was282mg/L, TP was123mg/L, the effluent CODconcentration was346mg/L, NH₃-N was12mg/L; TP was4.6mg/L, reach to therequirements of livestock and poultry breeding wastewater discharge standard. In this paper,the research results showed that the chemical flocculation-medium temperature anaerobicfermentation-SBR process had good treatment effect on piggery wastewater.