基于玉米秸秆滤料的养禽冲洗废水过滤技术

过滤预处理可以有效去除养禽冲洗废水中的悬浮性固体,提高废水处理效率。为了探究玉米秸秆作为滤料的过滤规律,研究了玉米秸秆粒度、压实度和滤料装填高度对养禽冲洗废水过滤预处理的影响,建立了养禽冲洗废水过滤装置的结构模型。通过正交试验和试验验证,结果表明,当玉米秸秆粒度为1cm、压实度为1.4倍密度(74.93 kg/m~3)、滤料装填高度为50cm时滤料有最佳过滤效果,此时过滤后的养禽冲洗废水总固体(TS,TotalSolid)去除率为31.22%,挥发性固体(VS,Volatile Solid)去除率为44.51%,化学需氧量(COD,Chemical Oxygen Demand)去除率为24.07%,NH_4~+-N去除率为21.20%,达到了较好的过滤效果。对比过滤前后养禽冲洗废水厌氧发酵结果,过滤后废水厌氧发酵速率得到了明显提升,缩短了发酵周期,验证了过滤预处理对提高废水处理效率的可行性。试验结果为养殖冲洗废水过滤设备研发提供了理论依据。

Filtration technology of poultry washing wastewater based on maize stover filter media

Treatment of livestock and poultry wastewater has brought tremendous pressure to the surrounding environment, particularly to the large-scale and intensive breeding and mechanized farming. Poultry washing wastewater generally contains complex components, a large amount of solid particle sludge, and high ammonia nitrogen content, leading to single pretreatment means and high treatment costs. Alternatively, easily accessible, low-cost corn stalks can be used as filter materials to pretreat the poultry washing wastewater for high efficiency of wastewater treatment. It is an economical and effective way to treat waste with waste, thereby realizing the resource utilization and harmless treatment of poultry washing wastewater. Filtration pretreatment can also effectively remove suspended solids in aquaculture wastewater. Since the filtered solids were subjected to composting treatment, where together returning to the field for effective use of resources. Post-biochemical treatment was performed on the filtered wastewater, and further greatly reduced the processing costs of aquaculture wastewater. This study aims to explore the filtering law of corn stalk as a filter material, and the effects of corn-stalk particle size, compaction, and filling height of filter material on the filtration pretreatment of poultry-washing wastewater. A structural model was also established for the poultry-washing wastewater filtration device. The filtration characteristics of main pollutants were investigated in poultry washing wastewater under different particle sizes, filter thicknesses, and compactions, where the boundary conditions of each factor were determined. A single factor test was carried out to determine the boundary condition of parameters. The three-factor three-level orthogonal test was designed to clarify the effect of corn stalk filter on the poultry-washing wastewater. The results show that the filter material presented the best filtering performance when the particle size of corn stalk was 1cm, the compaction degree was 1.4 times density (74.93kg/m3), and the filling height of filter material was 50cm. The total solids (TS) removal rate of poultry-washing wastewater was 31.22%, the VS removal rate was 44.51%, the chemical oxygen demand (COD) removal rate was 24.07%, and the NH4+-N removal rate was 21.20%, indicating an excellent filtration performance. The anaerobic fermentation efficiency of filtered poultry-washing wastewater was much higher than before and after filtration. Under the same conditions, the anaerobic fermentation time of filtered poultry-washing wastewater was shortened by about 50%, which was of great significance to reduce the operation cost and the floor area of the project. The structure model was built for the poultry-washing wastewater filtration device using experimental parameters. The finding can provide a promising theoretical basis to develop the straw filtration equipment for aquaculture wastewaters.