Technology Research Of Solid-Liquid Separation Of The Acidificated Cow Muck

The development of livestock and poultry industry meets the life needs of people to meat, milk etc but poses a serious environmental pollution. In the livestock and poultry feces, cow muck accounted for68%,so it is pollution sources as well as very good organic fertilizer source and fuel. The moisture content of fresh cow muck around for65%or so, and content of crude fiber is greater, accounted for nearly40%of dry matter, if using fresh cow muck to compost, moisture content is greater, go it is against plant growth; If using fresh cow muck on anaerobic fermentation, fiber of it is difficult to degradation, so the fermentation equipment utilization rate is low, and easy to produce with slag, affecting the effect of gas production. It is very necessary to use solid-liquid separator to dewater cow muck.But the solid-liquid separator is mostly generic foreign advanced equipment or produced by the actual production experience, so their work efficiency is not high. It doesn’t grasp the equipment work principle. As a result, improving the solid-liquid separator is urgently to be solved by theoretical analysis and research. At the same time, the separated and diluted cow muck can miniaturize the grain in the separated liquid, shorten the hydraulic retention time and improve the equipment utilization.This paper, based on the previous studies, has done a more systematic and detailed analysis about the working principle and structure parameters of the screw axis of the manure solid-liquid separator and the manure solid-liquid separation pretreated technology after acidification. The study and research include the following:(1) The improvement of the screw axis of the manure solid-liquid separatorScrew-type solid-liquid separator is a new solid-liquid separation equipment reference to foreign technology in domestic production. It has a simple structure, low energy consumption, good separation, small footprint, etc., with a wide range of applications in agricultural organic waste separation. And most of solid-liquid separator are equal to the shaft diameter the pitch, while the moisture content of material in the solid-liquid separation process is constant changing, so the equipment can’t adapt to the characteristics of the material affecting the efficiency of solid-liquid separator. According to the separated materials at different stages of the friction characteristics and the volume compression research, drawing the spiral angle adapting to the material properties and screw shaft diameter parameters, designing the adjustable variable diameter, pitch and spiral angle of the rotation shaft, thereby providing a basis to the improvement of screw press solid-liquid separator. (2) The manure solid-liquid separation technology research after acidificationUsed total solid content (TS) of separated solids^separation efficiency、solid removal ratio as reference index but the total solid content (TS) of separated solids as main reference index and water food ratio、bar interval、screw speed as influence factors, through the response surface method (RSM) of Design-Expert6.0.1software to do the five level three factors quadratic orthogonal rotating combination research design to draw the interaction regression equations and change curves of different factors and levels,then inspect the equation, optimize the model as well as research the water food ratio、bar interval、screw speed on the influence regulation of solid-liquid separation effect. At the same time, compareing the changes of methane production of acidificated and unacidificated pretreatmented caw muck,draw the conclusion that acidification before the solid-liquid separation then fermentation can improve the efficiency of the methane production.