Thermal Press Filtration Mechanism And Experimental Research Of City Surplus Activated Sludge

With the accelerated urbanization, the increased population density, and the increasing emissions of urban sewage, urban sewage treatment plant has to deal with the significantly increased sludge. In order to avoid secondary pollution, scientific and effective use of waste, sludge disposal has become an important topic to facing. And the future direction will be sound and resources sludge disposal. However, due to a colloid-like sludge, and water affinity, using the traditional methods of mechanical dewatering filter is generally lead moisture content of dewatered sludge reach to 75% or more. Then usually can not directly use such high moisture content, so most of the existing sewage treatment plant dewatered sludge are Sinatra's landfill, it will not only pollute the environment, but also make the original available resources wasted.If you want to getting harmless and resources of sludge, the premise is that senior cadres of the degree of sludge dewatering.This project is from Suzhou environmental project, which is "The research about key technologies to disposal city domestic sewage sludge use harmless and utilization way" (Item number: N3117925). It carries out "Thermal Press Filtration Mechanism and Experimental Research of City Surplus Activated Sludge" topics. This study includes the following:Chapter One: First of all, it holds out sources and research issues. Then, explains the technology and research status significance of the domestic hot water solution by thermal press filtration, and establishes the main research topics.Chapter Two: Thermal press filtration theory. Does the theory research for thermal press filtration, and theoretically analyse the influence of pressure and temperature on seepage in the process of thermal press,models classical filtration equation, and corrects factors incorporated into the classical filtration equation. It helps laying a good foundation for the order.Chapter Three: Construction of Activated Sludge Heat equation. To percolation theory, mathematical model was constructed hot flow. And the equation of the traditional filter based on the combination of activated sludge senior cadres of the degree of dehydration required to build the hot sludge filter equation.Chapter Four: Test plan and Test design. To further verify the mechanism and the activity of sludge build hot filtration equation and find the optimal operation condition, according to senior cadres of the degree of hot sludge filtration requirements, this paper researched on a set of hot filtration activated sludge system test process, and has done more in-depth research on test methods, established a pilot program.Chapter Five: Test Research.. This paper analysed the basic principle of the thermal press filtration through the experiment comparasion. Experimental design on pressure filter press time, the steam temperature, steam access time and the cake moisture and filtration rate using orthogonal respective ly diaphragm were studied, determined optimal operation conditions, and also made a comparative analysis about the micro-structure dewatering sludge of process. The results showed that: The combined effects of steam injection heating method, heating temperature between 135℃~ 145℃, the dehydration time between 25 ~ 30min, the diaphragm pressure is 0.6MPa or above, the steam access time between 350s~ 450s, and the filter cake moisture content was significantly decreased to lower than 60%.Experimental studies have shown that using steam heat-press filter dewatering sludge to senior cadres of the degree of dehydration, has high efficiency, more economic. The method of dewatering the sludge senior cadres of the degree provides a new way in the following study.