A Study Of Sludge Vetor Drying And Pyrolysis Characteristics

In recent years, the amount of sludge increase quickly. With the technical improvement and innovation, the properly and scientifically dealing with these huge amount of sludges, improving the efficiency of the sludge treatment systems have become a sensitive global environment problem.Furthermore, It is outstanding with some traditional dispoal routes bringing second pollution, the final objective of sewage sludge is to meet the requirements of decrement, stabilization, detoxification, the main tendency is energy and resources recycle at home and abroad.So we should strengthen to dry and study of sludge heat treatment. Sludge combustion technology for laying a theretical foundation is an importang value in engineering and academic significance.This paper first discusses the sludge vector drying, the sawdust ratio and dry temperature were discussed on dry characteristic,adding a certain proportion of sawdust ratio in sludge, can effectively break the sludge rubber group’s imprisoned function to water and obstain huge drying surface, enhance drying heat and mass transfer efficiency hugelg, debase the energy and cost of resoures. The study shows that, within a certain proportion of adding, as the adding proportion of wood increases, time of drying sludge shortened, but when this ratio is higher than30%,less time will be not particularly evident, so determining the best adding is30%;The rising of temperature is very favorable of drying sludge, but this is the cost of energy consumption, so it is not better under the higher temperature. During improving the drying efficiency, the benefit of economic must be considered, so determining a temperature under the best ratio,180℃is the suitable temperature in this thesis.Based on drying, discusses engineering calculation that the flue gas dry sludge, the hot medium of drying sludge has a lot, this paper studies the abandoned gas dry sludge.Flue gas comes from power plant factory, flue gas produced was calculated, this also is a effective way to use sludge of resource and reasonable.The last part discusses pyrolysis of sewage sludge、combustion、kinetics. According to the thermogravimetric curve and differential thermogravimetric curve, the pyrolytic reaction of sewage sludge consisted of four stages, that is, dehydration, organic compound decomposition. By means of Coats-Redfern method, the kinetic parameters, the pre-exponential factor and the activation energy, were calculated to obtain the kinetic equation. These provided the correlative basic data for designing burner.