Test Study On The New Sludge Drying Equipment Of Waste Heat Utilization

Along with the development of the economy, the environment are also increasingly suffered significant damage, sludge as by-products of the process of sewage treatment, the output is also increasing. Sludge containing a multitude of toxic and harmful substances, If the sludge treatment was inappropriated, it can cause secondary pollution. After years of research,it found that the methods of indirect heating drying sludge has obvious advantages and more extensive applying space than other sludge disposal methods.Based on sludge dewatering of the Jiang su province of sewage treatment plant, it use the device of thermal conductivity to analysis the thermal conductivity, heat coefficient, heat, temperature conductivity of sludge under different moisture, analyse the thermal and chemical properties under different moisture of sludge.In the self-simulation test device of sludge drying.it main research the impact of rate drying temperature, stirring speed to the water evaporation of sludge.In the experiment of analog drying, it found that the rate of evaporation general presents three process under drying process of low temperature, In moisture content70%-85%drying rate rise high speed,then rapid decline, Moisture content in60%-70%of evaporation there be a significant rise and then gentle downward trend, When the moisture content in below60%, the rate of evaporation slow down.In the process of drying speed and temperature plays a leading role, the biggest influence of sludge drying rate is temperature.Using of sludge drying machine to do the semi-experiment for sludge.Based on the research of heat transfer characteristics of sludge content in different moisture conditions,it found that the process of operation,the rotary speed in between5rpm and20rpm, The proportion of sludge and steam is1.3-2.0, Steam temperature is127-143degrees, The moisture content of sludge is in50%～‖65%, The thermal efficiency≥70%.If the rotary speed is slower,The sludge temperature curve is obviously statified in the monitoring sites, the lower sludge content,But the drying equipment efficiency has the reducing the trend.