Influencing factors of the drying rate of sludge for solar drying chamber

Abstract

In view of the problems of low solar energy utilization efficiency, drying efficiency to be improved and sludge adhesion in the process of solar drying sludge, the research was carried out on the heat collection effect of solar collectors, sludge drying characteristics and sludge drying process, as well as the influence of sludge drying process parameters on the sludge drying rate such as hot air temperature, solar radiation intensity and air substitution,. on the self-built industrial simulation test bench. The results show that: the maximum temperature difference between the inside and the outdoor environment of the solar collectors is 36°C, when the outdoor environment temperature of the developed solar collectors is 13-26°C; the optimum process parameters of sludge drying rate under the experimental conditions that the moisture content of wet sludge is 82.7%, are as follows: the temperature of hot air is 43°C, the maximum solar radiation intensity (about 12:00), the optimal flow rate of air is controlled at 1.2m/s, the thickness of the material layer is 3cm, the large contact between air and materials improves the problem of sludge adhesion. All which provide a theoretical basis for the implementation on the industrialization of solar drying sludge.