Prototype Design And Experiment Based On Solar CPC Concentrated Drying Technology For Printing And Dyeing Sludge Drying

With the development of society, many problems are generated such as the energy shortage, environment pollution and so on. Environmental protection and economical efficiency is considered by different industries. Dyeing and printing industry is a traditional industry in ZheJiang province, which also release pollutants into the environment largely. At present, there has been no specific solution is put forward, mainly using the relevant data of sewage sludge and processing methods, thus unable to realize recycling and harmless to use.In this paper, a new method of sludge treatment is illustrated. By research of the solar drying technology and the low-temperature drying technology, the design of rotating CPC heating dryer is proposed firstly, with the advantages of concentrated heating technology, structure of vacuum tube and drum drying. And the device is made and tested. The main results are showed as follow:(1) Sludge drying test bench with solar energy heat pump are designed and built. Variation of air-temperature in the tube and wall-temperature are tested and analyzed in a day, verifying that the temperature of drying has reached the actual need (60℃-110℃). On the condition of no hot air, drying time above 60℃ remains six hours in a day. On the opposite condition, it can ensure the working temperature when Lack of light appears.(2)By experiment of drying sludge, drying time is recorded on the three situation. The influence of transverse temperature difference in drying tube is analyzed for the material drying. Compared with the traditional hot air dryer, the device has many advantages such as keeping the original shape of material, reduce the temperature difference on process.(3) Efficiency of rotating CPC heating dryer reaches 40%. There are 10.678k g/(d·m2) sludge processing in a day. In theory,3.2 tons of sludge can be handled in the area of 300m2, which reaches the demand of dyeing and printing industries in the north of Zhejiang province. Compared with single electrical heating device, power consumption of solar hot air heating device is reduced by 40.63%, and separate solar heating device is reduced by 73.3%.(4)Based on analysis and calculation from the experimental data, there are three conditions (0.551KW-h/kg,0.181KW·h/kg,0.928KW·h/kg) presented for power consumption on three kinds of drying model. Referring to the industrial average cost (1 Y/degree) in Zhejiang province at present, cost on three mode of sludge treatment can be calculated, and it shows the resules as follow:551 ￥/ton,181￥/ton,928￥/ton.