The researcher inquired drying characteristics by reflecter shape. Near infrared ray (NIR) is very useful in various drying field. The researcher compared and investigated, temperature about reflecter's shape with numerical analysis method and experimental method. The researcher also investigated about distance between a lamp and a drying target plate using experimental method. As far as a experimental method is concerned, the researcher used the thermal image processing system for changing distance between a lamp and a drying target plate into H=500mm, 600mm and 700mm. Also presented experimental results are compared about thermal image for temperature distribution at each cases. As a result, the researcher has come to the H=700mm about best result in this study.

This study executed evaluation of drying characteristics based on the polymer injection rate (8%, 10% and 12%) and the drying method[NIF(near-infrared ray). According to this study analyzed VS, VS/TS, and calorific value compared with ‘the auxiliary fuel standard of the thermoelectric power plant and the combined heat & power plant’. The results are as follows. In the case of NIR, the VS was slightly changed at the early stage of the material preheating period and the constant drying rate period with low moisture evaporation. But VS reduction was shown higher as moisture was dried. In the case of non-digested sludge with high VS content, the VS reduction rate by drying was shown lower than that of digested sludge. As the flocculant injection rate increased, the VS loss due th drying was found to be small. Also, the higher the flocculant injection rate was the longer the drying time. Especially, in the case of the NIR drying equipment, as the moisture content of sewage sludge decreased(moisture content 20∼40%), the loss of net VS also showed a tendency to increase sharply. It is shown that the high calorific value according to the drying time of the non-digested sludge was changed from 590 ㎉/㎏ to 3,005 ㎉/㎏ and from 539 ㎉/㎏ to 2,796 ㎉/㎏.