熱 필터프레스 技術을 통한 슬러지 脫水率 向上을 위한 硏究

Abstract

The thermal filter press dewatering(TFPD) technology to improve the dewaterability through increasing the inner vapor pressure, lowering the filtration viscosity and forming the porosity easily within cake as applying the heat at the sludge layer was developed in this study. The hot water with temperature of 95oC and pressure of 1.2kgf/cm2 was supplied to the heating plate equipped between filter plates with plate size of 470470mm and material of polypropylene. Sludge was dewaterd by supplying pressure of 5kgf/cm2 and then by squeezing pressure of 15kgf/cm2. As a results of estimating the characteristics of thermal dewatering to consider the initial water content and organic content to be influenced by a period of water shortage and rainwater, the dewatered cake water content was about 35wt% and dewatering velocity was 4DSkg/m2hr under the rainwater period, and the dewatered cake water content was about 50wt% and dewatering velocity was 1.5DSkg/m2갊hr in the case of sludge of water shortage season. These results was superior to the mechanical dewatering performance with water content of 70wt% and dewatering velocity of 0.9DSkg/m2갊hr. On the base of the results of TFPD, energy consumpted to deal with DS(Dry Solid) of 1kg was estimated by 300kJ. It was analyzed that the energy consumption of TFPD was decreased about one third with comparison to the dryer system. Dewatering velocity of this technology was faster than the one of mechanical dewatering equipment and it was easier to product low water content cake. Therefore, this technology was recognized that dewaterability was predominant because of the fast of dewatering velocity and production of low water content cake, and also this known as economical efficiency was excellent because of low energy consumption in comparison with dryer.