The study of drying sewage sludge by microwave technology

• Main Authors: Yu-Sung Chiu, 邱毓松
• Other Authors: Yuan-Sheng Li
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/56156602498696247062

碩士 === 國立宜蘭大學 === 綠色科技學程碩士在職專班 === 104 === The main solid waste is produced from the wastewater treatment plant (WWTP) where municipal wastewater collected by the public sewarage system then disposed through the procedures of the plant. There are sixty four public wastewater treatment plants under the authority of Construction and Planning Agency Ministry of the Interior, more than 200 tons waste sludge are produced every day with 75 to 80 % of water content from the operation plants. By taking Ludon Wastewater Treatment plant as an example, the average increasing influent amount is more than 2,000 CMD every year, and the amount of delivery sludge is about 1,600 tons which cost 9 millions TWD for disposal which takes more than 30% of whole operation cost. The most common method of sludge drying in Taiwan is Hot Air Drying, additionally, there are Vacuum Drying, Infrared Drying, Freeze Drying, etc. This study is concentrated on dyring sludge by Microwave Drying, and the influential factors are the energy of microwave, the volume of sludge, the micorwave time, the thickness of sludge¸and so on. In this study, the factors which might have influences on the efficiency of sludge drying are investigated individually. The result of experiment indicates that the water content could be ruduced from 80% to 25% through 9 minutes micorwave, while the microwave energy is 800W with 40 gram of sludge and 0.5 cm of sludge thickness. Furthermore, the water content could be reuced from 80% to 49.6% under the same condition, but only the sludge volume rises to 240 gram. The effect of Microwave Drying is outstanding. Besides, the consumption of energy during the process of microwave is also analyzed, it only cosumes 480,000J with 800W/240g (the rate of microwave/the volume of sludge). It shows the most optimal effect of energy-saving by the adoption of combination with high rate and high volume compared to other experimental parameters.