下水汚泥の低温造粒乾燥による臭気?燃料化率への影響

摘要

湿潤バイオマスの固形燃料製造プロセスにおいて，乾燥工程の前処理工程として200℃以下の低温熱を利用した加熱処理を行うことにより，揮発分の揮散を抑制して高い燃料化率を維持し，かつ悪臭の発生を大幅に抑制した燃料を製造する「表面固化処理技術」に関する研究開発を行った。200℃表面固化と120℃燃料化処理を組み合せた表面固化処理技術を用いることにより，下水汚泥燃料化物の臭気強度を2に抑えるとともに，燃料化率を96.2%に維持できた。%A study was carried out on the surface solidification drying technology to produce bio-solids from sewage sludge with high energy conversion efficiency and at reducing unbearable odors of the solid fuels substantially by utilizing a low-grade heat source of below 200℃ as a pre-process of the drying system to minimize volatilization loss of the volatile matter in the sewage sludge. As a result, the targets of odor intensity and energy conversion efficiency were attained: solid fuels from the sewage sludge were produced at odor intensity of equal to or less than 2 and energy conversion efficiency of 96.2% from sewage sludge to solid fuels by the surface solidification and drying technology that used a combination process of the surface solidification at 200℃ and the conversion into solid fuels at 120℃.