title: A study on torrefaction of sewage sludge to enhance solid fuel qualities.
abstract: Torrefaction is a treatment which serves to improve the properties of biomass in relation to thermochemical processing techniques for energy generation. In this study, the torrefaction of sewage sludge, which is a non-lignocellulosic waste was investigated in a horizontal tubular reactor under nitrogen flow at temperature ranging from 150 to 400°C, for torrefaction residence time varying from 0 to 50 min. The torrefaction kinetics of sewage sludge was studied to obtain the kinetic parameters. The torrefied sewage sludge products were characterized in terms of their elemental composition, energy yield, ash content and volatile fraction. The energy and mass yields decreased with an increase in the torrefaction temperature. From an elemental analysis, the weight percentage of carbon in the sewage sludge increased with an increase in the torrefaction temperature. On the other hand, the weight percentages of hydrogen and oxygen tended to decrease. The gaseous products from torrefaction of sewage sludge were also analyzed. From this work, it was found that the compounds with oxygen were emitted at a temperature lower than that for hydrocarbon gases and the temperatures of 300-350°C were the optimum torrefaction temperatures for sewage sludge.
authors: Department of Mechanical Engineering, Kongju National University, 1223-24 Cheonan-Daero, Seobuk, Chungnam 330-717, Republic of Korea.
authors: Jeeban
authors: J
authors: Poudel
authors: Department of Civil and Environmental Engineering, Hanbat National University, 125 Dongseo-Daero, Yuseong, Daejeon, 330-717, Republic of Korea.
authors: Tae-In
authors: TI
authors: Ohm
authors: Korea Institute of Energy Technology Evaluation and Planning, 135-502 Teheran-ro 114gil 14, Gangnam-gu, Seoul, Republic of Korea.
authors: Sang-Hoon
authors: SH
authors: Lee
authors: Department of Environmental Engineering, Kongju National University, 1223-24 Cheonan-Daero, Seobuk, Chungnam 330-717, Republic of Korea. Electronic address: ohsec@kongju.ac.kr.
authors: Sea Cheon
authors: SC
authors: Oh
mesh_terms: D056804:Biofuels; D018533:Biomass; D002244:Carbon / Q000737:chemistry; D004867:Equipment Design; D005740:Gases; D006358:Hot Temperature; D006859:Hydrogen / Q000737:chemistry; D007700:Kinetics; D008031:Lignin / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D056910:Republic of Korea; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D013818:Thermogravimetry; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical; D018508:Water Purification / Q000379:methods
chemical_list: D056804:Biofuels; D002244:Carbon; D005740:Gases; D006859:Hydrogen; D008031:Lignin; D010100:Oxygen; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical; C036909:lignocellulose
keywords: Elemental analysis; Energy yield; HHV; Mass yield; Sewage sludge; Torrefaction