Application of the severity parameter for predicting viscosity during hydrothermal processing of dewatered sewage sludge for a commercial PFBC plant.
Dewatered sewage sludge (approximately 80% water, but with low fluidity) was liquidized by hydrothermal treatment in order to make coal-water paste (CWP) for use in a pressurized-fluidized-bed-combustion (PFBC) power plant. Prediction of the viscosity of the dewatered sewage sludge during batch reactor hydrothermal liquefaction is important in order to avoid inputting excess energy. A single parameter, the severity parameter, has been used to predict viscosity during the hydrothermal process. The relationship between the viscosity of the slurry made from dewatered sewage sludge and the severity value was investigated. Viscosity reduction was associated with an increase in the severity value and was dependent on reaction temperature and time. It was concluded that predicting the viscosity of dewatered sewage sludge during the hydrothermal process by means of the severity parameter is possible. This method is expected to provide a useful guideline for choosing reaction conditions based on prediction of the viscosity of the sludge slurry during the hydrothermal process.
Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology, 2-2-2 Hirosuehiro, Kure, Hiroshima 737-0197, Japan.
Takashi
T
Yanagida
Shinji
S
Fujimoto
Tomoaki
T
Minowa
D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D003031:Coal; D012722:Sewage; D013696:Temperature; D014783:Viscosity; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis
D003031:Coal; D012722:Sewage; D014874:Water Pollutants, Chemical