Recent developments in wet carbonization of peat

Conference · Fri Aug 01 04:00:00 EDT 1986

OSTI ID:6956177

Rue, D M; Mensinger, M C; Srivastava, V J

Wet carbonization is a generic term for a thermal beneficiation process in which wet peat is heated to temperatures of 150 to 325/sup 0/C at elevated pressures so that water present remains in liquid form. Wet carbonization produces a solid product with a higher heating value than raw peat. Wet-carbonized peat can be mechanically dewatered to a significantly lower moisture content than raw peat. A continuous-flow Process Research Unit (PRU), capable of processing 375 kg/h of peat slurry at temperatures and pressures up to 290/sup 0/C and 7.60 MPa, respectively, was used to study the effect of wet-carbonization operating conditions on the peat. Thirteen tests were made with peats from Minnesota and Maine. For the Minnesota peat tests, the feed slurry solids concentration ranged from 6.1 to 13.7%. The average reactor operating temperatures and residence times ranged from 175 to 260/sup 0/C and 1 to 60 minutes, respectively. The heating value enhancement of the wet-carbonized peats was as high as 21%, and the moisture content of mechanically-dewatered wet-carbonized peat was as low as 39% (compared with >65% for raw peat). A bench-scale, continuous two-phase anaerobic digestion system to recover energy and to treat wet-carbonization effluent water was designed, fabricated, and tested with effluent water from the PRU tests. At a short hydraulic retention time of 2.9 days, the system provided COD and BOD/sub 5/ removal efficiencies of 56 and 75%, respectively. The methane yield was approximately 86% of the average ultimate biodegradable yield. 6 refs., 10 figs., 2 tabs.

• Research Organization: Institute of Gas Technology, Chicago, IL (USA)
• DOE Contract Number: AC22-83PC60775
• OSTI ID: 6956177
• Report Number(s): CONF-8608150-1; ON: DE87003952
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300 -- Coal
Lignite
& Peat-- Preparation-- (1987-)
010409* -- Coal
Lignite
& Peat-- Pyrolysis & Carbonization-- (1987-)
ALKANES
ANAEROBIC DIGESTION
BIOCONVERSION
CALORIFIC VALUE
CARBONIZATION
CHEMICAL EFFLUENTS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMBUSTION PROPERTIES
DECOMPOSITION
DENITRIFICATION
DESULFURIZATION
DIGESTION
ENERGY SOURCES
FABRICATION
FEDERAL REGION I
FEDERAL REGION V
FOSSIL FUELS
FUELS
HYDROCARBONS
HYDROGEN COMPOUNDS
LIQUID WASTES
MAINE
MANAGEMENT
MATERIALS WORKING
METHANE
MINNESOTA
NORTH AMERICA
ORGANIC COMPOUNDS
ORGANIC MATTER
OXYGEN COMPOUNDS
PEAT
PRESSING
PROCESSING
REMOVAL
TEMPERATURE DEPENDENCE
TIME DEPENDENCE
USA
WASTE MANAGEMENT
WASTE PROCESSING
WASTE WATER
WASTES
WATER
WATER REMOVAL
YIELDS