Wet carbonization PDU studies

Conference · Thu Oct 01 04:00:00 EDT 1981

OSTI ID:5443535

Lau, F S; Paganessi, J E; Punwani, D V

Peat has an excellent potential to become a viable fuel source because of its low sulfur content and high reactivity. However, when harvested from the bog it can have moisture content as high as 98%. The dewatering method used after harvesting determines to a large extent the cost of peat, and whether or not peat will become an economically viable chemical feedstock or fuel. Wet carbonization is a thermochemical beneficiation process wherein the physical and chemical nature of a carbonaceous material is altered. This process can improve the mechanical dewaterability, increase the heating value, and produce a usable chemical feedstock from the wet peat. The process of wet carbonization consists of heating peat-water slurry at elevated pressures to disrupt the colloidal nature of the feed material by breaking carboxyl and hydroxyl groups from the molecular structure of the feed material resulting in an improvement of the feed material's mechanical dewaterability. Breaking of carboxyl and hydroxyl groups results in removal of oxygen from the carbonaceous material as carbon oxides and water, and also increases the heating value of the final product. As a feedstock for a gasification plant, wet carbonized peat requires less oxygen for gasification, and also produces less carbon dioxide that must be removed downstream in the acid-gas removal system than raw peat. The results of laboratory-scale wet carbonization tests are very encouraging. The data show that wet-carbonized peat can be mechanically dewatered (in a laboratory press) to moisture contents as low as 27%, and that the heating value can be increased as much as 33% over that of raw peat. Associated with wet carbonization is the loss of oxygen and carbon in peat.

• Research Organization: Institute of Gas Technology, Chicago, IL (USA)
• OSTI ID: 5443535
• Report Number(s): CONF-8110190-2; ON: DE82902688
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010401* -- Coal & Coal Products-- Carbonization-- (-1987)
010600 -- Coal
Lignite
& Peat-- Properties & Composition
CALORIFIC VALUE
CARBONIZATION
CHEMICAL REACTIONS
COMBUSTION PROPERTIES
DECOMPOSITION
ENERGY SOURCES
FOSSIL FUELS
FUELS
ORGANIC MATTER
PEAT
REMOVAL
WATER REMOVAL