NIOSHTIC-2 Publications Search

Upgrading Mississippi lignite by hydrothermal/chemical pretreatment.

Williford CW Jr.
For Reference Only At Bureau Libraries :14 pages
Low-rank coals represent a major energy resource for the United States. Their use will be promoted by legislation to control sulfur emissions. Despite the size of the resource, however, lignite has several properties that have limited commercialization. These include relatively high moisture and ash contents and low heating value. These characteristics have made lignite more expensive and technically difficult to transport and to burn. Several physical and chemical pretreatments have been developed for application to low-rank coals. To date, most studies have focused on lignites in the Northern Plains States. In this project we have applied two pretreatments to Mississippi lignite, assessed the impact on properties, and related these results to the existing database for upgraded low-rank coal fuels. Specifically, we hydrothermally pretreated and alkylated a sample of Mississippi lignite. The hydrothermal pretreatment was carried out at 240 deg c in a sealed tube bomb. Results show a reduction in heating value and an increase in ash content of the recovered coal. This suggests a removal of substantial amounts of volatiles, probably aliphatic as indicated in related work. The alkylated coal had a higher heating value. Some of the increase can be attributed to the additional functional groups. In summary, we have applied state-of-the-art pretreatments to Mississippi lignite. The effect on key properties has been assessed and related to current understanding. The work directly addresses and seeks solutions to the most critical needs that currently limit commerci
Publication Date
Document Type
CP; Final Contract Report
Fiscal Year
Identifying No.
OFR 33-92
NIOSH Division
Source Name
For Reference Only At Bureau Libraries
Performing Organization
University of Mississippi
Page last reviewed: December 30, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division