FINAL TECHNICAL REPORT

September 1, 1994, through August 31, 1995

Project Title: PRODUCTION OF COMPLIANCE COAL FROM ILLINOIS BASIN COALS

ICCI Project Number: 94-1/1.1B-3

Principal Investigator:  Steven R. Hadley, Praxis Engineers, Inc.

Other Investigators:  Latif Khan, Illinois State Geological Survey

Project Manager:  Ken Ho, ICCI

ABSTRACT

The relatively high organic sulfur content of most Illinois basin coals precludes the production of compliance coals from them.  However, a number of these coals contain low orgnic sulfur and easy-to-liberate pyritic sulfur thus making them potential candidates for producing compliznce fuels with appropriate processing.  Currently, these coals are combined with toher coals before cleaning.  The objective of this project is to test whether complizance coals can be produced from selected Illinois Bain coals.  The project methodology consists of crushing the run-of-mine coal to topsizes of 3", 3/4", and 1/8" and conducting washability studies to determine the optimal topsize to which a particular coal must be crushed to achieve significant liberation.  This is followed by low-gravity separation of the coarse (+28 mesh) fraction into two products:  a compliance coal and a middlings fraction.  The middlings fraction and the minus 28-mesh natrual raw coal fines are further comminuted to minus 200 mesh to liberate the ash and pyritic sulfur and processed in an advanced flotation device (packed column cell) to obtain another compliance product.  The composite product is then evaluated as a compliance coal product.

An Illinois preparation plant reating raw coal and producing a middlings fraction was identified jiontly with ISGS, and samples of the plant feed coal and middlings were collected.  Liberation studies were conducted to determine the nominal topsize to which the raw coal must be crusehd and the specific gravity of separation for producing coarse compliance coal.  The comminuted middlings and natural fines (minus 28 mesh) were cleaned separately in a packed column.