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Show INTRODUCTION Over the past several years, the Pittsburgh Energy Technology Center (PETC) of the U.S. Department of Energy (DOE) has conducted several alternate-fuel combustion studies with the objective of developing retrofit technology that will permit the use of coal slurries in place of fuel oil in oil-designed boilers. Coal slurries that have been evaluated at PETC include coal-oil mixtures, coal-water mixtures, and coal-methanol mixtures. Coal-oil mixtures (COM) have the potential for partially displacing petroleum used in existing oil-fired industrial and utility boilers. After two and a half years of" systematic study, the COM combustion program carried out in an oil-designed 700-hp watertube boiler was successfully completed in the spring of 1981 (1-4). Coal-water mixtures (CWM) -and coal-methanol mixtures (CMM) have the potential for fully displacing petroleum fuels used in oil-fired boilers. Coal-water mixtures were burned earlier in pulverized-coal-designed boilers (5-7), and more recently CWM tests have been conducted in small scale furnaces (8-11). A CWM combustion program was initiated at PETC after the completion of its COM combustion program. The initial phase of the program was carried out using a 100-hp fire-tube boiler; a more comprehensive program is being conducted in the 700-hp watertube boiler. The objectives of the PETC CWM combustion program have been to prepare CWM with coal concentrations that result in acceptable mixing and transport characteristics, to achieve stable CWM flames in boilers without supplemental fuel assist, and to establish CWM combustion characteristics. A coal-methanol mixture (CMM) combustion program is also underway using the 100-hp firetube boiler. Objectives of the CMM program are similar to those discussed in regard to CWM. Combustion tests carried out at PETC have demonstrated that COM, CWM, and CMM can be burned in oil-designed boilers with modest boiler and facility modifications. In this paper, the retrofit technology 14-2 |