OCR Text |
Show INTRODUCTION To reduce our dependency on foreign oil and to increase the utilization of the abundant coal resources in this country, the U.S. Department of Energy (DOE) is pursuing both near- and long-term approaches to utilizing coal with the objective of displacing petroleum fuels from boilers and furnaces. In support of this program, the DOE Pittsburgh Energy Technology Center (PETC) operates combustion test facilities to evaluate the handling and combustion characteristics of alternate fuels, determine pollutant emissions resulting from combustion of these fuels, and develop retrofit technology as required. Emphasis is placed on assessing the technical feasibility of utilizing these fuels in boilers originally designed to burn oil. In this paper, the results of recent studies conducted with three types of alternate fuels are discussed: coal-oil mixtures (COM); solid solvent-refined coal (SRC-I); and coal-water mixtures (CWM). COAL-OIL MIXTURES The coal-oil mixture program at PETC was initiated in June 1975. Combustion studies were conducted in a 100-hp firetube boiler. The objectives were to determine major problem areas in firing COM containing 20 percent coal in a boiler designed to burn oil or gas and to evaluate corrosion and deposits after 1000 hours of operation. 2 The research program was later extended to the areas of C O M stability and 3 economics. In 1978, a larger COM Combustion Test Facility was completed at PETC. Central to the test facility is a 700-hp (24,000 lb of steam per hour) watertube boiler, which is a typical package industrial boiler designed originally for firing No. 6 fuel oil (Figure 1). In addition, the facility has fuel storage, coal preparation, coal-oil mixture preparation and storage, a dry sorbent injection system for SO2 removal, and a baghouse for 14-2 |