| OCR Text |
Show INTRODUCTION At current prices, coal of a reasonable heating value is selling for $1.50 to 2.00/10° Btu. Comparable prices for oil and gas range broadly depending on location, but $4.00 to 6.00/10 Btu is a reasonable range to consider for cost comparison. Because of the significant potential cost savings of using coal, many methods have been considered for converting industrial boilers and process heaters to fire pulverized coal or fuels containing significant quantities of pulverized coal. To date there have been three basic options to consider on converting existing process heaters or industrial boilers to fire coal. - Use of coal/oil mixtures - Use of coal/water mixtures - Direct firing of pulverized coal The first two options are attractive because large on-site coal handling facilities are not required and the economics of large scale off site preparation plants can be used to minimize fuel preparation costs. The third option, while based on proven technology, is capital intensive and, because of space requirements, may be difficult or even impossible for many existing plants. There are also many other factors that must be considered, such as the effects of coal ash on boiler or process performance and the need for stack gas cleanup to remove sulfur and particulates to meet state and federal environmental limits. While these factors may, in the final analysis, dictate the feasibility of using coal in a particular application, a detailed review of their impact is well beyond the scope of this paper. References 1 - 3 deal with these questions in fair detail and should be reviewed before serious consideration is given to coal conversion. The thrust of this paper is to look at a fourth option for converting to coal firing. This option is the use of bulk storage and dense phase transport of pulverized coal and is based on the technology C-E has developed as part of our Direct Ignition of Pulverized Coal (DIPC) system. 11-2 |
