This report examines the impacts of coal properties on power station performance. As most of the coal used to generate electricity is consumed as pulverised fuel, the focus of the report is on performance in pulverised fuel (PF) power station units. The properties that are currently employed as specifications for coal selection are reviewed together with their influence on power station performance. Major coal-related items in a power station are considered in relation to those properties which affect their performance. There is a review of `tools’ being used for coal selection and prediction of station performance which includes an overview of the types of computer models that are available and those that are being developed. The principal coal properties that were found to cause greatest concern to operators included the ash, sulphur, moisture and volatile matter contents, heating value and grindability. Little has changed over the years in the way that coal is assessed and selected for combustion. Operators continue to use tests as specifications that were mostly developed for coal uses other than combustion. Because the procurement specifications are based on tests which do not relate well to actual practice, there is still a need for expensive large scale test burns to confirm suitability. With the advances that have been made in computer technology, there is a growing number of utilities that are adopting `expert’ unit or integrated models that aid in the planning and operation of generating units. Others have shown scepticism over the capability of devising a truly representative model of a coal combustion plant using the coal data produced from current testing procedures. Specific requirements that have been identified include the need to develop internationally acceptable methods of defining coal characteristics so that combustion plant performance can be predicted more effectively. There is also a need to establish economic parameters which can serve to measure the effects of coals on plant performance and hence on the cost of electricity.
Title: Coal specifications – impact on power station performance, IEACR/52
Author(s): Nina M Skorupska
Reference: IEACR/52
ISBN: ISBN: 92-9029-210-5
Publication Date: 01/01/1993
Pages: 12
Figures: 0
Tables: 0