High-ash coals

Hot corrosion may also occur in breeder reactors when the fission products deposit on the stailness steel cladding as complex salts based on Csl and Cs20. This mode of corrosion occurs in boilers and turbines burning high-ash coal or residual fuel oil well as well as heat exchangers, alkali-carbonate-based fuel cells and carbonate storage systems. 

It would be quite impractical for a power utility plant to use the raw coal input to Plant C because of the likelihood emission standards would be out-of-compliance more frequently than regulations permit. Likewise, the high ash in the raw coal feed to Plant A makes it very undesirable for utility boiler applications. These high-sulfur high-ash coals must be cleaned, otherwise there would be essentially no market for them. 

After the reserves of high quality coal have been exhausted, it will be necessary to use brown coals with more impurities. Extremely high-ash coals with high alkaline contents must be used in some countries even though the performance of such fuels could not be controlled with the combustion technologies available in the past. 

Research of gasification of Ukrainian high-ash coal, USA and Australian coals for generation of synthesis gas with high content of hydrogen (1997-2004)... 

DEVELOPMENT OF PCFB-1.0 PILOT PLANT FOR CONVERSION OF HIGH-ASH COAL... 

The technology of conversion of Ukrainian high-ash coals in pressurized circulating fluidized bed was developed in Coal Energy... 

Levine, J.R. 1991a. New methods for assessing gas resources in thin-bedded, high-ash coals. In Proceedings, 1991 Coalbed Methane Symposium, Tuscaloosa, AL, Paper 9125, pp. 115-125. 

Combustion in a fluidized bed has some particular benefits inclnding snitability for use with low-grade, high-ash coals and the lower bed temperatures compared to those in a conventional furnace. 

The solvent refined coal (SRC) process has been conveniently described in two forms the SRC 1 process and the SRC 11 process (Schmid, 1975 Baughman, 1978). In the SRC I process, high-sulfur, high-ash coals are converted to a low-ash solid fuel whereas the SRC II process results in a liquid product (rather than a solid product) from a recycle of the product slurry, thereby increasing the conversion of the coal to lower molecular weight species (Figures 19.11 and 19.12). 

Ash from coal dissolves in the slag and dilutes the zinc content. This tends to reduce zinc recovery and hence low ash coals generally give higher zinc recovery. The use of high ash coal at the expense of zinc recovery may, however, be justified by the lower price of that coal. 

Industrial Coal Gasification Technologies Covering Baseline and High-Ash Coal, First Edition. 

Combustion characteristics of high ash coal in a pulverized coal combustion. Fud, 80 (10), 1447-1455. 

Table 5.10 presents the information about the selected standard and high-ash coals. The values for the standard Pittsburgh No. 8 (Pitt 8) coal are talcen from literature [57], whereas the analysis of the high-ash South African (SAf) coal was obtained in laboratory at the Institute of Energy Process Engineering and... 

The Lurgi FBDB gasifier can cope with the largest spectrum of coals and remains the first choice for processing high-ash coals. A combined ash and moisture... 

Based on conclusions from the Ruhr 100 that the most significant decrease of the capital costs is observed changing from 27 to 60bar design pressure [199], Weiss [193] recently introduced the new 60 bar design called Mark Plus. The development mainly aims at the SNG market in China and the capitalization of low-rank and/or high-ash coals. The new development is based on the three... 

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