Abstract
This chapter discusses the effect of coal preparation on the filtration step in direct liquefaction. In a study described in the chapter, coals from six mines were split into clean, middlings, and reject fractions by dense medium separations. These were then used as the feedstocks for a series of kilogram scale experiments to investigate the effect of coal cleaning on the filtration characteristics of digests produced from these coals. Digests produced from middlings contain larger quantities of mineral matter and reduced proportions of undissolved coal. This reduces the proportion of fine particles in the filter cake and explains the lower cake resistivities encountered when processing middlings. This point was illustrated by unreacted coal particles of nominally the same feed size as these coals gave a resistivity value of only 1× 10 m/kg, which is very low. Maceral separation achieved in the LARCODEMS unit produced cleans enriched in the more reactive vitrinites, whereas middlings were richer in exinites and the relatively unreactive inertinites. Generally, amounts of unconverted coal correlated well with the coal inertinite content. This could further widen the particle-size distribution and, hence, increase cake resistivity for cleans relative to middlings.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: 1991 International Conference on Coal Science Proceedings
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
