Patent · US Expired

Process for improving soluble coal yield in a coal deashing process

US4225420A · kind A · utility

6Cited by
4References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 27, 1979
Grant dateSep 30, 1980
Priority date
Expiry dateJun 27, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10G1/04
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Coal liquefaction products are contacted with a deashing solvent and introduced into a first separation zone. The first separation zone is maintained at an elevated temperature and pressure, determined to maximize the recovery of soluble coal products, to cause said coal liquefaction products to separate into a first light phase and a first heavy phase. Under these conditions the heavy phase while still fluid-like in character is substantially non-flowable. Flowability is returned to the fluid-like heavy phase by the introduction of an additional quantity of deashing solvent into the first separation zone at a location below the interface between the first light and heavy phases or into the heavy phase withdrawal conduit during withdrawal of the first heavy phase and prior to any substantial pressure reduction. The first heavy phase then is withdrawn from the first separation zone for additional downstream processing without plugging either the withdrawal conduit or the downstream apparatus. The first light phase comprising the soluble coal products is withdrawn and recovered in an increased yield to provide a more economical coal deashing process.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.