Direct liquefaction of low-rank coal. Quarterly technical progress report, July 1, 1995--September 30, 1995

A multistep direct liquefaction process specifically aimed at low-rank coals (LRCs) has been developed at the Energy & Environmental Research Center (EERC). The process consists of a preconversion treatment to prepare the coal for solubilization, solubilization of the coal in the solvent, and polishing using a phenolic solvent or solvent blend to complete solubilization of the remaining material. The product of these three steps can then be upgraded during a traditional hydrogenation step. This project addresses two research questions necessary for the further development and scaleup of this process: (1) determination of the recyclability of the solvent used during solubilization and (2) determination of the minimum severity required for effective hydrotreatment of the liquid product. The project is being performed as two tasks, the first consisting of ten recycle tests and the second consisting of twelve hydrotreatment tests performed at various conditions. Several activities were performed during this quarter. (1) A paper entitled {open_quotes}Solvent Recyclability in a Multistep Direct Liquefaction Process{close_quotes} was presented at the 1995 Coal Liquefaction and Gas Conversion Contractors{close_quote} Review Conference that was held in Pittsburgh, PA, August 29-31, 1995. (2) The Task 1 solvent recyclability tests were completed. (3) The Task 1 quality assurance/quality control checks were performed. (4) The first seven Task 2 hydrotreatability tests were completed. Analysis of the Task 1 data indicates that (1) the multistep process produces adequate quantities of excess solvent for recycle and (2) the product slates of all of the tests were fairly consistent