Effects of Start-Up Solvent on Composition of Recycle Liquefaction Product Slurry from Low-Rank Coal

摘要

As part of the on-going research in the liquefaction of low-rank coal, the University of North Dakota Energy Research Center (UNDERC) carried out two bottoms recycle runs. The purpose of these 40 pass runs was to investigate the effect of two different start-up solvents on the composition of the product from pass to pass, especially the bottoms portion used as recycle solvent, and the final lined-out composition of the product. Runs 101 and 103 were carried out in the bottoms recycle mode in the Continuous Processing Unit (CPU). Zap, North Dakota lignite from the Indian Head mine was introduced at 5 lbs/h as a 30% slurry (wt % as-received coal) in recycle feed with H sub 2 S addition in both runs. The nominal temperature was 440 exp 0 C and the nominal pressure was 4000 psig H sub 2 /CO (95/5). The startup solvent for Run 101 was a typical anthracene oil, A04. Run 103 was started up with a Process Development Unit (PDU) recycle solvent obtained from the University of North Dakota Chemical Engineering Department's Project Lignite. The PDU solvent was derived from Zap, North Dakota Indian Head lignite. The liquefaction products were examined from pass to pass in order to follow the compositional changes as the reaction proceeded toward steady-state composition (lineout) and to determine whether the products were chemically the same for both runs after 40 reactor passes. The preliminary characterization of the separated heavy products and their composition as compared with the composition of the oils are the focus of this report. Changes in the startup solvent as it reacts with coal and is diluted by coal-derived products are discussed with emphasis on the heavy components. Differences between the two runs started up with different solvents are described. 7 references, 5 tables. (ERA citation 09:032449)