Analysis of inorganic constituents deposited in a 150 T/day coal liquefaction pilot plant

A wide variety of inorganic constituents were deposited in several units of the NEDOL coal liquefaction pilot plant with a capacity of 150 tons per da y. The inorganic constituents were analyzed by CCSEM, XRD and XRF. In the f irst liquefaction reactor, the growth of crystalline quartz and the interac tion of calcium with mineral and/or catalyst were observed to be significan t. The inorganic particles of larger size (> about 100 mum) were accumulate d in the first liquefaction reactor while the smaller particles were flushe d out to downstream. The small catalyst particles were mainly accumulated i n the high-temperature separator and the other interacted particles were ma inly accumulated in the outlet pipe after letdown valve.