Abstract: There is described an improved coal liquefaction quenching process which prevents the formation of coke with a minimum reduction of thermal efficiency of the coal liquefaction process. In the process, the rapid cooling of the liquid/solid products of the coal liquefaction reaction is performed without the cooling of the associated vapor stream to thereby prevent formation of coke and the occurrence of retrograde reactions. The rapid cooling is achieved by recycling a subcooled portion of the liquid/solid mixture to the lower section of a phase separator that separates the vapor from the liquid/solid products leaving the coal reactor.

Abstract: A method for continuously reacting particulate solids with gases and/or vapors at elevated pressures by feeding the particulate solids into a reaction zone under the pseudohydrostatic pressure generated by very tall fluidized columns of particulate solids, with the descent velocity of the solids and gas in the columns being greater than the ascent velocity of the gas. Fluidizing gas is preferably used at selected points in the column in order to avoid a harmful compaction of the particulate solids.

Abstract: Pulverized coal having a sulfur content of up to 2.5% is introduced into a gasification vessel together with air preheated to a temperature above 900.degree. F. The pulverized coal and preheated air react in the gasification vessel which is operated at temperatures in excess of 1800.degree. F. with a residence time of less than three seconds therein. The reaction between the concurrent downwardly flowing coal and air produces a product comprising partially gasified char entrained in a product gas comprising methane, hydrogen, hydrogen sulfide and oxides of carbon. The partially gasified low sulfur char entrained in the product gas is withdrawn from the gasifier and conducted to a waste heat boiler to provide steam as a source of energy for power generation. Thereafter, the low sulfur char is separated from the product gas and fed to a char storage hopper which maintains the char at a temperature above 900.degree. F. and preferably above 1100.degree. F.

Abstract: A method and apparatus for removing oversized, unentrained char particles from a two-stage coal gasification process so as to prevent clogging or plugging of the communicating passage between the two gasification stages. In the first stage of the process, recycled process char passes upwardly while reacting with steam and oxygen to yield a first stage synthesis gas containing hydrogen and oxides of carbon. In the second stage, the synthesis gas passes upwardly with coal and steam which react to yield partially gasified char entrained in a second stage product gas containing methane, hydrogen, and oxides of carbon. Agglomerated char particles, which result from caking coal particles in the second stage and are too heavy to be entrained in the second stage product gas, are removed through an outlet in the bottom of the second stage, the particles being separated from smaller char particles by a counter-current of steam injected into the outlet.