Conversion of Solid Waste to Liquid Fuel

Abstract

A background in the chemistry of cellulose pyrolysis and hydrogenation is provided, and the cellulose liquefaction literature and state of the ait is reviewed. A concept of an ultimate process in which cellulosic solid waste is used both to produce process hydrogen by the water-gas shift reaction and to provide the raw material for conversion to oil is de veloped. The theoretical yield of hydrocarbon oil C_nH_2n-2 from cellulose is 35.7 weight % or 2.47 bbl/ton at 0.810 specific gravity. An economic process will probably use a reaction medium of cellulosics slurried in oil and will require a catalyst that permits operations at pressures below 1000 psig. The heating value of refuse is approximately 5000 Btu/lb, on an as, is basis and 9000 Btu/lb on a moisture and ash-free basis. At present, pyrolysis processes are capable of produc ing a tar (containing 20 weight % oxygen) with a heating value of 12,000 Btu/lb and an equal yield of char. Hydrogena tion processes have the potential of producing practically oxygen-free oil approaching 18,000 Btu/lb, without the char byproduct.