Abstract: A method of reducing the amount of gaseous sulfur compounds released during combustion of sulfur-containing fuel, comprising the steps of: (a) preparing a mixture of sulfur containing particulate fuel and a sulfur absorbent, such as calcium oxide, calcium hydroxide, calcium carbonate, lime, limestone, dolomite, or mixtures thereof; (b) exposing the mixture to a reducing atmosphere at a temperature of at least about 1500.degree. F., so as to convert at least a portion of the particulate fuel into a gaseous portion and a solid, char portion; and (c) combusting the char portion, thereby forming an ash containing sulfur fixed therein.

Abstract: The present invention discloses a novel method of operating a gasifier for production of fuel gas from carbonaceous fuels. The process disclosed enables operating in an entrained mode using inlet gas velocities of less than 7 feet per second, feedstock throughputs exceeding 4000 lbs/ft.sup.2 -hr, and pressures below 100 psia.

Abstract: Operation of a multiple solids fluidized-bed black liquor combustor employing only combustion residue solids as both fine and coarse bed solids is disclosed. Under normal operating conditions, a solids distribution of fine particle sizes and coarse particle sizes with a minimal population of intermediate particle sizes is maintained. Heat and chemical values are readily recovered from the black liquor and the necessity for separation of the combustion residue salts from inert fluidized-bed solids is avoided.

Abstract: A process for treating solid particles (66) of a raw carbonaceous fuel (62) such as coal having an original sulfur content comprises producing (at 68) a slurry (74) of a quantity of the raw fuel particles and a liquid medium (70) comprising water, at least one alkali metal compound including a substantial amount of sodium or potassium sulfide or polysulfide or a combination thereof, and a catalytic agent (72) comprising calcium or magnesium oxide or carbonate, or dolomite. The slurry is subjected (in 78) for an effective period of time to elevated temperature and pressure effective with the alkali metal compounds and water to cause the medium to penetrate the microscopic structure of the particles and to chemically and physically incorporate a substantial amount of the catalytic agent into the structure. The readily separable medium is separated (at 84) from the fuel particles and the particles are washed (at 84,106) to produce a particulate fuel product (88,110) containing the incorporated catalytic agent.

Abstract: An improved system for producing methane-containing product gas by the hydrogasification process. With the system, solid municipal waste is comminuted and dried following which it is introduced to the lock hopper receivers for transference to an elongate hydrogasification reactor. Synthesis gas is introduced to a lower region of the reactor and the comminuted waste, including inorganic materials, is dried and converted to methane-containing product gas and char. The char is removed from the system by a variety of separation systems including cyclone separators or aspirators and the inorganic fractured waste materials pass through the reactor but are undamaged and in a sterile condition ideally suited for recovery. A gasification reactor is incorporated with the system which receives char from the process as well as oxygen to produce the synthesis gas utilized in the hydrogasification reactor.

Abstract: Solid waste is fed to a confined zone under pressure and contacted with hydrogen containing gas. Partial conversion of the solid waste to methane occurs and the methane containing gas mixture is removed from the confined zone; it is subsequently purified and methanated so as to be a replacement for natural gas. The remainder of the solid waste is discharged from the confined zone as a carbon containing char which is delivered to a separate reaction zone where it is contacted with steam and oxygen under pressure to convert it to synthesis gas (a mixture of hydrogen, water vapor, carbon monoxide and carbon dioxide). The synthesis gas is drawn from the reaction chamber and serves as the hydrogen feed gas into the confined zone. Between the two zones, metal and glass are separated from the char by virtue of their much higher density than the carbonaceous char by entrainment of the char in a jet of steam.