Apparatus for converting a fuel to combustible gas

Claim 1

An apparatus for converting a solid and/or liquid fuel to a combustible gas utilizing solid calcium-containing particles, said apparatus comprising: A. a unitary vessel having a substantially vertical peripheral wall and a roof, the interior of the vessel being divided into at least three discrete compartments in horizontal succession by a like number of internal walls extending substantially vertically downwardly from the roof, each internal wall separating adjacent discrete compartments on each side thereof, each discrete compartment having a distributor at its base which distributes a respective fluidizing gas from a respective space beneath the distributor into the bottom of a discrete dense-phase fluidized bed of solid particles supported by and above the distributor so that each fluidized bed has a substantially distinct top surface at a respective selected top level within the respective discrete compartment, the roof over each compartment having a respective outlet for the exit of gas from the compartment, adjacent ends of adjacent discrete compartments communicating with each other via underflow weir means formed in a lower region of the common dividing wall below the top levels of the fluidized beds in the adjacent compartments so that particles pass from the lower region of one end of the fluidized bed in one compartment into the lower region of one end of the fluidized bed in the adjacent compartment, each compartment communicating with two adjacent compartments by said underflow weir means whereby particles circulate through all the beds in succession from the lower region of one bed to the lower region of the next successive adjacent bed; B. means passing a fluidizing gas which is substantially free of inert diluents at a regulated rate into the space beneath the distributor of a first compartment of the succession wherein the particles of the bed in the first compartment include particles comprising reactive CaSO 4 ; C. means passing a fuel into the first compartment wherein the fuel contacts the first bed and is converted to a combustible gas and wherein reactive CaSO 4 is reduced to reactive CaS with substantially no liberation of sulfur moiety under the influence of an oxygen-transfer mediator present in the bed, the resulting combustible gas leaving the first compartment via a respective combustible gas outlet; D. means passing a fluidizing gas containing molecular oxygen at a regulated rate into the space beneath the distributor of a second compartment which receives particles from the first compartment whereby the solids in the bed of the second compartment are fluidized under such conditions that some reactive CaS is exothermically oxidized to CaSO 4 and a gas of reduced molecular oxygen content and substantially free of sulfur moiety leaves the outlet in the roof of the second compartment; and E. means passing a fluidizing gas containing molecular oxygen at a regulated rate into the space beneath the distributor of a third compartment which receives particles including particles comprising reactive CaS from the exit of an underflow weir at its upstream end and from the downstream end of which particles pass via an underflow weir into the upstream end of the first compartment bed, the reactive CaS in the particles in the third compartment being oxidized to reactive CaSO 4 at a bed temperature such that the gas leaving the third compartment via the respective outlet in the roof comprises some molecular oxygen but substantially no sulfur moiety.

Claim 2

An apparatus for converting a solid and/or liquid fuel to a combustible gas utilizing solid calcium-containing particles, said apparatus comprising: A. a unitary vessel having a substantially vertical peripheral wall and a roof, the interior of the vessel being divided into at least three discrete compartments in horizontal succession by a like number of internal walls extending substantially vertically downwardly from the roof, each internal wall separating adjacent discrete compartments on each side thereof, each discrete compartment having a distributor at its base which distributes a respective fluidizing gas from a respective space beneath the distributor into the bottom of a discrete dense-phase fluidized bed of solid particles supported by and above the distributor so that each fluidized bed has a substantially distinct top surface at a respective selected top level within the respective discrete compartment, the roof over each compartment having a respective outlet for the exit of gas from the compartment, adjacent ends of adjacent discrete compartments communicating with each other via underflow weir means formed in a lower region of the common dividing wall below the top levels of the fluidized beds in the adjacent compartments so that particles pass from the lower region of one end of the fluidized bed in one compartment into the lower region of one end of the fluidized bed in the adjacent compartment, each compartment communicating with two adjacent compartments by said underflow weir means whereby particles circulate through all the beds in succession from the lower region of one bed to the lower region of the next successive adjacent bed; B. means passing a fluidizing gas which is substantially free of inert diluents at a regulated rate into the space beneath the distributor of a first compartment of the succession wherein the particles of the bed in the first compartment include particles comprising reactive CaSO 4 ; C. means passing a fuel into the first compartment wherein the fuel contacts the first bed and is converted to a combustible gas and wherein reactive CaSO 4 is reduced to reactive CaS with substantially no liberation of sulfur moiety under the influence of an oxygen-transfer mediator present in the bed, the resulting combustible gas leaving the first compartment via a respective combustible gas outlet; D. means passing a fluidizing gas containing molecular oxygen at a regulated rate into the space beneath the distributor of a second compartment which receives particles from the first compartment whereby the solids in the bed of the second compartment are fluidized under such conditions that some reactive CaS is exothermically oxidized to CaSO 4 and a gas of reduced molecular oxygen content and substantially free of sulfur moiety leaves the outlet in the roof of the second compartment; and E. means passing a fluidizing gas containing molecular oxygen at a regulated rate into the space beneath the distributor of a third compartment which receives particles including particles comprising reactive CaS from the exit of an underflow weir at its upstream end and from the downstream end of which particles pass via an underflow weir into the upstream end of the first compartment bed, the reactive CaS in the particles in the third compartment being oxidized to reactive CaSO 4 at a bed temperature such that the gas leaving the third compartment via the respective outlet in the roof comprises some molecular oxygen but substantially no sulfur moiety.