An oxygen fired fluidized bed combustor system (Oxy-FBC) is provided. The system provides means of producing a nearly pure stream of carbon dioxide for storage at high efficiency by controlling the oxygen content within certain regions of the combustor to control the rate of heat release allowing efficient transfer of heat from the combustor to the boiler tubes while avoiding excessively high temperatures that will cause ash melting, and simultaneously remove sulphur from the combustor via sorbents such as limestone and dolomite. The present invention utilizes a coarse oxygen carrier bed material to distribute heat and oxygen throughout an Oxy-FBC, while injecting fine sulphur sorbent that will continuously be removed from the bed.

An oxygen fired fluidized bed combustor system (Oxy-FBC) is provided. The system provides means of producing a nearly pure stream of carbon dioxide for storage at high efficiency by controlling the oxygen content within certain regions of the combustor to control the rate of heat release allowing efficient transfer of heat from the combustor to the boiler tubes while avoiding excessively high temperatures that will cause ash melting, and simultaneously remove sulphur from the combustor via sorbents such as limestone and dolomite. The present invention utilizes a coarse oxygen carrier bed material to distribute heat and oxygen throughout an Oxy-FBC, while injecting fine sulphur sorbent that will continuously be removed from the bed.

Disclosed is a catalyst for desulfurization, including (a) an oxide selected from among SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, TiO.sub.2, MgO, MnO, CaO, Na.sub.2O, K.sub.2O and P.sub.2O.sub.3, (b) a metal selected from among Li, Cr, Co, Ni, Cu, Zn, Ga, Sr, Cd and Pb, and (c) a liquid compound selected from among sodium tetraborate (Na.sub.2B.sub.4O.sub.7.10H.sub.2O), sodium hydroxide (NaOH), sodium silicate (Na.sub.2SiO.sub.3) and hydrogen peroxide (H.sub.2O.sub.2). The catalyst of the invention has a 2:1 type layered structure in which one octahedral layer is interposed between two tetrahedral layers and which has a net negative charge due to occupation of only two of three positively charged sites in the octahedral layer, and the catalyst for desulfurization is provided in the form of a metal chelate compound through chelation with a metal ion, whereby sulfur oxide (SO.sub.x) can be adsorbed and removed at high efficiency upon combustion of a combustible substance.

Disclosed is a catalyst for desulfurization, including (a) an oxide selected from among SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, TiO.sub.2, MgO, MnO, CaO, Na.sub.2O, K.sub.2O and P.sub.2O.sub.3, (b) a metal selected from among Li, Cr, Co, Ni, Cu, Zn, Ga, Sr, Cd and Pb, and (c) a liquid compound selected from among sodium tetraborate (Na.sub.2B.sub.4O.sub.7.10H.sub.2O), sodium hydroxide (NaOH), sodium silicate (Na.sub.2SiO.sub.3) and hydrogen peroxide (H.sub.2O.sub.2). The catalyst of the invention has a 2:1 type layered structure in which one octahedral layer is interposed between two tetrahedral layers and which has a net negative charge due to occupation of only two of three positively charged sites in the octahedral layer, and the catalyst for desulfurization is provided in the form of a metal chelate compound through chelation with a metal ion, whereby sulfur oxide (SO.sub.x) can be adsorbed and removed at high efficiency upon combustion of a combustible substance.

Disclosed is a desulfurization system using a catalyst for desulfurization, including a coal feed unit for conveying a combustible substance, a spray unit for spraying a catalyst for desulfurization, a coal pulverization unit for pulverizing the combustible substance conveyed from the coal feed unit, and a combustion unit for combusting the pulverized combustible substance, wherein during transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed using the spray unit and is mixed with the combustible substance. The desulfurization system of the invention can be simply and easily applied to various combustion facilities because, during the transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed and is mixed with the combustible substance, thereby efficiently reducing sulfur oxide (SO.sub.x) emission due to combustion of fossil fuel.

Disclosed is a desulfurization system using a catalyst for desulfurization, including a coal feed unit for conveying a combustible substance, a spray unit for spraying a catalyst for desulfurization, a coal pulverization unit for pulverizing the combustible substance conveyed from the coal feed unit, and a combustion unit for combusting the pulverized combustible substance, wherein during transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed using the spray unit and is mixed with the combustible substance. The desulfurization system of the invention can be simply and easily applied to various combustion facilities because, during the transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed and is mixed with the combustible substance, thereby efficiently reducing sulfur oxide (SO.sub.x) emission due to combustion of fossil fuel.

A combustion device includes: an ammonia injection nozzle having an injection port facing an internal space of a furnace; a pulverized coal injection nozzle having an injection port facing the internal space of the furnace; an adjustment mechanism that adjusts an injection flow rate of ammonia from the ammonia injection nozzle; and a control device that controls an operation of the adjustment mechanism in such a manner that the injection flow rate of ammonia from the ammonia injection nozzle is higher than an injection flow rate of pulverized coal from the pulverized coal injection nozzle.

A special distribution of nozzles in the flue gas outlet and their alignment make it possible to guide the flue gas along a wavy line. The addition of combustion air for primary air and secondary air can be variably distributed during operation of the combustion plant, for example so as to also keep the burnout per unit of time constant while maintaining a constant combustion air ratio.

A special distribution of nozzles in the flue gas outlet and their alignment make it possible to guide the flue gas along a wavy line. The addition of combustion air for primary air and secondary air can be variably distributed during operation of the combustion plant, for example so as to also keep the burnout per unit of time constant while maintaining a constant combustion air ratio.

Provided are water-based fuel additive compositions that, when combusted with a fuel containing vanadium in a gas turbine, inhibit vanadium hot corrosion in the gas turbine. The water-based fuel additive compositions include at least one rare earth element compound or alkaline earth element compound that retards vanadium corrosion resulting from combustion of vanadium rich fuel.