The reduction of the acid gas concentration in the flue gas of combustion units that is produced in waste incinerators, by contacting the flue gas with a powder composition including an alkaline earth metal salt and an ammonium salt. The contact may be carried out in a combustion furnace and/or in a post-combustion chamber of the combustion units.

Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

Sorbent compositions containing calcium and iodine are added to coal to mitigate the release of mercury and/or other harmful elements into the environment during combustion of coal containing natural levels of mercury.

Sorbent compositions containing calcium and iodine are added to coal to mitigate the release of mercury and/or other harmful elements into the environment during combustion of coal containing natural levels of mercury.

In a petroleum residuum burning boiler including: a high-temperature reduction combustion chamber to which petroleum residuum fuel and primary combustion air are supplied and in which combustion is performed at a temperature of 1,300° C. or more and an air ratio of less than one; and a low-temperature oxidation combustion chamber which is connected to the high-temperature reduction combustion chamber and in which combustion is performed at a temperature of less than 1,300° C. and an air ratio of one or more, an assist gas is supplied to the high-temperature reduction combustion chamber, and unburned carbon of a combustion gas of the petroleum residuum fuel is gasified by a water gas reaction by using steam, generated by combustion of the assist gas, as a gasifying agent.

In a petroleum residuum burning boiler including: a high-temperature reduction combustion chamber to which petroleum residuum fuel and primary combustion air are supplied and in which combustion is performed at a temperature of 1,300° C. or more and an air ratio of less than one; and a low-temperature oxidation combustion chamber which is connected to the high-temperature reduction combustion chamber and in which combustion is performed at a temperature of less than 1,300° C. and an air ratio of one or more, an assist gas is supplied to the high-temperature reduction combustion chamber, and unburned carbon of a combustion gas of the petroleum residuum fuel is gasified by a water gas reaction by using steam, generated by combustion of the assist gas, as a gasifying agent.

An integrated comprehensive adjustment method for a pulverized coal boiler based on high-temperature corrosion prevention and control of water wall is provided. The method includes: during shutdown period of the boiler, mounting reducing atmosphere sampling pipe on a water-cooled wall region; carrying out a diagnostic test on the boiler; carrying out an optimization and adjustment test of a boiler pulverizing system; carrying out a single-factor adjustment test of boiler-related parameters; determining degrees of influence of different parameters on water wall reducing atmosphere, thermal efficiency of the boiler and NO.sub.x concentration at a denitration inlet; carrying out an optimization test of ammonia spraying of a denitration system; carrying out a maximum safe denitration efficiency test; and finding a balance point among the water wall reducing atmosphere, the thermal efficiency of the boiler and the NO.sub.x concentration at the denitration inlet.

A burner characterized by being equipped with: a fuel supply nozzle to which a mixed flow of a solid fuel and a solid fuel transport gas is supplied; a flow passage that is arranged on the outside of the fuel supply nozzle and that supplies combustion air separated from the mixed flow; and ammonia supply nozzles which are capable of supplying ammonia on the downstream side of the outlet of the fuel supply nozzle toward a reduction region in which oxygen in the transport gas has been consumed due to ignition of the fuel and the progress of combustion, resulting in a low oxygen concentration. Thus, it is possible to provide a burner capable of burning a mixture of a solid fuel and ammonia, and a combustion device equipped with this burner.

Disclosed is a process for cleaning a boiler, wherein, while fumes are emitted in a combustion chamber of the boiler and circulate up to exchangers of the boiler, an aqueous solution of dissolved magnesium chloride and/or sulfate and/or dissolved calcium chloride is injected into the combustion chamber in the form of droplets which, by vaporization of the water of the aqueous solution, then thermal decomposition, are transformed in the combustion chamber into magnesium and/or calcium oxide particles reacting in the combustion chamber by mixing with molten salts and/or molten oxides, present in the fumes, to crystallize these molten salts and/or to vitrify these molten oxides before these molten salts and/or these molten oxides come into contact with the exchangers. Also disclosed is a device for implementing this process and a boiler equipped with this device.