A process for nitrification, in the heterogeneous phase, of the flue gases produced by a combustion furnace (1), in particular a furnace for incinerating waste or sludge from a municipal water or industrial water purification plant, according to which the fuel is introduced into a fluidized bed (B) or onto a grate, and combustion air (2) is injected into the furnace; a reducing agent (6) is injected into the fuel and/or into the combustion air, upstream of the combustion chamber (H), and is mixed homogenously with the fuel and/or the combustion air, in order to carry out a reducing treatment promoted by the bed (3) of ash or of solids present in the furnace.

A process for nitrification, in the heterogeneous phase, of the flue gases produced by a combustion furnace (1), in particular a furnace for incinerating waste or sludge from a municipal water or industrial water purification plant, according to which the fuel is introduced into a fluidized bed (B) or onto a grate, and combustion air (2) is injected into the furnace; a reducing agent (6) is injected into the fuel and/or into the combustion air, upstream of the combustion chamber (H), and is mixed homogenously with the fuel and/or the combustion air, in order to carry out a reducing treatment promoted by the bed (3) of ash or of solids present in the furnace.

Various embodiments of a system for the removal of particulate emissions from an electric generating unit are provided, comprising: a gas producer; a primary particulate collector unit including: a primary collection hopper field each including at least one primary collection hopper, wherein each primary collection hopper includes a primary collection hopper outlet, each primary collection hopper outlet fluidically connected to a particulate discharge duct; a flue duct inlet oriented upstream of the at least one primary collection hopper field; a flue duct outlet oriented downstream of the primary collection hopper field; wherein the gas producer is fluidically connected to the primary particulate collector unit by a flue duct; and a particulate recirculation duct fluidically connected at a first end to the primary collection hopper and/or the particulate discharge duct, and fluidically connected at a second end to the flue duct upstream of the primary particulate collector unit.

In a soot blower, a heat transfer tube of a heat exchanger is arranged inside a pressure vessel, and gas for cleaning is injected toward the heat transfer tube from an injection pipe movable into and out of the pressure vessel. The soot blower includes a cylindrical casing provided to surround an insertion hole on the pressure vessel side into which the injection pipe is inserted, to extend outside the pressure vessel, the injection pipe being inserted into an inside of the casing; a support part provided inside the casing to guide movement of the injection pipe and to ensure airtightness between the casing and the injection pipe; and a gas supplying device provided immediately close to the support part to generate a jet stream of gas in a portion of the injection pipe that projects to the pressure vessel side.

A method for cooling solid residues of a combustion process, which are deposited onto the conveying surface of a conveyor belt of a conveying device and are conveyed in the direction of a solid residue outlet, wherein during conveying heat is transferred from the solid residues to a gaseous coolant. The method is characterized in that the conveyor belt is acted upon by coolant only on its side oriented away from the conveying surface, the conveyor belt is essentially impermeable to the coolant and at least part of the coolant heated by contact with the conveyor belt is extracted on that side oriented away from the conveying surface.

A method for cooling solid residues of a combustion process, which are deposited onto the conveying surface of a conveyor belt of a conveying device and are conveyed in the direction of a solid residue outlet, wherein during conveying heat is transferred from the solid residues to a gaseous coolant. The method is characterized in that the conveyor belt is acted upon by coolant only on its side oriented away from the conveying surface, the conveyor belt is essentially impermeable to the coolant and at least part of the coolant heated by contact with the conveyor belt is extracted on that side oriented away from the conveying surface.

A boiler ash remover based on a combined flow includes a frequency-adjustable acoustic flow generator, a fixing bracket, a compressed air source, a three-way air-source electric-control valve, an air jet generator, an acoustic-jet combined transmission tube, an acoustic jet intelligent control system, and a scale measurement and control sensor. The compressed air source is connected to an inlet end of the three-way air-source electric-control valve. An outlet end of the three-way air-source electric-control valve is connected to the frequency-adjustable acoustic flow generator and an air source inlet end of the air jet generator respectively. An acoustic flow outlet end of the frequency-adjustable acoustic flow generator is connected to an inlet end of the acoustic-jet combined transmission tube. An outlet end of the acoustic-jet combined transmission tube and a jet outlet end of the air jet generator are both disposed opposite to an external heat exchange component by means of the fixing bracket. The area of an acoustic flow transmission orifice at the outlet end of the acoustic-jet combined transmission tube covers that of a jet injection orifice at the jet outlet end of the air jet generator. The acoustic jet intelligent control system is connected to an electric control device of the three-way air-source electric-control valve and the scale measurement and control sensor respectively. The scale measurement and control sensor is disposed on the external heat exchange component. The boiler ash remover has the advantages of combining a frequency-adjustable acoustic flow with an air jet and implementing acoustic jet intelligent control, and has a desirable effect of removal of scales in a hearth or a flue gas heat exchanger.

A method for efficiently conveying impurities in a pressurized fluidized incinerator system is provided. Cleaning gas is supplied to an upper valve, and thereafter, the upper valve is driven so as to communicate an upper discharge device and a tank. The upper discharge device is driven so as to convey the impurities from the dust collector to the tank, and thereafter, the upper discharge device is stopped and the upper valve is driven so as not to communicate the upper discharge device and the tank. Thereafter, the supply of the cleaning gas to the upper valve is stopped.

A method for efficiently conveying impurities in a pressurized fluidized incinerator system is provided. Cleaning gas is supplied to an upper valve, and thereafter, the upper valve is driven so as to communicate an upper discharge device and a tank. The upper discharge device is driven so as to convey the impurities from the dust collector to the tank, and thereafter, the upper discharge device is stopped and the upper valve is driven so as not to communicate the upper discharge device and the tank. Thereafter, the supply of the cleaning gas to the upper valve is stopped.

The present invention is directed to additives for coal-fired furnaces, particularly furnaces using a layer of slag to capture coal particles for combustion. The additive(s) include iron, mineralizer(s), handling aid(s), flow aid(s), and/or abrasive material(s). The iron and mineralizers can lower the melting temperature of ash in low-iron, high alkali coals, leading to improved furnace performance.