The invention is in the technical field of bubbling fluidized bed combustion and relates to the use of ilmenite particles with an average particle size <dp> between 0.1 mm and 1.8 mm as bed material for a bubbling fluidized bed (BFB) boiler with an excess air ratio () below 1.3 and to a method for operating a bubbling fluidized bed (BFB) boiler, comprising carrying out the combustion process with a bubbling fluidized bed comprising ilmenite particles as defined in any one of claims 1 and 4-5; and setting the excess air ratio () to a value below 1.3.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

Methods, devices and systems for processing of solid materials, particularly fuel material solids such as carbonaceous fuel solids such as of granular form, to provide or result in an even distribution of the solid material. Hoppers are provided with plurality of outlet orifices, each of the outlet orifices adapted to flow therethrough a combination of gas and the solid material to pneumatically convey the solid material to a distribution manifold. The distribution manifold includes a plurality of tubes with each tube having a plurality of exit orifices wherein each exit orifice passes an equal portion of the combination of the gas and the solid material.

Methods, devices and systems for processing of solid materials, particularly fuel material solids such as carbonaceous fuel solids such as of granular form, to provide or result in an even distribution of the solid material. Hoppers are provided with plurality of outlet orifices, each of the outlet orifices adapted to flow therethrough a combination of gas and the solid material to pneumatically convey the solid material to a distribution manifold. The distribution manifold includes a plurality of tubes with each tube having a plurality of exit orifices wherein each exit orifice passes an equal portion of the combination of the gas and the solid material.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. A Stirling engine along with cooling system and engine control box is integrated with the SFBC chamber to produce electricity from the waste combustion process. Residual heat in the flue gas may be captured after the combustion chamber and directed to a fuel feeder to first dry the biomass. System exhaust is directed to a twisted tube-based shell and tube heat exchanger (STHE) and may produce hot water for space heating.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. A Stirling engine along with cooling system and engine control box is integrated with the SFBC chamber to produce electricity from the waste combustion process. Residual heat in the flue gas may be captured after the combustion chamber and directed to a fuel feeder to first dry the biomass. System exhaust is directed to a twisted tube-based shell and tube heat exchanger (STHE) and may produce hot water for space heating.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. The system exhaust is directed to a pollutant control unit and heat exchanger, where the captured heat may be put to useful work.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. The system exhaust is directed to a pollutant control unit and heat exchanger, where the captured heat may be put to useful work.

A circular fluidizing bed combustion system with uniform airflow distributing device is provided. The system comprises a fluidizing bed and a uniform airflow distributing device. The fluidizing bed is comprised of a fluidizing bed boiler body, an airflow distributing plate and a plurality of air caps, wherein, the airflow distributing plate is provided inside the fluidizing bed boiler body and divides the inner space of the fluidizing bed boiler body into a fluidizing chamber which is located in the upper portion of the boiler body and an air chamber which is located in the lower portion of the boiler body, and the plurality of air caps are arranged on the airflow distributing plate for injecting the fluidizing air into the fluidizing chamber. The inner space of the air chamber is divided into a distributing chamber that is located under the airflow distributing plate and an air inlet chamber that is located on one side of the distributing chamber by means of a perforated plate. The distributing chamber is comprised of a front wall, two side walls, a top wall that extends upwards obliquely from the upside of the front wall, and a bottom wall extends downwards obliquely from the downside of the front wall. A first guide plate, a second guide plate and a third guide plate are installed in the distributing chamber. This system makes the flow of the fluidizing air entered into the fluidizing chamber through each air cap uniform, and enhances the combusting efficiency of the coal powder in the fluidizing chamber.