A system for converting fuel may include a first moving bed reactor, a second reactor, and a non-mechanical valve. The first moving bed reactor may include at least one tapered section and multiple injection gas ports. The multiple injection gas ports may be configured to deliver a fuel to the first moving bed reactor. The first moving bed reactor may be configured to reduce an oxygen carrying material with a fuel by defining a countercurrent flowpath for the fuel relative to the oxygen carrying material. The second reactor may communicate with the first moving bed reactor and may be operable to receive an oxygen source. The second reactor may be configured to regenerate the reduced oxygen carrying material by oxidation.

A system for converting fuel may include a first moving bed reactor, a second reactor, and a non-mechanical valve. The first moving bed reactor may include at least one tapered section and multiple injection gas ports. The multiple injection gas ports may be configured to deliver a fuel to the first moving bed reactor. The first moving bed reactor may be configured to reduce an oxygen carrying material with a fuel by defining a countercurrent flowpath for the fuel relative to the oxygen carrying material. The second reactor may communicate with the first moving bed reactor and may be operable to receive an oxygen source. The second reactor may be configured to regenerate the reduced oxygen carrying material by oxidation.

A method of operating an oxycombustion circulating fluidized bed (CFB) boiler that includes a furnace having a grid at its bottom section, a solid material separator connected to an upper part of the furnace, and an external solid material handling system. Oxidant gas is introduced into the CFB boiler through the grid as fluidizing gas, the fluidizing gas including recirculating flue gas. Fuel material is introduced into the circulating fluidized bed. A sulfur reducing agent including CaCO.sub.3 is introduced into the circulating fluidized bed. Solid material is circulated out of the furnace and provides an external circulation of solid material via the external solid material handling system. The solid material is fluidized in the external solid material handling system by introducing a fluidizing medium including recirculating flue gas into the handling system. A predetermined amount of steam is introduced into the handling system as a component of the fluidizing medium.

A method of operating an oxycombustion circulating fluidized bed (CFB) boiler that includes a furnace having a grid at its bottom section, a solid material separator connected to an upper part of the furnace, and an external solid material handling system. Oxidant gas is introduced into the CFB boiler through the grid as fluidizing gas, the fluidizing gas including recirculating flue gas. Fuel material is introduced into the circulating fluidized bed. A sulfur reducing agent including CaCO.sub.3 is introduced into the circulating fluidized bed. Solid material is circulated out of the furnace and provides an external circulation of solid material via the external solid material handling system. The solid material is fluidized in the external solid material handling system by introducing a fluidizing medium including recirculating flue gas into the handling system. A predetermined amount of steam is introduced into the handling system as a component of the fluidizing medium.

A sealpot for a combustion power plant includes a downcomer standpipe which receives solids of the combustion power plant, a bed including a first end and a second opposite end, the first end connected to the downcomer standpipe, a discharge standpipe disposed at the second opposite end of the bed, and an orifice plate disposed between the bed and the discharge standpipe separating the discharge standpipe from the bed. The orifice plate includes apertures disposed at a height above the bed which allow transport of fluidized solids and gas through the orifice plate.

The present invention is related to a circulating fluidized bed gasification or combustion system (1) using coal or biomass as raw material and comprising a combustion/gasification reactor (2); a cyclone (3) which is in connection with the reactor (2) in order that solid particles are separated from gas flow; a downcomer (4) which is in connection with the reactor (2) and the cyclone (3), extends along the reactor (2), and enables solid particles captured by the cyclone (3) to be sent to the combustion/gasification reactor (2) again; a distributing plate (5) which is in connection with the reactor (2) and performs primary gas supply to the system (1) homogeneously; at least one conduit which is positioned parallel to the downcomer (4); an ejector (7) which is positioned on the downcomer (4) vertically, comprises at least one nozzle (6) spraying pressurized gas towards the reactor (2).

Disclosed herein is a solids flow control valve comprising a standpipe; a shoe; and a transport pipe; wherein the standpipe is in operative communication with the shoe and lies upstream of the shoe; the standpipe comprising a first end and a second end, where the first end is in contact with a source that contains disposable solids and the second end is in fluid contact with the shoe; the shoe being operative to restrict the flow of the disposable solids; the transport pipe being disposed downstream of the shoe to receive and transport the solids from the shoe.

Disclosed herein is a solids flow control valve comprising a standpipe; a shoe; and a transport pipe; wherein the standpipe is in operative communication with the shoe and lies upstream of the shoe; the standpipe comprising a first end and a second end, where the first end is in contact with a source that contains disposable solids and the second end is in fluid contact with the shoe; the shoe being operative to restrict the flow of the disposable solids; the transport pipe being disposed downstream of the shoe to receive and transport the solids from the shoe.

A method of monitoring circulation of solid material in a circulating fluidized bed reactor including a reaction chamber, at least one solid material separator, and a return path between the separator and the chamber. The method includes selecting process variables of the process of circulating of solid material in the return path, and selecting performance indicators of the process of circulation of solid material amongst the selected process variables for each performance indicator of the process of circulation of material, creating a multivariate model for each performance indicator, using history data of the process variables and the performance indicators, determining a modelled value of the performance indicators, by applying current measured values of the process variables to the multivariate model, and comparing the modelled value of each performance indicator to a respective measured value and inspecting a presence of an anomaly between the modelled value and the respective measured value.

A method of monitoring circulation of solid material in a circulating fluidized bed reactor including a reaction chamber, at least one solid material separator, and a return path between the separator and the chamber. The method includes selecting process variables of the process of circulating of solid material in the return path, and selecting performance indicators of the process of circulation of solid material amongst the selected process variables for each performance indicator of the process of circulation of material, creating a multivariate model for each performance indicator, using history data of the process variables and the performance indicators, determining a modelled value of the performance indicators, by applying current measured values of the process variables to the multivariate model, and comparing the modelled value of each performance indicator to a respective measured value and inspecting a presence of an anomaly between the modelled value and the respective measured value.