Abstract: A method for improving pulp mill steam cycle efficiency includes the steps of providing at least one deaerator tank having a first pressure, and lowering the pressure of said deaerator tank to a second pressure. Feedwater is supplied to a pre-economizer, where it is heated. The water is then delivered to at least one feedwater heater, where it is heated. The water is then delivered to an economizer. By this method boiler steam rate is increased while boiler efficiency is maintained and turbine extraction for deaerator and feedwater heating is minimized.

Abstract: An enhanced steam cycle utilizing a dual pressure recovery boiler with reheat. A dual pressure designed recovery boiler furnace is provided with a lower furnace and an upper furnace. The lower furnace is operated at a lower temperature to prevent or reduce corrosion of the lower furnace wall tubes. The lower furnace can be either a low pressure natural circulation steam generating (drum) system or economizer. The upper furnace operates as a high pressure natural circulation steam generating (drum) system, or as a once-through supercritical steam generating system at higher temperatures and pressures permitting implementation of higher efficiency reheat steam cycles.

Abstract: An integrated water coil air heater and economizer arrangement for a boiler has a feedwater inlet for supplying feedwater to the boiler, and conduits and a valve for splitting the feedwater from the inlet into a first partial lower temperature, lower mass flow stream, and a second partial higher temperature, higher flow stream. A water coil air heater for passage of air to be heated for the boiler contains at least one heat transfer loop in heat transfer relationship with the air, the heat transfer loop of the water coil air heater being connected to receive the first partial stream. An economizer for passage of flue gas to be cooled for the boiler contains at least one heat transfer loop in heat transfer relationship with the flue gas, the heat transfer loop of the economizer being connected to the heat transfer loop of the water coil air heater for receiving the first partial stream from the water coil air heater.

Abstract: A method for improving pulp mill steam cycle efficiency includes the steps of providing at least one deaerator tank having a first pressure, and lowering the pressure of said deaerator tank to a second pressure. Feedwater is supplied to a pre-economizer, where it is heated. The water is then delivered to at least one feedwater heater, where it is heated. The water is then delivered to an economizer. By this method boiler steam rate is increased while boiler efficiency is maintained and turbine extraction for deaerator and feedwater heating is minimized.

Abstract: A combustion apparatus capable of firing biomass fuel including a burner assembly which includes a biomass nozzle concentrically surrounded by a core air zone and extending axially along the length of the core air zone, the burner assembly residing within a windbox, the windbox being attached to a furnace of a boiler, and the burner assembly being connected to the furnace by a burner throat, through which air and fuel supplied to the burner assembly are emitted into the furnace.

Abstract: An integrated water coil air heater and economizer arrangement for a boiler has a feedwater inlet for supplying feedwater to the boiler, and conduits and a valve for splitting the feedwater from the inlet into a first partial lower temperature, lower mass flow stream, and a second partial higher temperature, higher flow stream. A water coil air heater for passage of air to be heated for the boiler contains at least one heat transfer loop in heat transfer relationship with the air, the heat transfer loop of the water coil air heater being connected to receive the first partial stream. An economizer for passage of flue gas to be cooled for the boiler contains at least one heat transfer loop in heat transfer relationship with the flue gas, the heat transfer loop of the economizer being connected to the heat transfer loop of the water coil air heater for receiving the first partial stream from the water coil air heater.

Abstract: An enhanced steam cycle utilizing a dual pressure recovery boiler with reheat allows a large increase in electrical generation with various turbine cycles while overcoming traditional lower furnace material limitations. A dual pressure designed recovery boiler furnace is provided with a lower furnace and an upper furnace. The lower furnace is operated at a lower temperature to prevent or reduce corrosion of the lower furnace wall tubes caused by the reducing environment. The lower furnace can be either a low pressure natural circulation steam generating (drum) system or economizer. Unlike the lower furnace, the upper furnace is not exposed to a reducing environment and is therefore not as susceptible to severe corrosion rates. The upper furnace is operated at higher temperatures and pressures which permit implementation of higher efficiency reheat steam cycles.

Abstract: A system and method for producing product gas using residual waste liquor is described with a gasifier reactor having a fluidized bed located therein. The gasifier reactor is heated to a predetermined temperature range with either an external heater or a second fluidized bed located at a position below the first fluidized bed. A heat exchanger may be positioned in the first fluidized bed and/or the second fluidized bed for indirectly heating the respective fluidized beds. Condensing heat exchanger means recovers heat from the product gas and condenses an acid gas therefrom for recycling the chemicals. A reagent is sprayed in the condensing heat exchanger means to clean the product gas. Pressurization allows the cleaned product gas to be directly fired in a turbine.

Abstract: A system and method for producing product gas using residual waste liquor is described with a gasifier reactor having a fluidized bed located therein. The gasifier reactor is heated to a predetermined temperature range with either an external heater or a second fluidized bed located at a position below the first fluidized bed. A heat exchanger may be positioned in the first fluidized bed and/or the second fluidized bed for indirectly heating the respective fluidized beds. Condensing heat exchanger means recovers heat from the product gas and condenses an acid gas therefrom for recycling the chemicals. A reagent is sprayed in the condensing heat exchanger means to clean the product gas. Pressurization allows the cleaned product gas to be directly fired in a turbine.

Abstract: A system and method for producing product gas using residual waste liquor is described with a gasifier reactor having a fluidized bed located therein. The gasifier reactor is heated to a predetermined temperature range with either an external heater or a second fluidized bed located at a position below the first fluidized bed. A heat exchanger may be positioned in the first fluidized bed and/or the second fluidized bed for indirectly heating the respective fluidized beds. Condensing heat exchanger means recovers heat from the product gas and condenses an acid gas therefrom for recycling the chemicals. A reagent is sprayed in the condensing heat exchanger means to clean the product gas. Pressurization allows the cleaned product gas to be directly fired in a turbine.