A fuel nozzle apparatus can include a nozzle that functions with two or more modes of operation with respect to a group of fuels, and an air shroud fixed over the nozzle. The air shroud blocks air through the nozzle or allows air through the nozzle in a predefined pattern. When a position of the air shroud is varied, the amount of the air and the location of the air into the nozzle is changed to facilitate the two or more modes of operation with respect to the group of fuels.

The invention is in the field of boiler control and relates to a control method for the operation of a combustion boiler, comprising providing a predetermined upper limit (VF,max) for the flue gas velocity in at least one location of the boiler, monitoring the flue gas velocity (VF) during the combustion of fuel in said at least one location of the boiler, comparing the flue gas velocity (VF) with the predetermined upper limit (VF,max); decreasing the thermal load of the boiler if the flue gas velocity exceeds the predetermined upper limit (VF,max). The invention also relates to a control system configured to execute the control method.

The invention relates to a method for operating a fluidized bed boiler, comprising: a) setting the ratio of secondary oxygen containing gas to primary oxygen containing fluidizing gas to a value ranging from 0.0 to 0.8; b) carrying out the combustion of fuel with a fluidized bed comprising ilmenite particle; and to a fluidized bed boiler.

A method for conducting combustion in a fluidized bed furnace, in particular having a sand bed, according to which a flow of primary combustion air is blown through the bed, the fuel consisting in particular of organic waste, or of municipal waste, or of sludge from purifying stations, it being possible to inject secondary air (5a) into the space (5) in the furnace located above the bed; in order to limit the production of nitrogen oxides NOx and nitrous oxide N2O: the nitrous oxide N2O and nitrogen oxide NOx content of the fumes at the outlet of the furnace are measured (12, 20); the temperature of the fluidized bed is controlled to keep it at the highest admissible value at which the production of nitrous oxide N2O is substantially reduced, while the production of nitrogen oxides NOx is not substantially increased; and the excess air in the fluidized bed is controlled to keep it at the lowest admissible value at which the production of nitrogen oxides NOx is reduced without adversely affecting the combustion and the temperature of the bed.

An apparatus and method for operating a gas-fired burner on a liquid fuel. The apparatus integrates a catalytic liquid fuel reformer with a flame burner designed for operation on a gaseous fuel of high Wobbe Index, e.g., natural gas. The method involves reacting a mixture of a liquid fuel and oxidant in a catalytic reformer to obtain a gaseous reformate having a low Wobbe Index; and thereafter combusting the gaseous reformate, optionally augmented with liquid co-fuel and oxidant, in the gas-fired burner under diffusion flame conditions. The invention allows commercial gas-fired appliances, such as stoves, ovens, ranges, grills, griddles, stock pot burners, clothes dryers, hot water heaters, and boilers to be operated on a liquid fuel, which offers advantages in logistics and camp operations.

A method of starting an auto-ignition gas torch includes increasing a flow of oxygen above zero and increasing a flow of fuel gas to a level lower than the flow of oxygen for improved start reliability. In one form, the flow of oxygen is from about two times to about six times higher than the flow of fuel gas.

A method of operation of a thermal power plant having an air separation system with a plurality of air storage unit (ASU) compressors and a liquid oxygen/liquid air (LOX/LA) storage facility for oxyfuel firing of fossil fuel and a power plant having a control system to perform the same are described. The method is characterized by the step of controlling the net power output of the plant in response to short term variations in grid demanded net plant output by dynamically adjusting the works power of the ASU compressors preferably in conjunction with co-ordinated changes in firing demand. The method is in particular a method to produce an improved primary and secondary response to transient changes in grid demand and to provide accurate response to load dispatch ramps.

A gas burner for use in low-oxygen environments in which the oxygen concentration is insufficient to ensure complete combustion. The burner includes a central air supply that is annularly surrounded by a gas supply, thereby preventing the fuel from burning out with a delay in places where burn-out is detrimental to a system or plant.

A combined heat exchanger including a flue gas cooler heat-transfer unit supplied with cooling fluid by a supply pump and an upstream GGH heat-transfer unit for circulation of circulating fluid with a downstream GGH by a circulation pump is arranged at an outlet of a gas air heater for heat exchange of flue gas from a boiler body for oxyfuel combustion with recirculation flue gases. A low-low temperature ESP is arranged at an outlet of the combined heat exchanger. A heat-exchange-duty adjustment device is arranged to regulate heats exchanged in the heat-transfer units in the heat exchanger such that at least flue gas temperature at the inlet of the low-low temperature ESP is kept to an inlet set temperature.

An impinging-type temperature uniformity device includes an outer case portion; and a temperature uniformizer provided in the outer case portion, spaced apart inwardly from an inner surface of the outer case portion and connected to the outer case portion, wherein the temperature uniformizer includes: a head portion provided in the outer case portion; and a body portion spaced apart inwardly from the inner surface of the outer case portion and including at least one through-hole.