A method and a boiler for burning a liquid or gaseous fuel. The boiler comprises a boiler housing with a cylindrical heat exchanger arranged therein and has slot-like pass-through openings for the combustion gases and has a flame tube. A flame-deflecting part for deflecting the combustion gases at a right angle is provided at an axial distance from the flame tube. The flame tube contains a baffle plate with a faceplate through which combustion air is fed into the flame tube. A blower ensures the supply of combustion air into the combustion chamber. Blower pressure is so that a differential pressure zone with a differential pressure of at least 0.25 mbar is generated between the flame tube and the heat exchanger, downstream of the faceplate at full load of the burner in relation to the pressure in the combustion chamber in the region of the recirculation slots.

A gas outlet monitoring system for a boiler system includes a gas probe(s) with a plurality of gas sensing locations wherein each location measures a plurality of parameters of the gas flow, such a oxygen concentration and temperature. The multi-sensor probe includes a tubular lance and a plurality of sensor pods spaced along the lance. Each sensor pod has an oxygen sensor disposed in a first port, and a first temperature sensor disposed in a second port. An enclosure is disposed at one end of the tubular lance. The enclosure has a respective pressure sensor for each oxygen sensor port. A plurality of first tubes passes through the lance between the enclosure and the first port of a respective sensor pod to provide a gas to the respective first port for the purpose of providing cleaning air. A plurality of second tubes passes through the lance between the enclosure and the first port of a respective sensor pod to provide fluid communication between gas in the respective first port and the respective pressure sensor. One pressure sensor is provided for each oxygen sensor.

A heater device including at least one control and/or regulating unit, which is provided to set an air ratio of a combustion process to a setpoint air ratio. It is provided that the control and/or regulating unit is provided to ascertain a power correction factor in at least one operating state and take it into consideration in the setting of the air ratio.

A radiant burner and method are disclosed. The radiant burner is for treating an effluent gas stream from a manufacturing process tool and comprises: a combustion chamber having a porous sleeve through which combustion materials pass for combustion proximate to a combustion surface of the porous sleeve; a combustion characteristic monitor operable to determine combustion performance of the radiant burner by monitoring infra-red radiation emitted from the combustion surface; and a radiant burner controller operable to control operation of the radiant burner in dependence upon combustion performance determined by the combustion characteristic monitor. Accordingly, aspects recognize that if a burner is suffering from an excessive flow of air the burner pad or combustion surface will typically cool, which results in an increase in unwanted emissions in the exhaust produced by a radiant burner. The cooling also results in a reduction in infrared radiation determined by the combustion surface. The hydrogen flame of the radiant burner and the hydrocarbon flame of the burner pilot typically do not emit infrared radiation and thus a change in infra-red an radiation, for example, intensity, quantity or frequency, emitted by the combustion surface of the radiant burner can be used to diagnose an overflow of cold gas, typically air, in the combustion mixture fed into the system, for example, the combustion chamber. Once diagnosed appropriate ameliorative steps may be taken and, for example, the burner control logic may be operable to compensate by reducing air flow into the burner.

A system and method for calibrating flame current in a furnace is disclosed. The method includes initiating combustion within a combustion chamber by allowing flow of the fuel mixture to the combustion chamber; receiving, from a sensor, signals indicative of a flow rate of the air to the combustion chamber; receiving, from a flame rod sensor, signals indicative of a flame current of the combustion chamber; varying a flow rate of the air to the combustion chamber; receiving, from the flame rod sensor, responsive to varying flow rate of the air to the combustion chamber, signals indicative of a change in the flame current of the combustion chamber; and determining, based on varying flow rate of the air to the combustion chamber, and the change in flame current of the combustion chamber, a correlation between the flow rate of the air, and the flame current of the combustion chamber.

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.

A combustion system includes a combustion chamber, a plurality of fuel introduction locations in the combustion chamber where fuel and air are provided to the combustion chamber for combustion, a fluid flow control device associated with each fuel introduction location, each fluid flow control device being controllable to vary an amount of the air supplied to each fuel introduction location, a plurality of sensing devices configured to monitor a plurality of operational parameters of the combustion system, and a control unit configured to control each fluid flow control device to control the amount of air supplied at each fuel introduction location independent of the amount of air supplied at the other fuel introduction locations, and to control the amount of air provided to all other air introduction locations, in dependence upon at least one of the plurality of operational parameters to minimize excess air provided to the combustion chamber.

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.

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.