Abstract: The invention relates to a process for manufacturing clinker from a raw mix, implementing the following: preheating of the raw mix by combustion flue gases; precalcination of the raw mix; and calcination of the precalcined raw mix in a rotary kiln, in which process the precalcination and the calcination in the rotary kiln produce combustion flue gases that contain CO2, in which the combustion flue gases created by the precalcination undergo a CO2-removal treatment without said flue gases mixing with the combustion flue gases created by the calcination in the rotary kiln.

Abstract: The invention relates to a method for calcination of a material in which said material is heated by contact with a heat source essentially generated by means of a flame produced with at least one flow of fuel and primary air and a flow of secondary air, the flame comprising a first combustion zone with a temperature below 1500° C. and a second combustion zone with a temperature above 1500° C., where at least one flow of at least one inert gas is injected into the flame at the beginning of the second combustion zone and/or at least one flow of oxygen or a gas enriched in oxygen is injected into the second combustion zone.

Abstract: The invention relates to a process for manufacturing clinker from a raw mix, implementing the following: preheating of the raw mix by combustion flue gases; precalcination of the raw mix; and calcination of the precalcined raw mix in a rotary kiln, in which process the precalcination and the calcination in the rotary kiln produce combustion flue gases that contain CO2, in which the combustion flue gases created by the precalcination undergo a CO2-removal treatment without said flue gases mixing with the combustion flue gases created by the calcination in the rotary kiln.

Abstract: The invention relates to a method for calcination of a material in which said material is heated by contact with a heat source essentially generated by means of a flame produced with at least one flow of fuel and primary air and a flow of secondary air, the flame comprising a first combustion zone with a temperature below 1500° C. and a second combustion zone with a temperature above 1500° C., where at least one flow of at least one inert gas is injected into the flame at the beginning of the second combustion zone and/or at least one flow of oxygen or a gas enriched in oxygen is injected into the second combustion zone.

Abstract: A steam-generating combustion system includes an oxygen enriched gas provided as at least part of an oxidant stream. A combustion chamber receives and combusts a fuel in the oxidant stream and generate steam. The combustion chamber generates flue gas having a flue gas volume which is smaller than a volume of flue gas generated by the combustion chamber when operated with air as the oxidant stream. A flue gas pollutant control system receives the flue gas from the combustion chamber and reduces at least one of particulate matter, SOx, NOx, and mercury. The reduction in flue gas volume allows the implementation of much smaller pollutant control equipment, since the size of the pollutant control units is mainly based on the volume or mass flow rate of flue gas to be treated. Moreover, the system including oxygen-enriched gas in the oxidant will lead to concentrated levels of the pollutants in the flue gas.

Abstract: Methods for optimizing emission levels from combustion operations, which include a system and process for optimizing levels of NOx and CO during fuel combustion including supplying flows of fuel (which is predetermined) and main oxidant to a burner. Oscillating combustion is generated by oscillating the fuel flow with an oscillating valve and combusting the oscillating fuel with the main oxidant adjacent the burner to produce combustion products. A post-combustion oxidant is injected into the combustion products where it is combusted with the combustion products. A controller is operatively associated with control units for controlling the main oxidant and post-combustion oxidant flow rates and the oscillating valve.

Abstract: An improved process for burning solid fuel particles in a combustion chamber and creating a flue gas is disclosed. The method comprises creating a fuel gas stream by mixing the solid fuel particles with a conveying gas, transporting the fuel gas stream through a fuel duct terminating at the combustion chamber at a fuel exit plane and injecting an oxygen stream through an injection device into said fuel gas at an oxygen injection location selected to create a mixing zone to mix the oxygen stream and the fuel gas stream immediately prior to or coincident with combustion of the fuel. Operating parameters of the process can be varied to optimally reduce NOx emissions.

Abstract: An air separation unit separates air into an oxygen-rich and oxygen-deficient gas. Fuel gas and the oxygen-rich gas are preheated at heat exchangers through which hot flue gas flows. Combustion of the preheated fuel and oxygen-rich gases result in the hot flue gas. The hot flue gas is cooled at the heat exchangers and flows through a waste heat boiler. Water and/or steam flowing through the waste heat boiler absorbs energy from the cooled flue gas thereby producing heated steam. The heated steam flows through a turbine to produce power. The power is transferred to the air separation unit, thus reducing a power requirement of the air separation unit needed to separate the air.

Abstract: A method and apparatus for monitoring the flue gases of a furnace combustion process is disclosed. A by-pass circuit that communicates a sample of flue gases to be monitored from a furnace, through a measurement chamber and back to the furnace or furnace exhaust duct is provided. The by-pass circuit has a gas sampling probe with a fume inlet opening, the probe being positioned for withdrawing the sample to be monitored and transmitting it through the by-pass circuit. A measurement device is positioned in the measurement chamber and comprises an in situ optical device which provides real-time measurement of targeted flue gas species concentrations.

Abstract: A steam-generating combustion system includes an oxygen enriched gas provided as at least part of an oxidant stream. A combustion chamber receives and combusts a fuel in the oxidant stream and generate steam. The combustion chamber generates flue gas having a flue gas volume which is smaller than a volume of flue gas generated by the combustion chamber when operated with air as the oxidant stream. A flue gas pollutant control system receives the flue gas from the combustion chamber and reduces at least one of particulate matter, SOx, NOx, and mercury. The reduction in flue gas volume allows the implementation of much smaller pollutant control equipment, since the size of the pollutant control units is mainly based on the volume or mass flow rate of flue gas to be treated. Moreover, the system including oxygen-enriched gas in the oxidant will lead to concentrated levels of the pollutants in the flue gas.

Abstract: Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which oxygen-enriched air flows and exchanges heat indirectly with flue gas, creating a preheated oxygen-enriched air stream. The apparatus further comprises a boiler having a radiant section and a convection section, and other heat transfer units adapted to handle reduced flue gas flow rate and higher temperature flue gases than comparable air/fuel combustion boilers, thus allowing a smaller heat transfer surface area, a more compact design and a higher efficiency.

Abstract: A steam-generating combustion system includes an oxygen enriched gas provided as at least part of an oxidant stream. A combustion chamber receives and combusts a fuel in the oxidant stream and generate steam. The combustion chamber generates flue gas having a flue gas volume which is smaller than a volume of flue gas generated by the combustion chamber when operated with air as the oxidant stream. A flue gas pollutant control system receives the flue gas from the combustion chamber and reduces at least one of particulate matter, SOx, NOx, and mercury. The reduction in flue gas volume allows the implementation of much smaller pollutant control equipment, since the size of the pollutant control units is mainly based on the volume or mass flow rate of flue gas to be treated. Moreover, the system including oxygen-enriched gas in the oxidant will lead to concentrated levels of the pollutants in the flue gas.

Abstract: An improved process for burning a fuel to produce a flue gas is disclosed. The fuel is burned in a main combustion zone in the presence of a main combustion oxidant to produce combustion products. The combustion products are mixed in a post-combustion zone positioned downstream from the main combustion zone. The post-combustion zone is provided with a recirculation zone positioned proximate to the main combustion zone and an injection zone positioned downstream from the recirculation zone. An post-combustion oxidant is injected into the combustion products in the injection zone. At least one of (a) the residence time of the combustion products in the post-combustion zone, (b) the temperature range of the combustion products contained within the injection zone and (c) the oxygen content of the oxidant is controlled to optimize the level of CO and NOx in the flue gas.

Abstract: An improved process for burning a fuel to produce a flue gas is disclosed. The fuel is burned in a main combustion zone in the presence of a main combustion oxidant to produce combustion products. The combustion products are mixed in a post-combustion zone positioned downstream from the main combustion zone. The post-combustion zone is provided with a recirculation zone positioned proximate to the main combustion zone and an injection zone positioned downstream from the recirculation zone. An post-combustion oxidant is injected into the combustion products in the injection zone. At least one of (a) the residence time of the combustion products in the post-combustion zone, (b) the temperature range of the combustion products contained within the injection zone and (c) the oxygen content of the oxidant is controlled to optimize the level of CO and NOx in the flue gas.

Abstract: Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which oxygen-enriched air flows and exchanges heat indirectly with flue gas, creating a preheated oxygen-enriched air stream. The apparatus further comprises a boiler having a radiant section and a convection section, and other heat transfer units adapted to handle reduced flue gas flow rate and higher temperature flue gases than comparable air/fuel combustion boilers, thus allowing a smaller heat transfer surface area, a more compact design and a higher efficiency.

Abstract: An improved process for burning solid fuel particles in a combustion chamber and creating a flue gas is disclosed. The method comprises creating a fuel gas stream by mixing the solid fuel particles with a conveying gas, transporting the fuel gas stream through a fuel duct terminating at the combustion chamber at a fuel exit plane and injecting an oxygen stream through an injection device into said fuel gas at an oxygen injection location selected to create a mixing zone to mix the oxygen stream and the fuel gas stream immediately prior to or coincident with combustion of the fuel. Operating parameters of the process can be varied to optimally reduce NOx emissions.

Abstract: A steam-generating combustion system includes an oxygen enriched gas provided as at least part of an oxidant stream. A combustion chamber receives and combusts a fuel in the oxidant stream and generate steam. The combustion chamber generates flue gas having a flue gas volume which is smaller than a volume of flue gas generated by the combustion chamber when operated with air as the oxidant stream. A flue gas pollutant control system receives the flue gas from the combustion chamber and reduces at least one of particulate matter, SOx, NOx, and mercury. The reduction in flue gas volume allows the implementation of much smaller pollutant control equipment, since the size of the pollutant control units is mainly based on the volume or mass flow rate of flue gas to be treated. Moreover, the system including oxygen-enriched gas in the oxidant will lead to concentrated levels of the pollutants in the flue gas.

Abstract: An air separation unit separates air into an oxygen-rich and oxygen-deficient gas. Fuel gas and the oxygen-rich gas are preheated at heat exchangers through which hot flue gas flows. Combustion of the preheated fuel and oxygen-rich gases result in the hot flue gas. The hot flue gas is cooled at the heat exchangers and flows through a waste heat boiler. Water and/or steam flowing through the waste heat boiler absorbs energy from the cooled flue gas thereby producing heated steam. The heated steam flows through a turbine to produce power. The power is transferred to the air separation unit, thus reducing a power requirement of the air separation unit needed to separate the air.

Abstract: Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which oxygen-enriched air flows and exchanges heat indirectly with flue gas, creating a preheated oxygen-enriched air stream. The apparatus further comprises a boiler having a radiant section and a convection section, and other heat transfer units adapted to handle reduced flue gas flow rate and higher temperature flue gases than comparable air/fuel combustion boilers, thus allowing a smaller heat transfer surface area, a more compact design and a higher efficiency.

Abstract: A method and apparatus for monitoring the flue gases of a furnace combustion process is disclosed. A by-pass circuit that communicates a sample of flue gases to be monitored from a furnace, through a measurement chamber and back to the furnace or furnace exhaust duct is provided. The by-pass circuit has a gas sampling probe with a fume inlet opening, the probe being positioned for withdrawing the sample to be monitored and transmitting it through the by-pass circuit. A measurement device is positioned in the measurement chamber and comprises an in situ optical device which provides real-time measurement of targeted flue gas species concentrations.