Abstract: A system and method for reducing emissions from a boiler. A boiler generally has a combustion area. The system further includes a fuel pipe for delivering fuel. The system further includes a conduit. A bore extends through the conduit. The bore of the conduit is in fluid communication with the fuel pipe and the combustion area of the boiler. A pre-ignition source is positioned in the conduit. The pre-ignition source operates to pre-ignite at least a portion of the fuel flowing through the conduit.

Abstract: A system and method for reducing emissions from a boiler. A boiler generally has a combustion area. The system further includes a fuel pipe for delivering fuel. The system further includes a conduit. A bore extends through the conduit. The bore of the conduit is in fluid communication with the fuel pipe and the combustion area of the boiler. A pre-ignition source is positioned in the conduit. The pre-ignition source operates to pre-ignite at least a portion of the fuel flowing through the conduit.

Abstract: A system and method for reducing emissions from a boiler. A boiler generally has a combustion area. The system further includes a fuel pipe for delivering fuel. The system further includes a conduit. A bore extends through the conduit. The bore of the conduit is in fluid communication with the fuel pipe and the combustion area of the boiler. A pre-ignition source is positioned in the conduit. The pre-ignition source operates to pre-ignite at least a portion of the fuel flowing through the conduit.

Abstract: Ammonia and optionally carbon monoxide are injected into the flue gas containing metals such as mercury in a manner so that there are sufficient amounts of these materials in the flue gas when the flue gas is at a temperature of from 900° F. to 1,450° F. to oxidize the metals within the flue gas. The oxidized metals are then attracted to particulates present in the flue gas. Oxidation is facilitated by a reaction zone stabilizer through which the flue gas flows. The stabilizer provides a stable continuous ignition front. These particulates bound with oxidized metals are removed from the flue gas by a particulate removal device such as an electrostatic precipitator or baghouse. After the ammonia is injected, the flue gas can be rapidly cooled to a temperature below 500° F. to minimize decomposition of oxidized metals in the flue gas.

Abstract: In a method for removing NOx from the flue gas using a coal water slurry, other carbon containing fuel and water, or unburned carbon existing in the furnace itself due to continuing combustion, the ratio of carbon to water is adjusted so that a portion of the carbon forms activated carbon after injection of the fuel slurry into the flue gas. The activated carbon is then available to collect mercury chloride from the flue gas which has been formed through the enhancement of the mercury and chlorine oxidation reaction, enhanced through the heterogeneous reaction mechanism of this same activated carbon in the primary combustion fuel.

Abstract: In a method of removing metals such as mercury from flue gas produced by combustion devices, water or water including a calcium-containing component or water including Cl? anion formers or water including both a calcium-containing component and Cl? anion formers is injected into the flue gas in a manner so that there are sufficient amounts of these materials in the flue gas when the flue gas is at a temperature from about 250° F. to about 350° F. to retain the mercury within the aqueous phase. After the water evaporates, the oxidized mercury is retained on the dry flyash particles present in the flue gas. These flyash particles bound with the oxidized mercury are removed from the flue gas by a particulate removal device, such as an electrostatic precipitator, baghouse filter or cyclone.

Abstract: In a method for removing NOx from the flue gas using a coal water slurry, other carbon containing fuel and water, or unburned carbon existing in the furnace itself due to continuing combustion, the ratio of carbon to water is adjusted so that a portion of the carbon forms activated carbon after injection of the fuel slurry into the flue gas. The activated carbon is then available to collect mercury chloride from the flue gas which has been formed through the enhancement of the mercury and chlorine oxidation reaction, enhanced through the heterogeneous reaction mechanism of this same activated carbon in the primary combustion fuel.

Abstract: In a method for removing mercury from flue gas produced by combustion devices burning coal and other fuels that contain mercury and chlorine the combustion process is controlled to generate a flue gas comprising fly ash containing at least 0.25% unburned carbon, and preferably at least 5.0% unburned carbon. In addition the flue gas is rapidly cooled from a temperature within the range of 1450° F. to 900° F. to a temperature below 900° F. at a rate of at least 1000° F. per second. This step will enhance the concentrations of Cl-atoms and Cl2, which accelerates the rates of mercury oxidation in both the gas phase and on particle surfaces. Finally, the flue gas is directed to the particle removal device for removal of the fly ash to which some of the mercury is bound, and also directed to a wet scrubber for retention of the oxidized mercury vapor in wastewater and solid effluents.

Abstract: In a method of removing metals such as mercury from flue gas produced by combustion devices, water or water including a calcium-containing component or water including Cl? anion formers or water including both a calcium-containing component and Cl? anion formers is injected into the flue gas in a manner so that there are sufficient amounts of these materials in the flue gas when the flue gas is at a temperature from about 250° F. to about 350° F. to retain the mercury within the aqueous phase. After the water evaporates, the oxidized mercury is retained on the dry flyash particles present in the flue gas. These flyash particles bound with the oxidized mercury are removed from the flue gas by a particulate removal device, such as an electrostatic precipitator, baghouse filter or cyclone.

Abstract: Ammonia and optionally carbon monoxide are injected into the flue gas containing metals such as mercury in a manner so that there are sufficient amounts of these materials in the flue gas when the flue gas is at a temperature of from 900° F. to 1,450° F. to oxidize the metals within the flue gas. The oxidized metals are then attracted to particulates present in the flue gas. Oxidation is facilitated by a reaction zone stabilizer through which the flue gas flows. The stabilizer provides a stable continuous ignition front. These particulates bound with oxidized metals are removed from the flue gas by a particulate removal device such as an electrostatic precipitator or baghouse. After the ammonia is injected, the flue gas can be rapidly cooled to a temperature below 500° F. to minimize decomposition of oxidized metals in the flue gas.

Abstract: In a method of measuring heat flux and corrosion in a furnace, pairs of thermocouples are attached to the back side of the furnace wall. One thermocouple of each pair is attached to a tube and the second thermocouple is attached to a web connected to that tube. A temperature differential is determined for each pair at selected time intervals. A decrease in the difference between temperature differentials indicates slag on the furnace wall has melted indicating corrosion can be occurring.

Abstract: In a method of measuring heat flux and corrosion in a furnace, pairs of thermocouples are attached to the back side of the furnace wall. One thermocouple of each pair is attached to a tube and the second thermocouple is attached to a web connected to that tube. A temperature differential is determined for each pair at selected time intervals. A decrease in the difference between temperature differentials indicates slag on the furnace wall has melted indicating corrosion can be occurring.

Abstract: A method for monitoring and reducing corrosion in superheater and reheater furnace tubes measures electrochemical activity associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. A sensor containing two electrodes spaced apart by an insulator is used. The surface of a boiler tube is one of the electrodes. The sensor is connected to a corrosion monitor. The monitor contains a computer and software, which determines a corrosion rate from the measured electrochemical activity. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the furnace operator of the furnace or an Adaptive Process Controller (APC) adjusts one or more burners to change the combustion products that are responsible for the corrosion.

Abstract: A process for stabilizing sludge containing flyash and calcium sulfate formed by a lime or limestone scrubber increases the sludge particles to a size at which leaching of toxic metals from the particles no longer occurs at toxic levels. The sludge is dewatered and injected into the furnace in a manner to cause the flyash to soften and stick together. The agglomerated particles then fall into a bottom ash pit for removal as a common waste.

Abstract: In a process to limit the production of flyash by dry bottom boilers, flyash is collected from flue gas using a collector such as an electrostatic precipitator. The collected flyash is carried in a carrier gas stream to which a fuel is added. The stream is introduced into the boiler in a manner to cause the flyash to soften, agglomerate and fall into the bottom ash pit.

Abstract: A method of recycling fly ash as slag in a wet bottom furnace is described. The furnace may have a cyclone furnace, a pulverized coal furnace, or any other type of furnace producing wet slag. All or part of the collected fly ash is collected and returned to the furnace and combined with enough fuel to melt the ash. Melted ash directed against a wall, floor or side of the cyclone or furnace will flow to the bottom of the furnace so as to facilitate the liquid slag. The fly ash may be collected by an electrostatic precipitator, baghouse, cyclone (multiclone) or other device. The fly ash may be returned to the furnace or the cyclone using air, flue gas, steam, fuel, or other gas as a carrier.