Abstract:
According to a method for drying fuels in the form of dust, particularly to be fed to a gasification process, such as coal, petroleum coke, biological waste, or the like, wherein the fuel (1) is crushed in a mill (2) and fed to a filter/separator (3) by means of a propellant and drying gas, and at least part of the propellant/drying gas in the circuit is returned to the mill (2) after heating, the known disadvantages are not only to be avoided, but particularly a cost-effective milling and drying method and a corresponding system are to be provided, having low emissions and a low inert gas requirement. This is achieved according to the method in that part of the propellant/drying gas flow is cooled down and dehumidified in a spray tower (6), or the like, wherein part of the dried gas exiting the spray tower is fed to the environment and/or a firing process, and the other part is returned to the propellant/drying gas flow.
Abstract:
A fossil-fuel-fired system, which includes an emissions-control-agent dispenser, a furnace, an emissions monitor and, optionally, a controller, is disclosed. The emissions-control-agent dispenser provides a prescribed amount of organic-emissions-control agent, such as, for example, an opacity-control agent to the fossil-fuel-fired system. The furnace includes an exhaust communicating with the atmosphere. The emissions monitor is capable of measuring at least one property of the flue-gas communicated through the exhaust to the atmosphere. For example, when an organic-emissions-control agent is an opacity-control agent, the emissions monitor has the capability of at least measuring opacity. When included, the controller communicates with at least the emissions-control-agent dispenser and the emissions monitor.
Abstract:
In embodiments of the present invention improved capabilities are described for a system and method for briquetting solid fuel before or after treatment with electromagnetic energy. In the system and method, solid fuel is transported through a continuous feed solid fuel treatment facility, treated using electromagnetic energy, and briquetted after treatment.
Abstract:
A process for mitigation of fouling deposits within a combustion zone, capturing of toxic metal emissions, and reduction of visible sulfur emissions attributable to sulfuric acid mist during coal combustion. SO3 formed during coal combustion is reduced by the addition to the coal of raw, unprocessed magnesium-containing minerals such as magnesite ore or brucite ore. The minerals are pulverized to a fine particle size and combined with pulverized coal to provide a mixture of the particles. The mixture is combusted and the ore particles calcine and decrepitate to very fine magnesium oxide particles that have a significant particle surface area. The magnesium oxide particles react with the SO3 produced during combustion of the coal and also capture toxic metals to reduce the quantity of undesirable stack discharge components.
Abstract:
A fossil-fuel-fired system, which includes an emissions-control-agent dispenser, a furnace, an emissions monitor and, optionally, a controller, is disclosed. The emissions-control-agent dispenser provides a prescribed amount of organic-emissions-control agent, such as, for example, an opacity-control agent to the fossil-fuel-fired system. The furnace includes an exhaust communicating with the atmosphere. The emissions monitor is capable of measuring at least one property of the flue-gas communicated through the exhaust to the atmosphere. For example, when an organic-emissions-control agent is an opacity-control agent, the emissions monitor has the capability of at least measuring opacity. When included, the controller communicates with at least the emissions-control-agent dispenser and the emissions monitor.
Abstract:
An apparatus for separating coarse particles from a stream of gas entrained with a mixture of coarse and fine particles includes an outer casing, an inner casing disposed within the outer casing and configured to define a passageway between the outer casing and the inner casing through which the stream of gas and mixture of coarse and fine particles can flow substantially upwardly, a plurality of angled vanes for imparting a rotational flow to the stream of gas and particles as the stream passes from the passageway to within the inner casing in order to separate the coarse particles from the fine particles entrained within the stream of gas, a plurality of outlets for discharging the stream of gas and fine particles from the apparatus, and at least one distribution vane pivotably mounted with respect to the outlets for controlling the distribution of fine particles among the various outlets by affecting the rotational flow of the stream of gas and fine particles.
Abstract:
The present invention provides a method of operating a solid fuel fired boiler comprising introducing a solid fuel and an iron-bearing material into the boiler. The solid fuel is at least partially combusted in the boiler to produce an ash slag, wherein the ash fusion temperature characteristics (i.e., one or more of the IDT, ST, HT, and FT) of the ash slag are different than the ash fusion temperature characteristics of the ash slag that would result on combustion of the solid fuel alone. The method of the present invention is particularly applicable to slag tap boilers, including cyclone-type boilers. These boilers are, typically, designed to operate with a liquid ash slag. The iron-bearing material may be, but is not limited to, at least one of iron ore beneficiation tailings, iron ore fines, pelletized blends of coal and iron-bearing material, pelletized solid fuel containing iron-bearing compounds, iron-bearing boiler ash, mill scale from steel production, dust from blast furnace gas cleaning equipment, flue dust from sinter plants, and other materials including iron or including material that bears iron. According to the present invention also describes methods of introducing the iron-bearing material into the slag tap combustion apparatus. The method of the invention allows lower sulfur coals, as well as other fuels typically unsuited for use in slag top boilers, to be used in such boilers, significantly reducing SO2 emissions.
Abstract:
A method to reduce waterwall corrosion in a low NO.sub.x boiler includes the steps of locating a waterwall area of a low NO.sub.x boiler where oxidizing conditions exist and deposition of FeS is likely. The combustion air input at the waterwall area is biased to reduce FeS deposition on the waterwall. The biased combustion air input increases the oxidation rate of FeS.sub.2 so as to reduce FeS deposition on the waterwall. The biased combustion air input may be achieved by increasing the air-to-fuel ratio of one burner while reducing the air-to-fuel ratio of another burner, such that the overall air-to-fuel ratio in the low NO.sub.x boiler is substantially constant.
Abstract:
Die Erfindung betrifft eine Einrichtung und ein Verfahren zur Steuerung des Brennstoff-Luft-Verhältnisses bei der Verbrennung gemahlener Kohle in einer Kohlekraftwerksfeuerungsanlage, die Mittel zur pneumatischen Förderung der gemahlenen Kohle zu den Brennern der Kohlekraftwerksfeuerungsanlage sowie Mittel zur Zuführung von Verbrennungsluft zu den Brennern bzw. in den Feuerungsraum der Kohlekraftwerksfeuerungsanlage aufweist und bei der eine Steuerung der Verbrennungsluftmenge und der Tragluftmenge erfolgt. Ziel der Erfindung ist eine hohe Zuverlässigkeit der Steuerung bei geringem Wartungsaufwand der Luftmengenmesseinrichtungen zur Messung der Verbrennungsluft- und der Tragluftmengen. Erfindungsgemäß wird dieses Ziel mit einer Messeinrichtung zur Verbrennungsluftmengenmessung erreicht, die triboelektrische Effekte an in Strömungsrichtung der Verbrennungsluft hintereinander im Verbrennungsluftstrom angeordneten Sensoren nach der Korrelationsmessmethode auswertet und so die Strömungsgeschwindigkeit der Verbrennungsluft misst. Dazu werden in die angesaugte Frischluft zwischen 0,1 mg bis 10 mg feinkörnige Partikel je m 3 Luft mit einem Partikeldurchmesser zwischen 20 μm bis 200 μm eingetragen. Der Partikeleintrag in die angesaugte Frischluft erfolgt insbesondere nur während der Anfahrphase einer Kohlekraftwerksfeuerungsanlage. Bevorzugt erfolgt auch die Tragluftmengenmessung mittels einer triboelektrische Effekte an in Strömungsrichtung der Tragluft hintereinander im Tragluftstrom angeordneten Sensoren auswertenden Korrelationsmesseinrichtung.
Abstract:
This invention is directed to a novel method and system to separate magnetically non-susceptible impurities from coal intended for combustion, and it includes the removal of such impurities together with magnetically susceptible impurities that are collocated within the same lump of coal, prior to the combustion of the coal, by the use of the magnetic properties of the magnetically susceptible impurities. The invention is based on the fact that the former impurities are normally collocated in the same lumps of coal as the latter, especially as far as pyrite and cinnabar are concerned, provided the lumps have not been liberated, in particular, they meet the requirement that at least 50% by mass of the coal lumps should be at least 2 mm in maximum dimension.