Abstract:
The invention relates to an indirect heating system in which a solid fuel circulates in the form of particles. The inventive system comprises a grinding station, a furnace (7), at least one intermediate silo, a separator, at least one cyclone and, optionally, a gas recirculation fan. The invention is characterized in that a dust extractor (10) captures the finest particles which are subsequently introduced into the furnace (7) by means of at least one specific conduit (52) and burnt by at least one specific burner (71). The aforementioned ultra-fine particles are then stored in a specific silo (10), dosed into a feeding device (61), mixed in well defined proportions with hot air and conveyed to the specific burner (71) through the specific conduit (52).
Abstract:
The invention relates to an indirect heating system in which a solid fuel circulates in the form of particles. The inventive system comprises a grinding station, a furnace (7), at least one intermediate silo, a separator, at least one cyclone and, optionally, a gas recirculation fan. The invention is characterised in that a dust extractor (10) captures the finest particles which are subsequently introduced into the furnace (7) by means of at least one specific conduit (52) and burnt by at least one specific burner (71). The aforementioned ultra-fine particles are then stored in a specific silo (10), dosed into a feeding device (61), mixed in well defined proportions with hot air and conveyed to the specific burner (71) through the specific conduit (52).
Abstract:
Bottom ash and flyash having high LOI is reburned in a pulverized coal furnace. The bottom ash is added to the coal supply before the coal is pulverized. Flyash is added to the pulverized coal stream for injection with the pulverized coal or is separately injected into the furnace at or slightly above the level of the coal burners in the furnace. The bottom ash and flyash is added to the coal in direct proportion of 1% to 3.5% of the coal.
Abstract:
A process for energy recovery and transfer including: warming fresh air in a heat recovery and pressure control unit; feeding waste feed and the warm fresh air into a processor; reducing a moisture content of the waste feed by breaking the waste feed into a fuel powder in the warm fresh air in the processor; filtering contaminated air through an initial filter to remove the fuel powder from the contaminated air; pre-heating the contaminated air in the heat recovery and pressure control unit; raising the temperature of the pre-heated contaminated air in a chamber; passing the chamber discharge air through the heat recovery and pressure control unit to pre-heat contaminated air passing on to the chamber and to warm fresh air passing on to the processor; and filtering terminal air through a terminal filter to remove particles from the terminal air.
Abstract:
The present application and the resultant patent provide a combustion system. The combustion system may include a combustion chamber for combusting a flow of fuel and a flow of air to a flow of flue gases, an overfire air system in communication with the combustion chamber, and a flue gas return line in communication with the overfire air system such that a recycled flue gas flow mixes with an overtire air flow before entry into the combustion chamber.
Abstract:
The subject mater herein relates to coal mills and, more particularly, inferential pulverized fuel flow sensing and manipulation within a coal mill. Various embodiments provide systems, methods, and software to manipulate a primary air flow rate and a coal feed rate into a coal mill to produce a target pulverized fuel flow. Some embodiments include sensing a differential pressure between two or more locations within a coal mill to estimate a recirculated load of coal at one or more stages within the coal mill.
Abstract:
Using oxygen-lean gas as the transport medium in which pulverized fuel solids are conveyed to the burner of a combustion system permits combustion at levels of combustion rate and NOx production under circumstances under which those levels would not be attainable if the transport medium were air.
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 primary air system for a combustion plant provides a flow of primary air to at least one coal pulverizer, which emits pulverized coal in a downstream direction to a furnace. The primary air system includes a first primary air line for feeding hot primary air to the coal pulverizer and a second primary air line for admixing of cold primary air into the hot primary air line at a mixing location positioned upstream of the coal pulverizer. A control system shuts off the flow of primary air to the coal pulverizer, when the coal pulverizer is being repaired or serviced while the furnace is in operation. The control system includes a first flow control butterfly valve disposed in the first primary air line at a position upstream of the mixing location and a second flow control butterfly valve disposed in the second primary air line at a position upstream of the mixing location. A shut-off butterfly valve, disposed in the primary air line intermediate the mixing location and the coal pulverizer, includes a tandem wing supported at a cental location and movable between an open position and a closed position. The tandem wing has parallel, first and second wings forming a space therebetween. A pressure relief line provides fluid communication with the space between the first and second wings when the tandem wing is in the closed position. A pressure relief butterfly valve is disposed in the pressure relief line.
Abstract:
The subject invention relates generally to methods and apparatuses for calcining gypsum. The apparatuses and methods place a gypsum particle optimizer in close association with the impact mill so that all the gypsum supplied to the impact mill has to enter the gypsum particle optimizer prior to the gypsum entering the impact mill, and so that heat generated from the impact mill enters into the gypsum particle optimizer from the impact mill. The gypsum particle optimizer utilizes a rotor to disperse the gypsum throughout the gypsum particle optimizer so that the gypsum is exposed to the heat from the impact mill prior to entering the impact mill. The exposure to the heat removes free water from the gypsum prior to the gypsum entering the impact mill.