1830results about "Lump/pulverulent fuel preparation" patented technology

A method for torrefaction of wood which includes providing a first endless conveyor belt; heating the first endless belt; and positioning a planar wood product on the first belt to heat the wood product by conduction to achieve torrefaction. Other forms provide a second endless belt that disposed in sandwich relation to wood to be torrefied. Some embodiments of the method provide a metal chamber having opposed planar sides dimensioned and configured for receiving a wood sheet with the respective opposed sides of the wood sheet in intimate thermal contact with respective opposed sides of the metal chamber. Other embodiments include the apparatus for torrefaction of an associated wood sheet.

Processes and compositions are provided for decreasing emissions of mercury upon combustion of fuels such as coal. Various sorbent compositions are provided that contain components that reduce the level of mercury and/or sulfur emitted into the atmosphere upon burning of coal. In various embodiments, the sorbent compositions are added directly to the fuel before combustion; are added partially to the fuel before combustion and partially into the flue gas post combustion zone; or are added completely into the flue gas post combustion zone. In preferred embodiments, the sorbent compositions comprise a source of halogen and preferably a source of calcium. Among the halogens, iodine and bromine are preferred. In various embodiments, inorganic bromides make up a part of the sorbent compositions.

Methods involve adding sorbent components, such as calcium oxide, alumina, and silica, as well as optional halogens as part of environmental control. Use of the sorbents leads to significant reductions in sulfur and mercury emissions that otherwise would result from burning coal. Use of the sorbents leads to production of waste coal ash that, while higher in mercury, is nevertheless usable as a commercial product because the mercury in the ash is non-leaching and because the coal ash has a higher cementitious nature by virtue of the increased content of the sorbent components in the ash. Thus, the methods involve adding powders having qualities that lead to the production of a cementitious coal ash while at the same time reducing emissions from a coal burning facility.

Apparatus for biomass torrefaction which includes a serpentine elongated housing, the housing having three generally U-shaped axial portions having first and second axial extremities and an intermediate section, the first and second axial extremities are disposed in normal use at a higher elevation than the first and second axial extremities, the intermediate section being configured for holding a liquid. Other forms of the invention include the method for biomass torrefaction which includes providing a quantity of biomass, providing a liquid heat transfer fluid, providing at least a first housing for holding the heat transfer liquid, elevating the temperature of the liquid heat transfer liquid, heat treating the biomass by passing it through the heat transfer liquid in the first housing at a temperature and duration sufficient to accomplish torrefaction of the wood. In some forms of the method, the process further includes the step of pelletizing the biomass prior to performing the treating step.

PCT No. PCT/JP97/00668 Sec. 371 Date Sep. 25, 1998 Sec. 102(e) Date Sep. 25, 1998 PCT Filed Mar. 5, 1997 PCT Pub. No. WO97/36009 PCT Pub. Date Oct. 2, 1997The use of pulverized coal as the fuel to be injected into metallurgical or combustion furnace becomes possible enabled by improving the transportability thereof. Further, a pulverized coal is provided, which is inhibiting from bridging or channeling in a hopper, or piping choking. A water-soluble inorganic salt having a polar group is made to adhere to pulverized coal which is prepared from raw coal having an average HGI of 30 or above and which is in a dry state at the injection port of a metallurgical or combustion furnace, The inorganic salt is selected from among BaCl2, CaCl2, Ca(NO2)2, Ca(NO3)2, Ca(ClO)2, K2CO3, KCl, MgCl2, MgSO4, NH4BF4, NH4Cl, (NH4)2SO4, Na2CO3, NaCl, NaClO3, NaNO2, NaNO3, NaOH, Na2S2O3, Na2S2O5, HNO3, H2SO4, H2CO3, and HCl.

In embodiments of the present invention, a method of heat treating a solid fuel briquette may include heating the solid fuel briquette using energy from at least one of a heat furnace or an electromagnetic energy system of a solid fuel treatment facility as the solid fuel briquette is moved through the treatment facility to a specified internal temperature, and sealing the heat-treated solid fuel briquette in a vessel for a duration of time.

The present invention harvests and utilizes fluidized bed drying technology and waste heat streams augmented by other available heat sources to dry feedstock or fuel. This method is useful in many industries, including coal-fired power plants. Coal is dried using the present invention before it goes to coal pulverizers and on to the furnace/boiler arrangement. Coal can be intercepted on current coal feed systems ahead of the pulverizers. Drying fuel, such as coal, is done to improve boiler efficiency and reduce emissions. A two-stage bed utilized in the process first “pre-dries and separates” the feed stream into desirable and undesirable feedstock. Then, it incrementally dries and segregates fluidizable and non-fluidizable material from the product stream. This is all completed in a low-temperature, open-air system. Elevation of fan room air temperature is also accomplished using waste heat, thereby making available to the plant system higher temperature media to enhance the feedstock drying process.

The invention relates to a low-temperature furnace smoke sucking exhaust gas and hot air drying composite powder feeding bituminous coal and meagre coal universal type powder preparing system. A middle bin storage type steel ball coal mill hot air power feeding and meagre coal power preparation system is adopted as a prototype, and part of low-temperature furnace smoke is sucked from an outlet of a suction fan by a furnace smoke fan as an inert medium and part of drying mediums to be mixed with hot air taken from an outlet of an air preheater to enter a coal mill for drying and delivering coal powder; the oxygen content of the powder preparation system is reduced, and the explosion preventing requirement on grinding bituminous coal can be met. In addition, part of exhaust gas at an outlet of a power exhauster is led to an inlet of a heat primary fan by an exhaust gas transfer pipeline to be mixed with hot air to enter a primary bellows for delivering the coal powder; the temperature of a primary air and powder mixture and the oxygen concentration of the system are effectively reduced, and the combustion and explosion preventing requirement of bituminous coal delivery is met. Isolating doors are both installed on a furnace smoke system and an exhaust gas transfer system; by the switch control of the isolating doors, the switching of a typical hot air power feeding meagre coal system and a low-temperature furnace smoke exhaust gas and hot air drying composite powder feeding bituminous coal system is realized, and the invention is not only suitable for the meagre coal, but also suitable for the bituminous coal.

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.

The invention relates to a thermal power generation system based on a high-moisture lignite pre-drying upgrading and recovering technology. The thermal power generation system comprises a boiler, a turbine, a condenser, a condensation pump, a low pressure heater, a deaerator, a water feed pump, a high pressure heater, a wet coal bin, a wet coal feeder and a coal mill and is characterized in that a lignite pre-drying device, a drain pump, a dry coal feeder, a dust remover and a heat energy and waste water recovering device are additionally arranged in the power generation system. The invention improves the energy density of fire coal and accordingly increases the efficiency of the boiler, and is capable of reducing the investment of the boiler and a milling system by a larger extent, simultaneously reducing the plant power utilization ratio, further improving the energy source comprehensive utilization efficiency of a thermal power generation plant, recovering a great deal water by using coal to produce water and saving precious water resources. The invention achieves the effects of high efficiency, energy saving, water saving and emission reduction and accords with the industrial policy of developing the low-carbon economy in China.

A method for manufacturing a solid fuel includes the steps of partially or completely separating finely powdered coal from pulverized low-rank coal; mixing the separated low-rank coal with a mixed oil containing a heavy oil and a solvent oil to produce an untreated slurry; heating the untreated slurry to dehydrate the low-rank coal and filling the pores of the low-rank coal with the mixed oil; and separating the solid fuel from the heated slurry by solid-liquid separation. The manufacturing method further includes the step of adding the finely powdered coal separated from the low-rank coal to the solid fuel produced by the solid-liquid separation of the heated slurry. The finely powdered coal separated from the low-rank coal has an average particle size of 0.5 mm or less. An apparatus for the manufacturing method is also disclosed.

An organically complexed nanocatalyst composition is applied to or mixed with coal prior to or upon introducing the coal into a coal burner in order to catalyze the removal of coal nitrogen from the coal and its conversion into nitrogen gas prior to combustion of the coal. This leads to reduced NOx production during coal combustion. The nanocatalyst compositions include a nanoparticle catalyst that is made using a dispersing agent. The dispersing agent includes at least one functional group such as a hydroxyl, a carboxyl, a carbonyl, an amine, an amide, a nitrile, a nitrogen having a free lone pair of electrons, an amino acid, a thiol, a sulfonic acid, a sulfonyl halide, and an. acyl halide. The dispersing agent forms stable, dispersed, nano-sized catalyst particles. The catalyst composition can be formed as a stable suspension to facilitate storage, transportation and application of the catalyst nanoparticles to a coal material. The catalyst composition can be applied before or after pulverizing the coal material or it may be injected directly into the coal burner together with pulverized coal.

A process is provided using non-food or limited-feed agricultural residue and energy crops for energy production, such as ethanol or electricity generation. The agricultural plant material is harvested and baled. The bales are transported to the processing site for storage or immediate processing. The bale strings are first removed, and then the broken bales are shredded. The shredded plant material is then ground to a small size. The ground material is then pelletized to produce densified pellets of the agricultural plant material. The pellets are cooled and then stored or transported to an end user.

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.

The present invention constitutes a heat treatment apparatus like a fluidized-bed dryer for heat treating a particulate material in a low temperature, open-air process. Preferably, available waste heat sources within the surrounding industrial plan operation are used to provide heat to the dryer. Moreover, conveyor means contained within the dryer can remove larger, denser particles that could otherwise impede the continuous flow of the particulate material through the dryer or plug the fluidizing dryer. This invention is especially useful for drying coal for an electricity generation plant.

The invention discloses a cold start oil auxiliary heating system of a boiler and a heat source-less independent starting method of a generating set. The method includes the following steps that: mounting a set of small oil gun igniting system at an inlet air passage of a coal mill for preheating the cold air entering the coal mill and enabling the coal mill to satisfy the working conditions; communicating coal economizer ash conveying gas source of the boiler with a soot blowing steam pipeline of an air preheater through a shutoff valve for supplying soot blowing medium of the air preheater; starting a shaft seal steam valve on a main steam pipeline after the boiler is ignited for supplying steam for shaft seal of a turbine; and supplying steam to an auxiliary steam header of the generating set after the boiler is ignited and the combustion steam reaches a certain parameter, and then supplying steam by the auxiliary steam header for the rolling of a water thermal power deoxidizing and steam-driven feedwater pump. The invention has the advantages that as the cold start of the generating set can be realized through the ignition of the plasma installed in the combustor and the stable combustion technology under the conditions that no starting boiler room is independently established or the external heat source is insufficient, and the operating cost and the labor cost of the power plant are greatly reduced.

The present invention provides combustion products of hydrocarbon fuels and controlled amounts of metal oxide strength enhancing materials. The combustion products are useful as additives to cementitious materials. A hydrocarbon fuel such as coal is introduced into a combustion chamber and selected amounts of materials comprising CaO, SiO₂ and Al₂O₃ are also introduced into and/or downstream from the chamber. The hydrocarbon fuel undergoes combustion while the metal oxide strength enhancing materials react with each other and/or the ash or other reaction products of the hydrocarbon fuel. The combustion products have been found to significantly increase compressive strengths of cements such as Portland cement. A reduction in SO₂ emission levels also results from the introduction of the metal oxide strength enhancing materials into the combustion process.