2091results about "Emission prevention" patented technology

A system and method for removing mercury from the flue gas of a coal-fired power plant is described. Mercury removal is by adsorption onto a thermally activated sorbent produced in-situ at the power plant. To obtain the thermally activated sorbent, a lance (thief) is inserted into a location within the combustion zone of the combustion chamber and extracts a mixture of semi-combusted coal and gas. The semi-combusted coal has adsorptive properties suitable for the removal of elemental and oxidized mercury. The mixture of semi-combusted coal and gas is separated into a stream of gas and semi-combusted coal that has been converted to a stream of thermally activated sorbent. The separated stream of gas is recycled to the combustion chamber. The thermally activated sorbent is injected into the duct work of the power plant at a location downstream from the exit port of the combustion chamber. Mercury within the flue gas contacts and adsorbs onto the thermally activated sorbent. The sorbent-mercury combination is removed from the plant by a particulate collection system.

A carbon dioxide separation system includes a compressor for receiving an exhaust gas comprising CO2 and generate a compressed exhaust gas and a separator configured to receive the compressed exhaust gas and generate a CO2 lean stream. The separator includes a first flow path for receiving the compressed exhaust gas, a second flow path for directing a sweep fluid therethrough, and a material with selective permeability of carbon dioxide for separating the first and the second flow paths and for promoting carbon dioxide transport therebetween. The system further includes an expander coupled to the compressor for receiving and expanding the CO2 lean stream to generate power and an expanded CO2 lean stream.

A system 26 for removing elemental mercury or mercury compounds handles carbonaceous sorbent 28 of a starter batch stored in a silo 30 in an agglomerated state. The sorbent 28 is fed by a feeder 32 to a separation device 34, which comminutes (if necessary) and de-agglomerates the sorbent particles 28 to their primary size distribution. This device 34 may be a particle-particle separator or a jet mill, where compressed air or high-pressure steam is the energy source. The de-agglomerated sorbent 28 of a contact batch created from the starter batch is conveyed by an airsteam for injection at a contact location 66 in a flue gas duct whereat carbonaceous sorbent of the contact batch adsorbs mercury from the flue gas.

Ultra cleaning of combustion gas to near zero concentration of residual contaminants followed by the capture of CO2 is provided. The high removal efficiency of residual contaminants is accomplished by direct contact cooling and scrubbing of the gas with cold water. The temperature of the combustion gas is reduced to 0-20 degrees Celsius to achieve maximum condensation and gas cleaning effect. The CO2 is captured from the cooled and clean flue gas in a CO2 absorber (134) utilizing an ammoniated solution or slurry in the NH3—CO2H2O system. The absorber operates at 0-20 degrees Celsius. Regeneration is accomplished by elevating the pressure and temperature of the CO2-rich solution from the absorber. The CO2 vapor pressure is high and a pressurized CO2 stream, with low concentration of NH3 and water vapor is generated. The high pressure CO2 stream is cooled and washed to recover the ammonia and moisture from the gas.

There is provided a process for the capture and sequestration of carbon dioxide that would otherwise enter the atmosphere and contribute to global warming and other problems. CO2 capture is accomplished by reacting carbon dioxide in flue gas with an alkali metal carbonate, or a metal oxide, particularly containing an alkaline earth metal or iron, to form a carbonate salt. A preferred carbonate for CO2 capture is a dilute aqueous solution of additive-free (Na2CO3). Other carbonates include (K2CO3) or other metal ion that can produce both a carbonate and a bicarbonate salt. Examples of suitable metal oxides include several alkaline earths including CaO and MgO. The captured CO2 is preferably sequestered using any available mineral or industrial waste that contains calcium magnesium or iron in non-carbonate forms, or iron in the Fe+2 oxidation state.

Carbon dioxide is separated from a feed gas, preferably derived from flue gas from an oxyfuel combustion process, in a membrane separation system to produce separated carbon dioxide gas which is fed to the oxyfuel combustion process to improve the performance of the process.

A system 26 for removing elemental mercury or mercury compounds handles carbonaceous sorbent 28 of a starter batch stored in a silo 30 in an agglomerated state. The sorbent 28 is fed by a feeder 32 to a separation device 34, which comminutes (if necessary) and de-agglomerates the sorbent particles 28 to their primary size distribution. This device 34 may be a particle-particle separator or a jet mill, where compressed air or high-pressure steam is the energy source. The de-agglomerated sorbent 28 of a contact batch created from the starter batch is conveyed by an airsteam for injection at a contact location 66 in a flue gas duct whereat carbonaceous sorbent of the contact batch adsorbs mercury from the flue gas.

A method of generating electrical power in which a synthesis gas stream generated in a gasifier is combusted in an oxygen transport membrane system of a boiler. The combustion generates heat to raise steam to in turn generate electricity by a generator coupled to a steam turbine. The resultant flue gas can be purified to produce a carbon dioxide product.

A flue gas control system of a coal combustion boiler comprises an HCl atomizer that sprays hydrogen chloride to flue gas from a coal combustion boiler that uses coal as a fuel; NOx removing apparatus that removes nitrogen oxides by ammonia denitration by adding ammonia to the flue gas after spraying hydrogen chloride and oxidizes mercury; an air preheater that recovers heat in the gas after removal of nitrogen oxides; a precipitator that removes particulates in the gas; an activated carbon atomizer that sprays activated carbon into the gas after particulate collection; a bag filter that collects activated carbon having adsorbed mercury; a desulfurizer that removes sulfur oxides in the flue gas after removal of activated carbon; a stack that discharges the gas which has undergone desulfurization to outside; and an ORP meter that measures an oxidation reduction potential for feeding air to a slurry absorbent in the desulfurizer.

An apparatus and method for absorbing and recovering carbon dioxide from flue gas using ammonia water as an absorbent, including an absorption column and a circulation cooler connected to the absorption column so that a high-temperature absorbent is recovered from the absorption column, cooled to a preset temperature, and then supplied again into the absorption column, in order to dissipate absorptive heat generated when carbon dioxide is absorbed from the flue gas.

A gas cleaning system, which is operative for cleaning a process gas containing carbon dioxide and sulphur dioxide, comprises a combined cooling and cleaning system (16), and a CO2-absorber. The combined cooling and cleaning system (16) comprises a first gas-liquid contacting device (50) located upstream of the CO2-absorber and operative for cooling the process gas by means of a cooling liquid, and for absorbing into the cooling liquid sulphur dioxide of the process gas, such that a cooling liquid containing sulphate is obtained. The combined cooling and cleaning system (16) further comprises a second gas-liquid contacting device (94) located downstream of the CO2-absorber and operative for removing ammonia from the process gas, which has been treated in the CO2-absorber, by means of bringing the process gas containing ammonia into contact with the cooling liquid containing sulphate.

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.

A system and process to provide integrated control for the pyrolytic composition of organic (biomass) waste products especially for municipal solid waste systems. The system includes integrated control that monitors biomass waste stream throughout the entire system and the products produced therefrom and includes presorting, controlling the amount of material processed in a continuous manner, shredding, removing moisture in a continuous process that is controlled and providing the waste stream to the distillation unit for pyrolytic action where it is converted into gaseous fuel and a char residue. The gaseous fuel is scrubbed clean and monitored and stored and reused to provide heat to the system. The entire system may be self-sustaining and continuous with very little or no human intervention. An integrated real time computer control system includes sensors and measuring devices with all the major components to ensure integrated efficiency.

A method of scrubbing mercury compounds and nitrogen oxides from a gas stream employing a scrubbing operation. The method involves the contact of the stream which contains mercury, SOx and NOx compounds with a sorbent to remove at least a portion of the latter compounds. This results in a partially cleaned stream. The method further involves contacting the latter stream with an oxidant to oxidize and remove substantially all residual nitrogen oxides, mercury and mercury compounds remaining in the stream.

A method for separation of CO2 from the combustion gas from a thermal power plant fired with fossil fuel, wherein the combustion gas from the thermal power plant is used as cooled, compressed and reheated by combustion of natural gas in a combustion chamber to form an exhaust gas, where the exhaust gas is cooled an brought in contact with an absorbent absorbing CO2 from the exhaust gas to form a low CO2 stream and an absorbent with absorbed CO2, and where the low CO2 stream is heated by means of heat exchanges against the hot exhaust gas leaving the combustion chamber before it is expanded in turbines, is described. A plant for performing the method and a combined plant is also described.

A system for sequestering carbon emissions from a fuel combustor generally includes a combustion gas extraction module for extracting combustion gas from a fuel combustor and a greenhouse facility for receiving the extracted combustion gas and having at least one vegetation supporting soil bed for absorbing carbon dioxide from the received combustion gas. The extraction module includes a particulate removal unit for removing pollutants from the extracted combustion gas and a heat exchanger in downstream fluid communication with the particulate removal unit for cooling the extracted combustion gas.

An air pollution control apparatus according to an embodiment of the present invention includes: a stack that discharges flue gas discharged from a boiler outside; a blower that is provided downstream of the stack and draws in the flue gas; and a CO2 recovering apparatus that recovers CO2 in the flue gas drawn in by the blower. The stack includes a controlling unit that suppresses release of the flue gas outside from the stack and suppresses inflow of atmosphere to the stack, and the controlling unit is a channel forming unit that forms a serpentine channel through which the flue gas and the atmosphere in the stack flow.

A combined cycle power plant includes a compressor section including a compressor inlet and a compressor outlet, and a turbine section operatively connected to the compressor section. The turbine section includes a turbine inlet and a turbine outlet. A heat recovery steam generator (HRSG) is fluidly connected to the turbine outlet. A combustor includes a head end and a combustor discharge. The head end is fluidly connected to the compressor outlet and the combustor discharge is fluidly connected to the turbine inlet. A carbon dioxide collection system is fluidly connected to one of the compressor outlet and the head end of the combustor. The carbon dioxide collection system is configured and disposed to extract a first fluid comprising carbon dioxide and a second fluid from a substantially oxygen free fluid flow passed from the one of the compressor outlet and the head end of the combustor.

Chlorine and sulfide species are separately introduced to a flue gas passing through a scrubber in order to remove the elemental and oxidized mercury from the gas through the precipitation of mercuric sulfide at near 100% efficiency.

A method of reducing pollutants exhausted into the atmosphere from the combustion of fossil fuels. The disclosed process removes nitrogen from air for combustion, separates the solid combustion products from the gases and vapors and can capture the entire vapor / gas stream for sequestration leaving near-zero emissions. The invention produces up to three captured material streams. The first stream is contaminant-laden water containing SOx, residual NOx particulates and particulate-bound Hg and other trace contaminants. The second stream can be a low-volume flue gas stream containing N2 and O2 if CO2 purification is needed. The final product stream is a mixture comprising predominantly CO2 with smaller amounts of H2O, Ar, N2, O2, SOX, NOX, Hg, and other trace gases.

A gasifier 10 includes a first chemical process loop 12 having an exothermic oxidizer reactor 14 and an endothermic reducer reactor 16. CaS is oxidized in air in the oxidizer reactor 14 to form hot CaSO4 which is discharged to the reducer reactor 16. Hot CaSO4 and carbonaceous fuel received in the reducer reactor 16 undergo an endothermic reaction utilizing the heat content of the CaSO4, the carbonaceous fuel stripping the oxygen from the CaSO4 to form CaS and a CO rich syngas. The CaS is discharged to the oxidizer reactor 14 and the syngas is discharged to a second chemical process loop 52. The second chemical process loop 52 has a water-gas shift reactor 54 and a calciner 42. The CO of the syngas reacts with gaseous H2O in the shift reactor 54 to produce H2 and CO2. The CO2 is captured by CaO to form hot CaCO3 in an exothermic reaction. The hot CaCO3 is discharged to the calciner 42, the heat content of the CaCO3 being used to strip the CO2 from the CaO in an endothermic reaction in the calciner, with the CaO being discharged from the calciner 42 to the shift reactor 54.

The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

A system for sequestering carbon emissions from a fuel combustor generally includes a combustion gas extraction module for extracting combustion gas from a fuel combustor and a greenhouse facility for receiving the extracted combustion gas and having at least one vegetation supporting soil bed for absorbing carbon dioxide from the received combustion gas. The extraction module includes a particulate removal unit for removing pollutants from the extracted combustion gas and a heat exchanger in downstream fluid communication with the particulate removal unit for cooling the extracted combustion gas.

Sorbent components containing calcium, alumina, silica, and halogen are used in combination during coal combustion to produce environmental benefits. Sorbents are added to the coal ahead of combustion and / or are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components ● reduce emissions of mercury and sulfur; ● reduce emissions of elemental and oxidized mercury; ● increase the efficiency of the coal burning process through de-slagging of boiler tubes; ● increase the level of Hg, As, Pb, and / or Cl in the coal ash; ● decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and ● make a highly cementitious ash product.

A system for removing mercury from combustion gas. The system includes a combustion device, a stack, and a duct system that couples the combustion device to the stack. The system further comprises an injection system that is coupled to the duct system. The injection system injects sorbents including alkali-based sorbents and carbon-based sorbents into the duct system.

A vertical scrubber (1) for exhaust gas from a marine vessel is described. An exhaust gas tube (2) is substantially coaxially arranged through the bottom of a lower scrubbing chamber (3) and is released though an exhaust gas outlet (20) being coaxially arranged through the top of an upper scrubbing chamber (13). A lower scrubbing chamber deflection body (4) is arranged above the opening of the exhaust gas tube (2) for redirecting the exhaust gas towards the walls of the scrubber and create turbulent gas flow, where one or more lower chamber water injector(s) (6, 6′) is (are) arranged above the lower scrubbing chamber deflection body (4), to introduce scrubbing water, and where a lower chamber exhaust gas outlet (12) is arranged at the top of the lower scrubbing chamber (3) as a coaxial constriction, for withdrawing the partly scrubbed exhaust gas from the first scrubbing chamber and introducing the gas into the upper scrubbing chamber (13).

A carbon-dioxide-capture-type steam power generation system 1 according to the present invention comprises a boiler 6 producing an exhaust gas 5 by combusting a fuel 2 and having a flue 8; an absorbing unit 40 being configured to absorb the carbon-dioxide contained in the exhaust gas 5 into an absorbing solution; and a regenerating unit 44 being configured to release the carbon dioxide gas from the absorbing solution absorbing the carbon dioxide and discharge the released carbon dioxide gas. Further, in this system, a reboiler 49 is provided for receiving a heating-medium as heat source, producing a steam 43 and supplying the produced steam 43 to the regenerating unit 44. Additionally, in the flue 8 of the boiler 6, a boiler-side heat exchanger 61 is provided for heating the heating-medium by the exhaust gas 5 passing therethrough.