18937 results about "Flue gas" patented technology

In a method for generating energy in an energy generating installation (10) having a gas turbine (12), in a first step, an oxygen-containing gas is compressed in a compressor (13, 14) of the gas turbine (12), in a second step the compressed gas is supplied, with the addition of fuel, for combustion in a combustion chamber (15), in a third step the hot flue gas from the combustion chamber (15) is expanded in a turbine (16) of the gas turbine (12) so as to perform work, and, in a fourth step, a branched-off part stream of the expanded flue gas is recirculated into a part of the gas turbine (12) lying upstream of the combustion chamber (15) and is compressed. A reduction in the CO₂ emission, along with minimal losses of efficiency, is achieved in that carbon dioxide (CO₂) is separated from the circulating gas in a CO₂ separator (19), and in that measures are taken to compensate for the efficiency losses in the gas turbine cyclic process which are associated with the CO₂ separation.

Certain embodiments and aspects of the present invention relate to photobioreactor apparatus (100) designed to contain a liquid medium (108) comprising at least one species of photosynthetic organism therein, and to methods of using the photobioreactor apparatus (100) as part of a gas-treatment process and system able to at least partially remove certain undesirable pollutants from a gas stream (608). In certain embodiments, the disclosed photobioreactor apparatus (100 can be utilized as part of an integrated combustion method and system, wherein photosynthetic organisms utilized within the photobioreactor (100) at least partially remove certain pollutant compounds contained within combustion gases, e.g. CO₂ and/or NO_X, and are subsequently harvested from the photobioreactor (100), processed, and utilized as a fuel source for a combustion device (e.g. an electric power plant generator and/or incinerator).

A method of generating energy in a power plant (30) having a gas turbine (29), includes a first step a gas containing air (1) is compressed in a first compressor (2) of the gas turbine (29), a second step the compressed gas (3, 3a, 3b; 5; 7a, 7b) is fed to a combustion process with the addition of fuel (8) in a combustor (23), a third step the hot flue gas (9) from the combustor (23) is expanded in an expander or a turbine (10), driving a generator (18), of the gas turbine (29) while performing work, and a fourth step a partial flow of the expanded flue gas (11) is recirculated to the inlet of the first compressor (2) and admixed with the gas containing air (1). Carbon dioxide (CO₂) is separated from the compressed gas (3, 3a, 3b; 5; 7a, 7b) in a CO₂ separator (6) before the third step. In such a method, the overall size and energy costs are reduced by virtue of the fact that, to permit increased CO₂ concentrations in the CO₂ separator (6), not more than about 70% of the carbon dioxide contained in the compressed gas (3, 3a, 3b; 5, 5a, 5b; 7a, 7b) is removed from the compressed gas (3, 3a, 3b; 5, 5a, 5b; 7a, 7b).

A method and apparatus for synthesizing ethanol using synthetic routes via synthesis gas are disclosed. A method and apparatus for gasifying biomass, such as biomass, in a steam gasifier that employs a fluidized bed and heating using hot flue gases from the combustion of synthesis gas is described. Methods and apparatus for converting synthesis gas into ethanol are also disclosed, using stepwise catalytic reactions to convert the carbon monoxide and hydrogen into ethanol using catalysts including iridium acetate.

An adsorbent composition for removing mercury from a flue gas stream, and a method of its use. The composition is a powdered activated carbon having at least one of a halogen-containing component and an alkaline component dispersed thereon. A flow agent can be composited with the material to maintain flowability in situ.

This invention is related to so-called combined cycle co-generation installations, and it addresses present concerns of the industry. Among these, combustion stability, corrosion (due to large water content in the flue gases), large heat transfer areas, and the like. In some embodiments, an additional heat exchanger is added to heat combustion air with a portion of the exhaust gases resulting from an engine, preferably a gas turbine. As a result, the efficiency of the cycle will improve, the oxidant will be enriched by above 50% oxygen, the combustion process will be enhanced, and the dimensions of the boiler may be reduced. It is considered that the combustion air will require between 10% and 80% of the total flue gas volume, more preferably between 20% and 40%. This is the portion of the flue gases sent through the heat exchanger. A control system designed to optimize the flow of the different streams is also presented. Other inventive embodiments forego heat exchanges in lieu of precise control of two flows of exhaust gas, with preferred addition of additional oxidant to the boiler bumers.

Various methods for decreasing the amount of nitrogen oxides released to the atmosphere as a component of combustion gas mixtures are provided. The methods specifically provide for the removal of nitric oxide and nitrogen dioxide (NOx) from gas mixtures emitted from stationary combustion systems. In particular, methods for improving efficiency of nitrogen oxide reduction from combustion systems include injecting metal-containing compounds into the main combustion zone and/or the reburning zone of a combustion system. The metal containing compounds react with active combustion species, and these reactions change radical concentrations and significantly improve NOx conversion to molecular nitrogen. The metal-containing additives can be injected with the main fuel, in the main combustion zone, with secondary or reburning fuel addition, or at several locations in the main combustion zone and reburning zone. Optionally, nitrogenous reducing agents and/or overfire air can be injected downstream to further increase NOx reduction.

A method and installation are disclosed which can, for example, provide for reliable, low-Nox-emission operation of a gas turbine installation with hydrogen-rich fuel gas. An exemplary gas turbine installation includes an arrangement for flue gas recirculation into a compressor inlet and for fuel gas dilution. Oxygen content in combustion air can be reduced by recirculation of recooled flue gas, and the fuel gas can be diluted with compressed flue gas. The oxygen reduction in the combustion air can lead to minimum residual oxygen in the flue gas which can be used for fuel gas dilution. As a result of the flue gas recirculation, water content in the combustion air can be increased by feedback of the water which results as a combustion product. The oxygen reduction, increased water content, and fuel dilution can reduce the flame velocity of hydrogen-rich fuel gases and enable a robust, reliable and low-emission combustion.

A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

Bromine-containing compounds, added to the coal, or to the boiler combustion furnace, are used to enhance the oxidation of mercury, thereby enhancing the overall removal of mercury in downstream pollution control devices. The method is applicable to utility power plants equipped with wet FGD systems, as well as those plants equipped with spray dryer absorber FGD systems.

A new method for the removal of environmental compounds from gaseous streams, in particular, flue gas streams. The new method involves first oxidizing some or all of the acid anhydrides contained in the gas stream such as sulfur dioxide (SO₂) and nitric oxide (NO) and nitrous oxide (N₂O) to sulfur trioxide (SO₃) and nitrogen dioxide (NO₂). The gas stream is subsequently treated with aqua ammonia or ammonium hydroxide which captures the compounds via chemical absorption through acid-base or neutralization reactions. The products of the reactions can be collected as slurries, dewatered, and dried for use as fertilizers, or once the slurries have been dewatered, used directly as fertilizers. The ammonium hydroxide can be regenerated and recycled for use via thermal decomposition of ammonium bicarbonate, one of the products formed. There are alternative embodiments which entail stoichiometric scrubbing of nitrogen oxides and sulfur oxides with subsequent separate scrubbing of carbon dioxide.

Power plants and process for lowering CO₂ emissions generally includes extracting a portion of the recirculated CO₂-rich flue gas mid-way through the compression pathway of a gas turbine and removing the CO₂ in a separation unit. The remaining portion of the CO₂ rich flue gas (i.e., the portion of the recirculated flue gas that was not fed to the separation unit) is mixed with fresh air coming from an additional compressor-expander and then fed back to the compression pathway. As a result, flue gas recirculation increases the CO₂ concentration within the working fluid, leading to an additional increase in CO₂ partial pressure. As the concentration and partial pressure of CO₂ is increased, a lower energy penalty is observed to remove the CO₂. Moreover, a reduced volume is fed to the CO₂ separation unit during operation. Consequently, the size of the separation equipment can be reduced as well as the energy required for the separation process.

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.

Sorbents for removal of mercury and other pollutants from gas streams, such as a flue gas stream from coal-fired utility plants, and methods for their manufacture and use are disclosed. The methods include mixing sorbent substrate particles with a sulfide salt and a metal salt to form a metal sulfide on the outer surface of the sorbent particles.

Disclosed herein, without limitation, are activated carbon honeycomb catalyst beds and systems for removing mercury and other toxic metals from a process stream, i.e, from flue gas of a coal combustion system. The activated carbon honeycomb can for example remove greater than 90% mercury from flue gas with a simple design and without adding material to the flue gas. Also disclosed herein, and without limitation, are methods for manufacturing and using the disclosed honeycomb catalyst beds and systems.

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.

An integrated power production system including a fossil fuel power plant for processing fossil based fuel such as coal or natural gas arranged in tandem with a carbonate fuel cell having an anode and a cathode section. The flue gas of the power plant serves exclusively as the inlet gas for the cathode section of the fuel cell. Anode exhaust gas leaving the anode section of the fuel cell is subjected to processing including sequestration of the carbon dioxide in the exhaust gas.

The present invention relates to a method to catalyze the oxidation of Hg(0) in a flue gas stream prior to standard emissions control equipment. The oxidized mercury has been found to be more condensable than Hg(0) and consequently more easily removed from the gas phase. Accordingly, mercury in its oxidized form can be trapped from a flue gas stream or the like by absorption onto a solid mass or can be more efficiently removed from flue gas streams by wet processes such as a two-stage wet FGD. The gist underlying the inventive concept of the instant invention relates to the use of a porous bed of gold-coated material that is saturated with Hg(0) to the point that the gold in the presence of HCl in the exhaust stream catalyses the oxidation of Hg(0).

Impure carbon dioxide (“CO₂”) comprising a first contaminant selected from the group consisting of oxygen (“O₂”) and carbon monoxide (“CO”) is purified by separating expanded impure carbon dioxide liquid in a mass transfer separation column system. The impure carbon dioxide may be derived from, for example, flue gas from an oxyfuel combustion process or waste gas from a hydrogen (“H₂”) PSA system.

A process for sequestering carbon dioxide from the flue gas emitted from a combustion chamber is disclosed. In the process, a foam including a foaming agent and the flue gas is formed, and the foam is added to a mixture including a cementitious material (e.g., fly ash) and water to form a foamed mixture. Thereafter, the foamed mixture is allowed to set, preferably to a controlled low-strength material having a compressive strength of 1200 psi or less. The carbon dioxide in the flue gas and waste heat reacts with hydration products in the controlled low-strength material to increase strength. In this process, the carbon dioxide is sequestered. The CLSM can be crushed or pelletized to form a lightweight aggregate with properties similar to the naturally occurring mineral, pumice.

The embodiment of the invention discloses a method and a system for processing oil field wastes. The method for processing the oil field wastes comprises the following steps: conveying initial materials to a heating cavity, and heating the heating cavity by using high-temperature flue gas, so as to obtain mixed steam and solid residues; carrying out condensation and separation on the mixed steam, so as to obtain oil, water and a noncondensable gas, wherein the oil and the noncondensable gas are used for combusting to obtain the high-temperature flue gas, and the solid residues are discharged out of the heating cavity. According to the method, the heating cavity is indirectly heated by using the high-temperature flue gas, so that the initial materials inside the heating cavity are subjected to thermal decomposition, solid residues free of oil, the noncondensable gas and oil are obtained from the mixed steam generated by thermal decomposition after a series of treatments, and then the noncondensable gas and oil are used for combusting to generate the high-temperature flue gas. Compared with the prior art, the method disclosed by the invention has the advantages that decomposition is carried out without adding a cracking agent, and thermal decomposition can be directly carried out on the oil field wastes in different regions, therefore, the method and the system are better in universality.

An environmentally beneficial method of producing methanol from varied sources of carbon dioxide including flue gases of fossil fuel burning power plants, industrial exhaust gases or the atmosphere itself. Converting carbon dioxide by an electrochemical reduction of carbon dioxide in a divided electrochemical cell that includes an anode in one cell compartment and a metal cathode electrode in another cell compartment that also contains an aqueous solution comprising methanol and an electrolyte of one or more alkyl ammonium halides, alkali carbonates or combinations thereof to produce therein a reaction mixture containing carbon monoxide and hydrogen which can be subsequently used to produce methanol while also producing oxygen in the cell at the anode.

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.

The method for removing mercury from a flue gas stream of the present invention is comprised of first treating a sorbent with a metal halide, and then contacting a sufficient amount of the sorbent with a gas stream for a sufficient amount of time to bind with a desired amount of the mercury in said gas stream. The metal is selected from Groups I and II of the periodic table of the elements. The halide is selected from the group consisting of I, Br, Cl. The metal halide comprises from about 0.5% to 25% by weight of said treated sorbent.

Methods and apparatus for reducing the content of nitrogen oxides in the flue gases produced by the combustion of fuel gas and combustion air introduced into a burner connected to a furnace are provided. The methods basically comprise the steps of conducting the combustion air to the burner, providing a chamber outside of the burner and furnace for mixing flue gases from the furnace with the fuel gas, discharging the fuel gas in the form of a fuel jet into the mixing chamber so that flue gases from the furnace are drawn into the chamber and mixed with and dilute the fuel gas therein and conducting the resulting mixture of flue gases and fuel gas to the burner wherein the mixture is combined with the combustion air and burned in the furnace.

A method and a system capable of removing carbon dioxide directly from ambient air, and obtaining relatively pure CO₂. The method comprises the steps of generating usable and process heat from a primary production process;

• • applying the process heat from said primary process to water to co-generate substantially saturated steam, alternately repeatedly exposing a sorbent to removal and to capture and regeneration system phases, wherein said sorbent is alternately exposed to a flow of ambient air during said removal phase, thereby enabling said sorbent to sorb, and therefore remove, carbon dioxide from said ambient air, and to a flow of the co-generated steam during the regeneration and capture phase, after the sorbent has adsorbed the carbon dioxide, thereby enabling regeneration of such sorbent, and the resultant capture in relatively pure form of the adsorbed carbon dioxide. This process can also be carried out in more efficient form by admixing with the air a minor amount of a flue gas or an effluent gas containing a higher concentration of carbon dioxide than exists in the atmosphere, most preferably following a pre-treatment. The carbon dioxide can be stored for further use, or sequestered permanently following the capture: The adsorbent is exposed to air at substantially ambient conditions and the adsorbent is exposed to the co-generated steam at a temperature in the range of not greater than about 130° C. The system provides the sorbent substrate and equipment for carrying out the above method, and provides for obtaining purified carbon dioxide for further use in agriculture and chemical processes, including manufacturing hydrocarbon fuels, or for permanent sequestration, as needed.

Carbon dioxide-containing gas such as flue gas and a carbon dioxide-rich stream are compressed and the combined streams are then treated to desorb moisture onto adsorbent beds and then subjected to subambient-temperature processing to produce a carbon dioxide product stream and a vent stream. The vent stream is treated to produce a carbon dioxide-depleted stream which can be used to desorb moisture from the beds, and a carbon dioxide-rich stream which is combined with the carbon dioxide-containing gas.

An environmentally beneficial method of producing methanol from varied sources of carbon dioxide including flue gases of fossil fuel burning powerplants, industrial exhaust gases or the atmosphere itself. Converting carbon dioxide by electrochemical reduction produces formic acid acid and some formaldehyde and methanol mixtures. The formic acid can be used as source of carbon as well as hydrogen to produce methanol, dimethyl ether and other products.

The invention provides a method for processing de-nitration on the boiler smoke, belonging to the environmental protective technique. The method comprises: ejecting ozone O3 into the low-temperature section of smoke channel of boiler whose temperature ranges from 110-150Deg. C; oxygenizing the nitric oxide NO into high-state nitrogen oxide as NO2, NO3 or N2O5; washing the smoke with alkali liquor to remove the nitrogen oxide in the smoke. Compared to other de-nitration method, said invention has higher efficiency, lower cost, and non-secondary pollution, while the absorption effect combined with alkali liquor can reach more than 80%. In addition, the invention can apply variable boiler devices, which is not relative to the burning condition of boiler.

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.