A contaminated gas stream can be passed through an in-line mixing device, positioned in a duct containing the contaminated gas stream, to form a turbulent contaminated gas stream. One or more of the following is true: (a) a width of the in-line mixing device is no more than about 75% of a width of the duct at the position of the in-line mixing device; (b) a height of the in-line mixing device is no more than about 75% of a height of the duct at the position of the in-line mixing device; and (c) a cross-sectional area of the mixing device normal to a direction of gas flow is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device. An additive can be introduced into the contaminated gas stream to cause the removal of the contaminant by a particulate control device.

A gas combustion treatment device that subjects an ammonia-containing gas, a hydrogen cyanide-containing gas, and a hydrogen sulfide-containing gas to combustion treatment includes: a first combustion unit configured to introduce therein fuel, the ammonia-containing gas, the hydrogen cyanide-containing gas, and air and burn and reduce the fuel and the gases at an air ratio lower than 1; a second combustion unit provided downstream of the first combustion unit and configured to burn and reduce, in a reducing atmosphere, nitrogen oxide in a first combustion gas sent from the first combustion unit; and a third combustion unit provided downstream of the second combustion unit and configured to introduce therein hydrogen sulfide-containing gas with air in addition to a second combustion gas sent from the second combustion unit.

Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects soot/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide, has a carbon content of 0.05 wt % or more, and has a defect site in which oxygen deficiency occurs in a crystal structure.

A method and an arrangement for recovering heat from flue gas of a boiler (10). The method comprises passing the flue gas (G) of the boiler though a flue gas cooling unit (1), cooling the flue gas (G) by transferring heat from the flue gas (G) into a circulation (3) of a flue gas cooling liquid (CL), transferring heat energy of said flue gas cooling liquid (CL) into a heat pump (2), and arranging the heat pump (2) for receiving heat energy also from a circulation arrangement (8) of a district cooling system. The heat pump (2) is coupled to a circulation arrangement (6) of a district heating system, wherein the method further comprises transferring in the heat pump (2) heat energy (H) received from said cooling liquid (CL) and from said circulation arrangement (8) of district cooling system into said circulation arrangement (6) of district heating system, for lowering the temperature of said flue gas cooling liquid (CL) and cooling fluid of said district cooling system, and raising the temperature of heating fluid of said district heating system.

Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects ash dust/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide including vanadium pentoxide and has a defect site in which an oxygen atom is deficient in a crystal structure of the vanadium pentoxide.

An exhaust gas treatment device includes an exhaust gas line where a combustion exhaust gas discharged from a power generation facility flows through, an exhaust gas line where a second combustion exhaust gas discharged from a second power generation facility flows through, exhaust gas exhaust line disposed by branching off from exhaust gas line, discharging a part of combustion exhaust gases as exhaust combustion exhaust gases, a nitrogen oxide removing unit removing nitrogen oxide contained in an integrated combustion exhaust gas that integrates the combustion exhaust gases, an integrated waste heat recovery boiler recovering waste heat from the integrated combustion exhaust gas, and a CO.sub.2 recovery unit recovering CO.sub.2 contained in the integrated combustion exhaust gas by using CO.sub.2 absorbing liquid.

An exhaust gas treatment device includes an exhaust gas line through which a combustion exhaust gas discharged from a power generation facility flows, a waste heat recovery boiler recovering waste heat of the combustion exhaust gas, a branch exhaust gas line provided to be connected between a front stage and a downstream stage of the waste heat recovery boiler on a main exhaust gas line, a nitrogen oxide removal unit removing nitrogen oxide in an integrated combustion exhaust gas into which a combustion exhaust gas flowing through the main exhaust gas line and a combustion exhaust gas flowing through the branch exhaust gas line are integrated, an integrated waste heat recovery boiler recovering waste heat of the integrated combustion exhaust gas from which nitrogen oxide has been removed, and a CO.sub.2 recovery unit recovering CO.sub.2 in the integrated combustion exhaust gas.

Devices, systems, facilities, and methods for post combustion capture of emissions from a natural gas generator used to power a data center disclosed herein. The facility includes a process for capturing and sequestering CO.sub.2 from a post combustion capture of the natural gas generator utilizing the heat from the flue gas and from the data center. The CO.sub.2 rich streams from the post combustion capture system are sent to sequestration of some form via a sequestration compressor, thereby reducing the overall emissions from the facility.

Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydroxychloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.

The plant according to the invention includes a reactor including a combustion chamber in which a fuel is fired with an oxidant to form a carbon dioxide-containing flue gas stream. The plant also includes a waste heat recovery unit in fluid connection with the combustion chamber, configured to capture heat from the flue gas stream. The plant also includes a flue gas compression unit in fluid connection with the waste heat recovery unit, configured to increase the pressure of the flue gas stream. The plant also includes a scrubber in fluid connection with the flue gas compression unit, configured to remove sulphur oxides and/or nitrogen oxides from the flue gas stream and to cool flue gas stream by means of the scrubbing medium. The plant also includes an absorption unit in fluid connection with the scrubber, configured to absorb carbon dioxide from the flue gas stream.