An exhaust gas treatment apparatus includes: a second reductant supply part, disposed in a flow path of combustion exhaust gas of a fuel containing a first reductant that is capable of reducing a specific substance, for supplying a second reductant for reducing the specific substance in the combustion exhaust gas to the combustion exhaust gas; and a first reductant decreasing part, disposed upstream of the second reductant supply part in the flow path, for decreasing the first reductant in the combustion exhaust gas.

A process for combusting a high-moisture fuel to generate steam in which the high-moisture solid fuel is first dried by contacting with an oxygen-depleted gas stream while being heated by indirect heat exchange with a recirculating thermal fluid. The dried fuel is then combusted with a combustion air stream to produce a combustion products stream whose heat first is used to generate steam, and then to preheat the combustion air stream by indirect heat exchange in which a portion of the combustion air stream and/or a portion of the combustion products stream bypasses the heat exchanger. The combustion products stream also provides heat to dry the solid fuel via the recirculating thermal fluid.

A process for combusting a high-moisture fuel to generate steam in which the high-moisture solid fuel is first dried by contacting with an oxygen-depleted gas stream while being heated by indirect heat exchange with a recirculating thermal fluid. The dried fuel is then combusted with a combustion air stream to produce a combustion products stream whose heat first is used to generate steam, and then to preheat the combustion air stream by indirect heat exchange in which a portion of the combustion air stream and/or a portion of the combustion products stream bypasses the heat exchanger. The combustion products stream also provides heat to dry the solid fuel via the recirculating thermal fluid.

A CO2 capture system includes an intake for CO2-rich exhaust gas to a compressor and one or more outlets for compressed, first CO2-rich gas to a manifold to a shell enclosing parts of a combustion chamber. The combustion chamber has burners to burn fuel and compressed air from a fuel line and an air supply pipe, to form a second, CO2 rich gas. The wall in the combustion chamber has slits to let in the compressed CO2-rich gas to mix with and cool the other CO2-rich gas formed in the combustion chamber of a third CO2-rich exhaust gas. A heat exchanger operates under high pressure and heat exchanges the third, hot CO2-rich exhaust gas from the combustion chamber with returning CO2-poor exhaust gas from a CO2 extraction plant. The returned, heated CO2-poor exhaust gas is led back to an expander driving the compressor and the CO2 extraction plant.

Several embodiments of the present technology are directed to the removal of one or more air pollutants using cooling and/or calcium-containing particles. In some embodiments, a method for removing air pollutants comprises flowing a gas stream having calcium-containing particles and one or more of mercury or hydrochloric acid molecules, and cooling the gas stream, thereby causing at least a portion of the calcium-containing particles to adsorb to the mercury and/or hydrochloric acid molecules in the gas stream. The method can further comprise, after cooling the gas stream, filtering the gas stream to remove at least a portion of the calcium-containing particles having adsorbed mercury and hydrochloric acid.

A method for removing noxious, hazardous, toxic, mutagenic, and/or carcinogenic compounds and/or precursor compounds from a comingled gas, liquid, and/or solid stream is described. In one embodiment, the method is used to prepare the stream for feeding to an oxidizer, such as a thermal oxidizer, to reduce the amount of particulate matter discharged by the oxidizer and includes passing the stream through an ambient or chilled temperature condenser followed by an optional gas/solid separator, and one or more gas scrubbers prior to feeding to the oxidizer.

The present invention is generally related to a system and method that efficiently and effectively removes mercury, dioxin, and furan while also reducing granule activated carbon (GAC) bed fires on high temperature municipal fluid bed sludge incinerators. In this manner, the United States Environmental Protection Agency (EPA) Maximum Achievable Control Technology LLLL (MACT LLLL) emission limits on mercury, dioxin, and furans can be met for new high temperature fluid bed municipal sludge incineration plants, while the likelihood of GAC fires can be reduced.