A promoted carbon and/or non-carbon base sorbent are described that are highly effective for the removal of mercury from flue gas streams. The promoted sorbent comprises a carbon and/or non-carbon base sorbent that has reacted with and contains forms of halogen and halides. Optional components may be added to increase and/or preserve reactivity and mercury capacity. These may be added directly with the base sorbent, or in-flight within a gas stream (air, flue gas, etc.), to enhance base sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The promoted sorbent can be regenerated and reused. Base sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active base sorbent into the mercury contaminated gas stream are described.

The present application provides a method of treating flue gas in a duct with an injection system, the flue gas comprising an acid gas and/or one or more metal components, the injection system comprising at least one injection nozzle in communication with an air supply and a supply of sorbent; wherein the method comprises supplying air and sorbent through the nozzle to the duct such that the penetration of the sorbent into the duct is represented by the formula: Y=(D.sub.na(p.sub.nV.sub.n.sup.2/p.sub.fV.sub.f.sup.2).sup.0.5(x/D.sub.n).sup.0.33)/D.sub.f where Y is the fraction of duct penetration depth of the sorbent when the duct length is x, D.sub.n is the diameter of the nozzle, D.sub.f is the depth of the duct, p.sub.n and p.sub.f are the densities of the air supply and flue gas, respectively V.sub.n and V.sub.f are the velocities of the air exiting the nozzle and the flue gas, respectively, and where a is between 0.3 and 1.0 and where Y is between 0.3 and 0.8.

Process for treating a gas contaminated by at least one element selected from the group consisting of heavy metals, organic compounds, and combinations thereof, wherein a calcium-phosphate reactant (reagent) particle comprising apatite is brought into contact with the contaminated gas at a temperature of at least 30 C. and preferably at most 1100 C. The metal(s) and/or organic compound(s) to be removed from the contaminated gas may be selected among the list of: Al, Ag, As, Ba, Be, Bi, Ce, Co, Cd, Cu, Cr, Fe, Hf, Hg, La, Li, Mg, Mn, Mo, Ni, Pb, Pd, Rb, Sb, Se, Sn, Sr, Th, Ti, U, V, Y, Zn, Zr, VOC, aromatic compounds, PAHs, dioxins, furans, or any mixture thereof. In such process, an alkaline compound particle comprising sodium bicarbonate, sodium carbonate, sodium sesquicarbonate (trona), quick lime, hydrated lime, lime stone or combinations thereof, may be further brought into contact with the contaminated gas.

An injection lance assembly for creating a higher degree of turbulence and dispersion of a treating agent into a fluid stream.

The invention includes systems, methods, compositions, and processes for designing, manufacturing, and utilizing carbon dioxide-sequestering substrates that can fully or partially replace natural sand in coastal engineering applications. These engineered substrates can offset demand for scarce native sand resources, while also effecting the conversion of gaseous carbon dioxide to dissolved or solid-phase products thereby offsetting impacts of anthropogenic climate change.

A multi-function duct for a dry scrubber system useful for processing a gas stream, such as a flue gas stream produced by a fossil fuel fired boiler, a combustion process or the like, is provided. The multi-function duct is useful for a circulating dry scrubber (CDS) dry flue gas desulfurization (DFGD) system operable for dry or moistened reducing agent distribution into a flue gas stream flowing therethrough. As such, the distributed dry or moistened reducing agent reacts with acid gas in the flue gas to produce a dry reaction product.

The combustion and flue gas treatment system includes a furnace for combusting a fuel with an oxidizer generating a flue gas, ducting for the flue gas connected to a NO.sub.x removal unit and a SO.sub.x removal unit, and a recirculation line for recirculating a part of the flue gas back to the furnace. The SO.sub.x removal unit is located upstream of the NO.sub.x removal unit with reference to the flue gas flow. The recirculation line is connected to the ducting downstream the SO.sub.x removal unit.

A desulfurization and denitration method includes adding an aqueous solution of a chlorate, an aqueous solution of a peroxide, and an aqueous solution of sulfuric acid to a chlorine dioxide generator to obtain gaseous chlorine dioxide, and mixing the gaseous chlorine dioxide with air to obtain a mixed gas. The gaseous chlorine dioxide is 4-10 vol % of the mixed gas. The method includes letting the mixed gas come into contact with a flue gas to obtain an oxidized flue gas. A molar ratio of the gaseous chlorine dioxide in the mixed gas to nitric oxide in the flue gas is 1-1.8. The final step includes passing the oxidized flue gas to the desulfurization and denitration tower and mixing the oxidized flue gas with a spray of an alkaline absorbent dry powder, and spraying water into the desulfurization and denitration tower to obtain a desulfurized and denitrated flue gas.

The system and method for preventing air leakage from the process side to the bearing side of a mill. The system includes a labyrinth seal ring comprising a series of knives defining first and second labyrinth paths from an air inlet to the process side and the bearing side of the system, respectively. The differences in the two paths such as provided by the number of knives used in each path creates a differential pressure drop which biases air from the air inlet to the process side. The labyrinth seal thus provides a reliable and superior method for reducing the potential for particulate in the process side of the mill from damaging the bearing system.

A dry scrubbing system and process wherein an acid gas comprising at least one pollutant is modified in a humid zone of a duct such that a relative humidity of between 2% and 90% is achieved. The humidified gas is then contacted with chalked lime in a reaction zone. The reaction zone components are subsequently filtered in a filtering zone to provide a filtered gas having reduced concentration of the at least one pollutant when compared to the initial acid gas.