A desulfurization wastewater zero discharge treatment method and system suitable for multiple working conditions. A tail flue of a boiler and a bottom outlet of a wastewater drying tower are both communicated with an inlet of a dust collector; an outlet of the dust collector is communicated with flue gas inlets of a wastewater concentration tower and a desulfurization absorption tower; the wastewater concentration tower is communicated with the desulfurization absorption tower; the desulfurization absorption tower is communicated with a chimney; the desulfurization absorption tower is communicated with a gypsum cyclone; the gypsum cyclone is communicated with a filtrate water tank; the gypsum cyclone is communicated with a gypsum dewatering machine; the gypsum dewatering machine is communicated with a gas liquid separating tank; and a flue gas port of the tail flue of the boiler is communicated with the flue gas inlet of the wastewater drying tower.

A spray dryer absorber operative for removing gaseous pollutants from a hot process flue gas and a vibrator device for removing accumulated deposits therefrom is provided. The spray dryer absorber includes a spray dryer chamber equipped with a plurality of dispersers and atomizers mounted at a roof of the spray dryer chamber. The vibrator device is operative to remove accumulated deposits from the spray dryer absorber and its components, such as its dispersers and atomizers, to avoid spray dryer absorber performance interference caused by such deposit accumulations.

The invention relates to a reactor for cleaning flue gases by a dry or quasi-dry sorption process, comprising a flue gas inlet (1) at the bottom of the reactor, an outlet (2) at the top of the reactor, a dry sorbent injection system (3) with at least one dry sorbent outlet (4) for injecting dry sorbent into the reactor, the at least one dry sorbent outlet (4) being arranged between the flue gas inlet (1) and the outlet (2).

Methods and systems for control and adjustment of the feed rate of mercury reemission control additives (MECA) to a wet flue gas desulfurization system. Predetermined sulfite concentration values are compared to actual sulfite concentrations measured in the scrubber liquid. The MECA feed to the recirculating scrubber liquor is then adjusted and regulated as a result of such comparisons.

Methods and systems for control and adjustment of the feed rate of mercury reemission control additives (MECA) to a wet flue gas desulfurization system. Predetermined sulfite concentration values are compared to actual sulfite concentrations measured in the scrubber liquid. The MECA feed to the recirculating scrubber liquor is then adjusted and regulated as a result of such comparisons.

A spray dryer absorber (SDA) system used to reduce the concentration of at least one acid compound in a gas utilizes low or no alkali-containing particulate compounds to prevent cementing during operation. The low or no-alkali-containing compounds may be supplied from external sources and/or from a particulate collection device located downstream of the SDA.

The description relates to a process for reducing acid plume from stacks from coal-fired combustors operating at varying loads, which have typically been treated by back-end calcium carbonate (limestone) which has not been able to effectively control visible acid plume as power is ramped up from low load. According to the process, as high sulfur and high iron coals are burned in a combustor, magnesium hydroxide slurry is introduced into hot combustion gases in or near the combustion zone. And, during ramp up to high load from a period of operation at low load, additional magnesium hydroxide is introduced into an intermediate-temperature zone.

A method of reducing sulfur dioxide emissions of a circulating fluidized bed boiler plant. A first stream of sulfur-containing carbonaceous fuel is fed at a first feeding rate to a furnace of the boiler. A second stream of calcium carbonate containing absorbent having a predetermined d50 particle size is fed at a second feeding rate to the furnace. Oxygen containing gas is fed to the furnace for fluidizing a bed of particles forming in the furnace. Fuel is combusted with the oxygen and the sulfur in the fuel is oxidized to sulfur dioxide. The calcium carbonate is calcined to calcium oxide in the furnace. A portion of the calcium oxide is used to sulfate a first portion of the sulfur dioxide to calcium sulfate in the furnace.

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.

A method of reducing sulfur dioxide emissions of a circulating fluidized bed boiler plant. A first stream of sulfur-containing carbonaceous fuel is fed at a first feeding rate to a furnace of the boiler. A second stream of calcium carbonate containing absorbent having a predetermined d50 particle size is fed at a second feeding rate to the furnace. Oxygen containing gas is fed to the furnace for fluidizing a bed of particles forming in the furnace. Fuel is combusted with the oxygen and the sulfur in the fuel is oxidized to sulfur dioxide. The calcium carbonate is calcined to calcium oxide in the furnace. A portion of the calcium oxide is used to sulfate a first portion of the sulfur dioxide to calcium sulfate in the furnace.