Abstract: A method of sequestering gaseous carbon dioxide in which an oxide is carbonated by contacting it with a first aqueous carbonate solution to convert a portion of the oxide into a carbonate, which precipitates from solution. By converting the oxide to a solid carbonate, the CO2 from the first carbonate solution is sequestered into the precipitate. At the same time, an aqueous hydroxide solution is formed. The aqueous hydroxide solution is contacted with gaseous carbon dioxide which sequesters the gaseous CO2 into a second aqueous carbonate solution. The second solution so generated is then recycled back into the process and used to convert the oxide into the precipitated carbonate.

Abstract: The present disclosure provides an automatic control system for emission indexes of a desulfurization device of a thermal power unit, which comprises a first controller, a second controller and a flow controller. At the same time, the present disclosure provides an automatic control method for emission indexes of a desulfurization device of a thermal power unit. The present disclosure runs through the production and operation data of waste gas desulfurization treatment facilities, and establishes a pH optimization set value prediction model according to the data, and can realize automatic regulation and control of pH value by optimizing and controlling the pH optimization set value and the slurry flow optimization set value every moment through the dynamic model, thus solving the problem that the pH value control process is large in lag and slow in dynamics, and improving the pH value control quality.

Abstract: The operation of wet scrubbers, especially those based on calcium carbonate, is improved by reducing the quantities of soluble chlorides in the combustion gases fed to the scrubbers. HCl in the combustion gases is converted to a solid copper chloride and removed before the chloride reaches the scrubber. Combustion gases are treated with an aqueous copper compound referred to as copper-bearing chloride remediator (CBCR). Effective temperatures for introducing the CBCRs are preferably within the range of from about 250° to 900° F. Among the more preferred CBCRs are copper compositions including copper, an organic moiety and/or an ammonia moiety.

Abstract: A method and apparatus for converting an iron-bearing residue generated in a hydrometallurgical process that contains small amounts of soluble heavy metals into a stable form by means of a neutralizing agent. The residue is elutriated and the elutriated residue is fed into at least one stabilization or homogenization reactor, into which a neutralizing agent is also routed, and the homogenous mixing together of the residue and neutralizing agent takes place by means of a helix mixer, where the ratio of the diameter of the mixer to the diameter of the reactor is 0.75-0.99.

Abstract: A treatment system to efficiently remove lead from dust contained in extracted cement kiln combustion gas while reducing facility and running costs. A treatment system 1 comprising: a probe 3 for extracting a part of combustion gas, while cooling it, from a kiln exhaust gas passage, which runs from an inlet end of a cement kiln to a bottom cyclone; a classifier 5 for separating coarse powder from dust contained in the combustion gas extracted by the probe 3; a wet dust collector 6 for collecting dust from the extracted gas containing fine powder discharged from the classifier 5; and devices 12, 13 for feeding sulfurizing agent for sulfurizing lead contained in the kiln exhaust gas to the wet dust collector 6, and others. From the sulfurizing-agent feeders 12, 13 are preferably added the sulfurizing agents to a circulation liquid tank 7 or a pump 9 for circulating slurry.

Abstract: Processes comprising: providing a crude gas comprising hydrogen chloride and at least one sulfur compound; and passing the crude gas across a sacrificial material such that at least a portion of the at least one sulfur compound is oxidized and precipitated as sulfate onto the sacrificial material to provide a hydrogen chloride product gas.

Abstract: A method for removing impurities accumulated in a scrubbing fluid in a flue gas scrubber and effluents from the scrubber. The flue gases are scrubbed with a scrubbing fluid that includes a calcium-containing absorbent. The scrubbing fluid containing gypsum and other impurities and produced in the scrubber is discharged from the scrubber. The gypsum is separated from the scrubbing fluid. To the scrubbing fluid is added an auxiliary agent, by the effect of which the impurities accumulated in the scrubbing fluid are removed with the gypsum and the moisture content of the gypsum to be separated from the scrubbing fluid is increased.

Abstract: A process is provided for the removal of mercury and sulfur dioxide out a flue gas from, for example, power stations, smelters, waste incineration plants and crematories, by washing the flue gas with an oxidized, chloride-containing washing water, which may be sea water, which has been oxidized by either adding an oxidizing agent, such as sodium hypochlorite, or by passing an electric current through the washing water (which converts the chloride values into chlorine) so that the gaseous mercury is sorbed into the washing water and is converted into mercury (II) chloride complexes and the gaseous sulfur dioxide is sorbed into the washing water and converted into sulfuric acid, and subsequently passing the resulting mercury (II) chloride and sulfuric acid-containing washing water and the flue gas through a bed of calcium carbonate where the sulfuric acid and the calcium carbonate react to form calcium sulfate which is washed off the bed into the washing water.