A modified natural sulfide ore material, a preparation method, and a use thereof are disclosed. A natural sulfide ore and a copper salt are used as raw materials. The natural sulfide ore is modified through mechanical grinding for activation, drying, and the like to synthesize a sulfide ore composite. The copper salt is subjected to a reaction to increase metal sites, produce fine microcrystalline particles, and change the crystal structure, such that active sites can be fully exposed. When contacting mercury in a gas phase and/or a liquid phase, the modified natural sulfide ore material can convert the mercury into a stable compound to realize the immobilization and removal of the mercury, which has advantages such as large mercury adsorption capacity, high adsorption rate, wide application temperature range, low cost, abundant raw material reserves, simple operation, and environmentally-friendly mercury removal products without secondary pollution and shows promising industrial application prospects.

The present disclosure generally relates to a denitration catalyst, and in particular to a method for preparing the denitration catalyst. The present disclosure also relates to a method for preparing a coated substrate comprising the denitration catalyst. The present invention also relates to use of the denitration catalyst and/or coated substrate at low temperatures and/or humid environments.

A powdered catalyst material on a titanium oxide basis. The powdered catalyst material includes a combined content of at least 90 wt.-% of a hydrated titanium oxide having the general formula TiO.sub.(2-x)(OH).sub.2x, with 0<x≤1, (calculated as TiO.sub.2), and a silicon dioxide and hydrated precursors of the silicon dioxide (calculated as SiO.sub.2). A weight ratio of TiO.sub.2/SiO.sub.2, determined for TiO.sub.2 and SiO.sub.2 respectively, is at least 3 and less than 30. The wt.-% is based on a total weight of the catalyst material after the catalyst material has been dried at 105° C. for at least 2 hours. The powdered catalyst material has a specific surface area of >300 m.sup.2/g and an isoelectric point of from 4.0 to 7.0.

A carbon dioxide recovery apparatus is disclosed including a flue gas cooling unit that brings flue gas cooling water into contact with a flue gas to cool the flue gas, a circulation channel through which the flue gas cooling water and condensed water are returned to the flue gas cooling unit, an absorption unit including a carbon dioxide absorbing section, and a flue gas washing section that brings the flue gas including carbon dioxide absorbed in the carbon dioxide absorbing section into contact with flue gas washing water and washes the flue gas, a regeneration unit that removes carbon dioxide from the absorbent including carbon dioxide absorbed in the absorption unit, a supply channel through which circulating water is guided, and a discharge channel through which the circulating water circulating through the flue gas cooling unit and the circulation channel is discharged to outside of a system.

A method and apparatus for purifying gas where gas is treated in a multistage treatment having at least two ejector stages, a motive medium including liquid, steam or gaseous agent at high pressure injected by an ejector of the ejector stage, and the gas is sucked into the same ejector and mixed with the motive medium for forming a mixture, at least a part of gas and/or liquid phase of the mixture is supplied to a second ejector stage having so that a second motive medium which includes liquid, steam or gaseous agent is injected to the ejector and the gas and/or the liquid phase is sucked into the same ejector in which the gas and/or liquid phase is mixed with the second motive medium for forming a second mixture, at least one of the mixtures includes an additive for removing impurities of the gas, and a purified gas is formed.

A system for treating exhaust gas generated by combustion of biomass comprises a frame, a first cyclonic separation stage supported on the frame and comprising a plurality of parallel gas cyclones in fluidic communication with an inlet receiving the exhaust gas for removing from the exhaust gas particulate matter exceeding a first threshold size, and a second bag filtration stage supported on the frame and comprising a plurality of serially-communicated baghouses each comprising a plurality of bag filters therein for removing, from the partially treated exhaust gas received from the first cyclonic separation stage, particulate matter exceeding a second threshold size that is smaller than the first size which was passed through the first treatment stage. The gas cyclones of the first stage are arranged in a laterally extending row across the frame and the baghouses are arranged in a longitudinally extending row across the frame.

A catalyst arrangement deciding method for a flue gas denitrizer including a catalyst layer disposed in an exhaust gas passage includes: a step of investigating a location dependence of a degradation state of a catalyst in the catalyst layer after a lapse of a period of operation; and a step of deciding a first region of the catalyst layer in which a first catalyst is used and a second region of the catalyst layer in which a second catalyst different from the first catalyst is used, on the basis of the location dependence.

A reclaimer system and methods for using said reclaimer system to reclaim one or more amine agents from a fluid containing one or more degradation products that have been formed from the reaction of one or more acid gas components with the one or more amine agents.

A method includes collecting exhaust gas comprising carbon dioxide (CO.sub.2) at a wellsite to provide a collected exhaust gas, separating CO.sub.2 from the collected exhaust gas to provide a separated CO.sub.2, and forming urea utilizing at least a portion of the separated CO.sub.2. A system for carrying out the method is also provided.

Described herein is a dry sorbent injection system and process for removing sulfur oxides from a flue gas. The process generally comprises treating the flue gas with a dry sorbent material to convert the sulfur oxides to sodium sulfate particulates. The sodium sulfate particulates may then be introduced into a mix tank with water to form sodium sulfate solution. The sodium sulfate solution may then be reacted with a calcium hydroxide slurry to produce a reaction mixture comprising calcium sulfate precipitate and a sodium hydroxide solution. The calcium sulfate (gypsum) may be recovered, and the sodium hydroxide solution may be recirculated to pre-treat the flue gas by removing at least a portion of the sulfur dioxide and/or cooling the flue gas stream.