Mitsubishi Heavy Industries Limited

Mitsubishi Hitachi Power Systems, Ltd.

Akita University

Itsubishi Heavy Industries, Ltd.

Masashi Kiyosawa

Katsumi Nochi

Yoshiaki Obayashi

Masanori Demoto

Kozo Iida

Masanao Yonemura

Shigeru Nojima

Shintaro Honjo

Norihisa Kobayashi

Kiyonori Kushioka

Hideo Miyanishi

Manabu Oda

Toshihiro Sato

Yoshiaki Ito

Nobuyuki Ukai

Moritoshi Murakami

Kazuhisa Takeuchi

Shimpei Todaka

Rikuma Shijo

Nobuyasu Sakata

Tomotsugu Masuda

Ryo Kamito

Hiroshi Kako

Shinpei Kaneda

Kyohei Takakura

Katsuyasu Sugawara

Yuuki Mochizuki

Koichi Yokoyama

Keiichiro Kai

Disclosed is a system for producing magnesium hydroxide including: a generation unit; and a recovery unit connected to the generation unit, wherein the generation unit has a reaction tank in which a calcium hydroxide slurry is added to water to be treated containing magnesium ions to crystallize magnesium hydroxide and to obtain a reaction slurry containing particles of magnesium hydroxide, and a sedimentation tank in which the reaction slurry is reserved to sediment the particles and to separate the reaction slurry into a separation slurry containing the particles at a high concentration and a separation liquid containing the particles at a low concentration, and wherein, in the recovery unit, an alkaline aqueous solution is added to the separation liquid to crystallize magnesium hydroxide and to obtain the reaction slurry and then the reaction slurry is reserved to sediment the particles and to recover the sedimented particles.

System for producing magnesium hydroxide

A system for producing a magnesium chloride aqueous solution includes a crystallization unit configured to generate reaction slurry in which particles of magnesium hydroxide are dispersed by adding a sodium hydroxide aqueous solution to water to be treated, a precipitation unit configured to store reaction slurry, precipitate particles and separate the reaction slurry into recovered slurry and a separated liquid, a removal unit configured to remove divalent cations from the water to be treated or the separated liquid to generate a reaction liquid, an acid-alkali generation unit configured to generate a sodium hydroxide aqueous solution and hydrochloric acid from the reaction liquid, and a reaction unit configured to generate a magnesium chloride aqueous solution by adding hydrochloric acid to the recovered slurry. The acid-alkali generation unit has a main body section configured to generate a sodium hydroxide aqueous solution and hydrochloric acid from the reaction liquid.

System for producing magnesium chloride aqueous solution and system for producing magnesium

A plate-shaped chemical heat storage comprising a substrate composed of a net made of metal and a heat storage material composition supported on the substrate, wherein the heat storage material composition comprises at least one selected from the group consisting of magnesium hydroxide or oxide, strontium hydroxide or oxide, barium hydroxide or oxide, calcium hydroxide or oxide, and calcium sulfate, and optionally at least one selected from the group consisting of titanium dioxide, silicon dioxide, alumina silicate fiber, E-glass fiber and cellulose.

Platy chemical heat-storage object

Provided is a duct wall surface structure which, in a flue of an iron-sheet duct with a hopper through which a solid-gas two-phase stream flows, can enhance the solid particle trapping efficiency of the hopper and reduce the outflow of the solid particles to the duct downstream side. The duct wall surface structure of a flue () through which a solid-gas two-phase stream containing large-diameter ash () flows includes a first hopper (A) installed at the lower end of a first vertical flue section (), installed in such a direction that the stream has a vertical component of velocity, to collect the large-diameter ash () from the stream, wherein a low-rebound part () having a lower coefficient of restitution than an iron sheet is provided on an inclined surface (), with which the large-diameter ash () collides, on the upstream side in the flow direction from the first hopper (A).

Duct wall surface structure

In an exhaust duct and a boiler, there are provided: a flue gas duct through which flue gases pass; a first hopper provided to the flue gas duct, the first hopper collecting PA in the flue gases; a low-repulsion section provided to the upstream side or the downstream side of the first hopper in the direction of flow of the flue gases, the low-repulsion section having a lower coefficient of repulsion than the inner wall surface of the flue gas duct; and a popcorn-ash-trapping section for trapping PA in the flue gases, the popcorn-ash-trapping section provided to the downstream side of the first hopper and the low-repulsion section in the direction of flow of the flue gases, whereby it is possible for solid particles in the flue gases to be properly trapped.

Exhaust duct and boiler

An exhaust duct and boiler can appropriately collect solid particles in flue gas by way of being provided with: a flue () in which flue gas can flow; a first hopper () that is provided in the flue () and that can collect solid particles (PA) in the flue gas; and a first baffle plate () and a second baffle plate () that are resisting members capable of blocking the flow of solid particles (PA) from the first hopper ().

A boiler system is provided including: a boiler that burns fuel containing sulfur content, chlorine content, and water content to generate a combustion gas; a bagfilter that removes sulfur oxide; a denitration section that removes nitrogen oxide; a desulfurizing absorbent supply section that mixes a desulfurizing absorbent into the combustion gas on an upstream side of the bagfilter; and a reformer that mixes a denitrating reagent into the combustion gas on an upstream side of the denitration section, wherein the bagfilter performs dry desulfurization, and a temperature of the combustion gas passing through the bagfilter and flowing into the denitration section is higher than 200&#xb0; C. and 350&#xb0; C. or lower, and the combustion gas from which the sulfur oxide has been removed by the bagfilter flows into the denitration section without being heated on the upstream side of the denitration section.

Boiler system and power plant including the same

Provided are an exhaust gas treatment catalyst for denitrifying an exhaust gas including sulfur oxides and vanadium discharged from a heavy oil combustion boiler, including: a support comprising any one or all of titanium oxide and silica wherein a content of silica is from 10% to 20%, and an active component supported in the support and comprising one selected from the group consisting of vanadium and tungsten.

Exhaust gas treatment catalyst

Provided is a practical method for dry-separating arsenic compounds from a used NOx removal catalyst contaminated with arsenic. The method for removing arsenic compounds comprises heat-treating a NOx removal catalyst contaminated with arsenic compounds at a predetermined temperature in a reducing atmosphere while exposing the catalyst to hydrocarbon compounds (except CH) or oxygen-containing carbon compound.

Apparatus for removing arsenic compound

In a NOremoval catalyst used for removing nitrogen oxides in flue gas, when a silica (Si) component as an inhibitor that causes an increase in a SOoxidation rate accumulates on a surface of the catalyst, the silica component accumulating on the surface of the catalyst is dissolved, thereby regenerating the catalyst. Accordingly, the inhibitor such as the silica component covering the surface of the NOremoval catalyst can be removed, thereby enabling to provide a catalyst without having an increase in the SOoxidation rate of the regenerated NOremoval catalyst.

[object Object]

Provided is an exhaust gas treatment catalyst including: a de-NOx catalyst; and a coating layer being provided on a surface of the de-NOx catalyst and containing at least one selected from the group consisting of alkali metal carbonates and alkaline earth metal carbonates. In a method for regenerating an exhaust gas treatment catalyst of the present invention, the coating layer of the de-NOx catalyst on which VOSOis deposited is removed with an acid, and after the removal of the coating layer, a coating layer containing at least one selected from the group consisting of alkali metal carbonates and alkaline earth metal carbonates is again provided.

Method for regenerating exhaust gas treatment catalyst

The method includes a pretreatment step during an operation of a boiler in which in a predetermined period of time before shutdown of the boiler, a part of combustion gas that has bypassed an economizer provided in a flue gas duct for flue gas from the boiler is supplied to an upstream of a NOremoval device having a NOremoval catalyst and mixed with the combustion flue gas from the economizer to generate mixed gas having a predetermined temperature equal to or higher than 360&#xb0; C. (360&#xb0; C. to 450&#xb0; C.), the mixed gas is introduced into the NOremoval catalyst, thereby decomposing VOSOadhering to and accumulating on the NOremoval catalyst into VO.

Exhaust gas treatment catalyst and method for regenerating the same

Method for removing arsenic compound, method for regenerating NOx removal catalyst, and NOx removal catalyst

A separation and recovery method that enables titanium and tungsten to be separated and recovered from a used DeNOx catalyst in high yield. Specifically, a method of separating and recovering metal elements that includes a first heating step of heating a DeNOx catalyst containing titanium, tungsten, vanadium and iron in a chlorine atmosphere, thereby removing the vanadium and the iron from the DeNOx catalyst, and a second heating step, performed after the first heating step, of heating the DeNOx catalyst in a chlorine atmosphere while the catalyst is exposed to a gas of a hydrocarbon compound (excluding CH) or an oxygen-containing carbon compound, thereby volatilizing the tungsten and the titanium from the DeNOx catalyst, and recovering the tungsten and the titanium from the DeNOx catalyst.

Growing community of inventors

Tokyo, Japan

Masashi Kiyosawa