Nippon Shokubai Co., Ltd.

Taiheiyo Cement Corporation

Shinyuki Masaki

Noboru Sugishima

Motonobu Kobayashi

Atsushi Morita

Ryoji Kuma

Shinichiro Saito

Junichi Terasaki

Junji Okamura

Hisashi Kondo

Yasuhiro Uchiyama

Mitsuharu Hagi

Futoru Kinoshita

Jyunichiro Kugai

Hisao Kondo

A combustion exhaust gas processing device comprises: a dust collector collecting dust in a cement kiln combustion exhaust gas; a wet dust collector using sodium hypochlorite as a catalyst-poisoning-substance stripper for removing a catalyst-poisoning substance and mercury from a combustion exhaust gas which passed the dust collector; heaters downstream of the wet dust collector for heating the combustion exhaust gas from the wet dust collector; and a catalyst device from which NOx, a persistent organic pollutant, etc. in the heated combustion exhaust gas, are removed. An upstream side of the catalyst device is installed with an oxide catalyst such as titanium-vanadium and a downstream side is installed with a platinum catalyst as a noble-metal catalyst. The temperature of the combustion exhaust gas after the wet dust collector is increased up to 140&#xb0; C. or more with the heaters to prevent decline in denitration efficiency of and the decomposition efficiency of a volatile organic compound. A mercury adsorbing tower is provided for adsorbing the mercury in liquid exhausted from the wet dust collector and wastewater from the liquid is used to generate sodium hypochlorite for use in the wet dust collector.

Device and method for processing cement kiln combustion exhaust gas

A combustion exhaust gas processing device comprises: a dust collector collecting dust in a cement kiln combustion exhaust gas: a wet dust collector as a catalyst-poisoning-substance stripper removing a catalyst-poisoning substance from a combustion exhaust gas which passed the wet dust collector; and a catalyst device from which NOx, a persistent organic pollutant, etc. in the preheated combustion exhaust gas, are removed. A titanium-vanadium catalyst etc. as an oxide catalyst is used upstream of the catalyst device, and a platinum catalyst etc. as a noble-metal catalyst downstream of the catalyst device. The temperature of the combustion exhaust gas after the catalyst-poisoning substance is removed is increased up to 140&#xb0; C. or more with the preheaters to prevent decline in denitration efficiency of and the decomposition efficiency of a volatile organic compound.

Device and method for processing cement kiln combustion exhaust

A catalyst for treating exhaust gases having excellent durability and performance for removing nitrogen oxides and organic halogen compounds and a low SOoxidation rate, a titanium oxide suitable for preparing the catalyst and a method for treating exhaust gases containing nitrogen oxides and/or organic halogen compounds using the catalyst are provided. The BET specific surface areas of the titanium oxide and the catalyst for treating exhaust gases are in the range of 85 to 250 m/g and in the range of 50 to 200 m/g respectively. The titanium oxide and the catalyst for treating exhaust gases have each a ratio in the range of 15 to 145%, the ratio of the intensity of the peak indicating an anatase crystal present in the range of 2&#x3b8;=24.7&#xb0; to 2&#x3b8;=25.7&#xb0; of powder X-ray diffraction thereof (Ia) to the intensity of the peak indicating an anatase crystal present in the range of 2&#x3b8;=24.7&#xb0; to 2&#x3b8;=25.7&#xb0; of powder X-ray diffraction of the standard sample comprising a mixture composed of 15% by mass of pure anatase-type titanium dioxide and 85% by mass of pure rutile-type titanium dioxide (Ib).

Titanium oxide, catalyst for treating exhaust gas and method for purifying exhaust gas

The present invention has an object to more enhance the efficiency of the purification of the CO-containing exhaust gases with a catalytic-component-supporting type catalyst, particularly, to enable both achievement of high purification efficiency and long-term stable maintenance of high purification efficiency without increasing the quantity of the catalytic component as supported. As a means of achieving this object, a process for purification of exhaust gases, according to the present invention, is a process for purification of exhaust gases to remove CO therefrom, and is characterized by comprising the step of bringing the exhaust gases into contact with a catalyst layer at a temperature of 250 to 600&#xb0; C., a pressure drop of not more than 100 mmHO, and a linear velocity of 0.5 to 10 m/s, wherein the catalyst layer includes a honeycomb-structural catalyst having an opening size of 1.0 to 3.0 mm, an opening ratio of 60 to 80%, and an inner wall thickness of less than 2 mm.

Process for purification of exhaust gases and catalyst used for purification of exhaust gases in this process

An object of the present invention is to provide a new method for treating an exhaust gas, which can effectively treat an exhaust gas containing a nitrogen oxide and metal mercury over a long term, and also can be applied to treatment of a large volume of an exhaust gas. As a means of achieving this object, a method according to the present invention for treating an exhaust gas comprises performing a reaction of changing metal mercury into mercury halide in the presence of a halogen compound and treatment of a nitrogen oxide, using a Ti&#x2014;V-containing catalyst, upon treatment of an exhaust gas containing a nitrogen oxide and metal mercury.

Method for treating exhaust gas

A catalyst for purification of CO-containing exhaust gases, includes a metal oxide as a support and a catalytic component A being supported thereon as a catalytic component and including a specific noble metal element; wherein the support includes a titanium-containing oxide as the metal oxide and is a monolithically molded type porous honeycomb support obtained by a process including the steps of extrusion-molding and then calcining materials of the support; and wherein the catalytic component A is distributed with a quantitatively great inclination toward surfaces of the catalyst. A process for purification of exhaust gases to remove CO therefrom, includes the step of bringing the exhaust gases into contact with the catalyst.

Catalyst for purification of exhaust gases and process for purification of exhaust gases

The present invention provides: a catalyst for purification of exhaust gases which catalyst is excellent as a denitrification catalyst which has still more excellent ability to remove nitrogen oxides and of which the ability to oxidize sulfur dioxide into sulfur trioxide is extremely suppressed and further as a catalyst which is favorable for efficiently removing organohalogen compounds, such as dioxins, from exhaust gases; a production process therefor; and a process for purification of exhaust gases. The catalyst for purification of exhaust gases comprises titanium oxide, molybdenum oxide, and vanadium oxide as catalytic components, wherein the titanium oxide and the molybdenum oxide are included in the catalyst in the form of: a binary closely mixed oxide which is beforehand prepared and includes titanium and molybdenum; and/or a trinary closely mixed oxide which is beforehand prepared and includes titanium, silicon, and molybdenum.

Catalyst for purification of exhaust gases, production process therefor, and process for purification of exhaust gases

The present invention provides: a catalyst which has more excellent removability upon organohalogen compounds and is suitable for removing the organohalogen compounds from exhaust gases; and a process for removing organohalogen compounds with this catalyst. The catalyst for removing organohalogen compounds comprises titanium oxide (TiO) and vanadium oxide as catalytic components, and has pores that includes a group of pores having a pore diameter distribution peak in the range of 0.01 to 0.05 &#x3bc;m and another group of pores having a pore diameter distribution peak in the range of 0.1 to 0.8 &#x3bc;m, and this catalyst is characterized by further comprising an oxide of at least one metal selected from the group consisting of manganese, cobalt, nickel, zinc, zirconium, niobium, molybdenum, tin, tantalum, lanthanum and cerium as another catalytic component. The process for removing organohalogen compounds involves the use of this catalyst.

Catalyst and process for removing organohalogen compounds

The present invention provides a process for the purification of exhaust gases which process enables to effectively inhibit the discharge of the dioxins by low-cost modification of already existing incineration facilities which are formed from an incinerator and an electric dust collector or cyclone. Incinerator exhaust gases a dedusted with an electric dust collector or cyclone, and then treated with a ceramic filter to sufficiently remove dust from the exhaust gases and brought into contact with a catalyst to decompose and thereby remove the dioxins which are contained in the exhaust gases.

Process for the purification of exhaust gases

This invention discloses an adsorbent ideal or the removal of nitrogen oxides (NO.sub.x : nitrogen monoxide and nitrogen dioxide), particularly nitrogen dioxide, from an exhaust gas containing the nitrogen oxides at low concentrations and a method for efficient removal of nitrogen oxides, particularly nitrogen dioxide, from an exhaust gas containing the nitrogen oxides at low concentrations by the use of the adsorbent. The adsorbent either comprises at least one noble metal selected from the group consisting of Pt, Au, Ru, Rh, and Pd and/or a compound thereof supported on a carrier or comprises the noble metal component and an oxide of at least one heavy metal selected from the group consisting of Mn, Fe, Co, Ni, Cu, Zn and Pb, which may be supported on the carrier, if necessary.

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Himeji, Japan

Shinyuki Masaki