A method and system for producing nano-active powder materials. The method can be used with a reactor system comprising stages in which input particles flow under gravity progressively through stages of the reactor. A powder injector first stage in which ground input precursor powder is injected into the reactor. An externally heated preheater stage may be in the reactor, in which the precursor powder is heated to a temperature of calcination reaction. An externally heated calciner stage in the reactor, in which primary precursor volatile constituents can be rapidly removed calcination reactions as a high purity gas stream to produce the desired nano-active product. A post-processing reactor stage in which there is a change of the gas stream composition to produce the desired hot powder product by virtue of the nano-activity of the first powder material. A powder ejector stage in which the hot powder product is ejected from the reactor.

A method and system for producing nano-active powder materials. The method can be used with a reactor system comprising stages in which input particles flow under gravity progressively through stages of the reactor. A powder injector first stage in which ground input precursor powder is injected into the reactor. An externally heated preheater stage may be in the reactor, in which the precursor powder is heated to a temperature of calcination reaction. An externally heated calciner stage in the reactor, in which primary precursor volatile constituents can be rapidly removed calcination reactions as a high purity gas stream to produce the desired nano-active product. A post-processing reactor stage in which there is a change of the gas stream composition to produce the desired hot powder product by virtue of the nano-activity of the first powder material. A powder ejector stage in which the hot powder product is ejected from the reactor.

Disclosed are a method for separately preparing light magnesium oxide and calcium oxide by using dolomite and an application thereof in preparation of a calcium-magnesium composite expanding agent. In the method for preparing light magnesium oxide and calcium oxide, based on the difference in decomposition temperature between magnesium carbonate and calcium carbonate during the calcination and decomposition of dolomite and the difference in the weight of the materials after decomposition, the effective separation of magnesium oxide and calcium oxide is realized by a one-step method, thus separately preparing light magnesium oxide and light calcium oxide. The calcium-magnesium composite expanding agent is prepared by using the foregoing light magnesium oxide and calcium oxide. On the one hand, the present invention solves the problem of the limited origin of the light magnesium oxide raw material of the magnesium expanding component in the calcium-magnesium composite expanding agent.

The present invention relates to a process for conducting endothermic gas phase or gas-solid reactions, wherein the endothermic reaction is conducted in a production phase in a first reactor zone, the production zone, which is at least partly filled with solid particles, where the solid particles are in the form of a fixed bed, of a moving bed and in sections/or in the form of a fluidized bed, and the product-containing gas stream is drawn off from the production zone in the region of the highest temperature level plus/minus 200 K and the product-containing gas stream is guided through a second reactor zone, the heat recycling zone, which at least partly comprises a fixed bed, where the heat from the product-containing gas stream is stored in the fixed bed, and, in the subsequent purge step, a purge gas is guided through the production zone and the heat recycling zone in the same flow direction, and, in a heating zone disposed between the production zone and the heat recycling zone, the heat required for the endothermic reaction is introduced into the product-containing gas stream and into the purge stream or into the purge stream, and then, in a regeneration phase, a gas is passed through the two reactor zones in the reverse flow direction and the production zone is heated up; the present invention further relates to a structured reactor comprising three zones, a production zone containing solid particles, a heating zone and a heat recycling zone containing a fixed bed, wherein the solid particles and the fixed bed consist of different materials.

Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

A method for producing a dust-reducing and dust-absorbing material from a nonmetallic mineral and a raw material from a cement plant. The method includes calcining the limestone block, to obtain quicklime; cooling the quicklime at ambient temperature, drying and pulverizing the quicklime, to obtain a first powder essentially consisting of a quicklime powder and a calcium carbonate powder; fully drying and grinding a nonmetallic mineral, to obtain a nonmetallic mineral powder; mixing the first powder and the nonmetallic mineral powder, stirring to be uniform, to obtain a mixture, and ball milling the mixture, to obtain a nano-powder; adding a dust-absorbing material to the nano-powder, adding water and mixing, and pouring the resulting mixture into a mold, and stoving; and air drying the resulting mixture, to obtain a cavernous dust-reducing and dust-absorbing material.

A method for producing a dust-reducing and dust-absorbing material from a nonmetallic mineral and a raw material from a cement plant. The method includes calcining the limestone block, to obtain quicklime; cooling the quicklime at ambient temperature, drying and pulverizing the quicklime, to obtain a first powder essentially consisting of a quicklime powder and a calcium carbonate powder; fully drying and grinding a nonmetallic mineral, to obtain a nonmetallic mineral powder; mixing the first powder and the nonmetallic mineral powder, stirring to be uniform, to obtain a mixture, and ball milling the mixture, to obtain a nano-powder; adding a dust-absorbing material to the nano-powder, adding water and mixing, and pouring the resulting mixture into a mold, and stoving; and air drying the resulting mixture, to obtain a cavernous dust-reducing and dust-absorbing material.

This invention relates to manufacturing briquettes, pellets and shapes from recycled asphaltic limestone powder derived from waste residential roofing products. Briquettes and pellets are manufactured through a densification process at varying temperatures, creating recycled asphalt pellets, asphalt limestone pellets and bio mass and coal fines briquettes. Various shapes, including curbs and posts, are manufactured through heat and pressure in molds. Seawalls, walkways and wall panels are manufactured by blending asphaltic limestone powders with polymer resins and extruded or pultruded into shapes.

Method and installation for calcining cement raw meal in a calciner whereby fuel and a calciner oxidant having an oxygen content of at least 30% vol are introduced into the calciner so as to generate either an oxidant-lean zone or a fuel-lean zone in the calciner located between the lowermost fuel inlet level and the lowermost oxidant inlet level of the calciner, between 50% and 100% by weight of the raw meal being supplied to the calciner upstream of and/or within the oxidant-lean, respectively the fuel-lean zone.

Method and installation for calcining cement raw meal in a calciner whereby fuel and a calciner oxidant having an oxygen content of at least 30% vol are introduced into the calciner so as to generate either an oxidant-lean zone or a fuel-lean zone in the calciner located between the lowermost fuel inlet level and the lowermost oxidant inlet level of the calciner, between 50% and 100% by weight of the raw meal being supplied to the calciner upstream of and/or within the oxidant-lean, respectively the fuel-lean zone.