Mitsubishi Materials Corporation

Junzhu Wang

Hirokazu Shima

Yoshinori Takayama

Daisuke Sakaniwa

Eiichi Motohashi

Takuya Komatsu

Naohiro Higuchi

A fluidized calciner is provided which allows a reduction in the rate of unburned fuel at an outlet of a fluidized calciner to enable sufficient calcination while preventing possible occlusion in a preheater, even when pulverized coal of coal or coke, which has low combustion quality, is used as fuel, based on calculations in accordance with computational fluid dynamics based on the shape of an actual furnace and operational conditions. The present invention provides a fluidized calciner including a tubular furnace body () in which an axial direction is an up-down direction, a pulverized coal blowing line () through which fuel is blown into the furnace body (), a raw material chute () through which a cement raw material is loaded into the furnace body (), at least one air introduction pipe () through which introduced air is sucked, the pulverized coal blowing line (), the raw material chute (), and the air introduction pipe () being connected to a side portion of the furnace body (), and a fluidizing air blowing port () disposed at a bottom portion of the furnace body () and through which fluidizing air is blown into the furnace body (), in which a blowing port of the pulverized coal blowing line () is disposed below a suction port of the air introduction pipe () and above the fluidizing air blowing port ().

Fluidized calciner

The present invention provides a fluidized calciner which can perform sufficient calcination by reducing a rate of unburned fuel at an outlet of the fluidized calciner while preventing occlusion in a preheater. In the present invention, plural pulverized coal blowing lines (), raw material chute () of cement raw material, and first to fourth air introduction pipes (to) are connected to a bottom side wall of a tubular furnace body () whose upper end portion is closed by a top plate (); a fluidizing air blowing port () adapted to blow in fluidizing air is disposed at a bottom of the furnace body (); an exhaust gas duct () is connected to a top side wall of the furnace body located above the first and/or second air introduction pipes () by being spaced away from the top plate (); and blowing ports () of the pulverized coal blowing lines are disposed below suction ports of respective air introduction pipes (to) but above the fluidizing air blowing port (), and at least one of the blowing ports () is placed below the third or fourth air introduction pipe (or).

There is provided a cement plant including a chlorine bypass apparatus capable of efficiently reducing the chlorine concentration in a cement kiln due to exhaust gas extraction by a small amount, by preventing calciner exhaust gas low in chlorine concentration from contamination and extracting a part of kiln exhaust gas high in chlorine concentration. In the invention, a baffle wallwhich protrudes, on a lower faceof an exhaust ductof a calciner connected to the pipe inclination partof an exhaust gas piperising from a kiln inlet partof a cement kiln, toward a pipe inclination partside at an inclination angle &#x3b1; within a range of 20 to 60&#xb0; relative to the horizontal plane, and a spacing between a lower end edgeof the baffle wall and an opposite wall planeof the pipe inclination part is configured such that an average flow rate of the exhaust gas between the both falls within a range of 15 to 35 m/s.

Cement plant

A chlorine bypass device which can cool exhaust gas quickly by mixing extracted exhaust gas with cooling air at high efficiency, to thereby produce fine chloride dust, and increase dust recovery efficiency.

Chlorine bypass device

Providing a cement production apparatus in which raw material is supplied into a duct with being dispersed uniformly so that heat-exchanging efficiency is improved by even preheating and clogging and the like are prevented, so that stable operation can be carried out. Between cyclones at an upper stage and a cyclone at a lower stage disposed below cyclones at an upper stage, a ductis provided to introduce exhaust gas to the cyclones at the upper stage with distributing after flowing upward from the cyclone at the lower stage; at a lower position than a distribution partof the duct, a material-supplying pipeis connected for supplying cement raw material; at a connected part of the material-supplying pipeto the duct, a material-guiding chuteon which the cement raw material is supplied from the material-supplying pipeand which drops it into the ductis provided with protruding into the duct; and the material-guiding chuteis formed to have a flat upper surface and to be expandable by sliding so that insertion depth of a tip endfrom an inner-wall surfaceof the ductis 0.15 to 0.5 times of an inner diameter of the duct

Cement production apparatus

A cement production apparatus having: a ductin which exhaust gas drained from a lower cyclone flows upward, distributes and introduces the exhaust gas to upper cyclones; material-supplying pipesfor supplying cement raw material connected to both side parts of one side surface of the ductbelow a distribution partamong the upper cyclones; and a supply-amount controllerprovided on an upstream position above the material-supplying pipesfor controlling supply-amounts of the cement raw material to the material-supplying pipes: and when H is a vertical distance between a horizontal surface Ppassing through centers of distribution outletsof the upper cyclones and a horizontal surface Ppassing through centers of connecting portsof the material-supplying pipes, and D is a diameter of the duct, a ratio H/D is set to 1.4 to 2.5.

To provide a cement production apparatus in which heat-exchanging efficiency can be improved by even pre-heating by supplying material equally to cyclones above a duct and which can perform an operation with low pressure loss and small energy consumption. A cement production apparatus includes: a ductprovided between upper cyclonesA and a lower cycloneB being provided below the upper cyclonesA, the ductin which the exhaust gas drained from the lower cycloneB flows upward, distributing and introducing the exhaust gas to the upper cyclonesA; a plurality of material-supplying pipesfor supplying cement raw material provided on the ductbelow a distribution partto the plurality of the upper cyclonesA with a same number of distribution outletsamong the upper cyclonesA; and connection portsof the material-supplying pipesto the ducteach provided at each of positions corresponding to swirl flows of the exhaust gas poured into the distribution outlets

To provide a method and facility for enabling COgas generated in a cement manufacturing facility to be separated and recovered at a high concentration. To this end, according to the present invention, the calcination of a cement material and the recovery of COgas generated in a calciner are performed by one of the following steps of: [1] superheating the cement material before calcination to at least the calcination temperature thereof in a superheating furnace and then mixing the superheated cement material with a new cement material before calcination in a mixer/calciner; [2] mixing, in the mixer/calciner, the cement material before calcination with a part of high-temperature cement clinker discharged from a cement kiln; and [3] using an externally heated calciner.

[object Object]

An object of the present invention is to separate COgas generated in a cement-manufacturing facility in a high concentration and recover the COgas. The present invention includes: feeding a cement material before calcination and a heat medium which has a particle diameter larger than that of the cement material and has been heated to the calcination temperature or higher in a medium-heating furnace (), to a mixing calciner (); and recovering the COgas generated by the calcination of the cement material. The heat medium circulates between the medium-heating furnace and the mixing calciner. Another aspect of the present invention includes: feeding a cement material before calcination to a regenerative calciner () which has been heated to the calcination temperature or higher and has stored heat therein; and recovering the COgas generated by the calcination of the cement material.

Growing community of inventors

Naka, Japan

Junzhu Wang