JPS61127650A - Method and apparatus for cooling white cement clinker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for producing clinker for white cement, which white cement is substantially equivalent in chemical and physical properties to conventional Portland cement;
Portland cement (gray cement) by white color
It is a type of cement that can be distinguished from the clinker, and its production method involves spraying a reducing agent in the clinker just before the clinker leaves the rotary kiln, and injecting a coolant immediately after the clinker leaves the rotary kiln to quickly cool the clinker. is further cooled in the cooler.

A method of the above type is known from US Pat. No. 3,074,705. A reducing agent, e.g. oil, sprayed onto the clinker at the exit of the kiln reduces the clinker and prevents surface oxidation during initial cooling, and a coolant, preferably water, sprayed onto the clinker immediately thereafter is heated to about 500°C. The clinker is cooled to a temperature at which no oxidation of the clinker occurs and therefore no discoloration of the clinker occurs.

In order to reduce discoloration, the clinker must be sprayed with suitable water, which flows into the kiln plant and generates a large amount of steam without putting a load on the kiln plant, and which also soaks into the clinker and causes the clinker to It is a drawback of this known method that it does not have a negative effect on the quality of the cement produced from.

Furthermore, during subsequent drying and final cooling in a cooler where cooling is carried out by air, the clinker particles are reheated at the surface by the relatively large amount of residual heat still present within the clinker. It is clear that when exposed to air, it becomes oxidized again and therefore changes color when exposed directly to air, which has a negative effect on the whiteness of the treated cement.

In order to avoid such discoloration, especially of large linker particles, it is known to allow the entire amount of clinker to fall directly from the clinker outlet of the kiln into a water bath and to be cooled very quickly. However, such a method requires that the entire amount of clinker be completely dried, and this also has the above-mentioned negative effects on the quality of the finished cement due to the infiltration of the entire amount of clinker.

The aim of the invention is to reduce these disadvantages and, according to the invention, the clinker, after being sprayed with a reducing agent, is allowed to fall onto a collision device at the inlet of the cooler to partially crush the clinker and cool it down. The clinker is then sprayed with a
The clinker is finished cooled and dried by passing relatively slowly through a cooler in the cooling air into fine parts, and partially cooled by quickly passing through a cooler and finished cooled in a water bath. The coarse fraction is separated in a cooler and the coarse fraction is removed from the water bath, retaining sufficient residual heat for self-drying.

By this method, the heat from the fine parts of the clinker is used for complete drying of the fine parts in the cooler without discoloring the clinker, while the large talinker or coarse parts pass quickly through the cooler, so that the clinker The surface layer is only briefly exposed to the air in the cooler, thereby minimizing the risk of oxidation and discoloration again during cooling of the finish in the water bath.

The invention also includes an apparatus for carrying out the above method. This equipment includes a rotary kiln for baking and sintering cement clinker, a rotary cooler, a first spraying device for spraying a reducing agent onto the clinker at the clinker outlet of the kiln, and a first spraying device for spraying the refrigerant into the clinker at the clinker inlet. a second atomizing device for atomizing and an impingement plate device mounted below the clinker outlet of the kiln and in front of the cooler inlet, and a dam ring at the cooler inlet to separate the clinker into fine and coarse parts; a separating and conveying device in the cooler for separating the coarse portions into portions and quickly conveying the coarse portions through the cooler; and a water tank at the outlet of the cooler for cooling the coarse portions passed through the cooler by a conveyor. It is equipped with

The separating and conveying device may be constituted by a helical lifter or screw mounted inside the cooler and spaced at a predetermined distance from the shell of the cooler by a spacer element.

The separation/conveying device quickly transports clinker that is too large to pass through the gap between the periphery of the lifter and the inside of the cooler through the cooler and into the water tank, while clinker smaller than this gap is normally transported. It passes through a cooler in a relatively slow manner and is cooled by cooling air to a salinity such that no oxidation occurs again.

As explained, water is the preferred coolant used at the inlet of the cooler, and to remove the water vapor thus generated, the cooler may be provided with a suction tube in a known manner.

The inlet opening of the suction tube is oriented downwardly towards the talin force at the inlet of the cooler.

A device according to the invention will now be described with reference to the accompanying diagrammatic drawings, in which: FIG.

fi) [Example - @Explanation - The clinker outlet end 1 of a rotary kiln has a conventional burner 2 and is surrounded by an outlet housing 3, which has an inclined impingement plate device 4 at its bottom. have.

An underlying rotary cooler 5 for cooling the material processed in the kiln has a dam ring 6 at its inlet end and a spiral lid 7 along its entire length, the lifter 7 having a spacer It is mounted by means of an element 8 extending a distance from the inside of the cooler shell 5.

At the outlet end of the cooler there is a water tank 9 which is equipped with a conveyor 10 for discharging the coarse portion of the cooled clinker from the water tank and dropping it into a conhair 12''.

Furthermore, the cooler shell 5 has a gating device 1) at the outlet end of the cooler for dropping the cooled clinker fines directly onto the conveyor 12.
Transfers the total amount of cooled clinker.

The cooler 5 further comprises a tube 13 for supplying coolant to the inlet of the cooler and a suction tube 14 with an inlet opening 15 directed downwards for sucking out water vapor at the inlet of the cooler.

Clinker reducing agent is fed through tube 16 to the clinker outlet of the kiln.

The device operates in the following manner. 1) When the hot clinker with a temperature above 00°C leaves the kiln, spray reducing oil onto the clinker as shown at 17 without creating a fire.

The clinker falls from the kiln outlet into the stationary housing 3, hits the impact plate 4 and is partially crushed and guided towards the cooler inlet. At the inlet of the cooler, the clinker is cooled with water, as shown at 18.

The clinker passes through a dam ring 6, which homogenizes and controls the flow of the clinker passing through the water spray zone 18, and the clinker flows to a cooler 5 where it is finely divided by a separating and conveying device, namely a screw arrangement W7.8. It is separated into a part and a coarse part.

The fine parts pass between the screw device 7 and the inside of the cooler shell 5, are cooled to below 500° C. by cooler air, and fall directly onto the conveyor 12 through the gate 1).

Compatible parts whose particle size is larger than the gap determined by the spacer element 8 cannot pass through the gap between the peripheral part of the screw device 7 and the inside of the cooler shell 5 and therefore the screw device With a rough pinch of the l
ul! It is then cooled in a water tank to a temperature below 500°C.

Due to this rapid transport through the cooler 5, the surface of the large clinker particles is hardly oxidized again before cooling of the finish in the water bath 9. Even the finer parts of the clinker which pass through the cooler 5 more slowly are cooled so quickly that they do not oxidize again in the cooler 5.

The water vapor generated by the injection i18 is sucked out through the inlet port 15 of the suction pipe 14, and does not put any load on the kiln.

The fine parts that have passed through the cooler 5 are discharged through a gate device 1) at the end of the cooler and fall onto a conveyor 12. The coarse portion is removed from the water tank by the conveyor 10 at such a rate that the clinker still retains sufficient residual heat for self-drying and is discharged onto the conveyor 12.

[Brief explanation of drawings]

The figure is a longitudinal section through the end cooler of a rotary kiln plant. 1... Talinker exit end of rotary kiln 5... Cooler 6... Dam ring 7... Lifter 9... Water tank 12... Conveyor.

Claims (3)

[Claims] (1) A white method that involves spraying the clinker with a reducing agent as it exits the rotary kiln, then spraying a coolant onto the clinker to rapidly cool the clinker, and further cooling the clinker in its cooler. Regarding the production method of clinker for cement, after being sprayed with a reducing agent, the clinker is dropped onto a collision device at the inlet of the cooler to partially crush the clinker, and then sprayed with a cooling agent, and then the clinker is sprayed with cooling air. In fine parts the clinker is finish cooled and dried by passing relatively slowly through a cooler, and into coarse parts where it is partially cooled by quickly passing through a cooler and finish cooled in a water bath. A method for producing clinker for white cement, characterized in that the parts are separated in a cooler and the coarse parts are taken out of the water bath, retaining sufficient residual heat for self-drying. (2) A rotary kiln for baking and sintering cement clinker, a rotary cooler, a first spraying device for spraying a reducing agent onto the clinker at the clinker outlet of the kiln, and a first spraying device for spraying the refrigerant onto the clinker at the clinker inlet. a second atomizing device for spraying the clinker in the fine and coarse portions; and a collision plate device mounted below the kiln clinker outlet and in front of the cooler inlet; a separation/conveying device in the cooler for separating the coarse parts and quickly transporting the coarse parts through the cooler; and a water tank at the outlet of the cooler for cooling the coarse parts passed through the cooler by the conveyor. A manufacturing device for clinker for white cement, characterized by the following: (3) The separating and conveying device is characterized in that it is constituted by a helical lifter or screw installed inside the cooler and spaced apart from the shell of the cooler by a spacer element at a predetermined distance. Apparatus according to claim 2.