JPS58145648A - Coal-burning cement raw material calcining process - 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 coal-fired cement raw material calcination method, and in particular, by using cement clinker firing equipment in which the main fuel of the calciner is coal, a part of the cement raw material is mixed with botanicals or oil shale. The present invention relates to a method for calcining raw materials in a method for manufacturing cement clinker using raw materials containing combustible components such as.

As shown in FIG. 1, this type of conventional cement clinker firing equipment includes a pulverizing IWS for pulverizing a normal cement raw material 1 and a cement raw material 2 containing combustibles, a suspension preheater 4, and a calcining burner 5. It consists of a calcining furnace 6, a rotary kiln 7, a clinker cooler 8, and a crushing device 10 for crushing coal 9 and supplying it to the calcining burner 5.

That is, regarding the cement raw material 2 containing BJ fuel in the conventional method, the cement raw material 2 containing combustible content is added to the usual crushing charge 6 for raw materials and pulverized, and the raw material powder is placed in the upper stage of the suspension preheater 4. was supplying. Therefore, by the time the calcining furnace reaches 6Vc, the raw material temperature is 70Vc.
Since the temperature exceeds 0°C, some of the combustibles will burn. Although this heat of combustion contributes to raising the temperature of the raw material, it is not useful for the decarboxylation reaction of CaCO3. As a result, the temperature of the exhaust gas from the suspension brake heater 4 rises by 2.5 cm. and,
Since the VC in the dust of the preheater 4 also contains unburned matter, it ultimately contributes only about 50% of the supplied combustible matter.

The present invention utilizes solid combustible materials such as botanicals and oil shale, which are difficult to utilize as they are, as part of the raw material for jukumento, and also provides a coal-fired material that can effectively utilize the calorific value of the combustible content. The object of the present invention is to provide a method for calcining cement l-coolant.

For this reason, the present invention is characterized in that when calcining cement raw materials using coal as the main fuel, cement raw materials containing combustibles are mixed in during the coal pulverization process, and this is used as a fuel for calcining.

An embodiment of the present invention will now be explained with reference to FIG.

A normal cement raw material 11, that is, a mixed powder of mainly calcareous raw materials and clay raw materials, is supplied from the 1st-stage supply port of the suspension breheater 4, descends while exchanging heat with the hot gas, and enters the calcining furnace 6. enter.

On the other hand, coal 9, which is the main fuel for the calciner 6, is supplied to a crusher 10 by a foot feeder 12 and turned into powder. At that time, cement raw material containing solid minerals such as bota and oil shale was used for $12
The powder is completely supplied to the same crushing device 10 by another bulk feeder 16 and becomes powder. Powder particle size is 88μ sieve and residue 4
Finish at around 15φ.

Then, the mixed powder of both is supplied to the calcination burner 5 installed in the calcination furnace 6 by the transportation device 14, and the calcination fI
6, the combustible components of the coal and raw materials are combusted and contribute to the calcination reaction of the cement raw materials. At the same time, the cement raw material containing combustible content is mixed with the cement raw material supplied to the suspension breheater 4 and fired in the subsequent rotary kiln to become cement clinker.
The amount of fuel t possessed by the raw materials is burned exclusively in the calciner 6,
Even if it remains in the furnace, it will be burned in the lower stage of the suspension preheater following the calcination furnace 6, so the total amount of heat left by the combustion will be effectively utilized. Furthermore, the exhaust gas dust from the suspension preheater 4 does not contain any unburned matter. Moreover, cement raw materials containing 1"-fuel are usually C
Since it contains acos and is mixed into the coal crushing device 10, it is expected that it will have a secondary effect that will help prevent coal dust explosions in subsequent devices such as the powdered coal transportation device 14. C Kill.

That is, the reaction when CaCO3 is decarboxylated is partly an endothermic reaction, and the combustion of carbon is prevented, so the above-mentioned secondary effects can be expected.

In this way, the present invention does not supply the cement raw material, which is rich in combustible content, to the suspension preheater together with ordinary raw materials, but instead uses the same crusher as the coal that is the main raw material of the calciner to process the coal with high combustible content. Are the cement raw materials containing them mixed and pulverized, and their transportation equipment and calcining burners also used for coal? Since this is a method in which the powder is shared and supplied to a calcining furnace and the heat of the combustible content is used as heat for firing the cement raw material, 100% of the combustible content of the raw material can be effectively used.
This is an energy-saving measure in the cement manufacturing field, and without major modification of existing equipment, it is sufficient to simply add a quantitative feeder for cement raw materials containing combustibles in front of the coal crushing equipment. As a side effect, it will also help prevent coal dust explosions.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional method, and FIG. 2 is an explanatory diagram of an embodiment of the present invention. 2... Cement raw material containing combustible matter, 4... Suspension preheater, 5... Calciner, 6... Calciner, 9... Stone, 10... Grinding device, 11... ...Ordinary cement raw materials, 1213...Quantitative feeder, 140
0. @Feeding device. Patent applicant: Ishikawajima Banreki Heavy Industries Co., Ltd. Agent
Patent Attorney Tomi Hisashi Koyama

Claims (1)

[Claims] 1. In a method of manufacturing cement clinker using raw materials containing combustibles as a part of the cement raw materials using cement clinker firing equipment that uses coal as the main fuel in a calcining furnace, the raw materials containing combustibles are replaced with the coal. The powder is mixed with the coal and pulverized in the same pulverizer as the pulverizer, and the transportation device and calcining burner are also used for coal, and the powder is supplied to the calciner, and the calorific value of the combustible content is transferred to the cement raw material. A coal-fired cement raw material calcination method characterized by utilizing the heat of calcination.