JPH0768529B2 - Method for producing high-concentration coal / water slurry - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is to pulverize raw coal with a wet coarse pulverizer to produce a high-concentration coal / water slurry. The present invention relates to a method for producing a high-concentration coal / water slurry by finely pulverizing a coal / water slurry with a wet mill.

[Conventional technology]

Conventionally, as shown in FIG. 2, only a raw material consisting of raw coal, water, and an additive is supplied to a wet coarse crusher (4), and a high crushing process is performed by the coarse crushing process in the wet coarse crusher (4). The concentrated coal / water slurry is temporarily stored in the tank (9) through the pipe line (8) and, if necessary, supplied to the wet mill (5) for fine pulverization treatment, and this wet mill The high-concentration coal / water slurry finely pulverized in (5) is sent to the screen (6) for separating coarse coal particles, and the high-concentration coal / water slurry obtained by separating coarse coal particles in the screen (6) is manufactured. Was sent to the storage tank (7) as
See JP-A-61-283363).

[Problems to be solved by the invention]

However, the high-concentration coal slurry produced by the coarse crushing process in the wet coarse crusher (4) has a coarse average particle size of the coal, so that the coal tends to settle, and the width of the particle size distribution of the coal is narrow, so that the fluidity is low. Therefore, there is a problem that the pipeline (8) and the tank (9) are likely to be blocked between the wet coarse pulverizer (4) and the wet mill (5) and the transport power is increased. there were.

An object of the present invention is to reform highly concentrated coal / water slurry sent from a wet coarse pulverizer to a wet mill into a highly fluid one which is difficult to settle and has a high fluidity by an extremely simple and economical means.

[Means for solving problems]

The characteristic configuration of the method for producing a high-concentration coal / water slurry according to the present invention is that raw coal is coarsely pulverized by a wet coarse pulverizer to produce a high-concentration coal / water slurry, and the high-concentration coal produced by this wet coarse pulverizer is used. In the basic configuration of finely pulverizing the coal / water slurry by the wet mill, the high-concentration coal / water slurry finely pulverized by the wet mill is used in an amount of 5% by weight or more of the raw material supply amount to the wet coarse pulverizer. It is mixed in the feed material to the wet coarse pulverizer in a ratio, or is charged into the wet coarse pulverizer or mixed in the high-concentration coal / water slurry produced by the wet coarse pulverizer.

[Work]

That is, as a result of various experiments, the high-concentration coal / water slurry after being finely pulverized by the wet mill was used at a ratio of 5% by weight or more of the amount of the raw material supplied to the wet coarse pulverizer, and preferably 50%.
In a proportion of less than or equal to wt%, mixed in the feed material to the wet coarse crusher, or charged into the wet coarse crusher, or mixed in the high-concentration coal-water slurry produced by the wet coarse crusher,
It was confirmed that the settling property of the high-concentration coal / water slurry sent from the wet coarse crusher to the wet mill can be effectively reduced and the fluidity can be effectively improved.

〔The invention's effect〕

According to the present invention, it is possible to effectively reduce the sedimentation property of the high-concentration coal / water slurry sent from the wet coarse pulverizer to the wet mill and to effectively enhance the fluidity, and therefore, the wet coarse pulverizer and the wet coarse pulverizer are used. It is possible to avoid troubles on the transport surface and storage surface such as blockages in the pipelines and tanks with the mill, improve the productivity of high-concentration coal / water slurry, and reduce the required transport power to reduce production costs. It has become possible to reduce the above.

Moreover, since this is a simple improvement method in which a part of the high-concentration coal / water slurry after finely pulverized by a wet-type wet mill is returned to the upstream side, the burden on the facility cost is small and advantageous.

〔Example〕

 Next, an embodiment will be described with reference to FIG.

The raw material coal supplied from the hopper (1), the water supplied from the first tank (2), and the additive supplied from the second tank (3) were supplied to the wet coarse crusher (4) at an appropriate mixing ratio. Then, these raw materials are roughly pulverized by a wet coarse pulverizer (4) to produce a high-concentration coal / water slurry.

Raw coal generally has a particle size of 50 to 60 mm or less, and the mixing ratio of coal and water is generally about 60 to 75% in terms of coal weight concentration. Further, as the additive, for example, naphthalene sulfonate formalin condensate, polystyrene sulfonate, lignin sulfonate, polycarboxylate 0.3 ~
Use at 1.0% (vs coal) or polystyrene oxide at 0.5-1.5% (vs coal).

The high-concentration coal / water slurry produced by the coarse pulverization process in the wet coarse pulverizer (4) is supplied to the wet mill (5) to be finely pulverized, and the high-concentration coal finely pulverized in the wet mill (5). Most of the concentrated coal / water slurry is sent to the screen (6) to separate the coarse particles of coal, and the high quality concentrated coal / water slurry that passed through the screen (6) is stored in the storage tank (7). On the other hand, the coarse coal particles separated and collected by the screen (6) are returned to the wet mill (5) and finely pulverized again.

A part of the high-concentration coal / water slurry finely pulverized by the wet mill (5) accounts for 5% by weight or more of the amount of the raw material supplied to the wet coarse pulverizer (4), and preferably the production efficiency. From the aspect of improvement, at a rate of 50% or less, it is returned to the upstream side and charged into the wet coarse crusher (4), whereby the high-concentration coal / water slurry sent from the wet coarse crusher (4) to the wet mill (5). It reduces the sedimentation property and enhances the fluidity to facilitate the slurry transportation.

[Another embodiment]

In the above-described embodiment, the high-concentration coal / water slurry that has been finely pulverized by the wet mill (5) is wet coarsely pulverized at a rate of 5% by weight or more of the amount of the raw material supplied to the wet coarse pulverizer (4). Although it was introduced into the machine (4), similarly, for the purpose of improving the transportability, the high-concentration coal / water slurry after finely pulverized by the wet mill (5) was wet coarse pulverizer (4). 5% by weight or more of the amount of raw material supplied to the wet coarse pulverizer (4), or a high concentration coal / water slurry produced by the wet coarse pulverizer (4) The form may be adopted.

The specific configuration of the wet coarse pulverizer (4) can be appropriately selected, for example, a rod mill, and the specific configuration of the wet mill (5) can be appropriately selected, for example, one in which one stage or a plurality of stages are used for fine pulverization by a tower mill.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow sheet showing an embodiment of the present invention, and FIG. 2 is a flow sheet showing a conventional example. (4) …… Wet coarse crusher, (5) …… Wet mill.

Claims (2)

[Claims] 1. A high-concentration coal / water slurry is produced by roughly pulverizing raw material coal with a wet coarse pulverizer (4), and the high-concentration coal / water slurry produced by this wet coarse pulverizer (4) is wet. A method for producing a high-concentration coal / water slurry finely pulverized by a mill (5), wherein the high-concentration coal / water slurry finely pulverized by the wet mill (5) is treated by the wet coarse crusher (4). )
5% by weight or more of the amount of raw material supplied to the wet coarse crusher (4), or mixed into the raw material supplied to the wet coarse crusher (4), or the wet coarse crusher ( A method for producing a high-concentration coal / water slurry mixed with the high-concentration coal / water slurry produced in 4). 2. The high-concentration coal / water slurry after being finely pulverized by the wet mill (5) at a ratio of 50% by weight or less of the amount of raw material supplied to the wet coarse pulverizer (4), Claims to be mixed in the feed material to the coarse crusher (4), or charged in the wet coarse crusher (4), or mixed in the high-concentration coal / water slurry produced by the wet coarse crusher (4) The method for producing a high-concentration coal / water slurry according to item 1 of the above.