JPH0346841Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention supplies coal/water slurry to the first end side of a vibrating sieve screen, and extracts coal coarse from the second end of the sieve screen. This invention relates to a coal/water slurry screen for separating and collecting particles.

[Conventional technology]

Conventionally, as shown in FIG. 3, the entire sieve screen 12 is formed into a flat surface with a gently sloped surface having an angle γ that increases from the first end 12a to the second end 12b.・Water slurry is supplied from the management 10 to the one end 12a side of the sieve screen 12, and the sieve screen 1
High quality, consisting of coal fine enough through 2.
In other words, the coal/water slurry with good combustion efficiency without clogging in the burner is collected into the slurry receiver 8, and the coarse coal particles are sent to the second end 12b by the vibration of the sieve screen 12 in the direction of arrow A. It was configured to separate and collect the waste into 11 parts.

[Problem that the invention attempts to solve]

However, in order to reduce the top size of coal fine particles in the high-concentration coal/water slurry as a product and improve quality, if the openings of the sieve screen 12 are made sufficiently small, the high-concentration coal - The water slurry flows down to the second end 12b due to the inertia flowing down from the pipe 10, and the fine coal particles are separated and collected in the collection container 11 along with the coarse coal particles, resulting in a low product recovery rate. . Incidentally, if the inclination angle γ of the sieve screen 12 is made too steep, the coarse coal particles cannot be fed, and therefore there is an upper limit to the inclination angle γ of the sieve screen 12, causing the above-mentioned troubles.

Therefore, in reality, the openings of the sieve screen 12 are widened to sufficiently increase the product recovery rate, and the quality of the highly concentrated coal/water slurry cannot be sufficiently improved.

The purpose of the present invention is to separate coarse particles using a sieve screen to sufficiently improve the product quality by making the openings of the sieve screen sufficiently small while increasing the product recovery rate sufficiently. .

[Means for solving problems]

A characteristic configuration of the present invention is that a steeply sloped portion is formed in the screen between the first end and the second end of the screen to be vibrated, and the slope is higher toward the second end, and the steeply sloped portion is In addition to setting the inclination angle β to 5 to 30 degrees and the height H to 5 to 15 mm, the sieve screen is higher toward the second end except for the steep slope part, so that the inclination angle α is 0<α<
The reason is that it is formed on a gently sloped surface of 8 degrees, and its effects are as follows.

[Effect]

In other words, as a result of various experiments, when a steeply sloped part with an inclination angle β of 5 degrees or more and a height H of 5 mm or more was formed on the sieve screen, coal/water slurry was supplied downstream to the first end of the sieve screen. Moreover, even if coarse particles are separated using a screen with small openings, which prevents blockage in the burner and obtains a sufficiently high-quality product in terms of combustion efficiency, the inertial flow of the coal/water slurry on the screen The action of the steep slope reliably prevents the trouble of fine coal particles reaching the second end of the sieve screen.
We were able to confirm that sufficient amounts of fine coal particles could be recovered from the screen, increasing the product recovery rate.

Furthermore, by setting the inclination angle β of the steeply sloped part to 30 degrees or less and the height H to 15mm or less, and setting the inclination angle α of the sieve screen other than the steeply sloped part to 0<α<8°, coal fine particles can be reduced. It was confirmed that the coarse coal particles could be smoothly and reliably fed to the second end regardless of the presence of a steeply sloped part for stopping, and that the coarse coal particles could be separated well.

[Effect of idea]

As a result, it has become possible to separate coarse coal particles while increasing the product recovery rate by using a sieve screen with sufficiently small openings, and to provide a high quality, highly concentrated coal/water slurry at a low cost.

〔Example〕

Next, examples will be shown with reference to drawings.

As shown in FIG. 1, appropriate amounts of raw material coal from the hopper 1, water from the first tank 2, and dispersant from the second tank 3 are supplied to a wet mill 4, and the wet mill produces highly concentrated coal and It is configured to create a water slurry.

The blending ratio of coal to water is generally 60 in terms of coal weight concentration.
~75%. In addition, as a dispersant, for example, naphthalene sulfonate formalin condensate,
Use polystyrene sulfonate, lignin sulfonate, polycarboxylate at 0.3 to 1.0% (based on coal), or use polystyrene oxide at 0.5 to 1.5%.
% (vs. coal).

The third tank 5 is filled with the highly concentrated coal/water slurry (coal concentration of about 60 to 75%) obtained by the wet mill 4.
An appropriate amount of anti-dehydration agent is added, coarse coal particles are separated from the highly concentrated coal/water slurry by a screen 6, and the high quality product that passes through the screen 6 is collected into a storage tank 7, and the separated coal The structure is such that the coarse particles are returned to the wet mill 4 and pulverized again.

At this time, the trouble that the highly concentrated coal/water slurry on the screen 6 is dehydrated and the coal particles do not pass through the screen 6 can be prevented by the action of the dehydration inhibitor, and the product recovery rate can be sufficiently increased.

As the dehydration inhibitor, suitable clay minerals, cellulose, gum substances, etc. can be used.

As shown in FIG. 2, on the screen 6,
A sieve screen 9 is attached to the slurry receiver 8 so as to be able to vibrate freely by a drive device as shown by arrow A, and a highly concentrated coal/water slurry from a pipe 10 is supplied flowing down to the first end 9a side of the sieve screen 9. The coarse coal particles on the sieve screen 9 are sent to the collection container 11 from the second end 9b by the vibration of the sieve screen 9.

Between the first end 9a and the second end 9b, a steeply sloped part 9c is formed in the sieve screen 9, the slope being higher toward the second end 9b, and the slope angle β of the steeply sloped part 9c is set to 5 to 15 degrees. The height H is set to 5 to 15 mm, and the sieve screen 9 is set at an angle of inclination α higher toward the second end 9b than at the steeply sloped portion 9c.
is formed on a gently sloped surface of 0<α<8°, and the inertial flow accompanying the flow down from the pipe 10 is stopped at the steeply sloped portion 9c, and the coarse coal particles can be smoothly sent to the second end portion 9b. It is structured as follows.

[Another example]

Next, another embodiment will be described.

The concentration of the coal/water slurry can be changed as appropriate.

The opening size of the sieve screen 9 is generally 0.2 to 1.5 mm.
It is.

The position of the steeply sloped portion 9c is desirably closer to the second end portion 9b, but can be appropriately selected, and a plurality of steeply sloped portions 9c may be provided.

The specific structure of the wet mill 4 can be appropriately selected, and for example, one that coarsely pulverizes with a rod mill and then finely pulverizes with a tower mill in one or more stages can be used.

Note that although reference numerals are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, in which FIG. 1 is a flow sheet and FIG. 2 is a conceptual diagram of a screen. FIG. 3 is a conceptual diagram of a conventional example. 9... Sieve screen, 9a... First end, 9b... Second end,
9c... Steep slope.

Claims (1)

[Scope of utility model registration request] Coal/water slurry is supplied to the first end 9a side of the sieve screen 9 to be vibrated, and the second end 9b of the sieve screen 9 is supplied.
A coal/water slurry screen for separating and recovering coarse coal particles from the coal/water slurry, the first end 9a
and the second end 9b.
A steeply sloped portion 9c that is higher toward the sides is formed on the sieve screen 9,
The steeply inclined portion 9c has an inclination angle β of 5 to 30 degrees and a height H of 5 to 15 mm, and the steeply inclined portion 9c
In this screen for coal/water slurry, the sieve screen 9 is formed into a gently sloped surface that is higher toward the second end 9b and has an inclination angle α of 0<α<8°.