JPS5925611B2 - Method for clarifying slurry wastewater containing pulverized coal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for clarifying slurry wastewater containing pulverized coal.

Generally, slurry-like wastewater discharged from coal mines contains pulverized coal on the order of microns, and therefore, if this is discharged as is, it pollutes rivers and causes a so-called pollution problem.

In order to clarify slurry-like wastewater containing such pulverized coal, for example, a binder such as heavy oil is directly mixed into the wastewater to granulate the pulverized coal, and the granulated material is separated and removed by one filtration. However, since pulverized coal is very fine, it is difficult to attach a binder such as heavy oil to it, and therefore it is difficult to granulate pulverized coal and separate and remove it.

Furthermore, since pulverized coal has a large surface area per unit weight, it is necessary to add a large amount of binder, and after all, this method cannot efficiently clarify wastewater.

This invention has been made in view of the above points, and it is an object of the present invention to provide a method that can very quickly separate and remove pulverized coal from wastewater and clarify wastewater very efficiently.

This invention will be explained below based on the drawings.

In FIG. 1, slurry wastewater from a mine containing pulverized coal on the order of microns is introduced into three filter tanks 1 through supply pipes 2. In FIG.

These filter tanks 1 are arranged side by side within the same plane.

A packed bed 3 made of coarse coal to which a binder such as heavy oil is attached is provided in each ij overfilling tank 1.

Here, in order to make the packed bed 3, coarse granulated coal having a particle size of several meters and a binder such as heavy oil are mixed in advance.

Since coal and oil generally have an affinity for each other, a binder such as heavy oil adheres to the surface of the coarse coal, thereby forming the packed bed 3.

As the binder, heavy oil, dissolved oil, light oil, distillation residue oil, vegetable oil, etc. are used.

Then, the pulverized coal-containing wastewater introduced from the supply pipe 2 in each JJ filter tank 1 is passed through these packed beds 3.

Then, the pulverized coal in the wastewater is taken in by adhering to the binder on the surface of the coarse coal in the packed bed 3, thereby clarifying the wastewater.

The clear water thus obtained is taken out from the bottom of the filtration tank 1 through a discharge pipe 4.

Note that a screen or the like is provided at the discharge port to prevent the granulated material of pulverized coal containing coarse granulated coal from flowing out from the discharge pipe 4.

Moreover, if the capture efficiency of pulverized coal in the packed bed 3 decreases,
A binder such as heavy oil may be applied again to the surface of the coarse coal of the packed bed 3.

In this case, a method may be used in which, for example, a suspension of a binder such as heavy oil dispersed in water is poured over the packed bed 3 to newly adhere the binder to the surface of the coarse coal.

As the wastewater is clarified in this way, granules are formed in the packed bed 3, with coarse charcoal as the core and pulverized charcoal attached to the binder on its surface.

When this granulated material grows to a sufficient size, it is taken out from the filtration tank 1.

The granules thus obtained are composed of coarse granulated coal, a binder, and pulverized coal, and have a size suitable for subsequent removal of coal particles such as dehydration and drying. It is something that

FIG. 2 illustrates an apparatus for carrying out the method of the invention in multiple stages.

As shown in the figure, three filtration tanks 1 each having a packed bed 3 are arranged stepwise and in series so that their heights are different in order, and the discharge pipes 4 of the upper and middle filtration tanks 1 are arranged in series. They are shown above the next middle and lower sewage tanks 1, respectively.

Then, slurry-like wastewater containing pulverized coal is supplied from the supply pipe 2 at the top stage, and this wastewater is made to pass through the packed beds 3 of each filtration tank 1 in order from above to clarify the wastewater.

In this way, the wastewater can be repeatedly clarified, and in the end very clean clarified water containing almost no pulverized coal can be obtained.

The structure of the packed bed 3 of each filtration tank 1 is the same as in the embodiment shown in FIG. 1 above.

In each of the above embodiments, slurry-like wastewater containing pulverized coal is introduced above the packed bed 3 of each filtration tank 1,
Clear water is discharged from the bottom of the packed bed 3 after filtration, but
Conversely, the waste water containing pulverized coal may be introduced into the lower side of the packed bed 3 and the clear water may be taken out from the upper side of the packed bed 3, or the waste water containing pulverized coal may be introduced into the middle part of the packed bed 3. It is also possible.

In these cases, it is necessary to take appropriate measures to prevent the packed bed 3 from flowing out, such as providing a leakage prevention member such as a net on the upper surface thereof.

As described above, the method of the present invention includes providing a packed bed 3 made of coarse granulated coal with a binder attached to the surface in the filtration tank 1, and disposing slurry-like wastewater containing pulverized coal in the filtration tank 1. The pulverized coal contained in the wastewater is made to adhere to the binder on the surface of the coarse coal by introducing the wastewater and passing it through the packed bed 3, thereby separating the pulverized coal from the wastewater and clarifying the wastewater. Therefore, the pulverized coal in the waste water can be separated and removed very quickly, and the waste water can be clarified very efficiently.

[Brief explanation of drawings]

The drawings show an example of an apparatus for carrying out the method of the present invention, and FIG. 1 is a partially cutaway perspective view of the first embodiment, and FIG. 2 is a sectional view of the second embodiment. 1...Filter tank, 2...Drainage supply pipe containing pulverized coal, 3...Filled bed, 4...Clear water discharge pipe.

Claims (1)

[Claims] 1 In the filtration tank 1, a packed bed 3 made of coarse granulated coal with a binder attached to the surface is provided, and slurry-like wastewater containing pulverized coal is introduced into the filtration tank 1 and passed through the packed bed 3. A slurry containing pulverized coal is characterized in that the pulverized coal contained in the wastewater is attached to the binder on the surface of the coarse coal, thereby separating the pulverized coal from the wastewater and clarifying the wastewater. How to clarify wastewater.