JPS6223412A - Method for removing clogging of filtering material for filter machine - Google Patents

Abstract

PURPOSE:To easily and effectively perform washing while enhancing the washing effect of a filter material, by washing the filter material with water with temp. of 30 deg.C or less. CONSTITUTION:A filter material clogged by a vinyl chloride power and polyvi nyl alcohol is washed with water of temp. of 30 deg.C or less. Whereupon, because polyvinyl alcohol is well dissolved, the vinyl chloride fine powder also becomes easy to separate and washing effect is enhanced. That is, vinyl chloride waste water containing the vinyl chloride fine powder and polyvinyl alcohol is sent to a raw liquid tank 4 by a vinyl chloride waste water line 3 to be stored therein and sent into a filter tank 1 through a raw liquid injection line 6 by a filter pump 5 and filtered. A valve 11 is closed (while a valve 14 is kept closed) and a valve 12 is opened in such a state that the filter tank 1 is opened to atmospheric pressure and water with temp. of 30 deg.C is allowed to enter the inside (filtrate discharge side) of a filter material 2 by a water supply line 13 to perform backwashing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for removing clogging of a filter medium for filtration (waste water etc. generated in a vinyl chloride manufacturing process).

[Prior Art] Wastewater generated in the vinyl chloride manufacturing process contains fine powder of vinyl chloride, polyvinyl alcohol, etc. Therefore, as shown in FIG. 60°C) is sent to the filtration tank 1 by the filter pump 5, and the tsukiyo (filtered by the filter pump 5) is discharged from the filtrate discharge line 8, and the vinyl chloride powder collected per person is collected. .

However, when the wastewater is filtered at a temperature of 40 to 60[deg.] C., polyvinyl alcohol and vinyl chloride powder gradually accumulate on the surface of the door material 2, which significantly reduces the amount of filtration.

Therefore, conventionally, in order to prevent clogging of the filter medium 2, a compressed air injection line 15 is connected to the filtrate discharge line 8, and compressed air is injected into the inside of the filter medium 2 from the injection line 15, and backwashing is performed in the waste liquid. At the same time, due to bubbling of waste liquid,
Filter medium 2 was being cleaned.

``Problems to be solved by the invention'' However, even with this backwashing using compressed air and bubbling of waste liquid, the cleaning effect is not sufficient and clogging occurs quickly, requiring frequent cleaning operations. there was.

Furthermore, if regeneration by cleaning is repeated, the cleaning effect will hardly improve, so it is necessary to disassemble the filter medium and clean it with a brush or the like, or to replace the filter medium with a new one.

[Means for Solving the Problem] The present inventor has determined that the cleaning effect is not sufficient in the range of 40 to 60°C due to the low solubility of polyvinyl alcohol.
The present invention was completed based on the discovery that when water at a temperature of 0° C. or lower is used, the solubility of polyvinyl alcohol increases and the cleaning effect is significantly improved.

That is, the present invention relates to a method for removing clogging of a moon phase (filtration mode) characterized by washing the moon phase with water of 30° C. or lower.

Cleaning action] When the moon phase (which is clogged with vinyl chloride powder and polyvinyl alcohol) is washed with water at 30°C or lower, the polyvinyl alcohol dissolves well, making it easier for the fine vinyl chloride powder to be removed, and the cleaning effect is significantly enhanced.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 shows an example of filtration equipment used in carrying out the present invention, in which 1 is a filtration tank, 2 is a moon phase, 3 is a vinyl chloride wastewater line, 4 is a raw solution tank for wastewater storage, and 5 is the filter pump, 6 is the stock solution injection line, and 7 is the overflow 1)
1 output line, 8 is a) Tsukiyo discharge line connected to the above-mentioned material 2, 9, 10.11 are valves provided in each of the above-mentioned lines 6.7.8, and valve 1 of the above-mentioned) Tsukiyo discharge line 8.
1 Upstream, a compressed air injection line 1 is connected with a water supply line 13 having a valve 12 and has a valve 14.
5 is connected, and a water supply line 17 having a valve 16 is connected to the downstream side of the valve 9 of the stock solution injection line 6, and a water discharge line 19 having a valve 18 is connected.

In the figure, 20 indicates a discharge valve provided at the bottom of the filter tank 1.

The method for removing clogging during moon phase 2 is as follows.

Vinyl chloride wastewater containing fine vinyl chloride powder and polyvinyl alcohol is sent to a stock solution tank 4 via a vinyl chloride wastewater line 3 and stored therein, and sent into the filtration tank 1 via a stock solution injection line 6 by a filter pump 5. ) Filter tank 1
Inside, the moonlit night filtered by the moon phase 2 is discharged from the moonlit discharge line 8, and fine vinyl chloride powder and polyvinyl alcohol accumulate outside the moon phase 2.

) After completion of filtration) The filter residue adhering to the surface of the moon phase 2 is discharged through the discharge valve 20.

) Close the door slag discharge valve 20, and open the valve 10゜18.
) to bring the inside of the filtration tank 1 to atmospheric pressure.

) Leave the filtration tank 1 open to atmospheric pressure, close the valve 11 (leave the valve 14 closed), open the valve 12, and
Water with a temperature below 'C is introduced into the inside of the moon phase 2 (on the moon night discharge side) via the water supply line 13 for backwashing.

Since the polyvinyl alcohol clogged in the moon phase 2 becomes easier to dissolve, the clogging condition of the fine vinyl chloride powder is alleviated, the fine vinyl chloride powder is easily detached, and the backwashing water can easily pass through.

Then, the valve 12 is closed to stop the water supply, and the valve 14 is opened to supply compressed air from the compressed air supply inlet 15).
Pour it inside the moon phase 2 to backwash. As a result, the vinyl chloride fine powder stuck in the moon phase 2 can be removed more effectively.

The above-described backwashing operation using water at 30° C. or lower and backwashing operation using compressed air are repeated several times, and the backwashing water during this time is discharged through the water discharge line 19 or the discharge valve 20.

) If the lunar phase 2 is clogged to a normal degree, the above backwashing operation is sufficient; however, if the lunar phase 2 is significantly clogged, the following operation is further performed.

The valve 18 and the discharge valve 20 of the water discharge line 19 are closed, the valve 12 is opened, and water at a temperature of 30°C or lower is flowed through the water supply line 13 in a backwashing state during the moon phase 2, and the inside of the filter tank 1 is filled with water. When water overflows from the overflow discharge line 7, the valve 12 is closed to stop the water supply. At this time, if a certain degree of backwashing effect has already been achieved with the water of moon phase 2 through the above-mentioned cleaning operation, some or all of the water below 30°C is injected into the water injection line 17 by turning on the valve 16). It may also be injected into the filtration tank 1.

Next, open the valve 14 and inject compressed air into the inside of the moon phase 2, and backwash it with compressed air in water below 30 degrees Celsius.
Bubble the outer surface of Moon Phase 2. Therefore, the cleaning effect is synergistically increased by the backwashing and bubbling effect using water at 30° C. or lower and compressed air.

When the above cleaning operation is completed, the valve 14 is closed, and then the valves 9 and 10 are opened to circulate the stock solution through the filter tank 1 through the filter pump 5 (from the stock solution tank 4 to the filter pump 5), and then) to start filtration.

It should be noted that the method for removing clogging of a filtration-like filter medium according to the present invention is not limited to the above-mentioned embodiments, and only backwashing with compressed air may be performed in water at 30° C. or lower. It goes without saying that various modifications may be made without departing from the gist of the present invention, such as the fact that only backwashing with water at temperatures below 0.degree. C. is sufficient.

[Effects of the Invention] As explained above, according to the method of removing clogging from a filtration mode filter medium of the present invention, various effects as described below are exhibited.

(Since the D i2 material is washed with water at 30° C. or lower, the polyvinyl alcohol can be well dissolved, so that the fine vinyl chloride powder is also easily removed, and the cleaning effect is significantly enhanced.

(II) Conventional cleaning methods were not very effective and required disassembling and cleaning or replacing the filter media, but this method is simple and can be carried out easily and effectively with only a small amount of additional equipment. .

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of filtration equipment used in carrying out the method of the present invention, and FIG. 2 is a diagram showing an example of conventional filtration equipment. 1) filtration tank, 2; 2 materials, 7 overflow discharge line, 8 1 liquid discharge line, 10, 11, 1.2゜1
4j6, 18 are valves, 13.17 is water supply line, 1
5 is a compressed air injection line, 19 is a water discharge line, and 20 is a discharge valve.

Claims (1)

[Claims] 1) A method for removing clogging of a filter medium for a filter, which comprises washing the filter medium with water at a temperature of 30° C. or lower.