JPH07116960A - Processing method for grinding oil mixture containing sludge, its processing facility and sludge briquette - Google Patents

Abstract

PURPOSE:To collect sludge as a briquette being easy in handling by filtering a grinding oil mixture containing sludge to obtain a sludge mixture containing a small quantity of the grinding oil, and compressing the sludge mixture to collect the sludge substantially containing no grinding oil as a briquette. CONSTITUTION:A sludge mixture is filtered through a horizontal belt type filter 11 and a centrifugal separation type filter 12 and a pure grinding oil is therefore collected. Next the sludge mixture is carried to a pressing machine 17 by a conveyor 16 and compressed for further collecting the grinding oil, and collected as a briquette 19 substantially containing no grinding oil. The briquette 19 formed of the sludge solidified by compression does not substantially contain the grinding oil, and is reused in an electric furnace for producing stainless steel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a grinding oil mixture containing sludge generated in a metal strip grinding line for polishing and removing flaws on the surface of a metal strip, a treatment facility for performing the treatment, and Relates to a briquette for reusing sludge generated in the above grinding line.

[0002]

2. Description of the Related Art In a manufacturing process of hot-rolled steel strip and cold-rolled steel strip of stainless steel, a device for continuously grinding the surface of a steel strip to remove a flaw generated on the surface of the steel strip. (Steel strip grinding line) is known (JP-A-1
-228776 and Jitsukaihei 4-22109).

Usually, in a steel strip grinding line, an endless belt, which is made of cloth or paper as a base material and has abrasive grains baked on its surface with an adhesive, is used to grind the surface of the steel strip while spraying grinding oil as a coolant.

A grinding oil mixture containing polishing debris (sludge) is discharged from such a grinding line. In order to recycle the grinding oil in this mixture, the mixture is subjected to filtration to collect the grinding oil. This filtration is
Usually, a horizontal belt filter is used to recover most of the grinding oil, and then a sludge mixture containing 30 to 50% by weight of grinding oil is further filtered using a centrifugal filter. And recover a significant amount of grinding oil.

However, the sludge mixture produced by such a filtration operation is virgin and still contains more than 10% grinding oil. Therefore, from the viewpoint of resource saving, it is desired to recover the grinding oil contained in the sludge mixture and reuse the sludge.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to be able to recover grinding oil from a grinding oil mixture containing sludge generated in a steel strip grinding line at a high recovery rate and to effectively use the above sludge. What is possible is to provide a treatment method that can be recovered as a steelmaking material, for example. Another object of the present invention is to provide a processing facility that can be used in the above processing method. A further object of the present invention is to provide a briquette in which sludge generated in a steel strip grinding line can be used as a steelmaking material.

[0007]

According to the present invention, a first
In addition, the grinding oil mixture containing sludge generated in the metal band grinding line was filtered to obtain a sludge mixture containing a small amount of grinding oil, and the sludge mixture was squeezed to collect sludge substantially free of grinding oil as a briquette. And a method for treating a grinding oil mixture containing sludge generated in a metal band grinding line, characterized in that the grinding oil separated by the filtration and the pressing is recovered for reuse.

According to the present invention, secondly, a filtering device for filtering a grinding oil mixture containing sludge generated in a metal band grinding line, and a sludge mixture containing a small amount of grinding oil obtained by this filtering device are squeezed. For treating a grinding oil mixture containing sludge generated in a metal band grinding line, which is provided with a squeezing device for crushing, a filtering device, and a flow path for collecting grinding oil separated from the squeezing device. To be done.

Thirdly, according to the present invention, thirdly, the sludge generated in the metal band grinding line has a weight of 2 to 50 kg, and the grinding oil content is 5% by weight or less. A featured briquette is provided.

The above objects of the present invention are achieved by these inventions. BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below, with which other objects, configurations, advantages, and effects of the present invention will become apparent.

FIG. 1 is a typical schematic view of a grinding line for a metal strip such as a hot rolled steel strip or a cold rolled steel strip.
FIG. 2 is a schematic diagram showing one embodiment of the treatment method and treatment equipment of the present invention. Hereinafter, a case where the metal strip is a hot-rolled steel strip or a cold-rolled steel strip will be described with reference to FIG. 1 and FIG. 2. However, in the present invention, the metal strip is stainless steel, high Ni.
(36%, 42%) Steel, Ti steel, high carbon steel, etc. are also applied.

In the steel strip grinding line 4 shown in FIG.
Is ground by an endless belt grinder 2. At this time, grinding oil is sprayed from the header 3 toward the surface of the steel strip in order to cool and provide lubricity to improve grinding efficiency. The cotton-like polishing dust (sludge) generated by the grinding is transferred together with the grinding oil, and is sent to the horizontal belt type filter 11 as a grinding oil mixture through the flow path 21 in FIG.

This grinding oil mixture usually contains 50 sludges.
About 70 wt% is contained. The grinding oil is usually a paraffin oil, but 10% or less of water may be added for the purpose of preventing ignition.

In FIG. 2, the grinding oil mixture from the steel strip grinding line 4 is filtered by the horizontal belt type filter 11 through the flow path 21. The filter 14 as a filter medium used in the horizontal belt type filter 11 is held by a wire mesh as a base material and a cloth filter medium is mounted thereon. As the material of the cloth, for example, one made of polyamide fiber or polyester fiber is used. A mesh having a JIS mesh of 40 to 80 mesh is used. Known horizontal belt type filters are used in the market, and the above filters are marketed under the names such as so-called Hoffman filters.

The clean grinding oil recovered by this filtration is sent to the grinding oil recovery tank 13 via the flow path 22. The sludge on the filter 14 contains 30 to 50% by weight of grinding oil.
The sludge mixture contained therein is conveyed to the centrifugal filter 12 by the conveyor 15. The conveyed sludge mixture is further filtered by the centrifugal filter 12 to collect clean grinding oil. The grinding oil recovered here may be sent to the filter 14 of the horizontal belt type filter 11 for the purpose of filtering the contained fine sludge through the flow path 23, or to the grinding oil recovery tank 13 via the flow path 27. You may send it.

The centrifugal filter 12 is known per se, and for example, the one described in Japanese Utility Model Publication No. 64-4441 can be used.

The sludge mixture obtained in the centrifugal filter 12 usually contains about 10 to 20% by weight of grinding oil. Although it depends on the properties of the grinding oil and the properties of the sludge, it is industrially difficult to reduce the content of the grinding oil to 10% by weight or less using a centrifugal separator.

The sludge mixture is conveyed to the press 17 by the conveyor 16 and squeezed, and further, the grinding oil is collected and is collected as the briquette 19 substantially containing no grinding oil. Press machine 17 used for compression
As such, those known per se are used, for example, a cylinder type cylinder pressing machine, a square type pressing machine and the like are used.

The grinding oil recovered by pressing is sent to the grinding oil recovery tank via the flow path 26. On the other hand, the briquette produced by solidifying sludge by pressing does not substantially contain grinding oil, and the content of grinding oil is usually 5% by weight or less, preferably 3% by weight or less. With the grinding oil content of this level, even if the briquette is reused in an electric furnace for producing stainless steel, flames are hardly generated and the briquette can be suitably reused. Due to the performance of the press, it is industrially difficult to reduce the content of the grinding oil to 1% by weight or less.

The weight of each briquette is 2 to 50 k.
A value of g is preferable in terms of handling and press capacity. The shape of the briquette can be cylindrical, prismatic, or spherical.

The briquette 19 produced by the press machine 17 is conveyed by the conveyor 18 to receive the briquette receiving bag 1
It is stored at 9 and is then transported from time to time, for example to a steel mill for reuse.

Further, the grinding oil is supplied from the grinding oil tank 13 to the steel strip grinding line through the flow path 24. The grinding oil tank 13 is replenished with new grinding oil by the flow path 25.

The operations of filtration and squeezing and the recovery of grinding oil described above can be continuously and fully automated.

[0024]

According to the present invention, the grinding oil and the sludge can be efficiently recovered from the grinding oil mixture containing the sludge generated from the metal band grinding line. Particularly, the sludge is prepared as a briquette which is easy to handle. Can be used in a metal manufacturing plant?

[Brief description of drawings]

FIG. 1 is a schematic view showing a steel strip grinding line.

FIG. 2 is a schematic diagram showing a treatment process and equipment of the present invention.

[Explanation of symbols]

 1 Metal Band 2 Beldo Grinder 3 Grinding Oil Spray Header 4 Steel Band Grinding Line 11 Horizontal Belt Filter 12 Centrifugal Filter 13 Grinding Oil Recovery Tank 14 Filter 15 Conveyor 16 Conveyor 17 Press Machine 18 Conveyor 19 Briquette 20 Briquette Back 21 flow channel 22 flow channel 23 flow channel 24 flow channel 25 flow channel 26 flow channel 27 flow channel

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B01D 36/02 7305-4D

Claims (7)

[Claims] 1. A sludge mixture containing sludge generated in a metal strip grinding line is filtered to obtain a sludge mixture containing a small amount of grinding oil, and the sludge mixture is squeezed to obtain a sludge substantially free of grinding oil. And a method for treating a grinding oil mixture containing sludge generated in a metal band grinding line, wherein the grinding oil separated by the filtration and the pressing is recovered for reuse. 2. The processing method according to claim 1, wherein the filtration is performed using a horizontal belt type filter and a centrifugal type filter in this order. 3. The processing method according to claim 1, wherein the briquette has a grinding oil content of 5% by weight or less. 4. A filtering device for filtering a grinding oil mixture containing sludge generated in a metal band grinding line, a pressing device for pressing a sludge mixture containing a small amount of grinding oil obtained by the filtering device, and the filtering device. A facility for treating a grinding oil mixture containing sludge generated in a metal strip grinding line, which is provided with a flow path for collecting the grinding oil separated from the pressing device. 5. The treatment facility according to claim 4, wherein the filtration device comprises a horizontal belt type filter and a centrifugal type filter located behind the horizontal belt type filter. 6. A briquette comprising sludge generated in a metal strip grinding line, having a weight of 2 to 50 kg per piece and containing a grinding oil content of 5% by weight or less. 7. The briquette is prepared by filtering a grinding oil mixture containing sludge generated in a metal band grinding line and squeezing the obtained sludge mixture containing a small amount of grinding oil. The stated briquette.