KR20200097401A - Metal Ion Extraction Device of Lubricant for Wet Wire Drawing - Google Patents

Abstract

The present invention relates to a device for extracting metal ions from waste lubricant for wet drawing. A device for extracting metal ions from waste lubricant for wet wire drawing according to the present invention is installed while being connected to a circulation tank of lubricant which is circulated and supplied for wet drawing. The lubricant circulation tank and a connecting unit are connected to a lubricant suction unit and a lubricant discharge unit of an electrolyzer, and the lubricant flows into and out of the electrolyzer. In addition, a bubble device includes a cathode plate and an anode plate formed of insoluble electrode electrolytic copper plates consisting of a cathode and an anode and titanium metal electrodes coated with a catalyst of 20% iridium oxide (IrO_2), 7% titanium dioxide (TiO_2), and 3% vanadium pentoxide (V_2O_5) or less. The bubble device generates a bubble state of lubricant as a means for increasing the adhesion rate of metal ion particles in the electrolyzer on the electrode. The device includes a rectifier for applying a DC current and a variable pulse current to the electrodes.

Description

Metal Ion Extraction Device of Lubricant for Wet Wire Drawing {Metal Ion Extraction Device of Lubricant for Wet Wire Drawing}

The present invention relates to a method for removing metal ion impurities contained in wet waste lubricating oil that is circulated for cooling and lubrication during drawing processing of a steel wire, and to a waste lubricating oil regeneration apparatus, and in more detail, a wet drawing process of a wire Wire wet drawing that improves the workability by improving the wet drawability of the wire while increasing the regeneration rate of the waste wet lubricant by removing impurity metal particles (Fe, Cu, Zn) accumulated in the wet lubricant used for It relates to a waste lubricant regeneration device for use.

In general, when drawing a wire in which the metal is rapidly deformed, a lot of heat is generated while maintaining a harsh condition of compression and friction at the contact surface between the wire and the drawing die, and scratches on the surface of the wire relatively soft compared to the die. Surface defects such as back occur.

In other words, the contact surface between the wire surface and the die surface is in a severe friction state.In order to reduce the friction force generated at this time, lubricant is supplied to the surface interface between the wire and the die, and friction between the wire and the die surface by the supplied lubricant The condition is divided into two types: fluid lubrication and boundary lubrication.

Fluid lubrication is a state in which the surface of the wire and the die are in indirect contact through a layer of lubricant, and becomes an ideal friction state, but the friction state between the wire and the die surface is broken by the high pressure applied to the two contact surfaces. It is a boundary lubrication state where fluid lubrication and non-lubrication are mixed.

Therefore, when drawing in the boundary lubrication state, pickup due to the breakage of the boundary lubricating film caused by rapid pressure rise and frictional heat, i.e., prevents the surface defect of the wire, reduces the friction coefficient and heat between the drawing die and the wire contact surface, and draws at the same time. In order to improve performance, the lubricant supplied to the contact surface between the wire and the drawing die differs in a lubricant supply method according to the characteristics of the wire to be drawn, and is largely classified into dry drawing and wet drawing according to the lubricant supply method.

Dry drawing is a wire in which lubricant is applied to the surface by dropping lubricant on the surface of the wire at a point on the wire travel path to the drawing die or by dipping the wire through the lubricant before passing the wire through the drawing die. The lubricant applied to the wire surface by wire drawing is not recovered.

Wet drawing is a drawing method applied to fine wire drawing with a wire diameter of 0.5 mm or less, which cannot apply an appropriate amount of lubricant to the wire surface by applying a lubricant to the dry drawing method and generates relatively high frictional heat. All of them are immersed in a lubricant coolant, which is an aqueous solution in which a wet lubricant is added to water at a certain concentration, and drawing is performed. Therefore, the wet lubricant must have cooling and cleaning properties in addition to lubricity in an aqueous solution state. In other words, wet lubricants have lower lubricity than dry lubricants, but have excellent cooling performance, and various animal and vegetable oils, mineral oils, synthetic oils and oil enhancers are the main components, and these components are uniformly dispersed and emulsified in water to use as a surfactant. Is added.

In general, for wet wire drawing, the raw wire rod is subjected to a pretreatment process such as surface scale removal and heat treatment, and then the surface is coated with a brass plated layer to prevent rust and improved wire drawing, and the wire rod coated with the plated layer is A plated wire is obtained by performing stepwise drawing in a wet drawing machine until a predetermined diameter is reached. At this time, in the drawing process of the brass plating wire, a multi-stage drawing capstan and a plurality of drawing dies are installed in the chamber filled with cooling lubricant to guide the drawing capstan and move the material wire passing through the drawing die step by step diameter reduction and It is carried out through a wet drawing machine that allows an increase in length to occur.

There are a mechanical method and a chemical method for removing the wire oxide layer generated from the steel wire drawing of a steel wire. Among them, the mechanical removal method is preferred in terms of the quality and performance of the wire after drawing the steel wire, but at the same time, the use of lubricant is inevitably increased. Therefore, it can be said that the recycling of lubricants has great economic value in terms of resource recycling.

Therefore, considering the global economic recession, mechanical overuse is a heavy burden, so the use of regenerated lubricant by a steel wire drawing lubricant regenerator is a great economic benefit in order to reduce initial cost and expenditure costs.

In the conventional wire wet drawing lubricant regeneration method, as the operating time of the drawing machine elapses, the cooling lubricant flowing inside the circulation system accumulates metal ions such as copper and zinc separated from the surface of the plating wire. As a result, the cooling lubricant is discarded when the concentration of the metal ions reaches a certain limit value after use for a certain period of time.

Therefore, in order to reduce the waste treatment cost by improving the wet drawing and the surface quality of the drawn wire and extending the service life of the cooling lubricant, metal ions contained in the cooling lubricant must be continuously removed during the wet drawing operation.

However, in the case of a general wet drawing machine, the metal ions accumulated in the cooling lubricant are trapped in the sludge generated in the cooling lubricant and are only naturally removed together with the sludge, and there is an appropriate method to otherwise remove the metal ions accumulated in the cooling lubricant. none.

Accordingly, the present invention is to extend the life of the cooling lubricant used in the conventional wet drawer and to improve the freshness of the wire, a device that can easily and efficiently remove metal ions accumulated in the cooling lubricant through an electrochemical method. There is a purpose to provide.

In order to achieve the above and other objects of the present invention, according to an embodiment of the present invention, it is achieved by a rectifier for direct current conversion and negative and positive electrodes intersected at regular intervals in a cooling lubricant circulation tank.

The electrode constituting the device for removing metal ions containing a cooling lubricant for wet drawing of the wire of the present invention may be a metal as a conductor, but it is preferable to use a copper plate with good current efficiency for the positive electrode, and metal ions dispersed in the cooling lubricant are electrodeposited. In the case of the negative electrode, it is necessary to use a metal that is electrically stable and not corroded by a cooling lubricant, and that the electrodeposited metal ions can be easily separated.

In addition, the electrode spacing and current density of the negative and positive electrodes commonly used in devices using electrolysis or reverse reaction of electrolysis are very important factors, and in the case of the present invention, the electrode gap between the negative and positive electrodes is There is a technical feature in that it is 5~15mm and the current density is 4~10A/dm2.

In addition, the number and size of electrodes installed in the cooling lubricant circulation tank are determined within a range capable of satisfying the current density, but the number of electrodes is preferably at least four or more for each of two negative and positive electrodes. This is because when the metal ion extraction apparatus of the present invention is configured in a single electrode method of one negative and one positive electrode, the cooling lubricant cannot be uniformly contacted with the electrode. The reasons for limiting the electrode spacing and current density as described above are as follows. If the electrode spacing is less than 5mm, short circuit due to electrodeposited metal ions can easily occur, and if it exceeds 15mm, the current efficiency sharply decreases, and the amount of metal ions deposited is significantly reduced. And, if the current density is less than 4A/dm2, the electrodeposition speed of metal ions becomes too slow, and if it exceeds 10A/dm2, the increase in the electrodeposition speed of metal ions sharply decreases compared to the increased current density. That is, the current efficiency decreases.

During wet drawing, copper and zinc in the brass plating layer on the surface of the steel wire are dissolved in the lubricant. The concentration of metal ions gradually increases with the use period of the lubricant, and the concentration of metal ions contained in the lubricant affects the freshness and workability. Currently, the concentration of these ions is controlled by supplying and disposing of a certain amount of lubricating liquid, and if the concentration of metal components such as copper and zinc is excessively increased after a considerable period of time and the freshness and workability are significantly reduced, all lubricants are discarded and new lubricants Supply and use. However, the method currently being used has problems of not only environmental problems in disposing of the lubricant after use, but also treatment costs and cost loss due to the continued purchase of new lubricants.

According to the present invention having the above-described configuration, the metal ion extraction apparatus of the present invention effectively removes metal ions accumulated in the cooling lubricant for wet drawing, thereby significantly increasing the life of the cooling lubricant, thereby reducing the wet lubricant and discarding the cooling lubricant. There is an effect of reducing the cost.

In addition, by removing metal ions that accumulate in the cooling lubricant, it has the advantage of improving the wire drawing productivity by improving the wire drawing productivity, and reducing the wire surface defects such as pickups that occur during the drawing process by suppressing the rate of decrease in the lubricity of the cooling lubricant. .

In addition, in the wet extraction metal ion extraction apparatus of the present invention, when connected with a dry waste lubricant regenerator at a cost of 50 liters per hour, more than 90% of contaminants can be removed.

1 is an apparatus for extracting metal ions from lubricating oil for wet drawing according to an embodiment of the present invention
2 is a copper plate of the anode electrode plate of the electrolyzer
3 is a titanium plate of a cathode electrode plate of an electrolytic cell
Figure 4 is a copper ion extraction concentration change amount treated for 5 hours
5 is a change amount of zinc ion extraction concentration treated for 5 hours

Hereinafter, an apparatus 10 for extracting metal ions from wet waste lubricant according to a preferred embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

1 is an apparatus for extracting lubricating oil metal ions for wet extraction according to an embodiment of the present invention, FIG. 2 is a copper plate 21 of a positive electrode plate of the electrolyzer shown in FIG. 1, and FIG. 3 is a titanium plate of a negative electrode plate ( 22).

In the present invention, it is characterized in that the wet drawn lubricant is regenerated by attaching copper ions and zinc ions in the lubricating oil to the negative plate by electrolysis through the metal ion extraction device 10 composed of the insoluble positive plate 21 and the negative plate 22. In the present invention, the wet lubricant refers to a lubricant commonly used for wet drawing of a wire, and is generally used, which is composed of fatty acids, oil improvers, pressure agents, surfactants, rubber adhesion promoters and defoaming agents, but is not limited thereto. .

The metal ion extraction device 10 is composed of an insoluble positive electrode plate 21, a negative electrode plate 22, a power supply rectifying device 32, and a bubble device 31. When a wet lubricant is placed in the extraction device and a current flows for a certain period of time, Copper ions and zinc ions dissolved in the lubricating oil are extracted to the negative plate by electrolytic reaction, so that the concentration of copper ions and zinc ions in the lubricating oil decreases. In this case, the amount of reduction in the concentration of metal ions may vary depending on various conditions, such as the energization time, current density, and variable pulse device.

That is, it refers to a waste lubricating oil metal ion extraction apparatus 10 for wet drawing of a wire, which is composed of a rectifier for applying a DC current and a variable pulse current to the electrodes.

In addition, a bubble device is provided through an insoluble electrode electrolysis copper plate 21 composed of a cathode and an anode, and a titanium metal plate 22 coated with a catalyst material and an inflow means in the electrolyzer, so that the metal ion particles of the electrolyzer adhere to the electrode. You can create a bubble state that increases

In addition, in the metal ion extraction device, the material of the insoluble negative electrode plate 22 contains 20% of iridium oxide (IrO2) and titanium dioxide (TiO2) among the constituents of the entire covering material on the titanium (Ti) metal plate electrode plate 22, which has very strong corrosion resistance. ) It is most preferable to use a material coated with 7%, vanadium pentoxide (V2O5) 3% or less, and the material of the positive electrode is preferably a copper plate.

Titanium (Ti) plate is used as the insoluble negative electrode plate, and iridium oxide (IrO2) is 20%, titanium dioxide (TiO2) 7%, vanadium pentoxide (V2O5) 3% or less among the constituents of the entire covering material of the plate. It is preferable to use a coating material.

It is preferable to set the current density in the metal ion extraction device in the range of 4 to 8 A/dm 2. If the current density is less than 4A/dm2, the removal rate of metal ions in the wet lubricating solution is too low, which is not preferable. If the current density exceeds 8A/dm2, the removal rate of metal ions in the wet lubricating liquid may increase, but since high voltage and high current are applied. There is a potential for safety hazards and a rapid increase in pH in wet lubricants.

An example of such a metal ion extraction device is shown in FIG. 1. 2 and 3 show the structures of the anode and cathode attached to the metal ion extraction device. However, the metal ion extraction apparatus that can be used in the present invention is not limited thereto.

Hereinafter, the present invention will be described in detail with reference to examples, but the following examples are for illustrative purposes only, and are not intended to limit the present invention.

(Example 1)

Using a titanium plate 22 coated with 20% iridium oxide (IrO2), 7% titanium dioxide (TiO2), and 3% vanadium pentoxide (V2O5) or less as a cathode, and a copper plate 21 as an anode, The metal ion extraction apparatus 10 having the same structure as 1a was manufactured in a standard of 350?200?25mm3. Using this, a wet lubricant (Supersol ADM: brand name) with a copper ion concentration of 2,000 to 2,100 ppm and a zinc ion concentration of 1,300 to 1400 ppm was treated at a current density of 4.0 A/dm 2 for 5 hours, and then a certain amount of lubricant was collected. As a result, the concentration of copper (Cu) ions and zinc (Zn) ions and other physical properties were examined and shown in Table 1.

(Example 2)

It was carried out in the same manner as in Example 1 except that the wet lubricating oil was treated at a current density of 5.0 A/dm 2 for 5 hours.

(Example 3)

It was carried out in the same manner as in Example 1, except that the wet lubricating oil was treated at a current density of 6.0 A/dm 2 for 5 hours.

(Example 4)

It was carried out in the same manner as in Example 1 except that the wet lubricating oil was treated at a current density of 7.0 A/dm 2 for 5 hours.

(Example 5)

It was carried out in the same manner as in Example 1 except that the wet lubricating oil was treated at a current density of 8.0 A/dm 2 for 5 hours.

[Method of property evaluation]

(1) Concentration of copper ions and zinc ions: It was measured using an ion coupling plasma spectroscopy (ICP, Ion Coupling Plasma).

(2) pH: It was measured using a pH meter.

10: metal ion extraction device 11: electrolyzer
12a: negative electrode plate connecting means 12b: positive electrode plate connecting means
21: Cu electrode plate 22: Ti electrode plate
23: pole plate support 31: bubble generating device
32: variable pulse rectifier 41: lubricant suction means
42: recycled lubricant discharge means

Claims (4)

It is installed in connection with a lubricating oil circulation tank that is circulated and supplied for wet drawing, and lubricating oil is introduced and discharged into the electrolyzer through the lubricating oil suction means and discharge means.
Titanium metal electrodes coated with an insoluble electrode electrolysis copper plate consisting of a cathode and an anode and a catalyst material,
A bubble device is provided through the inlet means in the electrolyzer to create a bubble state in which the metal ion particles in the electrolyzer increase the adhesion rate on the electrode.
Waste lubricating oil metal ion extraction device for wet drawing of a wire, characterized in that consisting of a rectifier for applying a DC current and a variable pulse current to the electrodes. In the regeneration method of waste lubricating oil for wet drawing using the extraction device according to claim 1,
Titanium (Ti) plate is used as the insoluble negative electrode plate, and iridium oxide (IrO2) is 20%, titanium dioxide (TiO2) 7%, vanadium pentoxide (V2O5) 3% or less among the constituents of the entire covering material of the plate. A method for regenerating waste lubricant for wet drawing, characterized in that a coating material is used and a copper plate material is used as the positive electrode plate. The method of claim 2, wherein the current density in the metal ion extraction device is in the range of 4 to 8 A/dm 2. The method of claim 2 or 3, wherein the rectifier comprises a variable pulse rectifier for increasing the degree of decomposition of metal ion particles on the inner and outer surfaces of the electrode.

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