JPS607846Y2 - Coolant scum oil circulation recovery device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a coolant scum oil circulation and recovery device that recovers and regenerates the oil in the scum removed from the coolant and makes it possible to use the recycled oil again in the coolant.

Generally, a circulating oil supply system is adopted in rolling equipment.

In this method, when the coolant passes through rolling equipment, it is necessary to control the ash and iron content mixed in the emulsion to below a certain value. Suspended fine powder scale (scum) generated in the coolant tank is discharged from the system using a discharge device using a vacuum cleaner or skimming.

FIG. 1 shows a typical example of a conventional circulating oil supply system applied to a five-stand tandem mill.

As shown in this figure, the tandem mill has first stands 11 to fifth stands 15 along the flow direction of the steel plate 10.
are arranged in order.

Coolant is supplied to the second stand 12 to the fifth stand 15 in this tandem mill from a branch pipe 17 of a coolant pipe 16 via a header and a nozzle.

Once the coolant is supplied to each stand 12 to 15,
It is collected at each socket 18 provided at the bottom of the table, and is stored in a coolant tank 20 via a collection pipe 19.

This coolant tank 20 has the coolant pipe 16
are connected, coolant pump 21, strainer 22
Coolant is again supplied to each of the stands 12 to 15 via the cooler 23.

In this way - in the runt circulation path, the collection pipe 1
When the coolant from 9 is stored in the coolant tank 20, scum containing ash and iron is generated in the coolant tank 20.

This scum adversely affects rolling, so it is removed using a magnetic drum 24.

That is, the magnetic drum 24 is arranged at the upper part of the coolant tank 20 and is rotated with a part immersed in the surface layer of the coolant inside the tank 20 to discharge the scum to a discharge passage 25 provided outside the tank 20. be.

In this manner, in the circulating oil supply device, scum generated in the coolant is removed from the system during the circulation path.

Note that hot water is supplied from a hot water tank 26 through a hot water pipe 27 to the first stand 11 located on the most upstream side of the tandem mill, thereby improving the biting property of the steel plate 10.

By the way, in the above-mentioned conventional circulating oil supply system (Fig. 1), the change in iron and ash content in the coolant when the scum in the coolant tank 20 is removed using the magnetic drum 24 is shown in Fig. 2. show.

This means that the capacity of the coolant tank 20 is 60,000/
As shown in this figure, the ash concentration (curve A) and the iron concentration (curve B) decreased with time, and the scum discharge rate by the magnetic drum 24 decreased. It is understood that the effect of external discharge is large.

Here, the scum discharged shows the analysis results as shown in Table 1.

As shown in this table, the scum contains several percent of ash and iron, as well as several tens of percent of oil.

Therefore, as the scum is discharged, the oil content is also discharged, and as time passes, the oil concentration also bottoms out, as shown by curve C in FIG.

For this reason, according to the conventional method, not only the suspended solids in the emulsion but also the rolling oil are discharged out of the system at the same time, and if the amount of scum discharged increases, the oil concentration in the coolant will drop to the bottom. There is a problem that this causes an increase in the consumption of rolling oil.

For this reason, conventionally, in conjunction with the problem of waste oil disposal that accompanies discharge outside the system, standards have been set for the content of ash and iron contained in coolant emulsions, and the amount of scum that falls within the standards has been There was the complication of having to discharge the coolant to the outside and balance the properties of the coolant with the unit consumption of rolling oil.

The present invention focuses on the above-mentioned conventional problems, utilizes the coolant cleaning effect of scum discharged outside the system, and actively discharges scum outside the circulation system to purify the coolant. An object of the present invention is to provide a coolant scum oil circulation recovery device that prevents an increase in the unit consumption of rolling oil by regenerating rolling oil from scum and returning it to a coolant tank as recycled rolling oil.

In order to achieve the above object, the coolant scum oil circulation recovery device according to the present invention includes a scum recovery tank that collects the scum discharged from the coolant scum, heats and stirs the scum, and a scum recovery tank that is connected to the scum recovery tank. a primary treatment separator that separates oil from the scum; a primary treatment oil recovery tank that collects the separated oil and supplies hot water for stirring; and a primary treatment oil recovery tank that is connected to the primary treatment oil recovery tank. It consists of a secondary treatment separator that separates oil from oil again, and a recycled oil tank that recovers the recycled oil obtained from the secondary treatment separator and is capable of feeding the recycled oil to the coolant tank. , it became possible to recycle and recover oil from the scum that could be used as rolling oil.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 shows a schematic overall configuration diagram of the coolant scum oil circulation recovery device according to this embodiment.

As shown in this figure, the oil circulation recovery device is connected to a circulation oil supply device that circulates and supplies coolant to the rolling mill 30.

A coolant tank 31 constituting this circulating oil supply system includes a recovery tank 32 for storing recovered coolant, and a recovery tank 32 that stores recovered coolant.
The clean coolant tank 33 stores the coolant from which scum has been removed.

A coolant pipe 34 that supplies coolant from the coolant tank 31 to the rolling mill 30 is a clean coolant tank 3.
A recovery pipe 36 is connected to the recovery tank 32 and returns the coolant recovered at a socket 35 provided at the lower part of the table of the rolling mill 30 to the coolant tank 31 .

In the coolant tank of such a circulating oil supply system, a scum removing means (not shown) such as a magnetic drum for removing scum 37 from the recovered coolant is provided on the recovery tank 32 side.

A scum discharge path 38 is formed in the recovery tank 32 provided with such a removal means, and a scum recovery tank 39 is installed on the outlet side of the discharge path 38.

The scum collection tank 39 is for storing the discharged scum 37, and the scum collection tank 39 is equipped with a heating means 40 for heating the scum 37, and a heating means 40 for uniformly stirring the scum 37. A stirrer 41 is provided.

The heating temperature by the heating means 40 is 80 to 100°C.

The scum 37 heated and stirred in the scum collection tank 39 is supplied to a centrifugal separator 44 for primary treatment through a discharge pipe 42 provided in the tank 39 and a pump 43 interposed in the discharge pipe 42. Ru.

The primary treatment centrifuge 44 performs a primary treatment of separating the introduced scum 37 into three layers: oil, moisture, and other sludge.

The oil separated in this separator 44 is the primary treated oil 45
The oil is sent to the primary treatment recovery tank 47 via the oil supply pipe 46 and stored there.

On the other hand, the separated water 48 is stored in a water recovery tank 50 via a separate pipe 49, and the sludge 51 is discharged from the separator 44 to the outside of the system.

Primary treatment oil 45 separated by primary treatment centrifuge 44
is heated and stirred in the primary treated oil recovery tank 47 in the same way as the scum 37 in the scum recovery tank 39.

For this purpose, the tank 47 is equipped with a heating means 52 and a stirrer 53.

Further, a hot water pipe 55 from a hot water tank 54 is introduced into this tank 47 in order to mix hot water into the primary treated oil 45.

In the primary treatment recovery tank 47, hot water of 50% or less of the oil amount is added from the hot water tank 54, and the mixed treated oil is heated to 80 to 100% by using the heating means 52 and the stirrer 53.
The mixture is heated to 0°C and stirred.

The primary treated oil 45 mixed with warm water and heated and stirred in the primary treated oil recovery tank 47 is supplied to the secondary treatment centrifugal separator 58 by a pump 57 via a discharge pipe 56 provided in the tank 47. be done.

This centrifugal separator 58 for secondary treatment separates the primary treatment oil 45 into oil, moisture, and sludge in the same way as the separator 44 for primary treatment.

The oil separated by the secondary processing centrifuge 58 is recycled oil 5
9 is recovered into a recycled oil tank 61 via an oil feed pipe 60.

On the other hand, the water separated by the secondary treatment separator 58 is stored in the water recovery tank 50 via the piping 62, similarly to the moisture 48 separated by the primary treatment separator 44.

Furthermore, the sludge 63 is separately discharged outside the system.

The water recovery tank 50 that stores the water 48 separated by the primary and secondary separators 44 and 58 is provided with a water discharge pipe 64, and this pipe 64 is connected to a pump 65. is interposed.

Piping 64 is introduced into the coolant tank 31 so that the separated water can be reused.

The recycled oil recovery tank 61 includes a heating means 66 for heating and stirring the recycled oil 59, and a stirrer 67 in the tank 40.47.
It is set up in the same way.

On the other hand, in order to use this recycled oil 59 as rolling oil,
The recycled oil recovery tank 61 is provided with a return pipe 68 and a pump 69 is interposed therein, and the end of the return pipe 68 is introduced into the clean coolant tank 33 in order to return the recycled oil 59 to the coolant tank 31 by the pump 69. has been done.

The coolant scum oil circulation device configured in this manner collects the scum 37 generated in the coolant tank 31, heats and stirs the scum 37, and then uses the primary processing centrifuge 44 to separate oil, water, and sludge. Perform layer separation.

Warm water is added to this separated oil in a primary treatment oil recovery tank 47 in an amount of 50% or less of the oil, and after further heating and stirring, the liquid is passed through the centrifuge 58 again to separate the oil, and then rolled. It regenerates oil that can be used as oil.

According to such an oil circulation recovery device, the scum is passed through the centrifuge twice, and the second time, hot water is added to 50% of the oil amount.
It was decided to add the following range, and as a result, the moisture content was 1.
It is possible to regenerate rolling oil with an iron core content of 0.25% or less.

The following table shows the general properties of this recycled oil in comparison with coolant and new oil.

As shown in this table, the recycled oil has properties equivalent to those of a coolant emulsion and can be fully used as rolling oil.

In particular, according to this embodiment, the amount discharged outside the system as oil is reduced by 44.5 centrifuges for primary and secondary treatment.
Only a small amount of oil adheres to the sludge51゜63 discharged from B, and more than 90% of the oil contained in the scum can be returned to the coolant system as effective oil, so the amount of waste oil processed is also at the bottom. .

In addition, although the above-mentioned example explained the case where it is used for rolling equipment, it can also be used for other equipment that employs an equivalent runt.

As explained above, according to the present invention, it is possible to dramatically reduce the amount of ash and iron in the coolant without increasing the consumption of rolling oil. , which has a great effect on roll consumption.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing a conventional circulating lubrication system, Fig. 2 is a diagram showing changes in concentration of ash, iron, and oil in the coolant in a conventional circulating lubrication system, and Fig. 3 is a diagram of coolant scum according to this embodiment. FIG. 2 is a schematic configuration diagram of an oil circulation recovery device. 30...Rolling mill, 31---Coolant tank, 39...Scum collection tank, 44...
... Centrifugal separator for primary treatment, 47... Primary treatment oil recovery tank, 5... Centrifugal separator for secondary treatment 61 ... Recycled oil recovery Tank, 68...
...Return piping.

Claims (1)

[Scope of utility model registration request] A scum collection tank that collects scum discharged from a coolant tank installed in a coolant circulation route to rolling equipment, etc., heats and stirs the scum, and a scum collection tank installed in a discharge route of this scum collection tank that separates oil from the scum. A primary treatment separator, a primary treatment oil recovery tank that collects the oil obtained from the primary treatment separator and supplies hot water to the oil to heat and agitate it, and a discharge route for this primary treatment oil recovery tank. a secondary treatment separator installed in the secondary treatment separator to separate oil from the primary treatment oil; and a recycled oil recovery tank capable of recovering the recycled oil obtained from the secondary treatment separator and sending the recycled oil to the coolant tank. A coolant scum oil circulation recovery device consisting of.