JP2021041380A - Distillation separating device and method for tcb - Google Patents

Abstract

To provide a distillation separating device and a method for TCB that can reduce TCB included in PCB to the utmost, and can thereby reduce the amount of a catalyst used for dechlorination on PCB and lower the costs for harmless facilities.SOLUTION: A distillation separating device for TCB comprises: an oil removing cleaning part 2 which receives and cleans a processed product including PCB, TCB, cleaning oil, and water; a water separating tower 3 which distills and separates extracted oil and PCB-containing cleaning oil discharged from the oil removing cleaning part 2 into a distillate including water and bottoms including thick PCB, TCB and cleaning oil; and a cleaning oil recovery tower 4 which separates the bottoms including thick PCB, TCB and cleaning oil produced through the distillation in the water separating tower 3 into the distillate and the bottoms by distillation, wherein the distillate of the cleaning oil recovery tower 4 includes the cleaning oil, which is sent as recycled cleaning oil to the oil removing cleaning part 2; and the bottoms of the cleaning oil recovery tower 4 includes the thick PCB and TCB. The distillation separating device further comprises a TCB separating tower 9 which distills and separates the bottoms of the cleaning oil recovery tower 4 including the thick PCB and TCB into a distillate including TCB and bottoms including PCB.SELECTED DRAWING: Figure 1

Description

The present invention relates to a TCB distillation separation device and a method, and more particularly to a TCB distillation separation device and a method for separating and removing a TCB from a PCB containing a TCB generated by degreasing and cleaning a PCB-contaminated device.

PCB (polychlorinated biphenyl) has been widely used as an insulating oil for electrical equipment such as capacitors and transformers because of its excellent stability, nonflammability, and electrical insulation. Has become clear and new use is prohibited.

PCB-contaminated equipment such as capacitors and transformers that already contain PCB-containing insulating oil have been recovered and detoxified in special facilities.

Patent No. 536932 Patent No. 5639931

Patent Document 1 includes a cleaning unit for cleaning equipment containing PCB-containing insulating oil with cleaning oil, and a distillation regeneration unit for distilling PCB-containing cleaning oil generated by cleaning to produce regenerated cleaning oil. PCB-contaminated equipment that has a distillation tower for separating the PCB-containing cleaning oil into a distillate having a lower PCB concentration and a canned liquid having a higher PCB concentration than the PCB-containing cleaning oil is harmless. The method of dismantling the chemical equipment is disclosed.

Patent Document 2 discloses a method of efficiently detoxifying and disassembling the distillation column used in Patent Document 1.

However, in the detoxification facilities of Patent Documents 1 and 2, since TCB is not considered to be mixed in PCB, the method of removing TCB is not considered at all.

Since TCB is not toxic by itself, it is a conventional wisdom that it is not treated unless it is necessary to treat it, and it is not considered at all in Patent Documents 1 and 2.

The present inventor uses a palladium catalyst in his / her dechlorination process, but when TCB is mixed in PCB, there is a problem that palladium consumption is significantly increased due to the presence of the TCB. As a result, there was a serious problem that the processing plant itself became soaring.

Therefore, according to the present invention, since the TCB contained in the PCB can be removed to the utmost limit, the amount of catalyst used in the dechlorination treatment of the PCB can be reduced, and the cost of the detoxification equipment can be reduced. The challenge is to provide.

Other problems of the present invention will be clarified by the following description.

Hereinafter, the subject of the present invention will be solved by each of the following inventions.

(Claim 1)
An oil-draining cleaning unit that accepts and cleans processed products containing PCB, TCB, cleaning oil, and water.
A water separation tower that distills and separates the degreased oil discharged from the degreasing cleaning section and the PCB-containing cleaning oil into a distillate containing water and a can distillate containing concentrated PCB, TCB and cleaning oil.
It is provided with a cleaning oil recovery tower that separates canned liquor containing concentrated PCB, TCB and cleaning oil generated by distillation of the water separation tower into distillate and canned liquor by distillation.
The distillate of the cleaning oil recovery tower contains cleaning oil, and the cleaning oil is sent to the oil removal cleaning unit as regenerated cleaning oil, and the canned liquid of the cleaning oil recovery tower contains concentrated PCB and TCB.
Discharged from a processed product comprising a TCB separation tower that distills and separates the canned liquid of the cleaning oil recovery tower containing concentrated PCB and TCB into a distillate containing TCB and a canned liquid containing PCB. Distillation separation device for TCB contained in PCB-containing cleaning oil.
(Claim 2)
Processed products containing PCB, TCB, cleaning oil and water are accepted into the degreasing cleaning unit for cleaning.
Next, the degreased oil discharged from the degreasing cleaning section and the PCB-containing cleaning oil are received in a water separation tower, and distilled and separated into a distillate containing water and a can distillate containing concentrated PCB, TCB and cleaning oil.
Next, the canned liquid containing concentrated PCB, TCB and cleaning oil generated by the distillation of the water separation tower is received in the cleaning oil recovery tower, separated into the distillate and the canned liquid by distillation, and the cleaning oil is recovered. The distillate of the column contains cleaning oil, and the cleaning oil is sent to the oil removal cleaning unit as regenerated cleaning oil, and the canned solution of the cleaning oil recovery tower contains concentrated PCB and TCB.
Next, the processed product is characterized in that the canned liquid of the cleaning oil recovery tower containing concentrated PCB and TCB is received in the TCB separation tower and distilled and separated into a distillate containing TCB and a canned liquid containing PCB. A method for distilling and separating TCB contained in PCB-containing cleaning oil discharged from.

According to the present invention, since TCB contained in PCB can be removed to the utmost limit, the amount of catalyst used in the dechlorination treatment of PCB can be reduced, and the cost of detoxification equipment can be reduced. A distillation separation device and method for TCB contained in a PCB-containing cleaning oil can be provided.

A processing flow chart showing an example of an apparatus for carrying out the distillation separation method of TCB according to the present invention. Processing flow diagram of conventional equipment

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a processing flow chart showing an example of an apparatus for carrying out the distillation separation method of TCB.

In FIG. 1, reference numeral 1 denotes a processed product, which is sent to the oil removal cleaning unit 2.

The device constituting the oil removal cleaning unit 2 has two functions of an oil removal device and a rough cleaning device. The degreasing device may be one device or a plurality of devices as long as it can accept the object to be processed.

Examples of the processed object 1 include transformers and capacitors that are aged and may leak PCBs, large transformers and capacitors that do not leak, and small transformers and capacitors. When draining oil, for example, the internal PCB or TCB-containing insulating oil is drained from a hole made in a casing such as a transformer. The oil removal device preferably includes a large oil removal chamber, a leaked product oil removal chamber, and a small oil removal chamber.
After draining the oil from the processed product, it is washed with a washing device. Specifically, the inside of the transformer or capacitor is cleaned with cleaning oil.

The cleaning oil is preferably a TCB-like substance, and examples thereof include hydrocarbon-based high-performance cleaning agents, such as HC-250 (manufactured by Tosoh Corporation) and NS Clean 220 (manufactured by JXTG Energy Co., Ltd.). In addition to this, HC-250 equivalent products and NS Clean 220 equivalent products may be used, as long as they have a boiling point lower than that of TCB and can peel off PCB adhering to the inside of the processed product 1 when cleaning the processed product 1. Good.

The oil-draining cleaning unit 2 disassembles the internally cleaned transformer by a rough disassembling device (not shown) on the casing and internal equipment.
After the oil is drained and washed by the oil draining cleaning unit 2, it is branched into a plurality of parts (not shown).
In the present embodiment, the processed product 1 is received by the oil-draining cleaning unit 2 for cleaning, and PCB-containing cleaning oil containing PCB, TCB, cleaning oil and water is generated.

The degreased oil discharged from the degreasing cleaning unit 2 and the PCB-containing cleaning oil are received in the water separation tower 3 and distilled and separated to obtain a distillate and a can distillate. The canned liquid contains concentrated PCB, TCB and cleaning oil. The distillate contains water.

The canned liquid is sent to the cleaning oil recovery tower 4 and separated into a canned liquid containing concentrated PCB and TCB and a distillate containing cleaning oil. For example, since the bp (boiling point) of PCB is 360 to 390 ° C, the bp of TCB is 210 ° C, and the bp of cleaning oil (HC-250) is 170 ° C, the separation temperature of the cleaning oil recovery tower 4 is set to 180 ° C. Then, the cleaning oil is separated into the distillate, and the concentrated PCB and TCB are separated into the canned liquid.

The distillate from the cleaning oil recovery tower 4 is sent to the cleaning oil recovery tower recirculation tank 5, and then sent to the cleaning oil intermediate tank 6. On the other hand, a required amount of new cleaning oil is supplied from the cleaning oil supply tank 7 to the cleaning oil intermediate tank 6, and the cleaning oil is sent from the cleaning oil intermediate tank 6 as regenerated cleaning oil to the degreasing cleaning unit 2.

The canned liquid of the cleaning oil recovery tower 4 contains concentrated PCB and TCB, and is sent to the transformer oil receiving tank 8.

The canned liquid containing concentrated PCB and TCB sent to the transformer oil receiving tank 8 is distilled and separated into a distillate containing TCB and a canned liquid containing PCB in the TCB separation tower 9.

The distillate containing TCB is sent to the TCB separation tower recirculation tank 10 and a part of it is discharged to the outside, but if necessary, it is mixed with the PCB-containing cleaning oil generated by the cleaning of the oil removal cleaning unit 2 and again. It may be separated and distilled.

Further, since the canned liquid containing PCB may contain a small amount of TCB, it is sent to the first distillation column 11 and separated by distillation into the canned liquid containing PCB and the distillate containing a small amount of TCB. ..

The distillate obtained in the first distillation column 11 is sent to the first distillation column recirculation tank 12, and a part of the distillate may be discharged to the outside, or returned to the transformer oil receiving tank 8 and subjected to distillation again. You may.

Further, the canned liquid containing the PCB is sent to a dechlorination facility to remove chlorine from the PCB, and biphenyl is obtained as a product. In the present embodiment, the canned liquid containing PCB does not contain an amount of TCB that consumes an extra palladium catalyst.

FIG. 2 is a processing flow diagram of the conventional device.
The conventional device shown in FIG. 2 is not provided with a PCB and TCB separating device, which is extremely important in the present invention. This is because there is no need to separate them. The reason will be described later.

In FIG. 2, the degreased oil discharged from the degreasing cleaning unit 100 and the PCB-containing cleaning oil are received in the first distillation column 101 and separated by distillation.

The distillate contains trace amounts of PCB, TCB and cleaning oil and water. The canned liquid also contains a thick PCB and a small amount of cleaning oil.

The canned out liquid containing this concentrated PCB and a small amount of cleaning oil is sent to the dechlorination equipment 103.

The distillate containing a trace amount of PCB, TCB and cleaning oil and water is sent to the second distillation column 104, and the canned distillate contains a concentrated PCB. The distillate contains TCB, cleaning oil, and water, and the distillate is sent to the oil removal cleaning unit 100 or the first distillation column 101 as regenerated cleaning oil for reuse.

Therefore, in the processing flow of the conventional apparatus, TCB is concentrated more and more, the concentrations of TCB and PCB fluctuate, the boiling point of the composition fluctuates, and the separation of PCB and TCB becomes very difficult.

This conventional device includes a sodium dispersion tank for storing a sodium dispersion for dehalogenating the PCB-containing cleaning oil and the PCB-containing scrubber oil. Further, the dehalogenation section is provided with a reaction tank for reacting a PCB-containing cleaning oil or a PCB-containing scrubber oil with a sodium dispersion to perform a dehalogenation treatment.

Further, in the conventional device, a solid-liquid separation device for solid-liquid separation of an unreacted sodium dispersion, a mixed solution containing sodium chloride and dehalogenated oil, which has been dehalogenated in a reaction vessel, is provided. I have.

In this conventional dehalogenation section, dechlorination using a palladium catalyst is not performed.

Therefore, it can be understood that in the conventional apparatus shown in FIG. 2, it is not necessary to consider the separation of TCB.

1: Processed product 2: Degreasing and cleaning unit 3: Water separation tower 4: Cleaning oil recovery tower 5: Cleaning and recovery tower Recirculation tank 6: Cleaning oil intermediate tank 7: Cleaning oil supply tank 8: Trans oil receiving tank 9: TCB separation tower 10 : TCB Separation Tower Recirculation Tank 11: 1st Distillation Tower 12: 1st Distillation Tower Recirculation Tank 100: Degreasing Cleaning Unit 101: 1st Distillation Tower 103: Dechlorination Equipment 104: 2nd Distillation Tower

Claims (2)

An oil-draining cleaning unit that accepts and cleans processed products containing PCB, TCB, cleaning oil, and water.
A water separation tower that distills and separates the degreased oil discharged from the degreasing cleaning section and the PCB-containing cleaning oil into a distillate containing water and a can distillate containing concentrated PCB, TCB and cleaning oil.
It is provided with a cleaning oil recovery tower that separates canned liquor containing concentrated PCB, TCB and cleaning oil generated by distillation of the water separation tower into distillate and canned liquor by distillation.
The distillate of the cleaning oil recovery tower contains cleaning oil, and the cleaning oil is sent to the oil removal cleaning unit as regenerated cleaning oil, and the canned liquid of the cleaning oil recovery tower contains concentrated PCB and TCB.
Discharged from a processed product comprising a TCB separation tower that distills and separates the canned liquid of the cleaning oil recovery tower containing concentrated PCB and TCB into a distillate containing TCB and a canned liquid containing PCB. Distillation separation device for TCB contained in PCB-containing cleaning oil. Processed products containing PCB, TCB, cleaning oil and water are accepted into the degreasing cleaning unit for cleaning.
Next, the degreased oil discharged from the degreasing cleaning section and the PCB-containing cleaning oil are received in a water separation tower, and distilled and separated into a distillate containing water and a can distillate containing concentrated PCB, TCB and cleaning oil.
Next, the canned liquid containing concentrated PCB, TCB and cleaning oil generated by the distillation of the water separation tower is received in the cleaning oil recovery tower, separated into the distillate and the canned liquid by distillation, and the cleaning oil is recovered. The distillate of the column contains cleaning oil, and the cleaning oil is sent to the oil removal cleaning unit as regenerated cleaning oil, and the canned solution of the cleaning oil recovery tower contains concentrated PCB and TCB.
Next, the processed product is characterized in that the canned liquid of the cleaning oil recovery tower containing concentrated PCB and TCB is received in the TCB separation tower and distilled and separated into a distillate containing TCB and a canned liquid containing PCB. A method for distilling and separating TCB contained in PCB-containing cleaning oil discharged from.

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