JPH0363478A - Fluorocarbon recovery device - Google Patents

Abstract

PURPOSE:To enable an amount of fluorocarbon liquid within a final recovery tank to be acknowledged from outside without applying any special machining work to the final recovery tank by a method wherein a liquid sensor is arranged at a mean pressure pipe for releasing a pressure corresponding to a volume of liquified fluorocarbon supplied to a final recovery tank. CONSTITUTION:Gaseous fluorocarbon taken out of a second outlet 16b of a primary recovery tank 16 is supplied to a condensing device 18b of a two-system heat exchanger 18 through a pipe 12. In this case, the gaseous fluorocarbon is cooled and liquified under a thermal absorbing action at an evaporating system 18a. The liquified fluorocarbon is recovered to a final recovery tank 19 through a pipe 12. A condensing side 18b of the two-system heat exchanger 18 and the final recovery tank 19 are connected by a mean pressure pipe 20. A pressure within the take is increased by an amount corresponding to a volume of liquified fluorocarbon. However, this pressure is released through the mean pressure pipe 12 and the pressure within the final recovery tank is always kept at a substantial constant value. The fluorocarbon liquid ascending within the mean pressure pipe is detected by a liquid sensing means 21 arranged in the means pressure pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a device for recovering fluorocarbon gas used as a refrigerant in a refrigeration circuit of an air conditioner (hereinafter referred to as an air conditioner) for an automobile, for example.

[Prior Art] In automobile coolers or air conditioners, Freon is used as a refrigerant in the refrigeration circuit. When this CFC is released into the atmosphere, it has a negative impact on the ozone layer surrounding the earth. For this reason, for example, when scrapping a car or repairing a car cooler or air conditioner, it is necessary to prevent fluorocarbon gas from being released into the atmosphere, and to reuse fluorocarbons, which are produced in limited quantities, by removing fluorocarbons from the refrigeration circuit. need to be collected. Conventionally, in order to recover fluorocarbons, a compressor or pump has been used to extract the fluorocarbons from the material to be recovered and pour them into a recovery container for recovery.

Conventional fluorocarbon recovery equipment uses a compressor to suck in the recovered fluorocarbons, condenses them into a liquid in a condenser, and collects them in a recovery tank. The recovery tank was equipped with a sight glass so that the amount of liquefied fluorocarbons recovered could be identified from the outside.

[Problems to be Solved by the Invention] In conventional equipment, a sight glass was installed in the recovery tank so that the amount of recovered liquefied fluorocarbon could be identified from the outside. The structure of the tank becomes complicated and costs increase.

Therefore, an object of the present invention is to provide a fluorocarbon recovery device that allows the amount of fluorocarbon liquid in the final recovery tank to be identified from the outside without performing any special processing on the final recovery tank.

[Means for Solving the Problems] According to the present invention, recovered fluorocarbons are sucked by a compressor, discharged, condensed and liquefied by a condenser, and stored in a primary recovery tank, and the fluorocarbons recovered in this primary recovery tank are converted into gaseous fluorocarbons. After coming out of the primary recovery tank, the liquid Freon is supplied to the evaporation side of the two-system heat exchanger through an expansion valve, and the Freon taken out to the outlet side is sucked into the compressor. The gaseous fluorocarbons in the primary recovery tank are supplied to the condensing side of the two-system heat exchanger and then recovered in the final recovery tank.
The system heat exchanger and the final recovery tank are connected by piping to supply the liquefied fluorocarbon accumulated in the two-system heat exchanger by its own weight, and the pressure corresponding to the volume of the liquefied fluorocarbon supplied to the final recovery tank is A fluorocarbon recovery device is obtained, which is connected to a fluorocarbon recovery device by a pressure equalizing pipe for escaping, and is characterized in that the pressure equalizing pipe is provided with a liquid sensing means.

[Function] The fluorocarbons taken out from the part to be recovered are sucked and discharged by the compressor, supplied to the condenser, liquefied, and stored in the primary recovery tank. The fluorocarbons recovered in this primary recovery tank are separated into gas and liquid. The separated liquid exits the primary recovery tank and is supplied to the evaporation side of the two-system heat exchanger through an expansion valve [7], and the fluorocarbon taken out to the outlet side is returned to the suction steel of the compressor.

On the other hand, the gaseous fluorocarbons separated in the primary recovery tank are supplied from the primary recovery tank to the condensing side of the two-system heat exchanger, where they are liquefied. The liquefied Freon is supplied by its own weight from the two-system heat exchanger to the final recovery tank via piping. As the liquefied fluorocarbon is supplied to the final recovery tank, the pressure inside the tank increases by the volume of the liquefied fluorocarbon, but this pressure is released through the pressure equalization pipe, and the pressure in the final recovery tank is always kept almost constant. .

The fluorocarbon liquid is accumulated in the final recovery tank, but when the liquid level reaches one end of the pressure equalizing pipe located above the final recovery tank, the fluorocarbon liquid rises in the pressure equalizing pipe due to the tank internal pressure. The fluorocarbon liquid rising in the pressure equalizing pipe in this manner is detected by a liquid sensing means provided in the pressure equalizing pipe.

Further, since one end of the pressure equalizing pipe is located below the upper end of the final recovery tank, when fluorocarbon liquid is detected, fluorocarbon gas remains in the upper part of the final recovery tank. Therefore, even if the final recovery tank is heated after refrigerant recovery, there is no sudden increase in pressure due to liquid expansion.

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

FIG. 1 is a schematic configuration diagram showing the overall configuration of a fluorocarbon recovery device according to an embodiment of the present invention. Although not shown, the part to be recovered is, for example, an air conditioner circuit of an automobile, and the liquid or gaseous fluorocarbon contained therein is supplied from the inlet 11 of the recovery device to the suction steel of the compressor 13 via the pipe 12. The compressor 13 compresses the sucked gaseous Freon and supplies it to the discharge side.

A condenser 14 is connected to the discharge side of the compressor 13. In the condenser 14, the fluorocarbon gas is cooled and liquefied. The liquefied Freon is supplied from the outlet of the condenser 14 to a filter/dryer 15, where impurities, moisture, acid, etc. are removed, and then supplied to a primary recovery tank 16.

The primary recovery tank 16 includes first and second outlets 16a and 16b. Liquid fluorocarbon is taken out from the first outlet 16a, and gaseous fluorocarbon is taken out from the second outlet 16b. Liquid freon is sent to the expansion valve 17 via piping 12.
The water is supplied to the evaporation side of the two-system heat exchanger 18 via. The expansion valve 17 is an automatic expansion valve whose opening degree is adjusted to two depending on the pressure on the outlet side of the two-system heat exchanger 18.

The two-system heat exchanger 18 includes an evaporation system 18g where liquid Freon is supplied and vaporized, and a condensation system 18b where gaseous Freon is supplied and cooled and liquefied, and heat exchange is performed between these two circuits. This is what we do. The liquid Freon supplied to the evaporation system 18a is vaporized here and returned to the suction steel of the compressor 18 via the piping 12.

On the other hand, the gaseous fluorocarbon taken out from the second outlet 16b of the primary recovery tank 16 is supplied to the condensing side 18b of the two-system heat exchanger 18 via the pipe 12.

Here, the gaseous Freon is cooled and liquefied by the endothermic action in the evaporation system 18a. The liquefied fluorocarbon is piped into pipe 12.
The collected waste is collected in the final collection tank 19 via.

The condensing system 18b of the two-system heat exchanger 18 and one final recovery tank are connected by a pressure equalizing pipe 20. The inner end 21a of the pressure equalizing pipe 20 in the final recovery tank 19 is located slightly below the upper end of the final recovery tank 19. A liquid detection means 21 is provided in a portion of the pressure equalization pipe 20 led out to the outside of one final recovery tank. As this liquid detection means 21, a sight glass, a float type microswitch, or the like can be used.

Therefore, the fluorocarbon liquid liquefied on the condensing side 18b of the two-system heat exchanger 18 flows into the final recovery tank 19 via the pipe 12 due to its own weight. As the liquefied fluorocarbon is supplied to the final recovery tank 19, the pressure inside the tank increases by the volume of the liquefied fluorocarbon, but this pressure is released through the pressure equalization pipe 12, and the pressure in the final recovery tank is always kept almost constant. It is maintained.

Further, the fluorocarbon liquid is accumulated in the final recovery tank, but when the liquid level reaches one end of the pressure equalizing pipe located above the final recovery tank, the fluorocarbon liquid rises in the pressure equalizing pipe due to the tank internal pressure. The fluorocarbon liquid rising in the pressure equalizing pipe in this manner is detected by a liquid sensing means provided in the pressure equalizing pipe.

Note that since one end of the pressure equalization pipe is located below the upper end of the final recovery tank, fluorocarbon gas remains in the upper part of the final recovery tank at the time when the fluorocarbon liquid is detected. Therefore, even if the final recovery tank is heated after refrigerant recovery, there is no sudden increase in pressure due to liquid expansion.

[Effects of the Invention] According to the present invention described above, the amount of fluorocarbon liquid in the final recovery tank can be identified from the outside by simply processing the pressure equalizing pipe without performing any special processing on the final recovery tank. Therefore, the cost of the final recovery tank can be reduced.

FIG. 1 is a schematic configuration diagram showing the overall configuration of a fluorocarbon recovery device according to an embodiment of the present invention.

11: Inlet, 12: Piping, 13: Compressor,
14: Capacitor, 15: Filter/dryer, 16:
Primary recovery tank, 17: expansion valve, 18: two-system heat exchanger, 19: final recovery tank, 20: pressure equalization pipe, 21: liquid detection means.

[Brief explanation of drawings]

Claims (1)

[Claims] 1. The recovered fluorocarbons are suctioned by a compressor, discharged, condensed and liquefied by a condenser, and stored in a primary recovery tank. In this primary recovery tank, the recovered fluorocarbons are divided into gaseous fluorocarbons and liquid fluorocarbons, and the liquid fluorocarbons are After leaving the recovery tank, it is supplied to the evaporation side of the two-system heat exchanger via an expansion valve, and the gas taken out to the outlet side is returned to the suction steel of the compressor, and the gaseous Freon in the primary recovery tank is After being supplied to the condensing side of the two-system heat exchanger, it is collected in a final recovery tank, and the two-system heat exchanger and the final recovery tank collect the liquefied fluorocarbon accumulated in the two-system heat exchanger by their own weight. The recovery device is connected by a supply pipe and is also connected by a pressure equalization pipe for releasing the pressure corresponding to the volume of liquefied fluorocarbon supplied to the final recovery tank, characterized in that the pressure equalization pipe is provided with a liquid sensing means. Freon recovery equipment.