DE3038148A1 - METHOD AND DEVICE FOR TREATING OBJECTS WITH HIGHLY VOLATILE SOLVENTS - Google Patents

Description

GEYER. HAGEMANN & PARTNER

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AMATEN , Soci ^ tfe Anonyitie München, the

35405 SAINT MALO / FRANCE ₉ ^ October 1980

Tau & .: Pafc 179 / 1-80M Dr.G / 2 / Ma

DEVICE FOR TREATMENT OF OBJECTS BIT SCHMER FLOCHTIGEH SOLVENTS

Date: October 10, 1979 Country: France Ref .: 79 25

130017/0745

GEYER, HACcMANiN & PARTNER

PATENT LAWYERS

Γ) ι -.! ·> Ιΐί I) CMwKi- 60 - Posnach 400745 - 80 (X) Munich 40 - Telephone 089/3040 7V - Telex 5-216136 hage d - Telegram hageypatenl - Telecopier 089 304071

Amaten, Societe Anonyme ^v Munich, den

35405 SAINT MALO / FRANCE October 9, 1980

u.z .: Pat 179 / 1-80M Dr.G / 12 / ns

METHOD AND DEVICE FOR TREATMENT OF OBJECTS WITH HEAVY VOLATILE

SOLVENTS

The invention relates to a method for treating Objects with poorly volatile solvents, which stick to the objects towards the end of the treatment Solvent is recovered by using a fan to create a stream of air that traverses the objects brushed over in a drum, loaded with a solvent and then condensed out via a cooling section to be led.

It also relates to a device for treating objects in a solvent medium, with the possibility of doing so the use of non-volatile solvents, in which the objects with the solvent in a rotating Drum are treated and means are provided to move through the drum and the items contained in it to direct a pulsating air flow generated by a fan and this air flow in a condenser to cool at the exit of the drum.

The method and device of the type mentioned are used for cleaning, for Grease removal, for milling, for finishing, for fire protection impregnation or for impermeability impregnation of various objects, such as clothes and fabrics.

After treatment with the solvent comparable to a washing process the objects must be spun and dried, whereby the residual solvent adhering to them by evaporation is recovered. - 6 -

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In known dry cleaning devices, this method carried out in two phases.

In the first phase, the drum or the basket ^{is traversed by an air stream heated to approximately 80 °} C., which is generated by a fan. This air flow takes with it a large part of the solvents, which are recovered by cooling the air flow in a condenser. At a temperature of 80 ^° C., however, there is the risk that stains "burn in" the objects, that fabrics become matted or that fiber layers that have stuck together separate again.

The second phase, also known as odor removal or ventilation, consists in directing a stream of fresh air over the objects to the outside. The temperature of the garments is thereby decreased, but is still about 50 ⁰ C to 55 ° C. This is neither advantageous for the handling nor for the appearance of the objects.

In addition, the known procedure has other disadvantages:

- The energy consumption is very high, on the one hand for heating up the air to be conducted over the objects, on the other hand for the cooling of the air flow,

- the water consumption in the condenser is also high,

- when "venting" an inadmissible environmental pollution occurs,

- The consumption of solvents, which are very expensive, is also great.

Various measures have become known to remedy these disadvantages. After a suggestion, the air will be out of the "Ventilation process" passed through adsorbents, such as activated charcoal, in order to recover the solvent and avoid environmental pollution. However, when regenerating the activated carbon, this process consumes a lot Energy.

It has also become known that the commonly used solvent perchlorine

Pat 179 / 1-80M 130017/0745

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Replace ethylene with more volatile solvents (fluorinated solvents) in order to reduce energy consumption. However, these solvents are expensive and of mediocre effectiveness. Their low boiling point causes losses through unwanted evaporation. Therefore, they are generally little and only for special applications, such as for cleaning of leather and hides and very sensitive objects used. To improve the use of these volatile solvents, it has become known to condense out the

To use the refrigerant of a refrigeration machine whose condenser is used to reheat the solvent. One such unit represents a closed thermodynamic System, where the refrigeration machine acts as a heat pump, 5 transferring the heat from the solvent condenser to the reheating device transfers (FR-PS 2 035 303, US-PS 3070 463). Ventilation is not necessary because the operating temperature of the condenser is low enough to allow complete recovery of the solvent in the closed Enable circulation. This way there will be some energy saving and a reduction in environmental impact achieved. However, this solution is not suitable for poorly volatile solvents such as perchlorethylene, Trichlorethylene, trichloroethane, etc. It is known for the latter become a condenser with cold liquid or to use a water-cooled condenser in conjunction with a condenser with cold liquid, both of which Capacitors can be connected in parallel or in series.

According to FR-PS 2 130 523, the cooled condenser is used for "venting", while the solvent is recovered in the usual way. The cooled condenser is arranged in parallel above the reheating device. According to FR-PS 2 293 513, the cooled condenser is connected downstream of the water-cooled condenser in order to lower the temperature of the air and lower the limit for the saturation concentration of the solvent. During this phase, the air re-heater is short-cut .79 / 1 -8 (w 130017/0745 " ⁸ ~

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closed.

In this way, a saving in the consumption of solvent is achieved with poorly volatile solvents and the Reduced environmental impact. As before, the problem of saving energy is not solved, since cooling the condenser additional energy is consumed. The water consumption also remains high.

The invention is based on the object of specifying a method of the type mentioned at the outset that uses low-volatility Solvents can work and avoid environmental pollution through as complete recovery as possible of the solvent while consuming as little energy and water as possible. Likewise, that should be items to be treated are treated as gently as possible.

This object is achieved in that the air flow in a closed Circuit starting from the drum via an evaporator and then via the condenser of a refrigeration machine, which is in the high-pressure part of the Refrigerant circuit s downstream of the compressor has an auxiliary condenser acted upon by water or pulsating air, and that in two Phases is worked, a first phase in which the auxiliary capacitor is not charged and a second phase in which the auxiliary capacitor ~ is applied so that the air temperature at the entrance of the Trcranel is lowered by at least 10 ° C to 30 ° C in the course of the second phase.

In said first phase, especially if perchlorethylene is used as solvent, the temperature of the incoming air into the drum at 55 ° C is brought to 60 ⁰ C. An advantageous further development of the invention is characterized in that this increase in temperature of the air entering the drum is accelerated in the first phase with the aid of an additional heater, which has a thermostat that switches off after the target temperature has been reached, and that the operation of the additional or auxiliary

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heating is stopped for the entire duration of the second phase. This way the total uptime can be significantly reduced and the system can be better used. It is particularly advantageous if the auxiliary heater has a Has thermostat to prevent overheating.

According to a further advantageous procedure, the additional heating is regulated in the first phase in such a way that the air has a temperature of approximately 50 ^° C. and the evaporator has a temperature of approximately 0 ^° C. before it enters the drum. In this way, the most complete possible recovery of the solvent is achieved with gentle treatment.

In the second phase, the auxiliary capacitor is used to control the temperature reduce the air entering the drum, be it by the fact that the temperature of the condenser of the Kaitmaschine is reduced, or by the fact that the auxiliary capacitor takes over the role of the latter and short-circuits it.

The temperature of the evaporator drops to below -TO ⁰ C and the solvent residues are practically completely recovered, while the items of clothing are cooled when they are removed from the basket drum *.

The following advantages result:

- Possibility of using relatively poorly volatile solvents,

- Energy saving,

- saving water,

- saving of solvents,

- Avoidance of pollution.

A simple and at the same time particularly effective variant of the method provides that the auxiliary condenser with water from Ambient temperature is applied.

To avoid overheating or excessive pressure in the

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In the first phase, it has proven to be particularly advantageous to use the auxiliary condenser of the refrigeration machine as a safety device to operate. To this end, according to an advantageous embodiment of the method according to the invention provided that the auxiliary capacitor in the first phase as a safety device for regulating the temperature or the pressure in the high-pressure part of the refrigeration machine by means of one of the aforementioned Pressure or the said temperature controlled valve is used.

Furthermore, the invention is based on the object of creating a device of the type mentioned in the introduction, with which the method according to the invention can be carried out.

This object is achieved in that the air flow forms a closed circuit, that the air flows over the evaporator of a refrigeration machine, which has means for recovering the solvent, that the air subsequently flows over the condenser of the refrigeration machine and through the action of a fan is conveyed back to the drum that an auxiliary condenser is arranged behind the compressor in the refrigerant circuit of the refrigerating machine, that the auxiliary condenser is dimensioned so that it lowers the temperature at the entrance of the drum by at least 10 ⁰ C to 30 ⁰ C when it is in operation is taken, and that means are provided by which the operation of the auxiliary capacitor can be interrupted in a first phase and switched on in a second phase.

The device according to the invention is thus a closed one Air circulation provided with a fan. The evaporator of a refrigeration machine serves as the condenser for the solvent.

An embodiment with which the start-up phase and thus the

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Energy consumption can be kept small, stands out
characterized in that an auxiliary heater with a thermostat controller is arranged in the air stream downstream of the condenser of the refrigeration machine and that the auxiliary heater is a
Has switching device by means of which it can be switched on exclusively during the temperature rise in the first phase and then switched off and during the entire second phase.

A device in which the auxiliary capacitor is particularly advantageous because of its low expenditure in terms of apxjarat
connected in series with the condenser of the chiller
and has devices for passing a coolant through during the second phase and in which the devices can interrupt the flow of the coolant during the first phase.

On the other hand, in terms of control technology, there is a device Proven to be particularly favorable in which the auxiliary capacitor is connected in parallel to the capacitor of the refrigerating machine is and the flow of the pressurized refrigeration cycle medium through valves on those arranged in the air flow Capacitor during the first phase or on the auxiliary capacitor can be switched during the second phase.

Finally, the auxiliary capacitor can advantageously be used as a safety device in the first phase.
A device in which the high-pressure part of the refrigerating machine is secured against excessive temperature and pressure increases in this way is characterized in that the auxiliary condenser is additionally used as a safety device during the first phase
to regulate the temperature or the pressure in the high-pressure part of the refrigeration machine by means of a through the said
Temperature or the mentioned pressure controllable valve is used.

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The invention is explained in more detail below with reference to the exemplary embodiments shown schematically in the figures. Show it:

Figure 1:
a process scheme of a first embodiment

Figure 2:

a process scheme of a second embodiment.

From the scheme shown in Figure 1 it can be seen that the device has a basket or drum 1, in which is blown in by a fan 5 air. For the sake of simplicity, the drawing shows only a circular one Outlined, when in reality it is a closed container with a rotating basket drum inside is arranged with a circular cross-section.

In the air discharge 15 of the basket drum there is a Dust filter 2. From the outlet side of filter 2, the air is passed through an evaporator .3 of a refrigeration machine, which serves as a condenser for the solvent which is recovered at its nozzle. The solvent-free Air is passed over the condenser 4 of the mentioned refrigeration machine, whereby the air is heated and then through the Fan 5 is conveyed back to the basket drum 1. The air circulates in a closed circuit.

The refrigeration machine has a compressor unit 7 which, via line 21, supplies a refrigerant such as fluorinated (halogen) hydrocarbon compounds (Freon) in the condenser 4, where the refrigerant is cooled in heat exchange with the air flow. Stream from there it into the evaporator 3 after an expansion in the throttle valve. The refrigerant then flows back to the compressor via a line 20 7. In a heat exchanger 8, the refrigerant flow exiting the compressor is exchanged for heat with that to the compressor

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ORIGINAL INSPECTED

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returning refrigerant flow cooled. As is known, the heat exchanger 8 by a gap or a capacity between the Compressor 7 and the condenser 4 are replaced. In the refrigerant line between the condenser 4 and the evaporator s -> there is a dehumidifier 9 and a liquid sight glass 10.

This unit represents a heat pump with an additional condenser 12 / which is arranged upstream of the condenser 4 and which is operated with cold water as a coolant. This flows controlled by the valve 13 through the line 17th

In addition, there is between the fan 5 and the basket drum 1 an auxiliary or booster heater 6, for example one Resistance heating, provided with a thermostat regulator is equipped. The thermostat controller can, for example, have a temperature sensor (not shown).

The operating mode is as follows:

1st phase.
The following are switched on at the same time:

- the compressor unit 7, without water circulation in the auxiliary condenser 12;

- the fan 5;

the auxiliary heater 6, regulated to a temperature of about 50 ° C.

The air flowing in the closed circuit is heated by the condenser 4 and then by the auxiliary heater 6, see above that the temperature at the entrance of the basket drum rises rapidly to about 50 ° C. This temperature rise will be in a few

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Minutes (approx. 3-5 minutes) and the auxiliary heating can then be switched off: This is followed by heating exclusively through the main condenser of the chiller.

When flowing through the basket drum and the objects in it, the air is saturated with solvent, which leads to leads to a decrease in temperature. The temperature of the air flow at the outlet of the basket drum is around 30 ° C - 45 ° C. The air flow enters the dust filter 2, then into the Evaporator 3 of the refrigeration machine, which is at a temperature level of around 0 ° C.

This phase lasts about 15-20 minutes, and at least 95% of the solvent are recovered.

To avoid any overpressure in the chiller, a valve 14 is provided which is provided with a control device. The control device either comprises a temperature sensor 18 in the air outlet line of the condenser 4 or a pressure sensor 19 in the output line of the compressor 7. Through the valve 14, the condenser 12 is cold Water is applied, whereby the pressure in the high pressure part the refrigerator is kept below a predetermined maximum. The valve 14 is to the main valve 13, in the coolant supply line of the condenser connected in parallel so that the auxiliary condenser 12 is supplied with cooling liquid even when the valve 13 is closed can be applied.

2nd phase.

Following this first phase, the temperature equilibrium is shifted by actuating the valve 13, the auxiliary capacitor exposed to water and the auxiliary heating 6 is switched off.

The air flowing into the basket drum 1 via the fan 5 gradually cools down to a temperature of less than 30 ° C. Therefore it becomes a little - i.e. by a few degrees - due to the items of clothing in the basket drum

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warmed up: The temperature of the air in the evaporator 3 is noticeable about -15 ° C, and those left in the garments Solvent residues are condensed.

When the drum open at the end of the passage is the temperature of the goods below 30 ° C (this is favorable for the handling and the external appearance of the articles) _f and its solvent content during the opening of the drum is less than 100 ppm (parts per million) The advantages of the invention are clear from the following comparison table / in which various devices that work with perchlorethylene are compared. It means: A = consumption

B = classic device that holds 10 kg of clothes per run treated,

C = device with cooled condenser; 10 kg / treatment cycle D = device according to the invention with 10 kg / treatment cycle.

A. B. (kWh) C. (kWh) D. 1.54 (kWh) Electric 32 4.33 energy (D (D 43 (D water 100 (G) 96 (G) 150 (G) solvent 750 180

The diagram in FIG. 2 differs from the diagram in FIG. 1 in the position of the auxiliary condenser 12 in the refrigerant circuit .

While in the scheme shown in Figure 1, the auxiliary con-

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capacitor 12 arranged in series with the capacitor 4 and is connected upstream of this, the auxiliary capacitor is in the scheme 2 connected in parallel with the capacitor 4. The refrigerant escaping from the compressor can be controlled with the help of the valves 22 and 23, which are each located in the two parallel branches, either via the condenser 4 (valve 22 open, valve 23 closed) or via the condenser 12 (valve 22 closed, valve open). The transition from the first to the second The phase is consequently carried out by actuating the valves and 23 as well as by actuating the valve 13 in the water supply line of the condenser 12. An additional valve 24 can be provided in the branch containing the auxiliary condenser in order to prevent the To control the flow rate of the freon or another refrigerant and consequently the temperature in the evaporator 3. In the second phase, the capacitor 4 is used in this variant of the method not acted upon and the air flowing through it is not heated. Consequently, the Reduced temperatures of the air flow along its flow path.

Refer to the calculation data from the previous description on perchlorethylene, the most widely used solvent; there are solvents whose boiling point does not go far from the boiling point of perchlorethylene. If other solvents are used, the optimum process temperatures can be used for each phase as well as the properties of the refrigerant to be used are easily determined through tests will. The method and the device according to the invention are easily adaptable to such conditions.

Although the method and the device according to the invention have been designed to create the possibility of To use poorly volatile solvents, easily volatile solvents can nonetheless also be used.

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Claims (11)

MANN & PARTNER hrv.ti.ii · «· 60 · PdstMc h 400745 - 8'KlO Munich 40 -Telpton 089.304071" · Telex 5-216136 hage d -Telegram hageypatent · Telekupierer 089-30407 "AMATEN, Societe Anonyme Munich, 35405 SAINT MALO / FRANCE October 9, 1980 oc: Pat 179 / 1-8ΌΜ Dr.G / 2 / Ma CLAIMS 1. Method of treating objects with poorly volatile solvents, in which the solvent adhering to the objects towards the end of the treatment is recovered by placing the items in a drum to contain the remaining solvent be exposed to a stream of air, which is then passed through a cooling section to condense the solvent is characterized in that the air flow in a closed circuit starting from the drum (1) Via the evaporator (3) and the condenser (4) of a refrigeration machine is performed, which is in the high pressure part of your refrigerant circuit behind the compressor with an auxiliary condenser (12) is provided, the coolant supply of which is interrupted in a first phase and in a second phase is adjusted so that the temperature of the air stream entering the drum (1) to at least 10 ° C to 30 ° C is lowered. 130017 / 074S 2. The method according to claim 1, characterized in that the auxiliary capacitor (12) with water or with a pulsating air flow is applied. 3. The method according to claim 1 or 2, characterized records that the temperature rise of the entering the drum Air is accelerated in the first phase with the help of an additional heater (6) and that the operation of the additional heater (6) is discontinued for the entire duration of the second phase. 4. The method according to claim 3, characterized in that the additional heating is regulated so that the air has a temperature of about 50 ° C and the evaporator (3) has a temperature of about 0 ⁰ C before entering the drum (1). 5. The method according to any one of claims 1 to 4, characterized in that the auxiliary capacitor (12) with water from Ambient temperature is applied. 6. The method according to any one of claims 1 to 5, characterized in that the auxiliary capacitor (12) in the first Phase when temperature or pressure increases in the high-pressure part of the refrigerant circuit of the refrigeration machine is acted upon with coolant. 7. Device for treating objects with poorly volatile solvents with a rotating Drum, with a housing surrounding the drum, which has an input and an output connection for passage comprises an air flow generated by a fan, and with means for cooling the air flow in one Solvent condenser at the outlet of the drum, characterized in that the outlet connection of the housing of the Pat 179 / 1-80M - 3 - Amates 130017/0745 Drum (T) via a pipe to the evaporator (3) a refrigeration machine is connected, which has a discharge nozzle (16) has for condensed solvent that the evaporator (3) via a further pipe with the The condenser (4) of the refrigeration machine is connected to that of the condenser (4) is connected to the air inlet connection of the housing of the drum (1) that in the line downstream of the compressor (7) of the refrigeration machine, an auxiliary condenser (12) is arranged, which is dimensioned so that with it the temperature of the entering the drum (1) Air can be lowered to at least 10 ° C to 30 ° C, and that the coolant admission to the auxiliary condenser (12) can be interrupted in a first phase and switched on in a second phase with the aid of a valve (.13). 8. Apparatus according to claim 7, characterized in that in the pipeline downstream of the condenser (4) the refrigerating machine has a heating device (6) with a thermostat controller and that the heating device (6) has a switching device by which it can be switched on during the temperature rise in the first phase and can then be switched off as well as during the entire second phase. 9. Apparatus according to claim 7 or 8, characterized in that the auxiliary capacitor (12) in series with the Condenser (18) of the refrigeration machine is arranged and means for passing a coolant during the second phase, and that the flow of coolant can be interrupted by the devices during the first phase is. 10. Apparatus according to claim 7 or 8, characterized in that the auxiliary capacitor (12) is arranged parallel to the capacitor (18) of the refrigerating machine ISt _x and that Pat 179 / 1-80M ⁴ Amates 130017/0745 the flow of pressurized refrigeration cycle media through valves (23, 22) on the condenser (4) during the first phase or on the auxiliary condenser (12) during the second phase is switchable. 11. Device according to one of claims 7 to 10, characterized characterized in that in a coolant feed line of the auxiliary condenser (12) a valve (14) with a control unit is arranged, which is arranged with a temperature or pressure sensor arranged in the high-pressure part of the refrigeration machine (18, 19) is connected so that the valve (14) when it is reached a certain temperature or a certain pressure in the high pressure part of the refrigeration machine opens and the Auxiliary condenser (12) is acted upon with coolant. Pat 179 / 1-80M Amates 130017/0745