WO2012168078A2 - Cooling by steam jet generation - Google Patents

Abstract

The invention relates to a steam jet refrigeration machine (1) that uses an ionic liquid as a propellant (F), whereby particularly effective cooling can be achieved. The steam jet refrigeration machine (1) is particularly suitable for household appliances (air conditioning systems, refrigerators, etc.) and motor vehicles (air conditioning systems in automobiles, etc.). The method is used for operating a steam jet refrigeration machine (1) using a refrigerant (K) and a propellant (F), said propellant (F) being an ionic liquid.

Description

description

The invention relates to a steam jet cooling machine for evaporation of a refrigerant Ver by means of a negative pressure using a steam jet of a blowing agent. The dung OF INVENTION ^¬ further relates to a method for operating a steam jet ejector chiller. The invention may in particular for Küh len of household appliances, such as air conditioning, in particular home appliances such as refrigerators, freezers, etc., are used, but also for cooling of or on vehicles, for example, as air conditioning of a motor vehicle. There are steam jet cooling machines are known in which cold is generated by boiling water used as a cooling liquid at low pressure in an evaporator and thereby cools the remaining liquid in the evaporator water. This negative pressure is generated by means of a steam jet nozzle fluidically connected to the evaporator. Vaporous water as a blowing agent which is conducted at a high speed through a steam jet nozzle ^¬ USAGE to the steam jetting nozzle ^¬ det. Due to the high speed of the propellant in the steam jet nozzle there arises a Un terdruck, since the total pressure in the steam jet refrigerator remains constant. The negative pressure in the steam jet nozzle serves to generate the negative pressure in the evaporator connected to the steam jet nozzle. The negative pressure that can be reached in the evaporator is limited by the vapor pressure of the water. This is practically a limit of a pumping power given, which is also a lower Tempe raturgrenze for remaining in the evaporator liquid water and thus for a cooling capacity of the steam jet cooling ^¬ machine. This leads to a limited working area of the steam blast chiller.

It is the object of the present invention to provide a verbes ^¬ serte steam jet ejector machine, in particular with a highs ren work area and / or a higher cooling capacity to provide.

This object is achieved according to the features of the independent claims. Preferred embodiments are insbesonde ^¬ re the dependent claims.

The object is achieved by a steam jet chiller for evaporating a refrigerant by means of a negative pressure using a steam jet of a blowing agent, wherein the blowing agent is an ionic liquid. An ionic liquid has the advantage that it has only a very low vapor pressure, so that it is possible to achieve particularly low pressures (high overpressure) with the steam jet nozzle. As a result, the working range of a steam blast chiller can be widened, thus increasing its cooling capacity. In this case, a simple construction of a conventional steam jet refrigeration machine can be maintained. It is a development that the ionic liquid contains liquid salt or liquid salts. The ionic liquid may contain, in particular cationic salts and / or anio ^¬ African salts. A cationic salt, which in particular may be alkylated, may in particular comprise imidazolium, pyridinium, pyrrolidinium, guanidinium, uronium, thiouronium, piperidinium, morpholinium, ammonium and / or phosphonium. In particular, ammonium and its derivatives may also be dispensed with. Suitable anions or anionic salts are, in particular, halides and more complex ions, such as tetrafluoroborates, trifluoroacetates, triflates, hexafluorophosphates, phosphinates and / or tosylates. Organic ions, such as, for example, imides and amides, can also be anions or anionic salts. The ionic liquids are typically thermally stable, non-flammable and have a very low, barely measurable vapor pressure. For example, by a variation of the side chains of the cation and / or a selection of suitable anions, the solubility in water or organic solvents can be largely determine freely. The same applies to the melting point and the viscosity. By appropriate functional groups they can be synthesized as acids, bases or ligands. It is an embodiment that the refrigerant is a liquid ^¬ ness with a lower boiling point than water. Thus, in particular in combination with the ionic liquid as the propellant, evaporative cooling of the refrigerant already takes place at a comparatively lower negative pressure, whereby the cooling capacity of the steam blast chiller can be increased even further.

Alternatively, the refrigerant may also be an ionic flues ^¬ sigkeit, in particular the same ionic liquid, which is already used as the propellant.

It is still an embodiment that the refrigerant comprises alcohol, in particular ethanol. Alcohol is low-boiling, inexpensive and (especially in the form of ethanol) not toxic.

It is yet another embodiment that the propellant is heavier than the refrigerant. Thus, the Treibmit ^¬ tel can settle in its liquid state of aggregation bottom side, in particular in an evaporator, and so particularly easy to be transported to the steam jet.

It is also an embodiment that the blowing agent and the refrigerant are immiscible, i. do not form a mixture. Thus, a separation in its liquid state, in particular in an evaporator, can be achieved easily.

It is also a development that a boiling temperature of the refrigerant is lower than a boiling temperature of the blowing agent. Thus, a suction of the refrigerant in the steam jet nozzle is made possible in high purity. It is also an embodiment that the steam jet chiller comprises at least the following components: (i) a jet nozzle having a blowing agent port, a suction port and a mixed flow outlet, (ii) a condenser connected to the mixed flow outlet of the jet nozzle, and (iii) one with the liquefier wherein the evaporator has a blowing agent outlet and a refrigerant outlet, wherein (iv) the blowing agent outlet is connected via a conveying unit to the blowing agent port of the jet nozzle and the refrigerant outlet is connected to the suction port of the jet nozzle. This Ausgestal ^¬ tion allows a simple and effective construction of a steam jet refrigerator.

The condenser may be connected to the evaporator, in particular via a valve.

It is yet another embodiment that the evaporator is designed as a heat exchanger. Thus, the steam blast chiller can be easily used as a flexible refrigeration unit. Alternatively, may also be cooled directly by a flow of the refrigerant or of the blowing agent to a cow ^¬ loin device for example.

It is still an embodiment that the propellant located in the evaporator is used as a heat exchange medium ^¬ bar. It is therefore not used in the evaporator directly cooled by the heat of vaporization heat extracted refrigerant as a heat exchange medium. This has the advantage that the blowing agent is due to the heat exchange at an elevated temperature relative to the refrigerant, which facilitates evaporation of the blowing agent in the jet nozzle.

The invention can be used in particular for cooling household appliances, eg air conditioning systems, in particular domestic appliances such as refrigerators, freezer devices, etc. However, the invention is not limited thereto and may, for example, also for vehicles, eg for air conditioning systems of trains or motor vehicles, are used.

The object is further achieved by a device, wherein the device has at least one steam blast chiller on ^¬ , in particular as a refrigeration device or a refrigeration unit. The device may be, for example, a domestic appliance, in particular a domestic appliance, or a vehicle.

The object is also achieved by a method for Betrei ^¬ ben a steam blast chiller using a refrigerant and a propellant, wherein the propellant is an ionic liquid. This gives the same advantages as the steam blast chiller. The method can also be designed analogously to the steam blast chiller ^¬ the.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following schematic description of an embodiment, which will be described in more detail in conjunction with the drawings. The same or equivalent elements can be provided with the same Bezugszei ^{¬ Chen} for clarity.

The figure shows tekreislauf to a possible design of a steam-jet refrigeration unit 1 Inventive ^¬ proper with its associated coldest. During operation of the steam-jet refrigeration unit 1, a conveying unit pumps in the form of a pump 2 Treibmit ^¬ tel in the form of an ionic liquid F with high pressure from an evaporator 3 5. In the evaporator 3 are located at a blowing agent port 4 of a nozzle, the ionic liquid F and a refrigerant K in the form of alcohol. Of the blowing agent port 4, the ionic liquid F is a drive nozzle (o.Abb.) Gelei ^¬ tet in the form of a Laval nozzle from which the ionic liquid F with high overall speed as steam in a mixing chamber 5a of the Strahldü ^¬ se 5 exits and generates a high negative pressure there. This negative pressure is not limited by the (practically negligible) vapor pressure of the ionic liquid F. The mixing chamber 5a is fluidically connected to a refrigerant outlet 8 of the evaporator 3 via a fluid line 6 connected to a suction connection 7, specifically with the area of the evaporator 3 containing the refrigerant K. Consequently, the evaporator 3 is subjected to negative pressure, and that in FIG The refrigerant K present in the evaporator 3 evaporates early due to its low boiling point. The ionic flues ^¬ sigkeit F remains, which has a higher boiling point.

The vaporized refrigerant K is sucked via the fluid line 6 into the mixing chamber and mixed there with the vaporized ionic liquid F. The resulting mixed jet F, K is in a downstream diffuser of the jet nozzle 5, which also acts as Gemischtstromauslass 12, delayed. The mixed jet F, K is passed on to the mixed flow outlet 12 further into a condenser 9. This can be embodied, for example, as a heat exchanger or as a mixed condenser. The condenser 9 may be air-cooled and / or liquid-cooled. In the condenser 9, the mixed jet F, K is liquefied or condensed. The resul ^¬ animal condensate F, K from the ionic liquid F and the refrigerant K is forwarded to a valve 10 and expanded there. The valve 10 is followed by the evaporator 3, in which the condensate F, K runs. In the evaporator 3, the condensate F, K separates, with the heavier ionic liquid F sinking down. In a region of the bottom of the evaporator 3, in which the ionic liquid F is located, there is a propellant connection 13, via which a connection line 11 to the pump 2 is connected. The fluid line 6 is at an upper portion of the evaporator 2 connected to which vaporous refrigerant K is located.

By the vacuum evaporation of the refrigerant K in the evaporator 3, the temperature of the still liquid refrigerant 3 and thus also the ionic liquid F decreases. The evaporator 3 can be used in a variant as a heat exchanger, for example by a separate or secondary cooling circuit S through the evaporator. 3 runs, with a coolant M flows in the secondary cooling circuit S. The o.ä. Coolant M cooled by the evaporator 3 can be conveyed to a device to be cooled (for example, an air conditioner or a refrigerator, etc.). The secondary cooling circuit S may in particular be in a heat exchange with the ionic liquid F as a heat exchange medium, but alternatively or additionally with the refrigerant K.

The steam jet cooling machine 1 shown has as a further advantage that only the pump 2 is a movable part in operation and the steam jet cooling machine 1 is therefore effective, simple, inexpensive and low maintenance.

Although the invention has been illustrated in detail, for example approximately detail by the execution shown and described, the invention is not limited thereto and other Variatio ^¬ NEN can be derived therefrom by the skilled artisan without departing from the scope of the invention. Thus, the steam jet chiller shown also more

Have components, e.g. Sensors and / or a control device.

Also, the components shown may be replaced by functionally similar or equivalent components.

In addition, the components of the steam jet cooling machine may also be present several times, for example as parallel or cascaded refrigeration circuits. Furthermore, the steam jet refrigeration machine may be a multi-stage steam jet refrigerator.

Also, it is generally possible to use an ionic liquid and a refrigerant which are miscible with each other. The condensate is then composed of a corresponding Mi ^¬ research of the ionic liquid and the refrigerant, whereby a separation of these components in the evaporator, at least partially is effected by that the refrigerant evaporated by the dependent terdruck, the ionic liquid is not. Thus, a mixed liquid can be provided in the evaporator with a high concentration of the ionic liquid. This mixed liquid with the high concentration of ionic liquid can then as propellant to the

Blasting nozzle 5 are transported. In particular, in this case, it is advantageous if a boiling point of the refrigerant ^{¬ is} lower than a boiling temperature of the propellant.

Claims

Steam blast chiller (1) for evaporating a cold ^¬ means (K) by negative pressure using a vapor jet of a propellant (F), wherein the Treibmit ^¬ tel is an ionic liquid. A jet steam refrigerator (1) according to claim 1, wherein the refrigerant (K) is a liquid having a lower boiling point than water. A steam jet refrigerator (1) according to claim 2, wherein said refrigerant (K) comprises alcohol. Steam-jet refrigeration machine (1) according to one of the preceding ^¬ claims, wherein the foaming agent (F) is heavier than the refrigerant (K). Steam-jet refrigeration machine (1) according to one of the preceding ^¬ claims, wherein that a boiling point of Käl ^¬ temittels (K) is lower than a boiling temperature of the foaming agent (F). Steam-jet refrigeration machine (1) according to one of the preceding ^¬ claims, wherein the foaming agent (F) and the refrigerant ^¬ medium (K) are not miscible. Steam-jet refrigeration machine (1) according to one of the previous ^¬ claims, wherein the foaming agent (F) a kationi ^¬ specific liquid (F), in particular tetrafluoroborates, trifluoroacetates, triflates, hexafluorophosphates, nate phosphinothricin and / or tosylates, and / or derivatives thereof comprising. Steam-jet refrigeration machine (1) according to one of the preceding ^¬ claims, wherein the foaming agent (F) is an anionic liquid (F), in particular imidazolium, pyridinium, pyrrolidinium, guanidinium, uronium, thiouronium, pipe- Ridinium, morpholinium, ammonium and / or phosphonium and / or derivatives thereof. Steam-jet refrigeration machine (1) according to one of the previous ^¬ the claims, at least comprising  a jet nozzle (5) with a blowing agent connection (4), a suction connection (7) and a mixed flow outlet, a condenser (9) connected to the mixed flow ^outlet (12) of the jet nozzle (5) and - One connected to the condenser (9) evaporator (3), wherein the evaporator (3) has a blowing agent outlet (13) and a refrigerant outlet (8) on ^¬ and - wherein the Treibmittelauslass (13) via a För ^¬ dereinheit (2) with the blowing agent connection (4) of the jet nozzle (5) is fluidically connected and the refrigerant ^¬ middleauslass (8) with the suction port (7) of the  Blasting nozzle (5) is fluidly connected. Steam blast chiller (1) according to claim 9, wherein the evaporator (3) is designed as a heat exchanger. A steam jet refrigerator (1) according to claim 10, wherein the blowing agent (F) contained in the evaporator (3) is usable as a heat exchange medium. A method of operating a steam jet refrigerating machine (1) using a refrigerant (K) and a foaming agent (F), wherein the blowing agent (F) is a ioni ^¬ specific liquid.