JPH02101357A - Method of driving heat pump facility - Google Patents

Abstract

PURPOSE: To separate water easily from heat transfer liquid by employing a liquid unmixable with water as the heat transfer liquid. CONSTITUTION: Heat transfer liquid delivered from an evaporator 2 is cooled down to 11 deg.C, for example, by discharging heat to refrigerant introduced to a heat pump facility 1 in circulation cycle. The cooled heat transfer liquid is discharged to a built-in filler 7 and heated through direct contact with ambient air of +5 deg.C, for example. Condensates produced by the heat transfer liquid are entrained by the heat transfer liquid to a collecting container 9. Since the heat transfer liquid is unmixable with water, condensate being absorbed through a dropping process are separated perfectly and drained from the collecting container 9 at an appropriate time interval.

Description

DETAILED DESCRIPTION OF THE INVENTION The invention relates to heat pump installations in which the evaporator of a refrigerant circulation cycle is acted upon by a heat transfer liquid led into an open cycle, and this heat transfer liquid is itself heated by the surrounding air. This relates to a driving method.

When the ambient air is used as a waste heat source, the evaporator generally requires a large surface area and is therefore an expensive structure. The heat transfer coefficients, which differ by a considerable order of magnitude on the refrigerant side on the one hand, and on the other hand, must be compensated for by surfaces of different size. Moreover, when selecting the material, corrosion problems often have to be taken into account, independent of the refrigerant used, so that the evaporator additionally has to be made of very expensive materials.

In order to avoid the above-mentioned difficulties, a connecting element can be created between the waste heat source air on the one hand and the evaporator of the heat pump on the other hand by connecting an additional heat transfer circulation cycle with brine as heat transfer liquid in between. It has already been tried to make. Since the evaporator of the refrigerant circulation cycle is operated with brine as the heat transfer liquid, the evaporator can be constructed relatively small due to the fairly good heat transfer conditions.

On the other hand, for heat exchange between air and heat transfer liquid, the required additional heat exchanger can be constructed from cheap materials, for example plastic. This is because the corrosion problems required by the refrigerant are also eliminated and the circulation cycle of the heat transfer liquid is open and guided and no longer requires any pressure resistance. The heat exchange between the air and the heat transfer liquid can in this case take place, for example, in a conventional cooling tower, in which the heat transfer liquid is evenly distributed through the built-in packing and is gradually distributed into the packing. drop down. Air, on the other hand, is drawn through the built-in packing using a fan. Since the heat transfer liquid has been cooled after passing through the evaporator of the refrigerant circulation cycle, appropriate heating is achieved by contact with the suctioned air. The amount of heat absorbed from the surrounding air by the heat transfer liquid is therefore used again to operate the evaporator of the refrigerant circulation cycle.

Water has already been used as a heat transfer liquid, mixed with additives such as glycols, which lower the freezing point of the water. As a result, the heat pump drive is at a temperature of F degrees, which is the problem here.
This is possible at a certain outside temperature around 0°C.

Due to the direct heat exchange between the air and the heat transfer liquid originating from the evaporator of the refrigerant circulation cycle at a temperature below 0°C, the air experiences F rotations above its dew point and therefore The condensation process that has been used up to now is such that moisture condenses and is acted upon by the heat transfer liquid in the built-in packing, resulting in condensation, and the moisture is absorbed by the heat transfer liquid resulting from a mixture of glycol and water. There are drawbacks to hot liquids. Therefore, as the operating time increases, the heat transfer liquid is diluted by the absorbed coagulated water, and at the same time the amount of heat transfer liquid circulating increases,
Therefore, the exchange device for heat exchange between air and heat transfer liquid freezes under unfavorable climatic conditions. Control to maintain a constant mixture concentration is expensive, and continuous processing of each water-diluted heat transfer liquid is expensive.

The object of the invention is to create a drive method that eliminates the drawbacks mentioned at the beginning.

This problem is solved according to the invention by using a water-immiscible liquid as the heat transfer liquid. In particular, in embodiments of the present invention, it is preferable that the heat transfer liquid that is immiscible with water has a specific gravity clearly different from that of water. This has the advantage that the moisture in the air that condenses in the area of the exchanger arrangement is certainly removed by the heat transfer liquid, but is not absorbed by the heat transfer liquid. The water can then be easily separated from the heat transfer liquid. The sharp difference in specific gravity between the water and the heat transfer liquid makes it possible to separate the water and the heat transfer liquid without much expense. Since the heat transfer liquid and the water carried with it by condensation do not mix, it is also possible, for example, to direct the water directly to a drain if a separating device is suitably formed, which may for example be a simple removable basin. Various preparations must be made in order to achieve complete separation. In a particularly advantageous embodiment of the invention, oil is used as the heat transfer liquid.

In a further development of the invention, it is provided that the heat transfer liquid is conducted through a device for separating water before being subjected to the action of the evaporator. This avoids, on the one hand, that the condensed water absorbed in the heat exchange of the heat transfer liquid in the pumps necessary for driving the circulation cycle is emulsified in the heat transfer liquid, and subsequently in the evaporator of the refrigerant circulation cycle. The product is shipped for cooling at a temperature below O''CC, and icing can be avoided within this range.

Next, embodiments of the present invention will be described in detail based on the drawings.

A heat pump installation l of conventional construction is provided with an evaporator 2, which on the one hand is supplied with the refrigerant of the heat pump installation and on the other hand is acted upon by a heat transfer liquid.

Heat transfer liquid, such as heat transfer oil, is passed through conduit 4 to evaporator 2.
and is supplied through the nozzle 5 of the heat exchanger 6. The heat exchange device 6 is constructed in cooling tower fashion with an integrated packing 7 onto which a heat transfer liquid is injected via nozzles 5. Air is drawn upwards through the built-in packing 7 using a fan 8 so that it is in direct contact with the heat transfer liquid which flows down through the built-in packing 7 from top to bottom.

The heat transfer liquid is captured in a collection vessel 9 from which it is sucked out by a pump lO and compressed via a conduit 3 through an evaporator 2 of a heat pump installation l.

A water droplet separator 11 of conventional construction is provided below the nozzle 5, by means of which the drops of heat transfer liquid drawn together by the air flow are captured.

The heat transfer liquid exiting the evaporator 2 is cooled by releasing heat to the refrigerant led to the heat pump equipment 1 in a circulation cycle. In a suitable drive, it is cooled to a temperature of, for example, 11"C. The heat transfer liquid cooled to that extent is discharged into the built-in packing 7, so that the heat transfer liquid is cooled to a temperature of, for example, +5°C.
heated by direct contact with the surrounding air, which has a temperature of . In this case, the condensed water condensing on the heat transfer liquid is carried into the collecting vessel 9 together with the heat transfer liquid.

Since the heat transfer liquid is however immiscible with water, as is the case for example in heat transfer oil, ■ a complete separation of the condensed water absorbed through the precipitation process occurs, so that this condensed water is especially removed from the collecting vessel 9. It can be removed at appropriate time intervals.

[Brief explanation of the drawing]

The drawing shows a flowchart of the apparatus according to the invention. Reference numbers in the diagram■...Heat pump equipment 2...Evaporator, 3, 4...Conduit 5...
Nozzle, 8... Fan 6... Heat exchange device 7... Built-in filling 9... Collection container, 10... Pump 11...
・Water droplet separator

Claims (4)

[Claims] (1) In the driving method of heat pump equipment in which the evaporator of the refrigerant circulation cycle is subjected to the action of the heat transfer liquid introduced into the open cycle, and this heat transfer liquid itself is heated by the surrounding air, the heat transfer liquid is A method characterized in that a liquid that is immiscible with water is used. (2) The method according to claim 1, characterized in that the heat transfer liquid that is immiscible with water has a specific gravity distinctly different from that of water. (3) A method according to claim 1 or claim 2, characterized in that oil is used as the heat transfer liquid. 4. Process according to claim 1, characterized in that the heat transfer liquid is conducted through a device for separating water before being subjected to the action of the evaporator.