DE2744618A1 - HEATING AND / OR COOLING ARRANGEMENT - Google Patents

Description

COMPAGNIE POUR L ¹ ETUDE ET LA REALIZATION DE COMBUSTIBLES ATOMIQUES (CERCA), Paris, France

Heating and / or cooling arrangement

The invention relates to an arrangement for heating and / or cooling a temperature-carrying fluid, which is intended, for example, for heating and / or air-conditioning rooms, for generating hot sanitary water or for agricultural and industrial applications such as drying.

In the various heating systems currently in use, there is sometimes an irregular or discontinuous source of heat and often a use which in turn is irregular and discontinuous depending on climatic conditions or the needs of a user. This often means that a store of the energy obtained must be provided, the store generally being kept at a temperature close to the use or consumption temperature. Taking into account the difference between the consumption temperature and the

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Ambient temperature, even with suitably insulated storage tanks, there are thermal losses that can amount to up to 10 to 20 % of the energy consumption during a period of 24 hours. The various storage methods generally use the excess heat of various liquids or solids. In this case, the storage of a considerable amount of heat is not possible because of the implementation price for a considerable volume in the case of a liquid such as water or a considerable mass in the case of a solid.

In addition, heating and / or air conditioning equipment has already been set up thought that use the technology of the heat pump. The amount of heat in this case can be either that The water of a river, a lake or a sea or the external atmospheric environment (see FR-PS 1 448 300). Such systems often lead to the use of unusual and therefore expensive materials with a complicated one and sensitive control or regulation and an uncertain efficiency. In addition, there is certain climatic conditions the risk of the arrangement icing up, which can hardly be completely removed.

It should therefore be noted with regard to the known system that if the difference between the temperature of the external environment and the temperature of the room to be air-conditioned increases, the efficiency of the arrangement drops rapidly and that additional heating must be provided. In addition, the storage takes place through an extensive or bulky arrangement of great thermal inertia (hollow volume filled with water, porous crucibles), which can only ensure storage for a short period with considerable thermal losses.

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^It is therefore the object of the invention, on the one hand, to avoid thermal losses by storing at low temperature, generally below ambient temperature, and thus to enable storage for a long period of time, and, on the other hand, to use the storage container to store the heat quantities of the latent heat of fusion of a substance to make it more compact.

It should be possible to install a heat pump in the heating and / or cooling arrangement that is constantly close to the working under optimal conditions with excellent efficiency. It should also be possible to use an irregular and to use discontinuous heat sources, such as solar energy, without and with auxiliary heating significantly better efficiency compared to existing arrangements.

The invention enables the use of a single arrangement both for heating and for cooling, for example, for heating a room in winter and air conditioning in summer.

According to the invention, the heating and / or cooling arrangement contains

a primary circuit for heat exchange between the outside environment and a primary heat exchange fluid,

a storage container for the amount of heat, which is kept at a practically constant temperature, preferably between 5 ⁰ C and 20 ⁰ C, as a result of the latent heat of fusion of a heat-storing substance, the container having a heat exchange system for exchanging heat between the heat-storing body and the heat-dissipating primary heat exchanger fluid,

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a consumer circuit of a second heat dissipating unit Fluids,

a heat pump, which in a known manner by a compressor, a condenser, a pressure reducer and an evaporator is formed forming a closed circuit with an easily liquefiable working fluid is filled, the evaporator and the condenser in thermal communication with the primary circuit, the storage tank and / or the consumer can be critical.

The heat storage material preferably has a melting temperature in the order of the mean ambient temperature between 5 ⁰ C and 20 ° C and a high latent heat of fusion. One could initially think of water with a high latent heat of fusion (79 kcal / kg), but when stored at a temperature of the order of 0 ^° C. it is very difficult to freeze certain parts of the arrangement based on atmospheric moisture avoid, which is why it is advantageous to choose a substance that has a higher melting temperature above 5 ⁰ C. On the other hand, if the melting temperature is very high, the thermal losses increase, which is why it is expedient to limit ^{them to 20 ° C.} Further, it is desirable to avoid the use of hydrated salts, such as CaCl _2, Na ₂ CO ,, Na ^ SO _3, ^Na 2 ^S 2 ° V ^whose latent heat of fusion is high, however, the melting temperature exceeds 30 ⁰ C. It is also preferable to use an unhydrated body or cloth. The melting of hydrogenated substances brings with it the risk that it will take place by exceeding intermediate hydrate formation stages, which can be changed depending on the heat kinetics, ie the heat flows received and used, which can interfere with the operation of the arrangement.

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According to the invention, the heat-storing substance used advantageously comes from a group that is formed by acetic acid, 1,4-dioxane, formic acid, acrylic acid and glycerine.

The properties of these substances are shown in Table I.

Panel I.

Melted 12.3 latent enamel specific latent speci temperature 18.1 warmth Dimensions fish warmth ⁰ C kcal / kg g / cnr kcal / 1 acetic acid 16.7 45.9 1.049 48.2 1,4-dioxane 11.0 34.8 1.034 36.0 Formic acid 8.2 66.0 1.220 80.6 Acrylic acid 37.0 1.051 38.6 glycerin 47.9 1.262 60.4

It can be stated that the most interesting substance is formic acid, since on the one hand it is sufficiently deep Melting temperature, so that the heat pump works under optimal conditions, and because this on the other hand a has a high heat of fusion and exceeds that of the equivalent volume of water. After all, it's one popular fabric at a reasonable price.

Because the storage is close to the melting temperature of the heat-storing Substance takes place, the thermal losses in the arrangement are for both the storage tank as well the pipelines practically zero, eliminating the suppression

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any thermal insulation is achievable. The work or effect of the heat pump can under optimal conditions take place because their evaporator or possibly their condenser in the case of cooling is constantly at a temperature close to the melting temperature of the heat-storing material is maintained. Under these conditions, the one to work is the The energy required by the heat pump is always well below the energy required by reducing thermal losses and the improvement in the overall efficiency of the arrangement is saved.

The heat exchange system of the storage container between the heat-storing substance and the primary fluid is advantageous formed by a stacking of elementary volumes of heat-storing substances, which in a deformable Sheath low thermal inertia are insulated, with a certain void volume between them is released for the circulation of the primary heat transfer fluids.

In this way, there is a considerable surface / volume ratio and constant contact between the heat-storing substance and the primary fluid as a result of the deformability of the envelopes, which enables the changes in volume to follow the changes in state and thus ensures a good heat exchange. The stacking can be formed, for example, by small plastic balls that enclose the heat-storing substance. Other heat exchange systems are possible _/ for example a plate heat exchanger, one circuit of which is closed on a static charge of the heat-storing substance.

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The arrangement according to the invention is particularly important when solar energy is used. Storage at low temperatures enables the working temperature of the sensors to be reduced and thus a significant increase in their efficiency. This allows much simpler and less costly transducers to be built than conventional circuits using solar energy. In particular, it can be advantageous in this case to use sensors whose solar radiation absorbing and heat transfer fluid with the primary heat transfer fluid pane is in direct contact with the outside atmosphere _/ without a glass pane or the like in between. to have to arrange. As a result, a thermal efficiency is obtained that is greater than the optical efficiency, for every outside temperature that is higher than the storage temperature.

Finally, the use of a heat pump assigned to solar energy is important because it is a Source of inexhaustible, well distributed and storable Energy acts, while water acts a cold, poorly distributed one and is often exhaustive source and while outside air is used as a cold source at low temperatures causes major problems (e.g. icing). After all, if the solar energy should not be enough, that Heat pump use outside air as a heat source, for example in mild and overcast weather, while in cold and dry weather which can use solar energy, these modes of operation using the same transducers what consequently does not complicate the arrangement.

The invention therefore provides an arrangement for heating and / or cooling a heat-transferring fluid that is practical is free from thermal losses. This arrangement contains

a) a primary heat exchange circuit between the external

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Environment and a primary heat transfer fluid,

b) a heat storage tank that is between 5 and 20 ° C is held, as a result of the latent heat of fusion of a heat-storing substance, the container having a heat exchange system between the primary fluid and the heat-storing substance,

c) a group of users or consumers,

d) a heat pump, its evaporator and its condenser in thermal connection with the primary circuit, the Storage container and / or the useful circle can be brought.

The invention is particularly useful for heating and air conditioning of rooms, for the production of sanitary water and for industrial drying based on solar energy applicable.

The invention is illustrated with reference to the drawing Exemplary embodiments explained in more detail. Show it:

1 schematically shows generally an arrangement for heating;

2 schematically shows the circuits of a mixed arrangement for heating and air conditioning, which is provided with a distribution system is provided;

Fig. J5 to 7 each different operating circuits, the the distributor allows depending on temperature parameters for each heating arrangement (winter);

8, 9 each operating circuits for day and night with summer air conditioning.

The heating arrangement shown schematically in Fig. 1 has a sensor circuit for solar energy, the / at least one sensor 1, in which the solar flow is absorbed by an absorbing surface, which transfers the amount of heat to a heat-transferring fluid by means of a

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suitable exchanger system. The primary heat transfer fluid, which can be provided with an anti-gel, for example, is via a line 2 with a Storage container 3 is connected and returns to the transducer 1 via a line 4. Kine pump 5 provides the circulation of the primary heat transfer fluid in the circle. Among other things, the temperature in the storage tank 3 is sufficient is low, the primary sensor circuit always remains at a moderate temperature, which is why the Losses due to radiation or convection remain low. It is therefore not necessary to provide double glazing and even sensors without glazing can be used if the operating temperature is on a sufficiently low level is kept, whereby a reduction in the manufacturing price of the transducers is possible.

The storage container 3 is formed by a vertical cylindrical balloon which contains a stack of small balls made of plastic, for example made of polypropylene, which are filled with formic acid. With spheres with an outside diameter of 20 mm and a thickness of 1 mm and a compact hexagonal storage, the result is a vacuum proportion of 25.6 %.

Taking into account the wall thickness of the spheres, the storage errors due to wall effects and the possible presence of heat exchangers, the result is a degree of filling of formic acid in the order of magnitude of 64 %. This degree of filling can also be increased by using balls of different diameters.

The balloon or the storage container 3 has an upper one Pipe branch for the entry of line 2 and one

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lower pipe branch for the return to transducer 1 via line 4. Finally, Rr contains one
Heat exchanger that makes the evaporator a heat pump.

The deformability of the plastic balls makes it possible to change volume as a result of changes in state
absorbing and storing the balls makes it possible to obtain a high surface / volume ratio, which allows a good heat exchange between the primary heat transfer fluid, the formic acid and the working fluid of the
Allows heat pump, these elements are separated.

The storage container 3 for balls can optionally be replaced by a container which contains a plate heat exchanger whose one circuit is closed on a static one
Charge of formic acid, with another circuit ensuring the circulation of the primary heat transfer fluid and with a third circuit connected to the evaporator of the heat pump.

The storage container 3 must take into account his Temperature cannot be thermally insulated and can be a container buried in a dry place.

The heat pump circuit contains a compressor 6, a condenser 7, in the usual way
Pressure reducing valve 8 and an evaporator 9, the overall arrangement forming a closed circuit which is filled with an easily liquefiable working fluid. The evaporator 9, which is formed, for example, by a snake, is either located in the storage container 3 filled with formic acid or outside it, but in a thermal state
Connection with it, for example, via the primary heat transfer fluid ₇ and is therefore kept at a constant temperature of the order of 8 ⁰ C, whereby the structure

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the heat pump can be simplified and the risk of icing of the evaporator 9 is eliminated. The capacitor 7 is located in the useful or consumer circuit and provides heat exchange with the heat transfer fluid this Circle safe. The heat transfer fluid can be air, in the case of heating with pulsating air or water, in the case of water central heating or in the production of hot water for sanitary purposes. The heating of rooms can be ensured in the usual way by radiators, convectors or heated floors The latter solution is particularly important because, if carried out correctly, it only requires a very moderate temperature of the heating water.

The arrangement is of course with the usual accessories for filling, cleaning and emptying, which are commonly used in conventional arrangements will.

The arrangement can advantageously be completed by a distributor device, an embodiment of which is shown schematically in FIG. These Manifold arrangement is formed by a group of coupled valves and a control system, the the optimal distribution between the primary heat transfer fluid, of use and storage, depending on the temperature differences between the different limbs.

The operation of this device is referenced explained on separate circles, which are shown schematically in Fig. 3 to 9, each of an operating phase of Arrangement.

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If the outlet temperature of the transducers 1 is not sufficient, i. i.e. if they are in the illustrated case under 8 C, which occurs in cold and overcast weather, all of the primary heat transfer fluid is via one Bypass fed back to the transducer 1, like that in Fig. 3 is shown. During this time or this weather, the consumption requirement is taken from the storage container 3 by means of the heat pump.

When the outlet temperature of the sensor 1 rises and (for example) ^{exceeds 8 °} C. (see FIG. 4), the primary heat transfer fluid is progressively or rising by means of a controllable valve 10 for consumption and the withdrawal at the storage container is correspondingly reduced.

When the energy taken off becomes sufficient, the Removal at the storage container 3 is finally set completely, as shown in FIG.

The heat quantity is transferred directly from the sensor circuit to the consumption via the heat pump.

As soon as the absorbed energy is greater than necessary, the amounts of heat are fed to the storage tank 3 (Fig. 6) and a thermostat located in the consumer rooms triggers the heat pump to stop.

Instead of the parallel mode of action just described, a serial mode of action can also be achieved, such as which is shown in FIG. 7, according to which the primary fluid coming from the sensor always flows through the storage container 3.

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which cannot be taken out of service. There, too, it is possible to stop the compressor 6 of the heat pump to be achieved by means of an ambient thermostat 11.

In all cases in which the primary WärmeUbertragungsfluid flows through the storage container 3 is removed, the outlet tempera has hardly any door of the pickup 1 from (for example) 8 ⁰ C, whereby the pickup 1 excellent efficiency.

The Hei ζ arrangement of the type described can also be used for summer air conditioning, namely in the following way.

The heat transfer fluid is used in the consumer or utility circuit directly circulated (see. Fig. 8), which is located in the storage container 3, which thereby as "constrict cold" source is used without using a heat pump, whereby the primary circuit is no longer connected to the storage tank 3 connected is. To remove the heat from the storage tank 3 it is sufficient to let the heat pump between the storage tank j5 and the primary circuit work at night, as shown in FIG. The primary circuit, which is now connected to the condenser 7 of the heat pump, releases the heat accumulated during the day into the nocturnal outside atmosphere.

Such a catfish is independent of the type of Primary circuit possible.

If, as in the illustrated exemplary embodiment, the primary circuit is a pickup circuit for solar energy, delivering or scattering of amounts of heat may be in the atmosphere or

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Environment take place via a transducer without glazing, the absorbent surface is designed so that it can receive solar flux during the day and can give off quantities of heat at night.

In this way, the arrangement according to the invention enables a high degree of adaptability in the selection of an energy source in addition to solar energy in such a way that certain climatic conditions or consumption conditions can be exploited. ] s is in fact possible, the most economical source to use, even if the temperature level is quite low. However, these low temperature energy sources are almost always the most economical and they are not widely used because their thermal flux is low. However, this disadvantage does not exist in the arrangement according to the invention, since this flow intervenes or is used before storage. The advantages of the invention are finally explained using an example which shows the thermal balance of an arrangement according to the invention.

Example:

The daily hot water consumption of a family of four can be ensured by a hot water balloon or storage tank that ^{stores 300 1 at 60 0} C, which is the average consumption.

Starting from cold water at 12 ^° C., this means an energy consumption of 17 kWh or, taking into account thermal losses, around 20 kWh.

ka rin

.. The same result / with an arrangement according to the invention. after 'a solar energy absorber, a

Storage balloon of 250 1 with 250 χ 0.64 = l60 1 formic acid

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and a storage capacity of around 15 kWh can be achieved.

To limit the output of the heat pump, which is necessary to ensure a constant throughput, it is advantageous to provide a small hot water balloon of 100 1 at 45 ⁰ C, which makes it possible to ensure the maximum one-time water requirement, which corresponds to a full bath, for example. Assuming that this balloon reaches its equilibrium temperature in 1 hour and assuming a heat pump coefficient of performance of 4.5, a compressor with an output of 1.25 kW is necessary and the same service as above is provided with an energy consumption of the compressor of 4 , 5 kWh received. By adding the energy consumed by the circulator, a total energy consumption of 5 kWh is obtained. Furthermore . the thermal losses are much lower, since they can only occur on a small balloon of 100 1 at 45 ⁰ C instead of a large balloon of 300 1 at 60 ° C.

Assuming that these losses are reduced to 1 kWh, the energy consumption is therefore 1/3 less than that required for electrical water heating.

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Claims (11)

Expectations (l J arrangement for heating and / or cooling a heat transfer fluid, in particular an arrangement for heating and / or air conditioning rooms, for generating Sanitary water, for drying in agriculture or industry, etc., marked by a primary circuit for heat exchange of heat quantities between the outside environment and a primary heat transfer fluid, a storage tank (3) for storing amounts of heat, which is kept at a practically constant temperature, which is preferably between 5 C and 20 C, due to the latent heat of fusion of a heat-storing substance, the storage container (3) having a heat exchanger system between the heat-storing substance and the primary heat transfer fluid owns, a useful circuit of a secondary heat transfer fluid, and a heat pump that is formed in known per se is through a compressor (6), a condenser (7), a pressure reducer (8) and an evaporator (9), which are a closed Form a circle filled with an easily liquefiable working fluid, the evaporator (9) and the condenser (7) in thermal connection with the primary circuit, the storage container (3) and / or the utility circuit are bringable. 2. Arrangement according to claim 1, characterized in that the heat-retaining substance comes from the group that contains Acetic acid, formic acid, 1,4-dioxane, acrylic acid and glycerine. 8098U / 09B2 OAlGINAL INSPECTED -υ? -1 3. Arrangement according to claim 1 or 2, characterized in / let the storage container (3) with a stack formed by ^ elementary volume of heat-storing materials is insulated in a deformable shell of low thermal inertia, being between them a certain empty volume remains for the circulation of the primary heat transfer fluid. 4. Arrangement according to claim 3 * characterized in that the storage container (3) with a stack of small plastic balls that surround the heat-storing substance, is filled. 5. Arrangement according to claim 1 or 2, characterized in that that the storage container (3) contains a plate heat exchanger, one circuit of which is closed over one static charge of the heat-storing material. 6. Arrangement according to one of claims 1 to 5, characterized in that the primary circuit is a sensor circuit for Solar energy is that has at least one solar radiation absorbing disc or plate that absorbs the heat exchanges with the primary heat transfer fluid. 7. Arrangement according to claim 6, characterized in that the absorbent disc is in direct contact with the Outdoor environment is. 8. Arrangement according to one of claims 1 to 7, characterized by a distribution device, which by a group of Coupled valves and a regulating or control system is formed, which is dependent on the temperature ranges between 8098U / 0952 274A618 the various members an optimal distribution of the primary heat transfer fluid between the primary circuit, the storage tank (3) and the useful circuit ensures. 9. Arrangement according to one of claims 1 to 8, characterized characterized in that for heating the evaporator (9) and the condenser (7) of the heat pump are each in thermal connection with the storage tank (3) or the utility circuit. 10. Arrangement according to one of claims 1 to 8, characterized in that for cooling during the day Heat transfer fluid from the storage tank (3) is fed directly to the utility circuit for cooling, the heat pump is turned off and the primary circuit is no longer connected to the storage container (3), and that at night the heat pump works between the storage tank (3) and the primary circuit, with its condenser (7) is thermally connected to the primary circuit in order to dissipate the amount of heat into the outside environment. 11. The arrangement according to claim 10, characterized in that the absorbing surface of the solar energy sensor (1) is designed so that it can release amounts of heat into the atmosphere during the night. 8098U / 0952