KR20140146623A - Method for pooling heat energy, and loop system for heat exchange between industrial and commercial sites - Google Patents

Abstract

The present invention relates to a system for enabling heat exchange between a plurality of industrial sites and commercial sites using a loop in which heat transfer fluids are circulated, each of said sites being associated with a producer and / . The present invention also relates to a method for pooling thermal energy at a local scale by connecting at least one site consuming thermal energy to at least one site generating heat energy and using a loop in which the heat transfer fluid circulates.

Description

METHOD FOR POOLING HEAT ENERGY, AND LOOP SYSTEM FOR HEAT EXCHANGE BETWEEN INDUSTRIAL AND COMMERCIAL SITES BACKGROUND OF THE INVENTION 1. Field of the Invention [

The present disclosure relates to the technical field of heat exchange and heat distribution systems.

The present invention relates to a method of pooling heat energy (heat) on a district scale, wherein the heat exchange loop connects at least one heat energy consumer site to at least one heat energy producer site.

The present application also relates to a thermal pooling system that can be used to practice the method.

In a given area, for example a township, there are plants with problems often associated with the use of energy generated in the form of low thermal energy heat (usually heat carried by fluids at temperatures below 150 DEG C) There are residential, office or industrial sites with energy requirements in the form of low temperature heat (home or tertiary heating, drying operations, heating greenhouses, etc.).

Factories that do not use excess low-level heat energy heat of factories, such as refineries or nuclear power plants, are generally converted to:

Air coolers acting as exchangers intended to distribute heat to air between process fluids and air; These devices are generally provided with electric fans for forced circulation of air;

Cooling towers of the chimney type with natural and / or natural suction, water is sprayed thereon to assist cooling. Here again, this heat is lost to the atmosphere;

● and / or as cooling water systems (generally glycolized water), cooling water is obtained by exchanging heat with seawater, water, etc. in exchangers or by cooler units. Here again, this heat is lost around.

For some of these, residential, office or industrial sites that require low temperature heat are:

● They use combustion or electric means to generate the heat themselves. In these two cases, the fuels are consumed and CO ₂ emissions are produced;

And / or they bring steam from nearby industrial sites or from the city's heating system, and again they consume the fuels to produce the heat.

Thermal integration between factories and / or residential or office sites is rare because, when thermal integration is performed, the two parties are interdependent for each operation. An example of this type of energy integration is disclosed at http://innovagro.net/pdf/agro-industries.pdf for heating agricultural greenhouses.

Duties to supply, fines for power outages, and short-term, risk-related constraints in the default of one of the parties are generally a challenge to dissuade investors. As explained in the example above, the fact that it uses excess energy from neighboring stand-alone industrial sites does not exempt the beneficiary from investing in his own boiler to cover any defaults by nearby industrial sites.

Beginning with an industrial heating plant, existing systems consist of recovering and returning a high temperature fluid, typically water, and a user cooled fluid at a temperature of about 100 ° C. Such a device requires the system to have multiple branches, each of which has a temperature suitable for its processing. The use of the branches of the supply lines and the pipes (discharge pipe, return pipe) causes a large amount of thermal losses. These problems arise, for example, on the website for Compagnie Parisienne de Chauffage Urbain, http://www.cpcu.fr/La-chaleur-urbaine/FONCTIONNEMENT .

The present invention relates to a method of pulling heat on a local scale, wherein a heat exchange loop is used to connect at least one heat energy consumer site to at least one heat energy producer site, the heat exchange loop comprising a heat transfer fluid, Is adjusted such that the temperature differences at any point in the heat exchange loop are less than 20 DEG C and the consumer site or sites take the energy required at one point in the heat exchange loop by heat exchange and the producer site or sites are generated by heat exchange Thereby discharging excess energy.

Advantageously, the temperature of the heat exchange loop is kept constant using an additional heating unit.

In one embodiment, a column buffer type thermal buffer storage is used to store excess thermal energy in the heat exchange loop.

An organic Rankine cycle can be introduced into the heat exchange loop to use excess heat energy in the form of electricity.

Preferably, the heat transfer fluid is selected from water, water-soluble mixtures, alcohols, hydrocarbons or ionic liquids.

The heat transfer fluid may comprise particles of a phase change material.

The present disclosure also relates to a system for pooling heat on a local scale,

• At least one heat energy consumer site,

• At least one thermal energy producer site,

And a heat exchange loop connecting the heat energy consumer sites with the heat energy producer sites together and having a flow rate controlled heat transfer fluid and heat exchangers by a pump.

In the system of the present application, the heat exchange loop may comprise an additional heating unit.

Figure 1 shows a known prior art system; Beginning with the industrial heating unit C, the system is arranged in parallel with a user, for example B1, B2, ... Bn, providing a hot fluid 1, generally water, at a temperature of about 100 ° C And recovering the fluid (2) cooled by the building (s).
Figures 2 to 5 are non-limiting illustrations of the present application.
Figure 2 shows our system using a heat exchange loop between energy issuers (e.g., plants) and energy consumers (e.g., buildings).
Figure 3 shows an embodiment of the present invention using pooled column buffer stores.
4 shows an embodiment of the present invention wherein the system comprises an organic Rankine cycle.
Figure 5 shows an embodiment of the present invention wherein the heat transfer fluid or fluids of the chemical loop comprise a phase change material in the form of capsules.

More particularly, the system according to the present invention (FIG. 2) consists of locating a common loop of heat transfer fluid between a set of energy consumers and suppliers. By the heat exchangers located in the loop lines, consumers take the energy they need by heat exchange and, depending on the needs of the heat exchanger, the suppliers emit excess heat energy, which is produced by heat exchange.

By means of the pump P, the heat transfer fluid moves in a loop connecting energy consumers (buildings B1, B2, B3, Bn) and energy suppliers (plants U1, U2).

The flow rate of the heat transfer fluid can be such that at any point in the loop the temperature differences are small, preferably between 5 ° C and 20 ° C (for example, the maximum temperature difference can be 20 ° C, Lt; 0 > C).

The heat transfer fluid is any fluid that allows heat exchange in the various pieces of heat exchange equipment and is preferably selected from fluids in liquid state at relative pressures in the range of 1 to 20 bar so that the cost of the lines of the loop is too high It does not become high. Examples of heat transfer fluids that may be mentioned are water, water-soluble mixtures, alcohols or hydrocarbons, or actually ionic liquids.

Examples of consumers that may be mentioned are households or industrial buildings to be heated or factories that actually carry out industrial processes requiring heat, for example in the agro-alimentary industry, admit. Suppliers include factories that distribute heat lost to the atmosphere according to prior art.

For example, if the energy balance from the contributors to the loops (in this case the plants U1, U2) is insufficient, an additional, substantially reduced size compared to prior art industrial heating units, Using the heating system C, the temperature of the loop is advantageously maintained. This means that the total consumption of energy here is greatly reduced because the heat is pooled in the loop and the additional heating unit is dimensioned such that the temperature differences within the loop are gentle.

In one embodiment of the invention, the system (FIG. 3) is equipped with one or more pooled thermal buffer reservoirs (Q) referred to by manufacturers (e.g., German company H. M Keizkorper) . For example, the storage system can use sodium acetate. Storing the heat means that the temperature of the roof can be flat over time (eg, night / day or winter / summer), or the buildings can be heated by doing maintenance work at the heat supply plant.

In another embodiment of the present application, the system (FIG. 4) is provided with, for example, electrical energy, if necessary, for excess thermal energy (instead of sending heat energy to a chiller such as an air cooler) An organic Rankine cycle (ORC) can be used which can be used to convert the compound. This electrical energy can be advantageously used to operate the air conditioning.

According to the present application, one of the users may require a higher level of heat than the temperature of the high temperature loop (for example, at a temperature of 120 [deg.] C for industrial agricultural support cooking by a loop maintained at a temperature close to 70 [ : In this case, the user can install an additional heat pump that can be used to raise the temperature by consuming additional electricity.

In accordance with the present disclosure, the heat transfer fluid can include solid particles that can encapsulate a phase change material (e.g., sodium acetate) and cause it to increase the energy that can be recovered with small temperature changes. In fact, when a pure substance changes phase, the energy content (enthalpy) changes without changing the temperature. A well-known example is water, and water will go from solid to liquid at atmospheric pressure 0 DEG C, but in the case of the present invention, it will typically require a phase change at a temperature of 50 DEG C to 100 DEG C. Such a phase change material is preferably selected from the following compounds; Melting points are indicated in parentheses:

Sodium acetate trihydrate (58 占 폚), partially hydrated zinc chloride = (76 占 폚)

Some examples of ionic liquids having a melting point in the above range are as follows:

Butyl-3-methylimidazolium tosylate: mp = (67 < 0 > C)

1-ethyl-3-methylimidazolium hexafluorophosphate: mp = (59 DEG C)

1-butyl-1-methylpyrrolidinium hexafluorophosphate: mp = (85 DEG C)

Butyl-3-methylimidazolium chloride: mp = (73 < 0 > C)

1-ethyl-3-methylimidazolium chloride: mp = (77-79 < 0 > C)

Figure 5 shows lines for a chemical loop carrying transferred heat transfer fluid F containing the phase-change material (liquid phase (L); solid phase (S)). The envelope (E) for encapsulating the phase change material may be formed of a plastic such as polyethylene or polypropylene.

Claims (8)

A method for pooling heat on a district scale,
A heat exchange loop is used to connect at least one heat energy consumer site and at least one heat energy producer site, wherein the heat exchange loop comprises a heat transfer fluid, the flow rate of the scavenge heat transfer fluid being such that the temperature differences at any point in the heat exchange loop ≪ / RTI >
Wherein the consumer site or sites take the energy required at one point in the heat exchange loop by heat exchange and the producer sites or sites discharge the excess energy generated by heat exchange. The method according to claim 1,
Wherein the temperature of the heat exchange loop is held constant by an additional heating unit. 3. The method according to claim 1 or 2,
Wherein a thermal buffer type of thermal battery type is used to store excess thermal energy in the heat exchange loop. 4. The method according to any one of claims 1 to 3,
Introducing an organic Rankine cycle into the heat exchange loop to use excess heat energy in an electrical form. 5. The method according to any one of claims 1 to 4,
Wherein the heat transfer fluid is selected from water, water-soluble mixtures, alcohols, hydrocarbons or ionic liquids. 6. The method according to one of claims 1 to 5,
Wherein the heat transfer fluid comprises particles of phase change material. As a system for pooling heat on a local scale,
• At least one heat energy consumer site,
• At least one thermal energy producer site,
And a heat exchange loop connecting the heat energy consumer sites and the heat energy producer sites together and having a flow rate controlled heat transfer fluid and heat exchangers by a pump. 8. The method of claim 7,
Wherein the heat exchange loop comprises an additional heating unit.

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