DE3127096A1 - Latent heat store - Google Patents

Abstract

The invention relates to a latent heat store having a filling which consists partly of a liquid heat transfer agent and storage agent, e.g. water - if necessary with the addition of an anti-freeze agent - and partly of a latent storage compound, which given a change in temperature approximately in the range between 30 and 70 DEG C experiences a conversion from the solid to the liquid state or vice versa and in the process absorbs or re-releases a relatively large quantity of heat. By subdividing the store into at least two subchambers, of which at least one subchamber contains a transfer and storage agent that continually remains liquid, and only further subchambers additionally contain the latent storage compound, which is preferably accommodated in hose-shaped or tubular containers, it has been achieved that it is possible, without too strongly heating the transfer agent, for the container part that is filled only with liquid transfer and storage agent both to have extracted from it a relatively large quantity of heated service water required only in the short term, and to have absorbed from it a relatively large heat quantity supplied from a heat source, the further storage parts with the latent storage compound accommodated therein serving the purpose of longer-term heat storage. The conversion rate of the storage compound between the solid and liquid state and vice versa has been substantially enhanced by a particularly advantageous development of the latent heat store according to the invention, that is to say adding to the latent storage compound components a thermally effectively conducting metal that has as large a surface as possible in relation to its volume.

Description

Depositor: Anton Reißnniller,.? 3a3 "« c> rir: j | «n-JVberiha UM ⁸ TO ^" ^W "

Dipl. Ing.Franz ViJJ ° ii3g ^ r _ρ ° _ο0 ^ 3 | ΐ Latent heat storage

The strongly fluctuating energy supply over time, especially from the constantly self-renewing natural energy sources in the form of solar and wind energy, only makes economic sense to use them to gain usable heat, especially for hot water supply and for heating buildings, if a possibility to store the excess heat from the times of high energy supply for the times of too little or no supply is available. Therefore, numerous suggestions have already been made for the most diverse systems of heat storage? but so far have not yet led to a fully satisfactory solution to this problem in practice. In view of the space required for the V.irme storage, a favorable way is to use so-called. ⁺ he latent heat storage. These work -as for example in the DOS-Wr. 29 34-321 proposed- with a container filling ,, which partly consists of a liquid transfer medium ,,: ^r , .B. Water optionally with the addition of an antifreeze agent and on the other hand consists of a latent storage mass, which undergoes a conversion from the solid to the liquid state of aggregation or vice versa ^{when the temperature changes between about 30 and 70 0 C and absorbs a relatively large amount of heat and} relinquishes »This theoretical advantage of such latent heat accumulators using above all Glauber's salt (NapSO, .10 H ^ O) with certain admixtures has not yet been able to be used satisfactorily in practice because the accumulator mass - besides its Tendency • to strong supercooling in the liquid state - because of their low thermal conductivity, too long periods of time are required for the conversion in the solid state. As a result, the temperature drops rapidly when a large amount of heated service water is withdrawn from such a storage tank, thus severely reducing the availability of the stored heat. on the other hand

will strong heat input into the storage from an energy source the liquid transfer medium is heated to an undesirably high level, which is the case for reasons of cost and safety

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advantageous use of pressureless - preferably open at the top - storage containers to a strong evaporation of the Transmission fluid leads "

The object of the invention is to provide a latent heat storage device To create the type described above, in which the disadvantages associated with these hitherto have been overcome. This task has essentially been achieved by an embodiment according to the characterizing part of claim 1. Through the subdivision of the heat accumulator in at least two sub-spaces of which one sub-space only contains the permanently liquid heat transfer and Storage Agent -z "B. Water and only the other subspaces In addition, the preferably tubular or tubular containers with latent storage material have been achieved: that from the container part with only liquid heat transfer medium both a short-term required larger amount of heated domestic water is taken from sbl as well as one from one Greater amount of heat supplied to the heat source without excessive heating of the transmission medium can be added, while the other for longer-term heat storage -depending on the size of the storage tank- can be charged or discharged over days or weeks. By the special advantageous further embodiment of the latent heat storage device according to the invention The rate of conversion of the latent storage mass is also in accordance with the characterizing part of claim 2 between the solid and liquid aggregate state has been increased significantly. Applying a top layer of a Material with a lower specific weight and a higher melting point than the main storage mass on the storage filling -preferably from a mixture of paraffin and petroleum jelly- prevents even when designing the memory under Use of open-topped and therefore easily accessible containers with security of any evaporation of the heat transfer liquid

Further advantageous features and properties of the invention Latent heat storage results from the associated Claims and the following description of an exemplary embodiment on the basis of the drawing with two figures. from these show:

Fig. 1 shows a latent heat storage device according to the invention in longitudinal section, but still without the latent storage mass and

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Fig, 2 shows a cross section along the line I I = I Γ through don the same storage facility with the Laf ^ nt storage masses marked in it "

The embodiment of a latent heat storage device according to the invention illustrated in the drawing consists of three individual vessels in the form of open-topped drums 1p2,3 made of corrosion-resistant metal, plastic or the like, all of which have a liquid heat transfer and storage medium 4-, e.g., water are filled. Of these, the container 1 is only filled with the permanently liquid heat transfer agent, while the other containers 2 and 3 also have a latent heat storage mass 7, e.g. Glauber's salt, housed in vertically arranged tubular or tubular containers 5ρ6, e.g. Glauber's salt with suitable as nuclei serving additives contain or at a specific temperature of, for example, 32-33 ⁰ C from solid to liquid state _o vice versa passes while a much greater amount of heat receiving or "re-emits as water at a same temperature change. The containers for the latent storage mass 7 can advantageously consist of relatively thin-walled and small individual cross-sections of plastic tubes 5 or of tubes 6 of a highly thermally conductive metal, for example “copper”. To further improve the heat exchange between the transfer liquid 4 and the latent heat = storage = mass 7, the latter are purposefully components of a highly thermally conductive metal with the largest possible surface area in relation to their volume, preferably in the form of copper = ,, Brass or similar Shavings mixed in. To introduce the heat into the storage tank according to the invention and to remove it again in the form of heated service water or for heating purposes, two separate countercurrent systems of serially connected pipe coils 9 _P 9 ' _P 9 "and 10, 10 _{are located in its sub-spaces 1 p 2" 3} ' , 10 " arranged. The coils for heat introduction 9 _Ρ 9'ρ9 "are each in the lower part of the container 1 _P 2 _P 3 and are flowed through by a liquid transfer medium coming from any heat source in the order 1 _P 2 _P 3 _{10, 10 ', 10 "are flowed through P} starting at the last partial storage 3 in the reverse order 3» 2.1, so that the partial storage 1 containing only a permanently liquid heat transfer medium is the strongest

■ • rw ^; innL and d.iduroh ana in the T <"> Ll-fip ^ iohorn 3 and 2 already before ,; _t - w ^; i t-fflf ι · Mrrtui'hwaiirior mil", dor hüchtmöglj the temperature en tnommeri. By applying a cover layer 8 made of a mixture of paraffin and vaseline to the container fillings, every evaporation of moisture from the sub-spaces that are open at the top and are therefore easily accessible for the installation of the heat exchanger coils and the containers 5, 6 for the latent storage mass has been achieved to prevent., which is of great importance for the practical operation of, for example, heat accumulators housed in the basement of a building. The cover layer 8, made of a material that changes its state of aggregation only at a higher temperature, but always has a certain elasticity, increases the capacitance once ^; if, f] ■ · .ι Γι p. "1 .i'hof'a" vorbncisort at the same time the thermal insulation, increased "lic Holm 1 ter-wioherhoi t in case of volume changes due to the temperature fluctuations and facilitates the accessibility to the storage Tanks e.g. during an overhaul process on the heat exchanger coils after a longer period of operation with an enlarged volume, that is to say with a larger cross-section and / or greater length than the pipe coils.

7321 Börtlingen, July 6th, 1981
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BATH ORIGINAL

Claims (1)

^ ff | .nmelder; Anton Reissmüller ,,? 3äÖeiföpraiagsh «JsT5®nlia.usen and ■ ^; , "- f * ■ ·. Dipl.Ing. Franz Vili'ing'er _p ^ 32 ^ BörEliügen. f claims Latent heat storage with a filling "which is partly a liquid heat transfer", and storage means, preferably in the form of water, optionally with the addition of an anti-freeze and, on the other hand, a late storage mass b.estehtj which is at temperature change, .Approximately between 30 and 70- ° ö conversion from the solid to the liquid aggregate state, and vice versa ■ erfährtp 'characterized in that ρ is Speieher into at least two chambers (1,2,3) is divided ^ “of which at least one ... sub-space (1) only remains continuously fluid via the" carrying and storage "means (4) and the further sub-spaces (2,3) in addition the latent storage mass (7), which is preferably accommodated in hose or tubular / γ containers (5,6) ;, contain" 2. Latent heat storage device according to claim 1 _P characterized “. that there © latent storage mass , Components of a highly thermally conductive metal with as much as possible large surface in relation to its volume z = B "in form ,, "of copper, brass, Opdergl» sheet metal chips, 3ο latent heat storage indbesondate according to claim 1 / dad urchge ■ k β η η ζ θ i without t " _ρ that the storage filling with a cover layer (S) made of a material with a lower specific weight and a higher melting point than the main - Storage Massa is provided » U ₀ La t en t »Was never * memory! according to claim 3p thereby \ geke η η a 'eic h. n ■■ & t "that the top layer (8) consists of a mixture of paraffin and vaseline ·" 5 »Latent heat exchangers ^ Spicher iaach claim Ί or the following ^ d a d u r. c h 'geke η γι ζ e i α h ne t _p that this a ^- us a battery of Einzelftfhältern preferably in Ferm of ¹ open-topped barrels od @ rg ^ _lO is the _p, voiiaugsweise with existing helical • f örmigen from Kupier countercurrently . . '; (■ BAD ORIGINAL separate pipe coils connected in series (9 '' 9 '' 9 "f. or 10, 10 ', 1O ¹¹ ) for the passage of a transfer liquid heated by any heat source in the lower tail _{t of} the container or for the removal of'^; wärrateia water provided in the upper part of the container, i "■; 6. Latent heat storage device according to claim 5, because; by , <;, characterized,. that the removal of orwnrmtem water passage into the pipe coil (.10) in'.dem only · _\: a liquid filled part Wärraeübertragungsmitt.sl memory, ·. (1) a larger pipe cross-section and / ßder a larger: .. · " Length than the pipe coils upstream of it · (10 ", 10 *)" "· -; ' in the other container parts. > · 7321 Börtlingen, July 6th, 1981
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