FR3130946A1 - System for producing domestic hot water and heating integrated into a low-temperature heating network - Google Patents

Abstract

System for producing domestic hot water and heating integrated into a low-temperature heating network The invention relates to a system for producing domestic hot water and heating comprising - a primary circuit (1) capable of receiving a heat transfer fluid comprising: a hot heat transfer fluid inlet (2) and a cold heat transfer fluid return (3 ), - a thermal fluid storage tank (4) stratified by temperature, - a secondary domestic hot water circuit (10), - a secondary heating circuit (20), - a loop circuit (30), - a domestic hot water heat exchanger (13),- a loop heat exchanger (31), - the primary circuit (1) comprises a heating heat exchanger (22),- the domestic hot water heat exchanger ( 13) and the heating heat exchanger (22) are arranged in parallel on the primary circuit (1), and - the looping heat exchanger (31) and the heating heat exchanger (22) are arranged in series on the primary circuit (1). Figure for abstract: Fig.1

Description

System for producing domestic hot water and heating integrated into a low-temperature heating network

The present invention relates to the field of systems for producing domestic hot water and heating. The present invention will find its application more particularly in an advantageously carbon-free and low-temperature heat network to propose an improved substation architecture.

STATE OF THE ART

An urban heating network is a set of installations that produce and distribute heat to several buildings for heating and/or domestic hot water.

A heating network includes a heat production unit and a primary distribution network of pipelines transporting heat and distributing it to substations, also called user delivery stations.

Forming a closed loop, the primary distribution network is made up of pipes in which the heat is transported by a heat transfer fluid from the heat production unit to the exchange substation. An outward circuit transports the hot heat transfer fluid from the production unit. A return circuit brings back the heat transfer fluid, which has been relieved of its calories at the level of the exchange substation. The fluid is then heated again by the heat production unit and then returned to the circuit.

The exchange substations, conventionally arranged at the foot of the buildings, conventionally comprise at least one heat exchanger which allows the transfer of heat between the primary distribution network and the distribution network of the building or building sub-group .

Heating networks are developing more and more and are beginning to establish themselves well with various heat sources, in particular from waste heat. Heating networks allow the supply of heat for heating and for domestic hot water.

One of the problems of heating networks concerns the rational management of energy, in particular by limiting power calls and controlling the return temperature of the heat transfer fluid. Indeed, a return temperature of the heat transfer fluid that is too high is detrimental to the efficiency of the heat production unit. A high return temperature also leads to high fluid flow rates (for the same power exchanged) and therefore to an increase in the electrical consumption of the circulation pumps and therefore to a reduction in the overall efficiency of the system. To this end, a known technical solution consists in using on the primary circuit a heat transfer fluid storage tank which is temperature stratified. Thus, this type of storage makes it possible to smooth the power calls by drawing heat from its upper part and it makes it possible to lower the network return temperature as much as possible by drawing cold stored in its lower part.

There is also provided in the systems of the state of the art a recirculation exchanger which is used to maintain the temperature of the domestic hot water at a target temperature for example of 60° C. when there is no drawing. domestic hot water.

For example, the system described in the document EP2375175 is known, which is a system for producing domestic hot water using a first heat exchanger for the production of domestic hot water, a second loop exchanger and a buffer storage which stores hot in the upper part when there is no draw-off and cold in the lower part when there are DHW draw-offs. This system does not allow operation on any type of network and in particular not on low-temperature networks.

There is therefore the need to propose a solution which is adaptable to any type of network and which is both easily implemented while being reliable.

The other objects, features and advantages of the present invention will become apparent from a review of the following description and the accompanying drawings. It is understood that other benefits may be incorporated.

SUMMARY

• un circuit primaire apte à recevoir un fluide caloporteur comprenant :
  • une arrivée de fluide caloporteur chaud et un retour de fluide caloporteur froid,
  • un ballon de stockage apte à stocker le fluide caloporteur stratifié en température et comprenant un piquage supérieur connecté fluidiquement à l'arrivée de fluide caloporteur chaud et un piquage inférieur connecté fluidiquement au retour de fluide caloporteur froid,
• un circuit secondaire d'eau chaude sanitaire comprenant une arrivée d'eau froide sanitaire et un point de tirage d'eau chaude sanitaire,
• un circuit secondaire de chauffage comprenant un module de chauffage,
• un circuit de bouclage,
• un échangeur thermique d'eau chaude sanitaire configuré pour assurer les échanges thermiques entre le circuit primaire et le circuit secondaire d'eau chaude sanitaire,
• un échangeur thermique de bouclage configuré pour assurer les échanges thermiques entre le circuit primaire et le circuit de bouclage, caractérisé en ce que:
• le circuit primaire comprend un échangeur thermique de chauffage configuré pour assurer les échanges thermiques entre le circuit primaire et le circuit de chauffage, et
• l'échangeur thermique d'eau chaude sanitaire et l'échangeur thermique de chauffage sont agencés en parallèle sur le circuit primaire, et
• l'échangeur thermique de bouclage et l'échangeur thermique de chauffage sont agencés en série sur le circuit primaire.

To achieve this objective, according to one embodiment, the invention provides a system for producing domestic hot water and heating comprising:

• a primary circuit capable of receiving a heat transfer fluid comprising:
  • a hot heat transfer fluid inlet and a cold heat transfer fluid return,
  • a storage tank capable of storing the stratified heat transfer fluid at temperature and comprising an upper tap fluidically connected to the hot heat transfer fluid inlet and a lower tap fluidically connected to the cold heat transfer fluid return,
• a secondary domestic hot water circuit comprising a domestic cold water inlet and a domestic hot water draw point,
• a secondary heating circuit comprising a heating module,
• a loop circuit,
• a domestic hot water heat exchanger configured to ensure heat exchange between the primary circuit and the secondary domestic hot water circuit,
• a looping heat exchanger configured to ensure the heat exchanges between the primary circuit and the looping circuit, characterized in that:
• the primary circuit comprises a heating heat exchanger configured to ensure the heat exchanges between the primary circuit and the heating circuit, and
• the domestic hot water heat exchanger and the heating heat exchanger are arranged in parallel on the primary circuit, and
• the circulation heat exchanger and the heating heat exchanger are arranged in series on the primary circuit.

The present invention makes it possible to limit the power demands on the network by the simultaneous use of a storage tank and a series connection of the loop circuit and the heating circuit. Thus, the thermal energy remaining at the output of the loop circuit is used in the heating circuit without the need to call on or by limiting the power call on the network. In addition, the series connection of the loop exchanger and the heating exchanger advantageously makes it possible to reduce the return temperature of the heat transfer fluid in the network, thus promoting the production of heat upstream of the network. This arrangement also makes it possible to reduce the flow rates of heat transfer fluid for the same power exchanged.

The system according to the invention also makes it possible, with the parallel connection of the domestic hot water heat exchanger and the heating exchanger, to have a low temperature at the outlet of the domestic hot water heat exchanger and therefore to have effective cold storage in the storage tank or a reduced network return heat transfer fluid temperature. In addition, the paralleling of the loop exchanger and the domestic hot water heat exchanger allows the system to operate at low temperatures.

The system according to the invention has the great advantage of being able to operate over a network temperature range preferably between 63 and 110°C.

Another aspect relates to a process for producing domestic hot water and/or heating by a system as described above comprising, in a winter configuration, the circulation of heat transfer fluid from the looping heat exchanger towards the inlet of the heating heat exchanger.

BRIEF DESCRIPTION OF FIGURES

The aims, objects, as well as the characteristics and advantages of the invention will emerge better from the detailed description of an embodiment of the latter which is illustrated by the following accompanying drawings in which:

There represents the architecture of a system for producing domestic hot water and heating according to a first embodiment of the invention

There represents the architecture of a system for producing domestic hot water and heating according to a second embodiment of the invention.

The drawings are given by way of examples and do not limit the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily scaled to practical applications.

Claims (16)

System for producing domestic hot water and heating comprising:

• a primary circuit (1) capable of receiving a heat transfer fluid comprising:
  • a hot heat transfer fluid inlet (2) and a cold heat transfer fluid return (3),
  • a storage tank (4) capable of storing the heat transfer fluid stratified at temperature and comprising an upper tapping (5) fluidically connected to the inlet of hot heat transfer fluid (2) and a lower tapping (6a, 6b) fluidically connected to the return cold heat transfer fluid (3),
• a secondary domestic hot water circuit (10) comprising a domestic cold water inlet (11) and a domestic hot water draw point (2),
• a secondary heating circuit (20) comprising a heating module (21),
• a loop circuit (30),
• a domestic hot water heat exchanger (13) configured to ensure heat exchange between the primary circuit (1) and the secondary domestic hot water circuit (10),
• a looping heat exchanger (31) configured to ensure the heat exchanges between the primary circuit (1) and the looping circuit (30),

Characterized in that:

• the primary circuit (1) comprises a heating heat exchanger (22) configured to ensure heat exchanges between the primary circuit (1) and the heating circuit (20), and
• the domestic hot water heat exchanger (13) and the heating heat exchanger (22) are arranged in parallel on the primary circuit (1), and
• the circulation heat exchanger (31) and the heating heat exchanger (22) are arranged in series on the primary circuit (1).

System according to the preceding claim, in which the looping heat exchanger (31) comprises a hot heat transfer fluid inlet (32) and a cooled heat transfer fluid outlet (33) fluidly connected to an inlet of the heating heat exchanger (23 ) . System according to any one of the preceding claims, in which the primary circuit (1) comprises a supply (102) of the heating heat exchanger (22) configured to fluidically connect the hot coolant inlet (2) and the inlet heat transfer fluid (23) from the heating heat exchanger (22). System according to any one of the preceding claims, in which the primary circuit (1) comprises a variable-speed pump (7) arranged upstream of the inlet of the hot heat transfer fluid (14) into the domestic hot water heat exchanger . System according to any one of the preceding claims, in which the lower tapping (6a, 6b) comprises two branches (6a, 6b) mounted in parallel configured to respectively ensure the circulation of heat transfer fluid from the cold heat transfer fluid return (3) to the storage tank (4) and from the storage tank (4) to the cold heat transfer fluid return (3). System according to any one of the preceding claims, in which the primary circuit (1) comprises an additional storage tank (40) comprising an upper tapping (50) fluidically connected to the hot heat transfer fluid inlet (2), a lower tapping (60) fluidically connected to the cold heat transfer fluid return (3) and an additional upper tapping (51) fluidically connected to the cooled heat transfer fluid outlet (33) of the loop heat exchanger. System according to any one of the preceding claims, in which the domestic hot water heat exchanger (13) and the circulation heat exchanger (31) are arranged in parallel on the primary circuit (1). System according to any one of the preceding claims, in which the loop heat exchanger (31) and the storage tank (4) are arranged in parallel on the primary circuit (1) A system as claimed in any preceding claim comprising a control unit including control devices and a central control configured to control the control devices. System according to the preceding claim in combination with claim 2, in which the control unit is configured so that the system adopts a winter configuration in which the cooled heat transfer fluid outlet (3) of the looping heat exchanger is connected fluidic with the inlet of the heating heat exchanger (23). System according to any one of the two preceding claims in combination with claim 6, in which the control unit is configured so that the system assumes a summer configuration in which the cooled heat transfer fluid outlet (33) of the heat exchanger loop is in fluid connection with the complementary upper tapping (51) of the complementary storage tank (40). System according to the preceding claim, in which the domestic hot water heat exchanger (13) is arranged downstream of the additional storage tank (40) so that the additional storage tank (40) at least partially supplies the heat exchanger domestic hot water (13). System according to any one of the preceding claims comprising a measurement module comprising at least one temperature sensor. Process for the production of domestic hot water and/or heating by a system according to any one of the preceding claims comprising, in a winter configuration, the circulation of heat transfer fluid from the looping heat exchanger (31) towards the inlet ( 23) of the heating heat exchanger (22). Process for producing domestic hot water and/or heating according to the preceding claim by a system according to any one of Claims 1 to 13 in combination with Claim 6 comprising, in a summer configuration, the circulation of heat transfer fluid from the loop heat exchanger (31) to the additional storage tank (40). Process for producing domestic hot water and/or heating according to the preceding claim comprising the circulation of heat transfer fluid from the additional storage tank (40) to the domestic hot water heat exchanger (13).