CN107388337B - A distributed high-efficiency energy-saving phase change heat storage system - Google Patents

Abstract

The invention relates to a distributed efficient energy-saving phase-change heat storage system which comprises a heat storage loop and an output loop, wherein the heat storage loop consists of a phase-change heat storage main body, a heat exchanger and an electric heater, the heat storage loop comprises a new energy heat supply mode and an electric heating mode, the phase-change heat storage main body and the heat exchanger are connected to form heat storage circulation in the new energy heat supply mode, the phase-change heat storage main body and the electric heater are connected to form heat storage circulation in the electric heating mode, the output loop comprises a direct output mode and an electric heating auxiliary heating mode, an inlet and an outlet of the phase-change heat storage main body are respectively connected with a cold water inlet and a hot water outlet in the direct output mode, and a water inlet of the phase-change heat storage main body is connected with a cold. Compared with the prior art, the invention has the advantages of flexible arrangement, small occupied area, large heat storage capacity, quick and convenient heat storage/utilization, and the like.

Description

A distributed high-efficiency energy-saving phase change heat storage system

technical field

The invention relates to a phase change heat storage system, in particular to a distributed high-efficiency energy-saving phase change heat storage system.

Background technique

At present, the demand for heating in residential quarters and new rural areas is gradually increasing, and the burden on traditional boiler equipment is increasing. To varying degrees, there are deficiencies such as complex heating pipelines, high energy consumption, and inconvenient maintenance, resulting in lengthy heating pipelines and cost of coal and electricity. High, unstable heating and other shortcomings.

Traditional household heat storage units mostly use water tank liners, which have the disadvantages of weak heat storage capacity and large space occupation, and the internal water will be affected by repeated heating or long-term storage. At the same time, due to the small sensible heat storage of water, it is impossible to make full use of industrial waste heat, solar energy and other resources to achieve the ideal effect of saving energy.

A phase change material is a material that changes its phase state (such as solid to liquid) with temperature changes. During the phase change process, the phase change material will absorb or release a large amount of heat, which is called the latent heat of phase change, and the phase change process The temperature is basically constant, so the phase change material can store more heat than water in the same temperature range. The current research on phase change heat storage is still immature, and there are disadvantages such as slow heat conduction of phase change materials, uneven distribution of heat exchange tubes buried in phase change materials, low heat exchange efficiency, and low design heat storage, etc. It hinders the development and utilization of phase change heat storage systems.

Check the existing related inventions and utility model patents. The invention patent with the patent application number CN201210108199.0 discloses a phase-change heat storage system. A phase-change heat storage material is filled between the heat exchanger and the container to form a heat storage unit. Then at least one heat storage unit is connected in parallel on the heat medium delivery pipeline. The system's container and heat exchange area are not large, and it does not have a special controller to intelligently control the input and output of heat. The patent application number is CN201520822183.5 utility model patent discloses a phase-change solar water heating system, in which phase-change materials are heated by solar collectors or electric heaters. The cold fluid of the system is directly output after passing through the solar collector, electric heater, and heat storage heat pool in sequence. When the temperature of the heat storage heat pool is lower than the limit value, the internal residual heat is not recycled, thereby reducing the energy utilization rate.

Contents of the invention

The object of the present invention is to provide a distributed high-efficiency energy-saving phase-change heat storage system in order to overcome the above-mentioned defects in the prior art.

The purpose of the present invention can be achieved through the following technical solutions:

A distributed high-efficiency energy-saving phase change heat storage system, including a heat storage circuit and an output circuit composed of a phase change heat storage body, a heat exchanger and an electric heater,

The heat storage circuit includes a new energy heating mode and an electric heating mode. In the new energy heating mode, the phase change heat storage body is connected to the heat exchanger to form a heat storage cycle. In the electric heating mode, the phase change heat storage The main body and the electric heater are connected to form a heat storage cycle,

The output circuit includes a direct output mode and an electric heating auxiliary heating mode. In the direct output mode, the inlet and outlet of the phase change heat storage body are respectively connected to the cold water input port and the hot water output port. In the electric heating auxiliary heating mode, the phase change The water inlet of the heat storage body is connected to the cold water input port, and the water outlet is connected to the electric heater and the hot water output port in turn.

As a preferred embodiment, the phase-change heat storage body, the heat exchanger and the first circulating pump are connected in sequence to form a heat storage loop, and a first three There is also a second three-way valve on the pipeline between the first circulation pump and the phase change heat storage body, wherein the other interface of the first three-way valve is connected to the electric heater, and the output from the electric heater is The water outlet leads to two branches, one of which is directly connected to the hot water outlet, and the other is connected back to the phase change heat storage body, and the other interface of the second three-way valve is connected to the cold water pipeline, and the second circulation pump.

As a more preferred embodiment of the above, another branch led from the water outlet of the electric heater is connected to the water inlet of the second circulation pump of the cold water pipeline, and returns to the phase change heat storage through the second circulation pump main body.

As a more preferred embodiment of the above, a flow control valve is respectively arranged on the heat exchanger, the first circulating pump, the hot water output port, the cold water input port, and the branch where the electric heater is connected to the cold water pipeline. The control valve, the first three-way valve, and the second three-way valve are also connected to a PLC controller, and the PLC controller controls each valve switch to realize pipeline switching.

As a further preference of the above-mentioned more preferred embodiment, temperature sensors are respectively provided in the phase change heat storage body, at the inlet and outlet of the phase change heat storage body, and at the outlet of the electric heater, and a pressure sensor is also provided at the outlet of the electric heater. Sensors are respectively provided with flow sensors at the water outlets of the first circulation pump and the second circulation pump, and the temperature sensor, pressure sensor and flow sensor are all fed back and connected to the PLC controller.

As a preferred embodiment, the phase change heat storage body includes at least one heat storage unit, and the heat storage unit includes an outer shell, an inner tank, a heat exchange tube group, a metal corrugated fin set and a TP valve, wherein the outer shell and inner tank adopt Made of stainless steel, insulation material is filled between the outer shell and the inner tank, phase change material is filled between the heat exchange pipe and metal corrugated fins, and the TP valve is installed on the discharge pipe of the heat storage unit. It will automatically open when the internal pressure and temperature are too high, which plays a role of safety protection.

As a more preferred embodiment of the above-mentioned preferred embodiment, the phase-change heat storage body includes a plurality of heat storage units connected in series and parallel, wherein the inlet main pipeline branches out of the water inlet branch and is respectively connected to the water inlet of each heat storage unit, The water outlet of each heat storage unit is also connected to the outlet main pipeline through the confluence of pipelines. There is also a pipeline switching valve between the water outlets of two adjacent heat storage units, and a branch is drawn from the pipeline switching valve to connect to the lower pipeline. On the water inlet branch of a heat storage unit, a cut-off valve for adjusting the series-parallel connection state of the heat storage units is provided on the water inlet branch.

As a further preference of the above-mentioned more preferred embodiment, a water inlet valve is further provided at the water inlet of the heat storage unit.

Compared with the prior art, the present invention has the following advantages:

(1) Selecting a phase change material with a suitable phase change temperature and high heat storage density to replace medium water as the filling material of the heat storage device can effectively reduce the space volume of the device, improve heat storage efficiency, and facilitate heat removal and release.

(2) The heat storage body can adjust the number of heat storage units and series-parallel connection according to the number of users, required heat, and required temperature. The PLC controller is used to adjust the various parts of the system to obtain more suitable water temperature and water volume, making the system more intelligent.

(3) A variety of heat supply sources can be selected. In the case of sufficient solar energy, solar heat can be used for heat storage, and in the case of insufficient solar energy, it can be directly heated by electricity. When the heat released by the heat storage body is insufficient, the temperature of the output circuit is lower than the set value but higher than the ambient temperature. At this time, the electric heating auxiliary heating can be turned on to utilize this part of the heat, thereby improving efficiency and saving electricity costs.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic diagram of the series-parallel connection of the heat storage units of the phase change heat storage body of the present invention;

In the figure, 1 is the phase change heat storage main body, 1-1 is the heat exchange tube group, 1-2 is the liner, 1-3 is the shell, 1-4 is the phase change material, 1-5 is the TP valve, 2 is the Electric heater, 3-1, 3-2, 3-3, 3-4 are temperature sensors, 4-heat exchanger, 5-1, 5-2, 5-3 are flow control valves, 6-PLC controller , 7-1 is the first three-way valve, 7-2 is the second three-way valve, 8 is the hot water output port, 9 is the cold water input port, 10-1 is the first circulation pump, 10-2 is the second circulation Pump, 11-1, 11-2 are flow sensors, 12-pressure sensor, 100-heat storage unit, 200-water inlet valve, 300-pipeline switching valve, 401-inlet main line, 402-outlet main line.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

A distributed high-efficiency energy-saving phase change heat storage system, as shown in Figure 1, includes a heat storage circuit and an output circuit composed of a phase change heat storage body 1, a heat exchanger 4, and an electric heater 2. The heat storage circuit Including the new energy heating mode and the electric heating mode. In the new energy heating mode, the phase change heat storage body 1 and the heat exchanger 4 are connected to form a heat storage cycle. In the electric heating mode, the phase change heat storage body 1 and the The electric heater 2 is connected to form a heat storage cycle. The output circuit includes a direct output mode and an electric heating auxiliary heating mode. In the direct output mode, the inlet and outlet of the phase change heat storage body 1 are respectively connected to the cold water input port 9 and the hot water The output port 8, in the electric heating auxiliary heating mode, the water inlet of the phase change heat storage body 1 is connected to the cold water input port 9, and the water outlet is connected to the electric heater 2 and the hot water output port 8 in sequence.

As a preferred embodiment, the phase-change heat storage body 1, the heat exchanger 4 and the first circulation pump 10-1 are sequentially connected to form a circuit, and the pipeline between the phase-change heat storage body 1 and the heat exchanger 4 is further A first three-way valve 7-1 is provided, and a second three-way valve 7-2 is also provided on the pipeline between the first circulating pump 10-1 and the phase change heat storage body 1, wherein the first three-way valve The other interface of 7-1 is connected to the electric heater 2, and two branches are drawn from the water outlet of the electric heater 2, one of which is directly connected to the hot water output port 8, and the other is connected back to the phase change heat storage body 1. The other interface of the second three-way valve 7-2 is connected to the cold water pipeline, and the second circulation pump 10-2 is arranged on the cold water pipeline. More preferably as the above-mentioned preferred embodiment, another branch drawn from the water outlet of the electric heater 2 is connected to the water inlet of the second circulation pump 10-2 of the cold water pipeline, and passes through the second circulation pump 10 -2 returns to the phase-change heat storage main body 1; the heat exchanger 4 and the first circulation pump 10-1, the hot water output port 8, the cold water input port 9, and the branch road where the electric heater 2 is connected to the cold water pipeline are respectively provided with Flow control valve, the flow control valve, the first three-way valve 7-1, and the second three-way valve 7-2 are also connected to the PLC controller 6, and the PLC controller 6 controls each valve switch to realize pipeline switching; In the phase change heat storage main body 1, at the inlet and outlet of the phase change heat storage main body 1, and at the outlet of the electric heater 2, temperature sensors are respectively provided, and a pressure sensor 12 is also provided at the outlet of the electric heater 2. 10-1 and the second circulation pump 10-2 are respectively provided with flow sensors at the water outlets, and the temperature sensor, pressure sensor 12 and flow sensor are all fed back to the PLC controller 6 .

As a preferred embodiment, the phase change heat storage body 1 includes at least one heat storage unit 100, and the heat storage unit 100 includes an outer shell 1-3, an inner tank 1-2, a heat exchange tube group 1-1, and metal corrugated fins. Group and TP valve 1-5, wherein, the shell 1-3 and the inner tank 1-2 are made of stainless steel, between the shell 1-3 and the inner tank 1-2 is also filled with insulation material, phase change material 1-4 It is filled between the heat exchange pipe and the metal corrugated fin. The TP valve 1-5 is installed on the discharge pipe of the heat storage unit 100. When the internal pressure and temperature of the heat storage are too high, it will automatically open to play a role of safety protection. . As a more preferred embodiment of the above-mentioned preferred embodiment, as shown in FIG. 2, the phase-change heat storage body 1 includes a plurality of heat storage units 100 connected in series and parallel, wherein the inlet main pipeline 401 is divided into outlet and inlet water branches, respectively connected to The water inlet of each heat storage unit 100 and the water outlet of each heat storage unit 100 are also connected to the main outlet pipeline 402 through a pipeline confluence, and a pipeline switching valve is also provided between the water outlets of two adjacent heat storage units 100 300, and the branch led from the pipeline switching valve 300 is connected to the water inlet branch of the next heat storage unit 100, and a cut-off valve for adjusting the series-parallel connection state of the heat storage unit 100 is provided on the water inlet branch. As a further preference of the above-mentioned more preferred embodiment, a water inlet valve 200 is further provided at the water inlet of the heat storage unit 100 .

Example 1

As shown in Figure 1, the present invention includes four parts: a phase change heat storage body 1, a heat storage circuit, an output circuit, and a PLC controller. The PLC controller 6 is connected to temperature sensors 3-1, 3-2, and 3-3. , 3-4, the flow sensors 11-1, 11-2 and the pressure sensor 12 monitor the temperature and pressure changes, and control the size of the flow and the switching of the pipeline. Among them, single or multiple heat storage units 100 are used inside the phase change heat storage body 1, which can be regulated by series and parallel connections and valves; electric heating mode and new energy heating mode are available under the heat storage circuit; the output circuit can directly output and auxiliary electric heating output .

Two heat storage modes will be introduced in detail below: As shown in Figure 1, when using new energy sources such as solar energy for heating, the first three-way valve 7-1 and the second three-way valve 7-2 are respectively connected to A1-C1 and A2 -C2, the medium obtains heat from the heat exchanger 4, passes through the flow control valve 5-1, the first circulation pump 10-1, the flow sensor 11-1, and the temperature sensor 3-2 and enters the phase change heat storage body 1 for heat storage. Then return to the heat exchanger 4 through the temperature sensor 3-3 to complete a cycle, and continue to store heat in the phase-change heat storage body 1 in this cycle; when the solar heat is insufficient, use the electric heating mode, the first three-way valve 7-1 and the second three-way valve 7-2 are respectively connected to A1, B1 and A2, B2, the flow control valves 5-2 and 5-3 are closed, the flow control valve 5-4 is opened, and the medium with a lower temperature is transferred from the phase change heat storage body After 1 comes out, it is heated by the electric heater 2, and then through the flow control valve 5-4, the second circulation pump 10-2, the flow sensor 11-2, and the temperature sensor 3-2 enter the phase change heat storage body 1 to complete the heat storage Once in a cycle, the heat is stored in the heat storage body through repeated cycles.

The output mode will be introduced in detail below: as shown in Figure 1, when the user needs heat, the first three-way valve 7-1 and the second three-way valve 7-2 are respectively connected to A1, B1 and A2, B2, and the flow control valve 5-2 and 5-3 are opened, the flow control valve 5-4 is closed, cold water enters from the cold water input port 9, passes through the flow control valve 5-3 in turn, the second circulating pump 10-2, the flow sensor 11-2, the temperature sensor 3-2 Enter the phase change heat storage body 1 to be heated, and then pass through the temperature sensor 3-3, the electric heater 2 (if the temperature is lower than the user's set value, turn on the electric heating auxiliary heating, otherwise do not turn on the electric heating), The temperature sensor 3-4 and the pressure sensor 12 flow out from the hot water outlet 8 at last.

The following will specifically introduce the series-parallel connection inside the heat storage body: Referring to FIG. 2 , the inside of the heat storage body 1 can be a single heat storage unit 100 or multiple heat storage units 100 connected in series and parallel. When the pipeline switching valve 300 is connected to pipelines a and b, it is in parallel mode at this time, and the medium flows in from the main inlet pipeline 401, and then flows into each water inlet branch by shunting (at this time, each water inlet branch is connected), and then enters each water inlet branch. The heat storage unit 100 performs heat exchange, and then the confluence is concentrated to the outlet main pipeline 402 to flow out; when the pipeline switching valve 300 is connected to the a and c pipelines, it is in series mode at this time (at this time, the shut-off valves on each water inlet branch are closed), The medium flows in from the main inlet pipe 401, then enters each heat storage unit 100 for heat exchange in turn, and finally flows out from the main outlet pipe 402. In this mode, the inlet and outlet fluids can obtain a larger temperature difference. When the heat supply from the heat source cannot satisfy multiple heat storage units, it is only necessary to close the valve 200 at the water inlet of the corresponding heat storage unit 100 to disconnect the heat storage unit 100, thereby adjusting the number of heat storage units 100 that are effectively used.

The above descriptions of the embodiments are for those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described here to other embodiments without creative effort. Therefore, the present invention is not limited to the above-mentioned embodiments. Improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims (6)

1. A distributed high-efficiency energy-saving phase change heat storage system, characterized in that it includes a heat storage circuit and an output circuit composed of a phase change heat storage body, a heat exchanger and an electric heater, The heat storage circuit includes a new energy heating mode and an electric heating mode. In the new energy heating mode, the phase change heat storage body is connected to the heat exchanger to form a heat storage cycle. In the electric heating mode, the phase change heat storage The main body and the electric heater are connected to form a heat storage cycle, The output circuit includes a direct output mode and an electric heating auxiliary heating mode. In the direct output mode, the inlet and outlet of the phase change heat storage body are respectively connected to the cold water input port and the hot water output port. In the electric heating auxiliary heating mode, the phase change The water inlet of the heat storage body is connected to the cold water input port, and the water outlet is connected to the electric heater and the hot water output port in turn; The phase-change heat storage main body, heat exchanger and first circulation pump are connected in sequence to form a loop, and a first three-way valve is provided on the pipeline between the phase-change heat storage main body and the heat exchanger, the first circulation pump and the first circulation pump There is also a second three-way valve on the pipeline between the phase-change heat storage bodies, wherein the other interface of the first three-way valve is connected to the electric heater, and two branches are drawn from the water outlet of the electric heater, wherein One is directly connected to the hot water output port, the other is connected back to the phase change heat storage body, and the other port of the second three-way valve is connected to a cold water pipeline, and a second circulation pump is arranged on the cold water pipeline; Another branch led from the water outlet of the electric heater is connected to the water inlet of the second circulation pump of the cold water pipeline, and returns to the phase-change heat storage body through the second circulation pump. 2. A distributed high-efficiency energy-saving phase change heat storage system according to claim 1, characterized in that cold water is connected between the heat exchanger and the first circulation pump, hot water output port, cold water input port, and electric heater Flow control valves are respectively arranged on the branches of the pipeline, and the flow control valve, the first three-way valve, and the second three-way valve are also connected to a PLC controller, and the PLC controller controls each valve switch to realize pipeline switching. 3. A distributed high-efficiency energy-saving phase change heat storage system according to claim 2, characterized in that, in the phase change heat storage body, at the entrance and exit of the phase change heat storage body, and at the outlet of the electric heater, respectively There is a temperature sensor, and a pressure sensor is provided at the outlet of the electric heater, and a flow sensor is respectively provided at the water outlet of the first circulation pump and the second circulation pump, and the temperature sensor, pressure sensor, and flow sensor are all fed back and connected to PLC control device. 4. A distributed high-efficiency energy-saving phase-change heat storage system according to claim 1, wherein the phase-change heat storage body includes at least one heat storage unit, and the heat storage unit includes an outer shell, an inner tank, a heat exchange Tube group, metal corrugated fin group and TP valve, in which the shell and inner tank are made of stainless steel, and insulation material is filled between the shell and the inner tank, and phase change material is filled between the heat exchange pipe and the metal corrugated fin During the period, the TP valve is installed on the discharge pipe of the heat storage unit. 5. A distributed high-efficiency energy-saving phase change heat storage system according to claim 4, characterized in that, the phase change heat storage body includes a plurality of heat storage units connected in series and parallel, wherein the main inlet pipeline is divided into The water inlet branch is respectively connected to the water inlet of each heat storage unit, and the water outlet of each heat storage unit is also connected to the main outlet pipeline through the confluence of pipelines. There is also a pipeline between the water outlets of two adjacent heat storage units. switch valve, and lead out the branch from the pipeline switching valve to the water inlet branch of the next heat storage unit. There is also a cut-off valve on the water inlet branch to adjust the series-parallel connection state of the heat storage unit where it is located. 6. A distributed high-efficiency energy-saving phase change heat storage system according to claim 5, wherein a water inlet valve is also provided at the water inlet of the heat storage unit.