CN114688746A - A natural circulation solar heat storage system - Google Patents

Abstract

The invention discloses a natural circulation type solar heat storage system, which belongs to the technical field of solar heat collection and solves the problem of low heat utilization rate of a solar heat collection system in the prior art. The invention is used for natural circulation collection of medium and small heat energy, and adopts a groove type reflector solar heat collection device and natural circulation heat conduction and heat storage.

Description

A natural circulation solar heat storage system

technical field

The invention belongs to the technical field of solar heat collection, and in particular relates to a natural circulation type solar energy heat storage system.

Background technique

Trough solar thermal power generation is a technology that uses a trough condenser to concentrate sunlight on a line for heat collection. A tubular heat collector is installed on this line to absorb solar energy and heat the heat transfer medium. , and then use the power cycle of steam to generate electricity. The parabolic surface of the trough concentrator tracks the sun in one dimension, the concentration ratio is 10-100, and the temperature can reach 400 °C. The trough solar thermal power generation technology has been developed in the mid-1980s. A 354MW trough concentrating thermal power station has been installed in California, USA. Its working medium is heat transfer oil, and the heat exchanger can make the heat transfer oil generate nearly 400 MW. ℃ superheated steam to drive the steam turbine to generate electricity.

The trough solar thermal power generation system mainly includes a heat collection system, a heat storage system, a heat exchange system and a power generation system. Among them, the technology of heat exchange system and power generation system is relatively mature. It is widely used, and there is no obstacle in the development of trough solar thermal power generation system technology in my country. The main factors affecting the development of trough solar thermal power generation technology in China are the heat collection system and the heat storage system. The heat collection system is mainly composed of a heat collection tube, a heat collection mirror, a support structure and a control system; the heat storage system is mainly composed of a heat storage tank and a heat storage medium.

At present, the trough solar collector system needs large thermal energy storage and conversion equipment to store, convert, and use the collected thermal energy. The investment cost is high, the equipment occupies a large area, and the heat collector pipes are laid for a long time, resulting in a large loss of thermal energy.

SUMMARY OF THE INVENTION

The purpose of this invention is to:

In order to solve the problem of low thermal energy utilization rate of the solar heat collection system in the prior art, a natural circulation solar heat storage system is provided.

The technical scheme adopted in the present invention is as follows:

A natural circulation type solar energy heat storage system includes a base frame, a support base is connected to the base frame, a bottom support shaft is installed on the support base, and a reflector and a heat absorption pipe are respectively connected to the bottom rotating shaft, so the The outer surface of the heat-absorbing pipe is covered with a heat-resistant thermal insulation layer, and a circulating fluid cavity is arranged inside the heat-absorbing pipe. Both ends of the pipe are connected, and a heat collecting device is installed on the periphery of the heat-conducting pipe.

Further, the heat collection device includes a collection device housing, and a flow channel plate that divides the interior of the collection device housing into upper and lower layers is installed in the collection device housing, and a heat storage medium inlet pipe and a heat storage medium are connected to the collection device housing. The medium outlet pipe, the heat storage medium inlet pipe and the heat storage medium outlet pipe are respectively connected to the lower layer and the upper layer in the casing of the collecting device.

Further, the cross section of the collecting device housing is a right-angled trapezoid, the top surface of the collecting device housing is slope-shaped, and the installation direction of the return pipe is parallel to the top surface of the collecting device housing.

Further, two of the heat collection devices are symmetrically arranged, and the heat conduction pipes between the return pipe and the heat absorption pipe are respectively installed through the two heat collection devices. The part is a closed structure.

Further, a plurality of heat-conducting fins are connected to the heat-conducting pipe.

To sum up, due to the adoption of the above technical solutions, the beneficial effects of the present invention are:

1. The present invention adopts a solar reflector heat collection structure, and a volatile heat-conducting medium is introduced into the heat-absorbing pipe at the focus of the reflector, and the heat-conducting medium located in the heat-absorbing pipe is rapidly volatilized into a gas when heated, and then rises into the heat-conducting pipe for heat transfer. It is condensed into a liquid medium in the uppermost return pipe and then falls down to the heat absorption pipe to continue the circulation process. Compared with the trough solar heat collecting system in the prior art, the system of the present invention can build a It has the advantages of short laying pipelines, less heat loss, and can be directly used as a small heat storage unit for heat storage and energy supply. big loss problem.

2. The present invention greatly prolongs the residence time of the heat storage medium in it through the flow channel plate and the inlet and outlet pipe channels, and enhances the effect of heat conduction; The backflow of the medium improves the circulation efficiency.

3. The present invention can also adopt the V-shaped return pipe shape. After the medium is evaporated, it can rise to the higher ends along the pipeline, which lengthens the stroke of the medium in the condensation stage. Condensing and refluxing while moving in the middle enhances the effect of condensation.

Description of drawings

FIG. 1 is a system structure diagram of the present invention.

Marking in the figure: 1- chassis, 2- support base, 3- bottom support shaft, 4- mirror, 5- heat absorption pipe, 6- heat conduction pipe, 7- return pipe, 8- heat collection device, 9- flow Road plate, 10-heat storage medium inlet pipe, 11-heat storage medium outlet pipe.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

Example 1

A natural circulation solar heat storage system comprises a base frame 1, a support base 2 is connected to the base frame 1, a bottom support shaft 3 is installed on the support base 2, and the bottom rotating shaft is respectively connected with a reflector 4 and a heat absorption pipe 5, The outer surface of the heat absorption pipe 5 is covered with a heat-resistant thermal insulation layer, and a circulating fluid cavity is arranged inside the heat absorption pipe 5. The circulating fluid cavity is connected with a return pipe 7 through a plurality of heat conduction pipes 6, and the return pipe 7 is connected to the suction pipe through the support of the return pipe 7. Both ends of the heat pipe 5 are connected, and a heat collecting device 8 is installed on the periphery of the heat pipe 6 . Preferably, a plurality of heat-conducting fins are connected to the heat-conducting pipe 6 .

The solar reflector 4 is used to collect heat, and the volatile heat-conducting medium is introduced into the heat-absorbing pipe 5 at the focus of the reflector 4, and the heat-conducting medium located in the heat-absorbing pipe 5 is quickly volatilized into gas when heated, and rises into the heat-conducting pipe 6 for transmission. The heat rises to the uppermost return pipe 7 and condenses into a liquid medium, and then falls back down to the heat absorption pipe 5 to continue the circulation process. The system of the present invention is built into a small solar heat storage system through the principle of natural circulation, and has the advantages of short laying pipelines. , The advantages of less heat loss and can be directly used as a small heat storage unit for heat storage and energy supply, which solves the problem of large heat loss caused by the trough solar collector system usually transporting heat through long-distance pipelines for circulation.

Example 2

On the basis of Embodiment 1, the heat collecting device 8 includes a collecting device shell, and a flow channel plate 9 that divides the inside of the collecting device shell into upper and lower layers is installed in the collecting device shell, and a heat storage medium inlet pipe is connected to the collecting device shell. 10 and the heat storage medium outlet pipe 11, the heat storage medium inlet pipe 10 and the heat storage medium outlet pipe 11 respectively communicate with the lower layer and the upper layer in the housing of the collecting device.

Preferably, the cross section of the collecting device housing is a right-angled trapezoid, the top surface of the collecting device housing is slope-shaped, and the installation direction of the return pipe 7 is parallel to the top surface of the collecting device housing.

Through the flow channel plate 9 and the inlet and outlet pipe channels, the residence time of the heat storage medium in it is greatly prolonged, and the effect of heat conduction is enhanced; backflow to improve cycle efficiency.

Example 3

On the basis of Example 1, two heat collection devices 8 are symmetrically arranged, and the heat transfer pipes 6 between the return pipe 7 and the heat absorption pipe 5 are respectively installed through the two heat collection devices 8, and the return pipes 7 are V-shaped. The shape is set, and both ends of the return pipe 7 are closed structures.

The shape of the V-shaped return pipe 7 enables the medium to rise to the higher ends along the pipeline after evaporation, which lengthens the stroke of the medium in the condensation stage. With the design of multiple heat conduction pipes 6, it can move while condensing during the stroke. Reflux to enhance the effect of condensation.

The workflow of the present invention is implemented as follows:

The heat storage system of the present invention is based on a trough solar heat collection system, and a volatile heat-conducting medium is introduced into the heat-absorbing pipe 5 at the focus of the reflector 4 , and the heat-conducting medium located in the heat-absorbing pipe 5 is stored in the solar reflector 4 . When the sunlight is concentrated on the heat-absorbing pipe 5, it is heated and volatilized into a gas that rises into the heat-conducting pipe 6, and part of it rises to the return pipe 7 above the heat-conducting pipe 6. When the gaseous medium passes through the heat-conducting pipe 6, it passes through the heat-conducting pipe 6. The wall conducts heat transfer with the heat storage medium in the heat collection device 8, and the heat transfer medium rising to the uppermost return pipe 7 is condensed into a liquid state in the communicating inner pipe of the return pipe 7, and then falls back down to the heat absorption pipe 5. Continuing the cycle process, the heat energy collected through the heat storage medium can be directly connected to the related systems and devices that need heating and energy supply, and can also be used as energy supply for small power generation devices, realizing the use of natural circulation to complete short-tube solar energy for small and medium-sized devices. heat storage.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (5)

1. A natural circulation solar heat storage system, characterized in that it comprises a base frame (1), a support base (2) is connected to the base frame (1), and a bottom is installed on the support base (2) A support shaft (3), the bottom rotating shaft is respectively connected with a reflector (4) and a heat absorption pipe (5), the outer surface of the heat absorption pipe (5) is covered with a heat-resistant thermal insulation layer, and the heat absorption pipe (5) A circulating fluid cavity is provided inside, and the circulating fluid cavity is connected with a return pipe (7) through a plurality of heat conduction pipes (6), and the return pipe (7) is connected with the heat absorption pipe (5) through the return pipe (7) bracket. The two ends are connected, and a heat collecting device (8) is installed on the periphery of the heat conducting pipe (6). 2. A natural circulation solar heat storage system according to claim 1, characterized in that, the heat collecting device (8) comprises a collecting device casing, and a collecting device casing is installed in the collecting device casing to separate the inside of the collecting device casing The flow channel plate (9) is formed into upper and lower layers, the collecting device shell is connected with a heat storage medium inlet pipe (10) and a heat storage medium outlet pipe (11), a heat storage medium inlet pipe (10) and a heat storage medium outlet pipe (11) The lower layer and the upper layer in the housing of the collecting device are respectively communicated. 3. A natural circulation solar heat storage system according to claim 2, characterized in that, the cross section of the housing of the collecting device is a right-angled trapezoid, the top surface of the housing of the collecting device is a slope, and the return pipe (7 ) is installed parallel to the top surface of the collector housing. 4. A natural circulation solar heat storage system according to claim 3, characterized in that, two of the heat collection devices (8) are symmetrically arranged, and the return pipe (7) and the heat absorption pipe (5) are arranged symmetrically. The heat transfer pipes (6) between the two heat collecting devices (8) are respectively installed, the return pipes (7) are arranged in a V-shape, and the two ends of the return pipes (7) are closed structures. 5 . The natural circulation solar heat storage system according to claim 1 , wherein a plurality of heat conducting fins are connected to the heat conducting pipe ( 6 ). 6 .

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