CN204963253U - Solar thermal energy electricity generation thermal -arrest heat -retaining device - Google Patents

Abstract

A heat collection and storage device for solar thermal power generation. A high-temperature tank, an oil-water heat exchanger, a low-temperature tank, a heat transfer oil pump, a first control valve, a solar heat collection field, and a second control valve are connected in series to form a circuit. A third control valve is connected in parallel on the pipelines on both sides of the first control valve, and a fourth control valve is connected in parallel on the pipeline between the second control valve and the high-temperature tank, and one end of the fourth control valve is connected to the top of the high-temperature tank; the four control valves It is used to switch the daytime and nighttime operation modes of the system. The third control valve and the first control valve are connected in parallel to control the flow direction of the low-temperature tank working medium, and the second control valve and the fourth control valve are connected in parallel to control the flow direction of the high-temperature tank working medium; it can be operated In the heat collection and heat storage operation mode during the day and the shutdown antifreeze mode at night, the heat collection pipes and connecting pipes in the heat collection field of this system are in an empty state at night, so there is no need for natural gas boilers to prevent freezing, and the heat collection pipes are purged by pressure difference , does not require power consumption.

Description

A heat collection and storage device for solar thermal power generation

technical field

The utility model belongs to the technical field of solar light and heat utilization, in particular to a heat collecting and storing device for solar thermal power generation.

Background technique

my country is a country that uses coal as its basic energy source. The extensive use of coal has brought a huge impact on the environment and the global climate. The increasing smog and greenhouse effect threaten the survival of human beings. In order to improve the living environment of human beings, it is necessary to reduce the proportion of fossil energy in my country's energy structure and vigorously develop renewable energy.

Solar energy is a very clean and renewable energy. The solar energy reaching the earth's surface in a year is about 5.5×10 ²⁶ J, which is equivalent to 10 ⁴ times the total energy consumed by human beings in a year. Therefore, solar energy can be regarded as an inexhaustible new energy source. According to the forecast of the International Energy Agency, by 2050, solar power will account for more than 25% of the global electricity supply.

Solar energy resources are available day and night, so solar thermal power stations generally shut down at night. After the shutdown, the heat-absorbing working medium in the solar collector field must be antifreeze. The antifreeze solution equipped with natural gas boilers increases power generation costs and reduces economy.

Contents of the invention

In order to solve the above problems, the purpose of this utility model is to provide a solar thermal power generation heat collection and storage device. The heat pipes and connecting pipes are empty at night, so there is no need for natural gas boilers to prevent freezing, and the pressure difference is used to purge the heat collecting pipes without consuming electric energy.

In order to achieve the above object, the technical scheme that the utility model adopts is:

A heat collection and storage device for solar thermal power generation, comprising a high temperature tank 10, a high temperature tank 10, an oil-water heat exchanger 1, a low temperature tank 3, a heat conduction oil pump 4, a first control valve 6, a solar heat collection field 7, and a second control valve 9 in series to form a circuit, the third control valve 5 is connected in parallel on the pipelines on both sides of the heat transfer oil pump 4 and the first control valve 6, and the fourth control valve 8 is connected in parallel on the pipelines of the second control valve 9 and the high temperature tank 10, and One end of the fourth control valve 8 communicates with the top of the high temperature tank 10 .

In the series circuit described above, the communication part of the high-pressure tank 10 is at the lower part or the bottom.

The heat transfer oil in the high temperature tank 10 is in a saturated state of high temperature and high pressure.

The heat transfer oil in the low temperature tank 3 is in an undersaturated state at low temperature and low pressure.

Compared with the prior art, in the scheme of the utility model, the heat collection circuit and the heat release circuit are independent and do not affect each other, and the heat release circuit can generate stable steam to ensure that the output power of the generator set is completely controllable and adjustable; The pressure difference between the tank and the low-temperature tank makes the high-temperature heat transfer oil flow through the oil-water heat exchanger to generate steam with various thermal parameters. Using the heat transfer oil steam to purge the heat collector tube does not require power consumption, which can effectively reduce the power consumption rate of the plant; The heat collecting tube is in an empty state, so there is no need to configure a natural gas boiler to prevent freezing.

Description of drawings

Accompanying drawing is a structural schematic diagram of the utility model.

detailed description

Embodiments of the present utility model will be described in detail below in conjunction with the accompanying drawings.

As shown in the figure, a heat collection and storage device for solar thermal power generation includes a high temperature tank 10, a high temperature tank 10, an oil-water heat exchanger 1, a low temperature tank 3, a heat conduction oil pump 4, a first control valve 6, a solar heat collection field 7, The second control valve 9 is connected in series in turn to form a circuit, the third control valve 5 is connected in parallel on the pipelines on both sides of the heat transfer oil pump 4 and the first control valve 6, and the fourth control valve 5 is connected in parallel on the pipelines of the second control valve 9 and the high temperature tank 10. valve 8, and one end of the fourth control valve 8 communicates with the top of the high temperature tank 10.

In the series circuit, the connection of the high pressure tank is at the lower part or the bottom.

The heat transfer oil in the high temperature tank 10 is in a saturated state of high temperature and high pressure.

The heat transfer oil in the low temperature tank 3 is in an undersaturated state at low temperature and low pressure.

The solar heat collecting field 7 can be a parabolic trough type or a linear Fresnel type, and is mainly used to focus sunlight and convert solar energy into heat energy.

The heat transfer oil high temperature tank 10 and the low temperature tank 3 are used to store heat to ensure the stability of the system output power when the solar radiation fluctuates; the heat transfer oil in the high temperature tank 10 is in a saturated state of high temperature and high pressure; An undersaturated state at low temperature and low pressure.

The heat conduction oil pump 4 is the power source of the whole series circuit.

The oil-water heat exchanger 1 is the connection between the solar heat collection and heat storage system and the steam power system. The high-temperature heat transfer oil heats the feedwater through the oil-water heat exchanger 1 to generate steam.

Four control valves are used to switch the daytime and nighttime operation modes of the system. The third control valve 5 and the first control valve 6 are connected in parallel to control the flow direction of the cryogenic tank 3. The second control valve 9 and the fourth control valve 8 are connected in parallel to control the The flow direction of the high temperature tank 10 working fluid.

The working principle of the utility model is: when the solar radiation conditions are good during the day, the third control valve 5 and the fourth control valve 8 are closed, the first control valve 6 and the second control valve 9 are opened, and the heat conduction oil pump 4 turns the low temperature The low-temperature heat-conducting oil in the tank 3 is pumped into the trough-type or Fresnel-type solar heat collecting field 7, and stored in the high-temperature tank 10 after being heated. The heat-conducting oil is in a saturated state of high temperature and high pressure. When the intensity of solar radiation changes, the temperature of the heat transfer oil entering the high temperature tank 10 is kept substantially constant by adjusting the flow rate of the heat transfer oil pump 4 to ensure the stability of the temperature of the heat transfer oil in the high temperature tank 10 . The pressure difference between the high-temperature tank 10 and the low-temperature tank 3 is used to make the high-temperature heat transfer oil flow through the oil-water heat exchanger 1 to generate steam with corresponding thermal parameters.

After the heat collection system is shut down at night, in order to prevent the heat transfer oil from solidifying in the heat collection pipes and connecting pipes, the scheme of emptying the heat transfer oil in the heat collection pipes is adopted. After the heat collection system is shut down, close the control valves, the first control valve 6 and the second control valve 9, and open the control valves, the third control valve 5 and the fourth control valve 8 in sequence, and the heat transfer oil saturated steam in the high temperature tank 10 is driven by the pressure difference. Down into the heat collection field 7, the heat transfer oil in the heat collection tube is blown into the low-temperature tank 3, and after the purging is completed, the control valves 8 and 5 are closed in turn. During the purging process, part of the heat transfer oil in the high temperature tank 10 will flash off, and the heat transfer oil vapor will be replenished. The temperature and pressure of the high temperature tank 10 will remain basically unchanged, and the heat transfer oil vapor will be liquefied into heat transfer oil after entering the low temperature tank 3, and will not cause an increase in pressure.

Embodiment one

The operation mode of the system is illustrated by taking biphenyl-biphenyl ether heat transfer oil as heat storage and heat storage working fluid as an example. During the day, close the control valves third control valve 5 and fourth control valve 8, open the first control valve 6 and second control valve 9, and the heat transfer oil pump 4 pumps the heat transfer oil at 110°C in the cryogenic tank 3 into the tank or Fresnel The Seoul-style solar heat collection field 7 is stored in a high-temperature tank 10 after being heated to 380°C. The heat transfer oil is in a saturated state, and the corresponding saturation pressure is about 0.8 MPa. When the solar radiation changes, by adjusting the flow rate of the heat transfer oil pump 4, the temperature of the heat transfer oil entering the high temperature tank 10 is kept at about 380° C., and the temperature of the heat transfer oil in the high temperature tank 10 is stabilized. The pressure difference between the high-temperature tank 10 and the low-temperature tank 3 is used to make the high-temperature heat transfer oil flow through the oil-water heat exchanger 1 to generate steam with corresponding thermal parameters.

After the heat collection system is shut down at night, close the first control valve 6 and the second control valve 9, open the third control valve 5 and the fourth control valve 8 in sequence, and the saturated steam of the heat transfer oil in the high temperature tank 10 enters under the pressure difference. The heat collecting field 7 blows the heat conduction oil in the heat collecting tube into the low temperature tank 3, and after the purge is completed, the control valves 8 and 5 are closed in sequence. During the purging process, part of the heat transfer oil in the high temperature tank 10 will flash off, and the heat transfer oil vapor will be replenished. The temperature and pressure of the high temperature tank 10 will remain basically unchanged, and the heat transfer oil vapor will be liquefied into heat transfer oil after entering the low temperature tank 3, and will not cause an increase in pressure.

Claims (2)

1. A heat collecting and storing device for solar thermal power generation, comprising a high-temperature tank (10), characterized in that a high-temperature tank (10), an oil-water heat exchanger (1), a low-temperature tank (3), a heat-conducting oil pump (4), The first control valve (6), the solar heat collecting field (7), and the second control valve (9) are connected in series in sequence to form a circuit, and the pipelines on both sides of the heat conduction oil pump (4) and the first control valve (6) are connected in parallel with the second Three control valves (5), the fourth control valve (8) is connected in parallel on the pipeline of the second control valve (9) and the high temperature tank (10), and one end of the fourth control valve (8) is connected with the high temperature tank (10) connected at the top. 2. A solar thermal power generation heat collection and heat storage device according to claim 1, characterized in that, in the series circuit, the connection part of the high pressure tank (10) is at the lower part or the bottom.