阅读说明：本技术 一种无压缩过程的分布式二氧化碳发电系统 (Non-compression distributed carbon dioxide power generation system ) 是由 张荻 王雨琦 谢永慧 于 2020-11-03 设计创作，主要内容包括：本发明公开了一种无压缩过程的分布式二氧化碳发电系统,其中,使用二氧化碳钢瓶直接获取常温高压的二氧化碳工质,进入透平中膨胀做功,做功完成后采用有机胺溶液吸收池回收。吸收池中的二氧化碳工质通过加热解吸,进入储气罐中。再生的吸收剂有机胺溶液,重新进入吸收池中吸收二氧化碳。这一发电系统无压缩过程,同时采用分布式的布置方法,根据后端用户需求便捷地调节功率。本发明的优势在于：系统部件较少,成本低,便于设计、控制及运行维护,可靠性高,能够有效减少排放,满足环保需要。(The invention discloses a distributed carbon dioxide power generation system without a compression process, wherein a carbon dioxide steel cylinder is used for directly obtaining a carbon dioxide working medium with normal temperature and high pressure, the carbon dioxide working medium enters a turbine to expand to do work, and an organic amine solution absorption tank is used for recovering after the work is finished. And the carbon dioxide working medium in the absorption tank enters a gas storage tank through heating desorption. And the regenerated absorbent organic amine solution enters the absorption pool again to absorb the carbon dioxide. The power generation system has no compression process, and simultaneously adopts a distributed arrangement method to conveniently adjust the power according to the requirements of back-end users. The invention has the advantages that: the system has the advantages of fewer components, low cost, convenience in design, control, operation and maintenance, high reliability, capability of effectively reducing emission and meeting the requirement of environmental protection.)

1. A distributed carbon dioxide power generation system without a compression process is characterized by comprising a carbon dioxide power generation system and a carbon dioxide recovery system, wherein the carbon dioxide power generation system comprises a steel cylinder (1), a carbon dioxide turbine (2), a power generator (3) and a carbon dioxide absorption pool (4); wherein the content of the first and second substances,

extracting a normal-temperature high-pressure liquid carbon dioxide working medium from a carbon dioxide steel cylinder (1), wherein the pressure is 7MPa, the temperature is 25 ℃, and the working medium enters a carbon dioxide turbine (2) to expand to do work; the carbon dioxide turbine (2) is coaxially connected with the generator (3), and the carbon dioxide working medium drives the carbon dioxide turbine (2) and the generator (3) to rotate in the expansion process so as to generate electric energy; the outlet pressure of the carbon dioxide turbine (2) is 0.6MPa, the outlet temperature depends on the isentropic efficiency of the turbine, and the carbon dioxide working medium at the outlet is in a gas-liquid mixed state and enters a carbon dioxide absorption pool (4); and recycling and reusing the carbon dioxide working medium through a carbon dioxide recovery system.

2. The distributed carbon dioxide power generation system without the compression process according to claim 1, wherein the carbon dioxide recovery system comprises a carbon dioxide absorption tank (4), a mixed liquid pump (5), a mixed liquid heater (6) and a carbon dioxide gas storage tank (7), the mixed liquid pump (5) pumps the organic amine solution which absorbs the carbon dioxide working medium in the carbon dioxide absorption tank (4) into the mixed liquid heater (6), carbon dioxide gas is desorbed by heating to obtain a regenerated absorbent organic amine solution, the desorbed carbon dioxide enters the carbon dioxide gas storage tank (7) for recovery, and the regenerated absorbent organic amine solution reenters the carbon dioxide absorption tank (4) to absorb the working medium discharged by the carbon dioxide power generation system.

3. A compression process free distributed carbon dioxide power generation system as claimed in claim 1, wherein the organic amine solution in the carbon dioxide absorption cell (4) is sodium glycinate.

4. A distributed carbon dioxide power generation system without compression process according to claim 1, characterized in that the organic amine solution in the carbon dioxide absorption cell (4) is enamine.

5. A distributed carbon dioxide power generation system without compression process according to claim 1, characterized in that the organic amine solution in the carbon dioxide absorption cell (4) is ethanolamine.

6. The distributed carbon dioxide power generation system without the compression process as claimed in claim 1, wherein the isentropic enthalpy drop corresponding to the inlet and outlet working medium states of the carbon dioxide turbine (2) is 33.77kJ/kg, and the corresponding outlet isentropic temperature is-53.11 ℃; the number Z of carbon dioxide turbines (2) required in the distributed carbon dioxide power generation system is calculated as follows:

where P is the power demanded by the back end user in kW,for the mass flow of a single carbon dioxide turbine (2), Δ h_isIs the isentropic enthalpy drop of the carbon dioxide turbine (2) and has the unit of kJ/kg, and eta is the isentropic efficiency of the carbon dioxide turbine (2).

Technical Field

The invention belongs to the field of carbon dioxide power generation, and particularly relates to a compression-process-free distributed carbon dioxide power generation system.

Background

In recent years, supercritical carbon dioxide working media are widely applied to various power generation systems, and brayton cycle adopted under the background of nuclear energy, solar energy, geothermal energy, waste heat utilization and the like is widely concerned. The excellent characteristics of the supercritical carbon dioxide Brayton cycle are mainly shown in the following steps: the power density is high, and the system volume is small; compared with a gas turbine, the temperature is low, and high-temperature resistant materials are not needed; the compression factor is small, and the compression power consumption can be reduced; belongs to single-phase circulation, has no phase change process and does not need to use a condenser. In the development process, the realization of the supercritical carbon dioxide brayton cycle is limited by the following points: working media in the system are difficult to maintain in a supercritical state all the time, and once the trans-critical physical property changes, the density and specific heat of the working media are changed greatly and are difficult to control; the single-stage pressure ratio of the compressor is difficult to improve; the cooling and sealing reliability of key equipment such as a compressor, a turbine and the like is insufficient; the cost of the compressor, the turbine and other equipment is high, and the economy is poor.

In summary, since the supercritical carbon dioxide brayton cycle system has many key components, it is difficult to ensure the reliability of each component during operation and achieve the required system efficiency. Therefore, it is necessary to further improve the practicability, reliability and economy of carbon dioxide power generation in consideration of simplification of the existing brayton cycle power generation system, particularly, a compressor component having a large difficulty in pneumatic design.

Disclosure of Invention

The invention aims to provide a distributed carbon dioxide power generation system without a compression process aiming at the defects of the prior art, provides a low-cost and convenient energy form by extracting a working medium from a carbon dioxide steel cylinder, generating power in a turbine and recovering the working medium, and has important engineering significance and wide application prospect.

The invention is realized by adopting the following technical scheme:

a distributed carbon dioxide power generation system without a compression process comprises a carbon dioxide power generation system and a carbon dioxide recovery system, wherein the carbon dioxide power generation system comprises a steel cylinder, a carbon dioxide turbine, a power generator and a carbon dioxide absorption pool; extracting a normal-temperature high-pressure liquid carbon dioxide working medium from a carbon dioxide steel cylinder, wherein the pressure is 7MPa, the temperature is 25 ℃, and the working medium enters a carbon dioxide turbine to expand to do work; the carbon dioxide turbine is coaxially connected with the generator, and the carbon dioxide working medium drives the carbon dioxide turbine and the generator to rotate in the expansion process, so that electric energy is generated; the outlet pressure of the carbon dioxide turbine is 0.6MPa, the outlet temperature depends on the isentropic efficiency of the turbine, and the carbon dioxide working medium at the outlet is in a gas-liquid mixed state and enters a carbon dioxide absorption pool; and recycling and reusing the carbon dioxide working medium through a carbon dioxide recovery system.

The invention has the further improvement that the carbon dioxide recovery system comprises a carbon dioxide absorption tank, a mixed liquid pump, a mixed liquid heater and a carbon dioxide gas storage tank, the mixed liquid pump pumps the organic amine solution which absorbs the carbon dioxide working medium in the carbon dioxide absorption tank into the mixed liquid heater, carbon dioxide gas is desorbed by heating to obtain a regenerated absorbent organic amine solution, the desorbed carbon dioxide enters the carbon dioxide gas storage tank for recovery, and the regenerated absorbent organic amine solution enters the carbon dioxide absorption tank again to absorb the working medium discharged by the carbon dioxide power generation system.

In a further improvement of the invention, the organic amine solution in the carbon dioxide absorption cell is sodium glycinate.

In a further improvement of the invention, the organic amine solution in the carbon dioxide absorption cell is enamine.

The invention is further improved in that the organic amine solution in the carbon dioxide absorption pool is ethanolamine.

The invention has the further improvement that the isentropic enthalpy drop corresponding to the inlet and outlet working medium states of the carbon dioxide turbine is 33.77kJ/kg, and the corresponding outlet isentropic temperature is-53.11 ℃; the number Z of carbon dioxide turbines required in the distributed carbon dioxide power generation system is calculated as follows:

where P is the power demanded by the back end user in kW,for mass flow of a single carbon dioxide turbine, Δ h_isThe isentropic enthalpy drop of the carbon dioxide turbine is expressed in kJ/kg, and eta is the isentropic efficiency of the carbon dioxide turbine.

Compared with the prior art, the invention has at least the following beneficial technical effects:

the invention provides a compression-process-free distributed carbon dioxide power generation system, aiming at the problem that a supercritical carbon dioxide Brayton cycle power generation system is difficult to realize high-efficiency operation. In a traditional supercritical carbon dioxide Brayton cycle, key components such as a turbine, a compressor, a heater, a cooler, a heat regenerator and the like are arranged, and it is very difficult to ensure the normal and efficient operation of all the key components. Therefore, the invention simplifies the compression process by using the carbon dioxide steel cylinder, directly obtains the high-pressure working medium to do work through expansion, and reduces the emission of carbon dioxide by adopting a recovery mode of the absorption tank. The power generation system has fewer components, low cost, convenient design, control, operation and maintenance and high reliability, and can be used in small-sized power equipment with smaller power consumption requirements, such as farming, small-sized factories and other scenes. By adopting a distributed arrangement method, the power can be conveniently adjusted according to the requirements of back-end users. Meanwhile, the carbon dioxide absorption tank is adopted for recycling, so that the emission is effectively reduced, and the environment-friendly requirement is met. In conclusion, the method has important engineering significance and wide application prospect.

Drawings

Fig. 1 is a carbon dioxide power generation system diagram of a distributed carbon dioxide power generation system without a compression process of the present invention.

Fig. 2 is a carbon dioxide recovery system diagram of a distributed carbon dioxide power generation system without a compression process of the present invention.

Description of reference numerals:

the system comprises a carbon dioxide steel bottle 1, a carbon dioxide turbine 2, a power generator 3, a carbon dioxide absorption tank 4, a mixed liquid pump 5, a mixed liquid heater 6 and a carbon dioxide gas storage tank 7.

Detailed Description

The invention will be further explained with reference to the drawings.

The invention provides a compression-process-free distributed carbon dioxide power generation system which comprises a carbon dioxide power generation system and a carbon dioxide recovery system.

Referring to fig. 1, the carbon dioxide power generation system includes components including a carbon dioxide cylinder 1, a carbon dioxide turbine 2, a generator 3, and a carbon dioxide absorption tank 4. Wherein the working medium in the carbon dioxide absorption tank 4 is organic amine solution such as sodium glycinate or enamine, ethanolamine and the like.

The working process of the distributed carbon dioxide power generation system is as follows: extracting a normal-temperature high-pressure liquid carbon dioxide working medium from a carbon dioxide steel cylinder 1, wherein the pressure is 7MPa, the temperature is 25 ℃, and the working medium enters a carbon dioxide turbine 2 for expansion. The carbon dioxide turbines 2 are coaxially connected with the generator 3, and the carbon dioxide working medium drives the carbon dioxide turbines 2 and the generator 3 to rotate to do work in the expansion process to generate electric energy. The outlet pressure of the distributed carbon dioxide turbine 2 is 0.6MPa, the outlet temperature depends on the isentropic efficiency of the turbine, and the carbon dioxide working medium at the outlet is in a gas-liquid mixed state and enters the carbon dioxide absorption pool 4 for recovery and reuse.

The physical properties of the carbon dioxide are checked, the isentropic enthalpy drop corresponding to the working medium states of the inlet and the outlet of the carbon dioxide turbine 2 is 33.77kJ/kg, and the isentropic temperature corresponding to the outlet is-53.11 ℃. The number Z of carbon dioxide turbines 2 required in the distributed carbon dioxide power generation system is calculated as follows:

where P is the power demanded by the back end user in kW,for the mass flow of the individual carbon dioxide turbines 2,. DELTA.h_isIs the isentropic enthalpy drop of the carbon dioxide turbine 2, with the unit of kJ/kg, and eta is the isentropic efficiency of the carbon dioxide turbine 2.

Referring to fig. 2, the carbon dioxide recovery system includes a carbon dioxide absorption tank 4, a mixed liquid pump 5, a mixed liquid heater 6, and a carbon dioxide gas tank 7.

The recovery process of the carbon dioxide working medium comprises the following steps: and pumping the organic amine solution which absorbs the carbon dioxide working medium in the carbon dioxide absorption tank 4 into a mixed solution heater 6 by a mixed solution pump 5, desorbing carbon dioxide gas by a heating method, and simultaneously obtaining a regenerated absorbent organic amine solution. The desorbed carbon dioxide gas enters a carbon dioxide gas storage tank 7 for recovery, and the regenerated absorbent organic amine solution enters a carbon dioxide absorption tank 4 again for recycling to absorb working media discharged by a carbon dioxide power generation system.