Seawater utilization type power generation system

Abstract

[Problem] To provide a power generation system using a condenser of a power plant. [Solution] A seawater utilization type power generation system 10 is characterized by including: a steam turbine part 22 for rotating a generator by rotating by steam using heat energy; a condenser 24 for cooling the steam discharged by the steam turbine part 22 and converting the steam into condensate; an upstream side flow passage part 32 including a pump part 34 for pumping up seawater from the sea, and for allowing seawater to flow into the condenser 24; a downstream side flow passage part 36 for returning the sea water flowing out from the condenser 34 to the sea; a water turbine part 38 operated by seawater flowing in the downstream side flow passage part 36; and a water turbine power generation part 40 for generating power by using the rotation of the water turbine part 38.

Description

Seawater power generation system

[0001] The present invention relates to a seawater-based power generation system.

[0002] Conventionally, thermal power plants and nuclear power plants have been installed. For example, Patent Document 1 discloses a technology related to the present invention, in which a water turbine capsule-type hydroelectric power generating device is fixed with anchors on the riverbed of a drainage channel, such as a cooling water drainage channel attached to a nuclear power plant, a thermal power plant, a factory, or the like, or a drainage channel for discharging used water in a hydroelectric power plant, and the system converts wastewater energy into electrical energy, and the obtained electricity is passed through a power receiving facility on the ground to a branch-connected electrolysis tank to generate hydrogen and oxygen by electrolysis of water, and the generated hydrogen and oxygen are sent to a hydrogen storage device and an oxygen storage device via a compressor, respectively, and stored in the storage devices. The water turbine capsule-type hydroelectric power generating device is fixedly installed on the riverbed easily, safely, and stably without stopping the torrent of wastewater flowing in the drainage channel. The hydrogen and oxygen generation system utilizes wastewater energy and is characterized in that the system has a water conduit with a water control gate inside the capsule, and is connected between an intermediate section of the water conduit without a propeller turbine and an intermediate section with a propeller turbine built in, which can be switched between these two sections, and the propeller turbine and DC generator are connected in series. The branch-connection electrolysis cell is formed by separating the electrolysis cell into an anode cell for generating oxygen and a cathode cell for generating hydrogen, in order to prevent a decrease in purity and generation efficiency due to mixing of the generated hydrogen and oxygen. The anode cell and the cathode cell are connected via a connecting pipe on the outer surface of their bottoms, and a polymer membrane diaphragm is placed in the middle of the connecting pipe. The anode cell is connected via a connecting pipe to a water supply tank for supplying fresh water, so that the water levels in the electrolysis cell and the water supply tank are always maintained at a constant level.

[0003] Japanese Patent Application Laid-Open No. 2007-154542

[0004] Thermal power plants and nuclear power plants have steam turbines that use thermal energy to rotate steam to drive generators, and large amounts of seawater are used in the condensers that cool the steam discharged from the steam turbines.

[0005] The present invention provides a power generation system that utilizes a power plant condenser.

[0006] The seawater-utilizing power generation system of the present invention is characterized by comprising: a steam turbine that uses thermal energy to rotate using steam to rotate a generator; a condenser that cools and condenses the steam discharged from the steam turbine; an upstream flow passage section that includes a pump that draws seawater from the sea and allows the seawater to flow into the condenser; a downstream flow section that returns the seawater flowing out of the condenser to the sea; a water turbine section that operates using the seawater flowing through the downstream flow section; and a water turbine power generation section that generates electricity using the rotation of the water turbine section.

[0007] The seawater power generation system according to the present invention preferably further comprises a thermal power unit that obtains the thermal energy by burning fossil fuel.

[0008] The seawater power generation system according to the present invention preferably further comprises a nuclear power unit that obtains the thermal energy by nuclear fission of uranium fuel.

[0009] According to the present invention, it is possible to generate electricity using the condenser of a power plant.

[0010] 1 is a diagram showing a seawater-utilizing power generation system 10 according to an embodiment of the present invention.

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following, similar elements in all drawings will be designated by the same reference numerals, and duplicate explanations will be omitted. Furthermore, in the description below, previously described reference numerals will be used as necessary.

[0012] 1 is a diagram showing a seawater power generation system 10 according to an embodiment of the present invention. The seawater power generation system 10 includes a fuel tank section 12, a fuel distribution section 14, a boiler section 16, a dust collection section 18, a chimney section 20, a steam turbine section 22, a condenser 24, a generator 26, a transformer 28, a transmission tower 30, an upstream distribution section 32, a pump section 34, a downstream distribution section 36, a water turbine section 38, and a water turbine power generation section 40.

[0013] The fuel tank unit 12 is a tank that stores fuel to be supplied to the boiler unit 16. Although the fuel will be described as being, for example, natural gas, coal, or oil, other fuels, such as hydrogen or ammonia, may also be used.

[0014] The fuel distribution section 14 connects the boiler section 16 and the fuel tank section 12 and includes a pipe for distributing fuel so as to supply the fuel stored in the fuel tank section 12 to the boiler section 16 .

[0015] The boiler section 16 uses the thermal power obtained by burning fuel supplied from the fuel tank section 12 to convert water circulating through the steam turbine section 22 and the condenser 24 into steam and supplies it to the steam turbine section 22.

[0016] The dust collecting section 18 is a device that collects dust by applying an electric charge to fine particles of various types of dust contained in the fluid generated by burning fuel in the boiler section 16 and attracting the particles to a dust collecting electrode.

[0017] The chimney section 20 is a chimney that discharges the fluid after various types of dust have been collected by the dust collection section 18, and has a predetermined height so as to provide a chimney effect.

[0018] The steam turbine section 22 is a type of prime mover that converts the thermal energy of steam into the rotational energy of an impeller. The steam turbine section 22 ejects, expands, or changes direction of high-temperature, high-pressure steam through a nozzle or fixed blades to create a high-speed steam flow, which is then sprayed onto blades attached to a shaft to rotate the shaft, generating rotational energy. The rotational energy generated by the steam turbine section 22 is supplied to a generator 26.

[0019] The condenser 24 is a device that reduces the internal pressure of the condenser 24 (= turbine outlet pressure) below atmospheric pressure by condensing the steam from the steam turbine section 22 back into water, thereby significantly increasing the output and thermal efficiency of the steam turbine section 22. The condenser 24 is a surface condenser that has multiple pipes installed inside it and flows cooling water through the pipes to cool the steam. Since the steam and cooling water do not come into direct contact, clean condensate can be extracted. The condenser 24 is also set to a height of about 15 m above sea level.

[0020] The generator 26 is an electric power device that obtains electrical energy from rotational energy by utilizing electromagnetic induction. The generator 26 converts the rotational energy supplied from the steam turbine section 22 into electrical energy and transmits it to the transformer 28.

[0021] The transformer 28 changes the voltage of the electrical energy transmitted from the generator 26 and transmits it to the transmission tower 30 .

[0022] The transmission tower 30 is a structure for supporting an overhead power transmission line. The role of the transmission line is to transmit electricity between the transformer 28 and a substation, or between substations. The transmission tower 30 transmits the electrical energy transmitted from the transformer 28 to a substation (not shown).

[0023] The upstream flow section 32 is configured to include a pipe having one end connected to one end of a pipe inside the condenser 24 and the other end inserted into the sea to allow seawater to flow into the condenser 24.

[0024] The pump unit 34 is a machine for sucking up and sending liquid or gas by the action of pressure, generating a pressure difference using mechanical energy and converting it into kinetic energy of the liquid or gas. The pump unit 34 sucks up seawater from the other end of the upstream flow unit 32 and supplies it to the condenser 24.

[0025] The downstream circulation section 36 is configured to include a pipe having one end connected to the other end of the pipe inside the condenser 24 and the other end inserted into the sea for discharging seawater from the condenser 24.

[0026] The water turbine unit 38 is a rotary machine that converts water energy into mechanical energy. The water turbine unit 38 is provided in the downstream flow section 36. The seawater flowing through the downstream flow section 36 rotates its blades, and this rotational power is extracted and supplied to the water turbine power generation unit 40.

[0027] The water turbine power generation unit 40 is an electric power device that obtains electrical energy from rotational energy using electromagnetic induction. The water turbine power generation unit 40 converts the rotational energy supplied from the water turbine unit 38 into electrical energy. Here, the water turbine power generation unit 40 and the generator 26 have been described as being separate components, but they may also be integrated.

[0028] Next, the operation of the seawater power generation system 10 configured as described above will be described.

[0029] (Reasons why unused energy at power plants is not being used effectively) Electric power companies that operate thermal power plants, etc., simply leave the design and construction of the thermal power plants to the successful bidder and are not involved themselves, so they have no idea about how to make effective use of unused energy within the thermal power plants.

[0030] The successful bidder simply proceeds with the construction of the power plant to meet the predetermined specifications, and makes almost no suggestions for subsequent improvements. Furthermore, electric power companies generally do not have departments within their organizations that are focused on improving efficiency, and only have departments for regular repairs, safety measures, and improving usability.

[0031] Although it has been several decades since thermal power plants were built, there has been no thought given to using wastewater seawater. Also, because the amount of electricity generated at power plants is large, there is no consideration that even small improvements should be made compared to this amount of electricity generated.

[0032] Visitors to thermal power plants are rarely able to see the drainage system, and only see the turbines and buildings. Generally, the design of a thermal power plant is kept secret, so it cannot be viewed by the general public.

[0033] (Reasons why hydroelectric power generation has not progressed) Hydroelectric power generation (dams) require huge construction costs and also require the right to use the river. In Japan, the rights to use rivers are extremely complicated, which makes the procedures for construction cumbersome. For this reason, hydroelectric power generation has not progressed.

[0034] Building a new dam requires enormous construction costs, which is quite difficult in today's world where public works projects are under strict scrutiny. Micro-hydropower generation has become mainstream in recent years.

[0035] The seawater power generation system 10 according to the embodiment of the present invention provides a significant effect in addressing these issues. The seawater power generation system 10 uses fuel in a thermal power plant to operate a steam turbine section 22 and generate electricity with a generator 26. During this process, the steam in the steam turbine section 22 is cooled by a condenser 24 and returned to water, which is then circulated to a boiler section 18.

[0036] To cool the condenser 24, seawater pumped up by the pump section 34 flows into the condenser 24 from the upstream flow section 32, and the seawater flowing out of the condenser 24 operates the water turbine section 38 to generate electricity. The seawater used to cool the condenser 24 is simply returned to the sea, so if the potential energy of this seawater is recovered by the water turbine section 38, a significant effect can be achieved in that renewable electrical energy can be obtained. Here, the explanation is given assuming that the water turbine section 38 is used, but a hydroelectric power generation turbine may also be used. In addition to potential energy, kinetic energy (1 / 2 x m x v ２ ), pressure energy can also be utilized.

[0037] Furthermore, the seawater-utilizing power generation system 10 can be realized by small-scale modification of an existing thermal power plant, and there is almost no need to consider environmental issues, vested interests, etc. The seawater is not polluted.

[0038] The substation is located within the thermal power plant, and this can be achieved with low-cost investments such as purchasing and installing generators, and modifying transmission lines and the transmission system.

[0039] Furthermore, because it is a renewable energy source that uses seawater, the electricity generated using this renewable energy can reduce the fuel required for thermal power generation, which means it can be said to have a CO2 reduction effect.In addition, as a national policy project, there is a possibility that it will be eligible for subsidies from the government.

[0040] Unlike wind and solar power generation, it is possible to obtain stable energy that is not affected by natural weather. It also increases the degree of freedom in the operating range of thermal power plants. It can be realized not only in Japan but also overseas.

[0041] Here, the condenser 24 is set to a height of about 15 m above sea level, and the amount of water flowing through the upstream circulation section 32, the condenser 24, and the downstream circulation section 36 is 20 tons per second. Therefore, the effective head when seawater flows through the upstream circulation section 32, the condenser 24, and the downstream circulation section 36 is 15 m, and therefore, potential energy of 9.8 x 15 m x 20 tons = 2,940 kW can be used to rotate the water turbine section 38 to generate electricity.

[0042] In the above description, the condenser 24 is installed at a height of 15 m, but this height is just an example, and the condenser may be installed at a height of 15 m or more. In addition, in the above calculation formula, the thermal power plant is assumed to be 5 m above sea level, and the mean sea level is set to 0 m.

[0043] In the above description, the power plant to which the seawater-utilizing power generation system 10 is applied is described as a thermal power plant, but of course it can also be applied to other power plants, for example, a nuclear power plant equipped with a nuclear power unit that obtains thermal energy by nuclear fission of uranium fuel. Note that although the description here is of the use of seawater, it can also be applied to freshwater.

[0044] 10 Seawater-utilizing power generation system, 12 Fuel tank section, 14 Fuel distribution section, 16 Boiler section, 18 Dust collection section, 20 Chimney section, 22 Steam turbine section, 24 Condenser, 26 Generator, 28 Transformer, 30 Transmission tower, 32 Upstream distribution section, 34 Pump section, 36 Downstream distribution section, 38 Water turbine section, 40 Water turbine power generation section.

Claims

1. A seawater-utilizing power generation system comprising: a steam turbine that uses thermal energy to rotate using steam to rotate a generator; a condenser that cools and condenses the steam discharged from the steam turbine; an upstream flow passage section that includes a pump that draws seawater from the sea and allows the seawater to flow into the condenser; a downstream flow section that returns the seawater flowing out of the condenser to the sea; a water turbine section that is operated by the seawater flowing through the downstream flow section; and a water turbine power generation section that generates electricity using the rotation of the water turbine section.

2. A seawater-utilizing power generation system according to claim 1, characterized in that it comprises a thermal power unit that obtains the thermal energy by burning fossil fuel.

3. A seawater-utilizing power generation system according to claim 1, characterized in that it comprises a nuclear power unit that obtains the thermal energy by nuclear fission of uranium fuel.

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