SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a megawatt power station.
In order to achieve the purpose, the utility model provides the following scheme:
a megawatt power plant comprising:
a hydrogen production unit comprising: an input electric conditioning subunit, an input water conditioning subunit, an electrolysis bath subunit and a hydrogen purification subunit; the input electric conditioning subunit is used for conditioning the electric energy input into the hydrogen production unit, and the output end of the input electric conditioning subunit is electrically connected with the electrolytic bath subunit; the input end of the input water conditioning subunit is a tap water interface, and the output end of the input water conditioning subunit is connected with the electrolytic bath subunit; the electrolytic cell subunit consists of a plurality of proton exchange membranes connected in series and in parallel, and the output end of the electrolytic cell subunit is connected with the hydrogen purification subunit; the electric energy source of the input electric conditioning subunit is the off-peak electricity of the power grid;
a hydrogen storage unit comprising: a first hydrogen conditioning subunit and a gas storage subunit; the input end of the first hydrogen conditioning subunit is connected with the electrolytic bath, and the output end of the first hydrogen conditioning subunit is connected with the gas storage subunit;
a power generation unit comprising: a second hydrogen conditioning subunit, a fuel cell subunit and an output electric conditioning subunit; the input end of the second hydrogen conditioning subunit is connected with the gas storage subunit, and the output end of the second hydrogen conditioning subunit is connected with the fuel cell subunit; the fuel cell subunit consists of a plurality of fuel cell groups connected in series and parallel; the input end of the output electric conditioning subunit is electrically connected with the fuel cell subunit, and the output end of the output electric conditioning subunit is connected with a power grid;
a hydrothermal unit comprising: the heat exchange subunit and the heat storage and supply subunit; the heat exchange sub-unit is used for cooling the hydrogen production unit; the heat storage and supply subunit is used for storing and utilizing the heat acquired by the heat exchange subunit.
Optionally, the electric energy source of the input electric conditioning subunit further includes a renewable energy source.
Optionally, the input electrical conditioning subunit includes an AC/DC rectifying device and a transformer; the AC/DC rectifying device is used for converting alternating current input by a power grid into direct current, and the transformer is used for reducing voltage of the direct current.
Optionally, the input water conditioning subunit comprises: the water purification device is used for purifying water in the raw material water tank.
Optionally, the hydrogen purification sub-unit comprises a hydrogen-oxygen separator for separating hydrogen and oxygen electrolyzed by the electrolyzer sub-unit, and a gas cooler for cooling hydrogen and oxygen.
Optionally, the first hydrogen conditioning subunit includes a gas-water separator, a deoxygenator, a dryer, a medium-pressure buffer tank, and a hydrogen compressor, where the gas-water separator is configured to separate moisture from hydrogen output by the hydrogen purification subunit, the deoxygenator is configured to remove oxygen from the hydrogen, the dryer is configured to dry the hydrogen, the hydrogen compressor is configured to compress the hydrogen, and the medium-pressure buffer tank and the hydrogen compressor are configured to compress the hydrogen.
Optionally, the second hydrogen conditioning subunit includes a hydrogen pressure reducing valve group, a hydrogen backflow fan and an air compressor, and hydrogen sequentially enters the fuel cell subunit through the hydrogen pressure reducing valve group and the hydrogen backflow fan.
Optionally, the output electrical conditioning subunit includes an AC/DC converter and a boost converter, the AC/DC converter is configured to convert the direct current output by the fuel cell subunit into an alternating current, the boost converter is configured to boost the alternating current, and the electric energy output by the fuel cell subunit is grid-connected after passing through the AC/DC converter and the boost converter.
Optionally, the heat exchange subunit is a water-cooled heat dissipation system, the heat storage and supply subunit includes a heat storage water tank and a heat supply pump, and part of hot water in the heat exchange subunit is stored in the heat storage water tank to supply hot water for life and hot water for heating facilities.
According to the specific embodiment provided by the utility model, the utility model discloses the following technical effects: the megawatt-level power station provided by the utility model adopts off-peak electricity or a renewable power supply to supply power, adopts a proton exchange membrane electrolytic cell to realize hydrogen production by water electrolysis, adopts a proton exchange membrane fuel cell to realize hydrogen power generation, and is finally connected to the grid. The whole station of the power station realizes the energy circulation of electricity-hydrogen-electricity, and realizes the functions of peak clipping and valley filling of a power grid, long-term consumption of renewable energy, combined heat and power supply and the like.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
The megawatt power station provided by the embodiment comprises: hydrogen production unit 1, hydrogen storage unit 2, power generation unit 3, and hydrothermal unit 4. The four units are specifically described as follows:
1) hydrogen production unit 1: the device is used for electrolyzing raw material water into hydrogen and oxygen, and is composed of an input electric conditioning subunit 11, an input water conditioning subunit 12, an electrolytic bath subunit 13 and a hydrogen purification subunit 14, and is shown in figure 1. The input end of the input electric conditioning subunit 11 is connected with a power grid, and the output end is electrically connected with the electrolytic bath subunit 13; the input end of the input water conditioning subunit 12 is a tap water interface, and the output end is connected with the electrolytic bath subunit 13; the output of the electrolyzer subunit 13 is connected to a hydrogen purification subunit 14. The method comprises the following specific steps:
input electronic conditioning subunit 11: the electrolytic cell is composed of an AC/DC rectifying device 111 and a transformer 112, and is used for converting input alternating current into direct current, rectifying the transformed current and voltage, and inputting the current and voltage into the electrolytic cell. The electric energy source of the input electric conditioning subunit 11 is renewable energy or off-peak electricity of a power grid, so as to realize peak shaving of the power grid and utilization of the renewable energy.
In this example, the rated current of the hydrogen production apparatus by water electrolysis was 6600A (cell current 3300A), and the cell voltage was about 102V.
Input water conditioning subunit 12: consists of a pure water device 121 and a raw material water tank 122. The input end of the input water conditioning subunit 12 is a tap water interface, and the output end is connected with the electrolytic cell. Used for inputting raw material water into an electrolytic bath for electrolysis. On the one hand, since high-purity water is the "raw material" of the hydrogen (oxygen) production process by water electrolysis, and on the other hand, since hydrogen and oxygen carry a small amount of water away from the system, it is necessary to continuously replenish the system with raw material water. Moreover, the stability of the liquid level and concentration of the electrolyte can be maintained by continuously supplementing raw material water for the system. The raw material water may be supplied from both sides of hydrogen and oxygen, and this embodiment adopts a method of supplying from both sides.
Electrolyzer subunit 13: the electrolytic cell is the most important part in the hydrogen production unit 1 and is composed of a plurality of proton exchange membranes 131 connected in series and in parallel. The input end of the electrolytic bath subunit 13 is connected with the input electric conditioning subunit 11 and the input water conditioning subunit 12, and the output end is connected with the hydrogen purification subunit 14. The water electrolysis hydrogen (oxygen) production adopts pure water solution as electrolyte, and water is electrolyzed into hydrogen and oxygen.
Hydrogen purification subunit 14: consists of a hydrogen-oxygen separator 141, a hydrogen-oxygen comprehensive tower 142 and a gas cooler 143, the input end of the hydrogen-oxygen comprehensive tower is connected with the electrolytic bath subunit 13, and the output end of the hydrogen-oxygen comprehensive tower is connected with the hydrogen storage unit 2, and the hydrogen-oxygen comprehensive tower is used for separating and cooling the electrolyzed hydrogen and oxygen. Hydrogen gas is split off from the cathode side of the electrolysis cell and separated from the electrolyte in a hydrogen separator by means of circulation of the electrolyte and the difference in gas-liquid specific gravity to form product gas.
2) Hydrogen storage unit 2: for storing the electrolyzed hydrogen product, referring to fig. 2, the hydrogen storage unit 2 is composed of a first hydrogen conditioning subunit 21 and a gas storage subunit 22, and the details are as follows:
the first hydrogen conditioning subunit 21 is composed of a gas-water separator 221, a deoxygenator 222, a dryer 223, a medium-pressure buffer tank 224 and a hydrogen compressor 225. The electrolyzed hydrogen is connected with a gas-water separator 221 through a pipeline, the gas-water separator 221 separates the moisture in the hydrogen, then the hydrogen enters a deoxygenator 222 to remove the redundant oxygen, then enters a drier 223 to be further dried, and finally is compressed by a medium-pressure buffer tank 224 and a hydrogen compressor 225.
The gas storage subunit 22 is operated by high pressureThe buffer tank group 221. The gas storage sub-unit 22 is connected at its input to a hydrogen compressor 225 and at its output to the second hydrogen conditioning sub-unit 31 of the power generation unit 3. In this example, the number of the 4 stages is 2.25m3The high-pressure buffer tank group 221 forms a high-pressure buffer tank group 221 for storing the finished product hydrogen.
3) The power generation unit 3: referring to fig. 3, the power generation unit 3 includes a second hydrogen conditioning subunit 31, a fuel cell subunit 32, and an output electrical conditioning subunit 33; the input end of the second hydrogen conditioning subunit 31 is connected with the gas storage subunit 22, and the output end is connected with the fuel cell subunit 32; the input end of the output electric conditioning subunit 33 is electrically connected with the fuel cell subunit 32, and the output end is connected with the power grid. The method comprises the following specific steps:
the second hydrogen conditioning subunit 31 is composed of a hydrogen pressure reducing valve set 311, a hydrogen reflux fan 312 and an air compressor 313, the hydrogen source is a hydrogen high-pressure buffer tank, and the compressed finished hydrogen is reduced in pressure by the hydrogen pressure reducing valve set 311 and is delivered into the fuel cell stack by the hydrogen reflux fan 312 for power generation.
The fuel cell sub-unit 32 is an important component of the power generation unit 3, and is composed of a plurality of fuel cell stacks 321 connected in series and parallel. The input end of the fuel cell subunit 32 is connected with the second hydrogen conditioning subunit 31, and the output water is directly recovered. Hydrogen and air enter the stack through corresponding inlets in the fuel cell and are distributed to the bipolar plates of each single cell through the stack gas main channel. The hydrogen is uniformly distributed to the anode of the cell through the bipolar plate flow guiding field, reaches the proton exchange membrane through the diffusion layer on the electrode, is dissociated into hydrogen ions, namely protons, under the action of the anode catalyst, and releases electrons. At the other end of the fuel cell, air passes through the gas-conducting channels on the bipolar plate to the cathode of the cell, through the diffusion layer on the electrode to the proton exchange membrane. Meanwhile, hydrogen ions generated by proton exchange between the hydrogen ions and the electrolyte membrane reach the cathode, and electrons also reach the cathode through an external circuit. Under the action of the cathode catalyst (platinum), oxygen reacts with hydrogen ions and electrons to produce water.
The output electric conditioning subunit 33 is composed of an AC/DC converter 331 and a dry boost transformer 332. The input end of the output electric conditioning subunit 33 is connected with the fuel cell to receive the electric energy of the fuel cell, and the output end is connected with the power grid to connect the electric energy generated by the fuel cell to the grid. Each power generation unit 3 is correspondingly provided with a set of inverter groups, the direct current output by the power generation unit 3 is inverted into alternating current respectively, and then the alternating current is connected with the low-voltage side of the step-up transformer 112, is stepped up to 10kV through step-up transformer, and is connected to the grid for power generation.
4) Hydrothermal unit 4: referring to fig. 4, the hydrothermal unit 4 includes a heat exchange subunit 41 and a heat storage and supply subunit 42. Wherein, the heat exchange subunit 41 is used for cooling the hydrogen production unit 1; the heat storage and supply subunit 42 is used for storing and utilizing the heat obtained by the heat exchange subunit 41. The method comprises the following specific steps:
the heat exchange subunit 41 is composed of a water chiller 411, a water chiller 412 and a cooling tower 413. Since the electrolysis of water is an endothermic reaction, the hydrogen production process must be powered, but the electrolysis consumes more power than the theoretical endothermic amount of the water electrolysis. The excess is mainly carried away by cooling water to maintain a normal temperature of the electrolytic reaction zone. In this embodiment, the operating temperature should not exceed 90 ℃.
As an embodiment of the heat exchange subunit 41 in the present embodiment, a specific form of the heat exchange subunit 41 may be as follows: taking the cooling of the power generation unit 3 with four groups of fuel cells as an example, a deionized water closed circulation mode is adopted, water generated by the pure water device 121 is led to the intermediate water tank (provided with heat tracing) through a pipeline and a valve, the water is led to the intermediate water tank through a pipeline and 2 cooling water circulating pumps are connected with hot end inlets of the two platen heat exchangers, plate heat exchange end outlets are connected with a cooling water inlet header pipe through pipelines, the plate heat exchange end outlets are divided into 6 paths of sub-pipes which are respectively connected with cooling water inlets of the power generation unit 3 through pipelines, wherein 4 paths of sub-pipes are connected with cooling water inlets of the fuel cells through pipelines, and cooling water outlets of the fuel cells are gathered through pipelines and flow back to the intermediate water tank.
The heat storage and supply subunit 42 is composed of a heat storage water tank 421, a heat supply pump 422 and a heating facility 423, wherein part of hot water is stored in the heat storage water tank 421 for domestic hot water, and part of hot water flows through the heating facility 423 for heating in winter.
The working principle of the megawatt power station provided by the utility model is as follows:
referring to fig. 5 and 6, raw material water is injected into a raw material water tank, then enters a cooler through a pipeline, enters an electrolytic cell for electrolysis after being filtered, and the power supply of the electrolytic cell is electrolyzed after being transformed by an external power supply through a transformer and alternating current-direct current conversion. The oxygen is separated by an oxygen separator and is exhausted after passing through an oxygen comprehensive tower, a gas cooler and a gas-water separator. Separating hydrogen from a hydrogen separator, cooling the hydrogen by a hydrogen comprehensive tower and a gas cooler, removing water by a gas-water separator, removing redundant oxygen by a deoxygenator, drying the hydrogen by a cooling condenser and a dryer, and finally pressurizing the hydrogen by a medium-pressure buffer tank and a compressor and then entering a high-pressure buffer tank. The hydrogen in the high-pressure buffer tank is decompressed by a hydrogen decompression valve bank and then enters a fuel cell, meanwhile, air is input into the fuel cell by an air compressor, and water generated after chemical reaction enters a hydrogen production raw material water tank through a pipeline. And the redundant hydrogen is input into the fuel cell again by a hydrogen reflux fan. Meanwhile, the generated electric energy is converted into alternating current through an inverter and is converted into 10kV alternating current through a dry-type step-up transformer to be connected to the grid for power generation. Referring to fig. 7 and 8, raw material water enters a cooling tower through a softener for cooling, enters a water chiller through a pipeline, enters cooling return water after being cooled, and the water chiller exchanges heat with a cooling condenser and a regenerative cooler. The cooling tower is connected with cooling water inlet and outlet, and the water cooler guides water into cooling water return water. The cooling water enters and exits to exchange heat with the plate heat exchanger, the plate heat exchanger enters the hot water heat exchanger through the pipeline, the hot water heat exchanger exchanges heat with the heat storage water tank, and the water in the heat storage water tank sends hot water into a heating facility through the heat supply pump.
The megawatt-level power station provided by the utility model adopts the power grid off-peak electricity to prepare hydrogen for storage, adopts the stored hydrogen to generate and connect the grid during the peak power consumption, realizes the peak clipping and valley filling of the power grid, and simultaneously adopts the renewable power supply to supply power to prepare the hydrogen, realizes the long-term consumption of renewable energy, avoids the impact on the power grid during the grid connection of the fluctuating new energy, and improves the safety and stability of the system. In addition, the utility model uses the waste heat generated in the hydrogen production process for domestic water and heating, thereby realizing combined heat and power supply.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the utility model.