Water Electrolysis Hydrogen Production System

Water Electrolysis Hydrogen Production System 2022-03-07 09:27:40

1. Water replenishment system
The raw water first enters the desalinated water preparation device, and after ultrafiltration + secondary reverse osmosis treatment, it enters the lye tank, the alkali distribution water tank and the cooling device water tank. The water that enters the lye tank and the lye water tank is prepared into lye, and the lye is pumped into the intake liquid separation device and enters the lye circulation system, thereby replenishing the lye for the lye circulation system; enters the water tank of the desalinated water cooling device The water, under the power of the circulating water pump, flows through the water-water heat exchanger and enters the multiple coolers in the gas-liquid separation device and the hydrogen purification device, and then returns to the water tank of the cooling device.

2. Lye circulation system
The electrolyte from the electrolytic cell has two paths: one is rich in hydrogen, and the other is rich in oxygen. They enter the hydrogen separator and oxygen separator in the gas-liquid separation device. After the hydrogen and oxygen are separated, the two The lye solution converges and is filtered by the lye filter, then cooled by the lye cooler, enters the lye circulation pump, pressurized by the pump, and returns to the electrolytic cell, thereby realizing the lye circulation in the hydrogen production system.

3. Electrolyzer
The lye of the lye circulation system enters the electrolyzer, and the water begins to decompose under the action of direct current, and hydrogen and oxygen are respectively generated on the cathode and anode plates of the electrolysis chamber. These hydrogen and oxygen flows out of the two ends of the electrolytic cell along with the electrolyte into the gas-liquid separation device.

The reaction equation in the electrolytic cell is as follows:
electrolysis
2H2O ======= 2 H2↑ + O2 ↑

KOH (electrolyte)

4. Gas-liquid separation device
The gas-liquid separation device is equipped with hydrogen separation scrubber, oxygen separator, hydrogen cooler, gas-water separator, lye circulation pump and other equipment. The electrolyte containing hydrogen and oxygen passes through the hydrogen and oxygen separators, and is separated from the electrolyte lye under the action of gravity. The separated oxygen is discharged to the outdoors, and the hydrogen is further washed, cooled, separated and removed in the separation device to remove liquid droplets. Then enter the hydrogen purification unit.
5. Hydrogen purification device
In the hydrogen purification device, the hydrogen is catalyzed by the catalyst to react with the residual oxygen in the hydrogen as follows: 2H2+O2=2H2O,
After cooling, adsorption, and separation, high-purity hydrogen with a purity of 99.999% is obtained.
6. Hydrogen storage equipment
The high-purity hydrogen is distributed to each hydrogen storage tank for storage after the pressure is balanced by the hydrogen manifold rack.
7. Hydrogen supply system
At present, there are mainly three methods of outbound hydrogen storage: hydrogen cylinder racks, long tube trailers, and solid hydrogen storage devices. Because solid hydrogen storage devices are rarely used in China, they are still in the research and development stage in China. Therefore, hydrogen cylinders are generally considered And long tube trailers as the main means of transportation.
The main technological process of the hydrogen supply system is as follows:
Hydrogen storage tank → hydrogen bus bar → hydrogen buffer tank → hydrogen compressor → hydrogen charging bus bar (or filling device) → hydrogen cylinder group (or long tube trailer).

8. Auxiliary system
The hydrogen production auxiliary system mainly includes: algae removal preparation, refrigeration system, compressed air system, lye storage system and suction and sweep system.