Detailed description of hydrogen production system module composition and scheme:
(1) PEM electrolyzer
The system adopts PEM electrolyzer with a hydrogen production capacity of 10 Nm3/h. The electrolyzer is assembled by pressing membrane electrodes, separators, gas diffusion layers, and other components. The electrolyzer has inlet pipes, hydrogen and oxygen liquid outlet pipes; Pure water decomposes under the action of direct current in the electrolyzer, producing hydrogen and oxygen on the electrode surface, which enter the gas-liquid separation system through their respective channels.
(2) Gas water separation module and purification module
The mixture of hydrogen gas and pure water electrolyzed from the electrolyzer is introduced into the hydrogen steam water separator, where it is cooled by heat exchange through an internal heat exchanger. Under the action of gravity, gas-liquid separation is carried out, and the separated hydrogen gas is further washed and cooled by the hydrogen washing cooler at the upper part of the gas-liquid separator, thereby minimizing the water content in the gas. Hydrogen can achieve the predetermined purity after being separated into gas and water through a scrubber and a steam water separator. The purification system is designed in accordance with the local standard "Safety Technical Specification for Hydrogen Production and Hydrogenation Integrated Station" DB44/T 2440-2023 in Guangdong Province. According to standard requirements, the catalyst device is designed to remove trace amounts of oxygen from hydrogen gas, improve hydrogen purity, and achieve pure hydrogen grade. After drying and purification, hydrogen meets the hydrogen standard specified in GB/T 3634.2.
(3) Supply system module
This module is mainly used to supply deionized water to the electrolyzer. After passing through the water purification and filtration system, the external water source enters the water tank. The water in the water tank is supplied to the electrolyzer through a pipeline, and the other can be injected into the hydrogen (oxygen) scrubber section above the hydrogen (oxygen) separator through a water pump to purify the hydrogen gas.
(4) Cooling water circulation system module
The cooling water from the cooling water main pipeline enters the equipment in two ways, one of which is used to control the temperature of deionized water and maintain the working temperature of the electrolyzer; The other route enters the hydrogen and oxygen scrubbers through ball valves to cool the gas, reduce its moisture content, and ensure that the outlet gas temperature does not exceed 40 ℃.
(5) Electronic control system module
The electronic control system consists of four parts: hydrogen production system, converter system, main control system, and monitoring system. The hydrogen production system includes an electrolysis cycle unit, a purified water filtration unit, a PSA pressure swing adsorption unit, and a hydrogen dew point detection unit. The inverter system consists of a rectifier unit, an inverter unit, a protection unit, a control unit, and a filtering unit. The main control system consists of PLC control unit, sensor input unit, execution output unit, and bus system. The monitoring system consists of industrial Ethernet and monitoring software.