GB/T 37563-2019Safety requirements for pressurized water electrolysis system for hydrogen production (English PDF)

3.1 Hazardous and Harmful Factors

Hazardous and harmful factors refer to factors that may cause casualties, affect human health and even cause diseases.

3.3 Risk Assessment

Risk assessment includes the whole process of risk identification, risk analysis and risk evaluation.

3.4 Oxygen-enriched Atmosphere

Oxygen-enriched atmosphere refers to the environment where the volume fraction of oxygen in the air is greater than 23.5%.

4.1 Hazardous and Harmful Factors of Composition and Unit Equipment

of Hydrogen Production System The composition of the hydrogen production system is determined by factors, such as. the purpose and purity of the produced hydrogen / oxygen. A block diagram of typical hydrogen production system is shown in Appendix A.

4.2 Leakage

Hydrogen would easily leak through porous materials, assembly surfaces or sealing surfaces. After hydrogen leaks, it will rapidly diffuse, leading to continuous expansion of the leakage-contaminated area, and the diffusion process is invisible to the naked eye.

4.3 Fire Disasters and Explosions

The condition that causes hydrogen to catch fire or to explode is that the mixture of hydrogen and air or oxygen reaches the flammable or explosive limit, and there is an effective ignition source.

4.4 Suffocation

Hydrogen is a simple suffocating gas. At its high concentration, the oxygen partial pressure in the air decreases and causes hypoxic suffocation.

4.5 Electric Shock

In the hydrogen production system, equipment or facilities that might cause personal electric shocks include. water electrolyzers, rectifier transformers, rectifier cabinets, electrical cabinets, motors and power transmission copper bars, etc. During the operation and maintenance of the equipment, there is a danger of electric shock for the operating personnel.

4.6 Thermal Injury

In the hydrogen generation system, the operating temperature range of the water electrolyzer and some of its auxiliary equipment is 60 °C ~ 90 °C. The operating temperature of the deoxygenation catalyst bed of the hydrogen purifier may reach 150 °C; the regeneration temperature of the drying bed (temperature-swing adsorption) of the hydrogen purifier may reach 350 °C; if human body directly contacts the surface of the equipment, it will lead to thermal injury.

4.7 Mechanical Injury

Mechanical Injury of the hydrogen production system mainly refers to the injury caused by the direct contact of the moving parts of the mechanical equipment with the human body.

6.1 General Requirements

6.1.1 The design and installation of the hydrogen production system shall consider the influence of the environmental conditions (such as. ambient temperature, ambient humidity, altitude and seismic fortification intensity, etc.) of the user's site on the safe operation of the equipment.

6.2 Installation Location of Hydrogen Production System

6.2.1 The fire hazard category of the hydrogen production system shall be "A"; the preparation of safety facilities on the installation site shall comply with the stipulations of GB 50177.

6.2.2 Forbidden areas shall be set up in the hydrogen production system and its surrounding areas; irrelevant persons are prohibited from entering.

6.2.5 The hydrogen production site should set up emergency lightings.

6.2.6 The hydrogen production site shall set up safety signs that comply with the stipulations of GB 2894.

7.1 General Requirements

7.1.1 The design, manufacturing, installation and acceptance inspection of the oxygen recovery equipment, pipelines and accessories of the hydrogen production system shall comply with the stipulations of GB 50177 and GB/T 19774.

7.1.4 The arrangement of equipment and pipelines shall make it convenient for operation and maintenance; in case of an emergency, it shall be convenient for the evacuation of personnel.

7.1.5 The condensed water in the hydrogen equipment and pipelines shall be drained to the outdoors through the drainage water seal.

7.1.6 Preventive measures shall be taken for the stress and displacement caused by expansion and contraction of the equipment and pipelines.

7.1.7 The degreasing of equipment, pipelines and their valves and accessories in contact with oxygen shall comply with the stipulations of GB 50030 and HG 20202.

7.1.10 All rotating equipment shall be equipped with protective covers, or other protective measures shall be taken.

7.1.11 For equipment with a high noise, control measures, such as. sound insulation, noise elimination and vibration reduction, shall be adopted.

7.1.12 Equipment and valves shall be uniformly numbered; the safety signs for pipelines shall comply with the stipulations of GB 7231.

7.2 Single Equipment

7.2.1 Water electrolyzer

The performance parameters and the structure of water electrolyzer shall be based on the basic requirements of reducing unit hydrogen power consumption, reducing manufacturing costs and extending service life.

7.2.2 Pressure vessel

The pressure vessel of the hydrogen production system is mainly used for gas-liquid separation, cooling, heating and storage. The material, design, manufacturing, inspection and acceptance inspection of pressure vessels shall comply with the stipulations of TSG 21, GB/T 150 and GB/T 151.

7.2.3 Hydrogen purifier

The hydrogen purifier shall take thermal insulation measures. The inlet of the hydrogen purifier should be equipped with a flow detection instrument. The operations (temperature control and valve switching, etc.) of the hydrogen purification process should adopt automatic control devices.

7.2.6 Pressure relief device

Safety valve shall be a fully-enclosed type. It may only be used after being lead-sealed with qualification in calibration. The safety valve shall be vertically installed near the equipment being protected; the installation location shall make it convenient for inspection and maintenance.

7.2.7 Flame arrester

The hydrogen vent pipeline shall be equipped with a flame arrester. The setting of the flame arrester shall comply with the relevant stipulations of GB 50177.

7.3 Pipelines and Accessories

7.3.1 The design and installation of pipelines and accessories of the hydrogen production system shall comply with the relevant stipulations of GB/T 19774.

7.3.5 After the installation of the hydrogen / oxygen pipelines, strength test, air-tightness test and leakage test shall be conducted. This type of tests shall be performed in accordance with GB 50177 and GB 50030.

7.3.6 The purging of the hydrogen / oxygen pipelines that are qualified in the leakage test shall comply with the relevant stipulations of GB 50177 and GB 50030. When using nitrogen for purging, measures shall be taken to prevent from suffocation.

8.1 General Requirements

8.1.1 The classification of the hazardous area of the hydrogen production system shall comply with the stipulations of GB 50177 and GB 50058.

8.2 DC Power Supply

8.2.1 Each water electrolyzer shall be separately equipped with a DC power supply; high-frequency switch rectifier, thyristor rectifier or diode rectifier should be adopted.

8.2.2 The DC power supply shall have the functions of voltage regulation and automatic current stabilization; it shall be equipped with an overcurrent protection device, which will automatically stop when it exceeds a predetermined value.

8.2.3 The high-voltage rectifier transformer equipped with the DC power supply shall be located in a separate transformer chamber.

8.2.4 An emergency power-off button of the DC power supply shall be installed in the electrolysis room. This button should be located in a place that is convenient for operation.

8.3 Electro-heating Elements

8.3.1 The technical requirements of metallic tube-type electro-heating elements shall comply with the stipulations of JB/T 2379.

8.4 Grounding

8.4.1 The metal shell, metal pipeline, metal base or frame of the hydrogen production system shall be grounded. The grounding shall comply with the stipulations of GB 50177 and GB 50057.

8.4.4 The grounding of electrical installations shall be connected to the grounding trunk through a separate grounding wire; no series connection is allowed.

8.4.5 All lightning protection and static protection grounding devices shall be regularly tested for the grounding resistance at least once a year.

8.5 Hydrogen Leakage Detection

8.5.1 The hydrogen production system shall be equipped with a fixed hydrogen detection alarm, and its technical performance shall comply with the stipulations of GB 12358 and GB 16808. The detector of the fixed hydrogen detection alarm shall be installed in a place where hydrogen is easy to leak and accumulate.

8.5.2 The hydrogen production system shall be equipped with a portable hydrogen detection alarm.

8.5.3 The fixed hydrogen detection alarm and the portable hydrogen detection alarm shall be regularly calibrated.

8.5.4 The hydrogen detection alarm shall normally work during equipment maintenance.

8.7 Automatic Control System

8.7.1 The automatic control system of the hydrogen production system shall conduct centralized monitoring and automatic adjustment of the main process parameters.

When the equipment fails, it shall promptly give an alarm, shut down the machine, and properly handle it.

8.7.2 The measuring range and accuracy grade of the meter shall satisfy the requirements for use. The meters in contact with oxygen shall be grease-free.

8.7.5 Before new equipment is put into production, or, after overhauling, the automatic control system shall receive tests and simulation tests, and comply with the following requirements. […]

9.1 Preparation before First Actuation

9.1.1 It shall be confirmed that the various certificates and technical documents provided by the manufacturer are complete and correct. These materials shall at least include the following content.

9.1.2 The hydrogen production system shall be installed on site.

9.1.3 Before actuation, a comprehensive safety inspection shall be carried out; the identified problems shall be rectified one by one.

9.1.4 The on-site production environment shall comply with the design requirements; the various production auxiliary systems shall reach the conditions for actuation.

9.2 Equipment Operation

9.2.1 The preparation before daily actuation shall comply with the stipulations of 9.1.4 and 9.1.5. If the system is actuated from the pressure-holding state, then, no replacement is required.

9.2.2 Before actuation, it shall be ensured that there is no debris on the water electrolyzer, so as to prevent short circuit.

9.2.3 The hydrogen production system shall be actuated and unactuated strictly in accordance with the operating procedures.

9.3 Equipment Maintenance

9.3.1 The maintenance and overhauling operations of the hydrogen production system shall work out an operational scheme, which may be organized and implemented after receiving approval.

9.3.2 The maintenance and overhauling operations shall execute the lockout / tagout procedures.

9.3.7 When the safety facilities are being maintained, and there are no other alternative measures, the operation of the protected equipment shall be stopped.

9.3.8 The records of maintenance and overhauling operations shall be kept for at least 3 years.

9.3.9 Equipment removal work shall be carried out in weather without thunder or lightning. During the dismantling of the equipment, the hydrogen content in the air shall be continuously monitored; once it exceeds 0.4% (volume fraction), the dismantling work shall be immediately stopped. […]