Pure water hydrogen generatorBy electrolyzing ultrapure water (with a resistivity of ≥ 10M Ω· cm), high-purity hydrogen gas (with a rated hydrogen production rate of usually 100-1000mL/min) is produced, which is widely used in laboratory analysis, industrial auxiliary gas supply and other scenarios. Overpressure shutdown "is triggered by system pressure exceeding the safety threshold (usually 0.8-1.2MPa), while" insufficient hydrogen production "is caused by a decrease in electrolysis efficiency. It needs to be prevented through" precise pressure control electrolysis system maintenance raw water optimization real-time monitoring "to ensure continuous and stable operation of the equipment.

　　1、 Pressure control optimization: the core to avoid overpressure shutdown

Through multi-level pressure regulation and safety protection, ensure that the system pressure is stable within a safe range:

Dual stage pressure valve linkage control: Connect a "pilot pressure valve+back pressure valve" in series at the hydrogen output end - the pilot pressure valve sets the working pressure (such as 0.4MPa, adapted to the gas chromatography carrier gas demand), and adjusts the hydrogen output in real time; The back pressure valve is set with a safety threshold (such as 1.0MPa, which is 0.2MPa lower than the equipment shutdown pressure). When the pilot valve fails and the pressure rises, the back pressure valve automatically releases pressure (with a release rate ≥ 500mL/min) to avoid the pressure reaching the shutdown threshold. Regularly (once a month) calibrate the pressure valve to ensure an error of ≤ ± 0.02MPa.

Flow matching and buffering design: Based on the real-time hydrogen consumption of downstream hydrogen consuming equipment (such as gas chromatography instantaneous hydrogen consumption of 50mL/min), the hydrogen production rate is adjusted through the device's built-in flow sensor (accuracy ± 2%) to avoid pressure accumulation caused by "hydrogen production>hydrogen consumption"; Install a buffer tank (with a capacity ≥ 10 minutes of hydrogen production by the equipment) in the hydrogen storage chamber to balance pressure fluctuations (such as when using hydrogen equipment to start and stop, the buffer tank can absorb pressure shocks, with pressure fluctuations ≤ 0.05MPa) and reduce the risk of overpressure.

　　2、 Maintenance of electrolysis system: key to ensuring hydrogen production efficiency

The state of the electrolytic cell and electrodes directly affects the hydrogen production, and regular maintenance is required to avoid performance degradation:

Cleaning and activation of electrolytic cell: Disassemble the electrolytic cell every 3-6 months, soak the electrode plate (titanium based coated electrode) in a 5% dilute sulfuric acid solution (temperature 25-30 ℃) for 30 minutes, remove surface precipitated hydroxide impurities (such as NaOH crystals), and rinse with ultrapure water until neutral; If the electrode coating peels off (such as the titanium based coating exposing the substrate), the electrode plate should be replaced in a timely manner (to avoid a decrease of more than 30% in electrolysis efficiency) to ensure stable hydrogen production.

Power and membrane module inspection: Check the output voltage (usually 1.8-2.2V) and current (matched according to the hydrogen production rate, such as 1.5A for 100mL/min hydrogen production) of the electrolytic power supply. If the voltage rises abnormally (over 2.5V), it may be due to aging of the membrane module (decreased proton exchange membrane permeability), and the membrane module needs to be replaced (it is recommended to replace it every 1-2 years); The power module is regularly (quarterly) dusted to avoid fluctuations in output current caused by poor heat dissipation, which can affect hydrogen production.

　　3、 Raw water management: the foundation for preventing insufficient hydrogen production

Insufficient purity and dosage of pure water can directly lead to a decrease in electrolysis efficiency, and strict control is required

Purity control of raw water: Only ultrapure water (resistivity ≥ 10M Ω· cm, total organic carbon ≤ 5ppb) is used to avoid scaling of ions (such as Ca ² ⁺, Cl ⁻) contained in tap water or low purity water on the electrode surface, which can increase electrolytic resistance (reduce hydrogen production by 10% -20%); Install a 0.22 μ m filter membrane at the inlet to filter out particles in the water and prevent blockage of the electrolytic cell flow channel.

Water level and replenishment control: During equipment operation, maintain the water level in the water tank at 60% -80% (monitored in real-time through a liquid level sensor). When the water level drops below 50%, automatically shut down for replenishment (to avoid dry burning and damage to the electrolytic cell caused by empty burning); When replenishing water, the "slow charging mode" (replenishment rate ≤ 100mL/min) is used to prevent the water flow in the electrolytic cell from being disturbed due to a sudden rise in water level, which affects the stability of hydrogen production.

　　4、 Status monitoring and warning: early avoidance of fault risks

By real-time monitoring and warning, abnormalities can be detected and dealt with in a timely manner:

Real time parameter monitoring: Enable the intelligent monitoring function of the device to display real-time parameters such as pressure (accuracy ± 0.01MPa), hydrogen production (accuracy ± 5mL/min), water temperature (electrolytic cell temperature ≤ 40 ℃), etc. When the pressure exceeds 0.9MPa or the hydrogen production is below 90% of the rated value, sound and light alarms will be triggered (alarm response time ≤ 1 second) to remind operators to intervene.

Regular performance verification: Use a soap film flowmeter to calibrate the hydrogen production rate every quarter (for equipment rated at 100mL/min, the measured value should be ≥ 95mL/min). If the deviation exceeds 5%, the electrolysis system or pressure control link needs to be checked; Simultaneously test the purity of hydrogen gas (analyzed by gas chromatography, purity should be ≥ 99.999%). The decrease in purity may be due to air leakage (such as poor sealing of pipeline interfaces). It is necessary to use soapy water to detect the leakage point and seal it to avoid impurities affecting hydrogen production efficiency.

Through the above scheme, the frequency of "overpressure shutdown" of the pure water hydrogen generator can be reduced by more than 80%, the hydrogen production can be stabilized at over 95% of the rated value, adapted to the continuous hydrogen demand of downstream equipment, and the service life of the equipment can be extended (from 2-3 years to 3-5 years), reducing maintenance costs.