In the pursuit of cleaner and sustainable energy solutions, hydrogen has emerged as a promising fuel. Sofis’ primary objective is to ensure safety in the hydrogen economy given the inherent dangers it presents, and one of these applications identified is the hydrogen offloading process. A Sofis customer recently implemented a valve interlocking solution for a green hydrogen tube trailer (TT) refueling panel, ensuring correct and safe operating procedures while adhering to the highest safety standards.
Hydrogen tube trailers operate at different pressures
Our customer, a forward-thinking organization in the renewable energy sector, embarked on establishing an on-site hydrogen refueling station at their facility. The project involved the installation of multiple panels – compact units designed for vehicle personnel and operators to refuel TTs at their premises. These TTs have different operating pressures, ranging up to 300 bar, requiring a careful selection of the correct pressure for each trailer.
Ensuring correct and safe operation
To ensure precise and safe refueling operations, our team proposed the integration of valve interlocks with the panels. These interlocks are strategically fitted on respective isolation ball valves, enforcing a sequential and foolproof operating procedure. This means it is not possible to make a mistake and the compressor cannot begin operation to begin filling the tube trailer until the corresponding pressure line is open. Due to the trapped key system, it is only possible to open one pressure line at a time.
Addressing hydrogen safety concerns
The safe handling of hydrogen is of paramount importance due to its inherent properties. Hydrogen is highly flammable and at high pressure is susceptible to spontaneous combustion. Therefore, adherence to established safety standards is crucial to mitigate hazards during hydrogen offloading. Sofis valve interlocking solutions align with industry standards and guidelines for the safe offloading of hydrogen. The valve interlocks act as physical barriers, preventing inadvertent or unauthorized access to critical valves during the refueling process. This significantly reduces the likelihood of operator error and the potential for dangerous situations.
Integration of electronic valve interlock key cabinet
In addition to installing valve interlocks, we incorporated a simple electronic cabinet into the system for an extra layer of safety assurance. This cabinet serves as the final stage of the operating sequence. Vehicle personnel must follow the prescribed steps, and only upon completion, they can insert a key into the electronic cabinet. The electronic cabinet then sends a signal, indicating that the conditions for safe offloading have been met.
The implementation of our valve interlocks and electronic cabinet has yielded desirable outcomes for our customers’ green hydrogen refueling project. Valve interlocks enhance safety by ensuring that correct and safe operating procedures are diligently followed, reducing the risk of accidents and potential hydrogen-related incidents. By adhering to industry safety standards for hydrogen offloading, our solution also reinforces our customers’ commitment to safety and regulatory compliance. In particular the Pipeline Safety Regulations 1996 – specifically states “Interlock arrangements may be provided as safety systems, particularly where they prevent inadvertent operation.”. Finally, operator confidence is increased significantly. The comprehensive safety measures instill confidence in vehicle personnel and operators, enabling them to carry out their duties with peace of mind.