[ automation ]
The accepted practice within large-scale production plants is for all process safety functions across the plant to be centralised and managed by an integrated control and safety system ( ICSS ). Such systems are already in place for 100 MW plants and increasingly being adopted by 20 MW plants and above . Plant-wide ICSSs act as the brain for electrolysis plants , helping to simplify operations , increase production efficiency , while reliably protecting assets . ICSSs make it possible to operate multiple , large , interconnected electrolyser units . When combined with advanced instrumentation , including pressure , temperature and water conductivity sensors , flow meters , final control elements and gas detection sensors , the ICCS software can constantly monitor performance and equipment health . Should an issue arise , the safety system can bring operations to a safe point .
The Incus ultrasonic gas leak detection system is ideally suited for monitoring well-ventilated outdoor environments .
Stable process control is essential . A well-controlled plant , which perhaps could even be autonomous , is always safer than a plant with lots of process variability , with control loops in manual status and requiring operator intervention . The challenge of managing production using electrolysis increases when power is provided directly from renewable sources , such as wind turbines . A fluctuating power supply can affect process stability and the ICSS must continue to operate the plant efficiently and safely .
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PoSHydon project in the North Sea , for example , is aimed at proving the viability of offshore green hydrogen production . The ICCS provided by Emerson manages the electrolysis unit , desalination process , variable power supply and blending with natural gas for transportation via the existing gas pipeline .
Digital twin technology , which uses a softwarebased virtual replica of the physical production assets and production processes , provides an invaluable tool to analyse various ‘ what if ’ design scenarios , such as different rectifiers or water purification systems , different balanceof-plant design improvement ideas , and others . A digital twin can also validate the optimised control and safety schemes , including advanced control models and start / stop procedures . Digital twin technology can also prove essential in the area of regulatory compliance and validation of proposed safety concept where the electrolysis facility will be integrated within existing industrial plants . Fundamentally , it enables cost-effective compliance and validation of the process control system , as well as operating procedures .
Monitoring temperature and flow
It is very important to monitor the flow of water to the electrolyser , as insufficient flow creates the risk of temperature increases that could ignite flammable gas . Typically , this application requires multiple flow measurement devices , one for control and one supporting the safety shutdown system . Another challenge can be the available space for
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