Hydrogen has been adopted as a key element in a renewable energy pathway and has been used in industrial processes for decades. However, not all hydrogen production methods are green, which means the method of production is crucial if hydrogen is to be utilised as part of a green energy pathway.
Green hydrogen can be produced by splitting the elements of hydrogen and oxygen from water via electrolysis that has been powered by wind or solar energy. Four types of electrolyser technology have been introduced - Proton Exchange Membrane Electrolysis (PEM), Solid Oxide Electrolysis (SOEC), Anion Exchange Membrane Electrolysis (AEM), and Alkaline Water Electrolysis (AWE). Globally, the industry favours AWE for the largest green hydrogen projects that are currently underway or have just been announced (at the time of writing).
About AWE
Alkaline Water Electrolysis is the oldest, most industrially advanced and cheapest water electrolysis technology. The process uses a highly corrosive 30-40% potassium hydroxide (KOH) alkali solution as the electrolyte feedstock. The electrolyte is under constant circulation within the electrolyser. It will corrode the electrolyser components and the process pipework if left uncoated, causing the highly caustic solution that could become contaminated with very fine particles of both the electrolyser and the pipework which forms the system itself.
With a substance so caustic, corrosion isn’t just a consideration for wear and tear but can also lead to stress corrosion cracking which in turn can lead to catastrophic failure of equipment.
Benefits of ETFE fluoropolymer coating
At AFT Fluorotec, we have worked with a number of process system and filter OEMs to develop a reinforced ETFE fluoropolymer coating. The coating is applied to the internal surfaces of the electrolyte solution system - the process pipework, vessels, filter housings etc - for KOH process pipework systems. Our unique reinforced fluoropolymer coating is designed to withstand KOH solutions at elevated temperatures – H2 or O2 saturated. It is resistant to KOH solutions in AWE process system pressures of 10 bar, temperatures up to 100oC and KOH concentrations over 50%.
AFT Fluorotec coatings can offer /coating-surface-preparation/ tailored to requirements which can be applied at thicknesses from 0.8mm to 2mm. The addition of an ETFE reinforced coating ensures the safety and lifespan of expensive equipment and allows filtration systems to operate optimally.
AFT is proud to have applied its coatings and technology to AWE hydrogen production projects all over Europe and the Middle East.
