Green Hydrogen
Water is essential for the production of green hydrogen. As the market matures, crucial questions about the use of water are starting to arise. What quality is sufficient? How do we prevent corrosion and contamination?
In the production of green hydrogen, it is necessary to distinguish between three types of water:
- Ultrapure water (used as a feedstock for the electrolyser)
- Cooling water
- Raw water
The quantity of ultrapure water used for electrolysis will be different from that of raw water extracted from the environment, and the quality of ultrapure water and cooling water is also different. Therefore, we need to deal with each one separately.
Ultrapure water
Water suitable for electrolysis is commonly called ultrapure, but what is to be understood by this label?
Several parameters influence what quality water must have to be suitable for electrolysis. These include the type of electrolyser, electrode material, system design and even brand of electrolyser.
Add to this that each of the ions and molecules in water will affect the electrolyser differently. Some can increase OPEX because of corrosion or increased need for cleaning, while others can lower the electrolyser efficiency and/or irreversibly damage and degrade the electrolyser.
With so many variables and effects, it is no surprise that water treatment is often tailored to the specific project, making it very difficult to come up with a unified standard for water quality for all electrolysers.
One strategy that electrolyser manufacturers can follow to simplify the issue is to set the requirements for conductivity sufficiently low to ensure that the concentration levels of problematic ions and molecules will in all certainty be below the electrolyser requirements. A good starting point can be <1 µS/cm for standard alkaline electrolysers, and <0.1 µS/cm for PEM electrolysers and alkaline electrolysers relying on advanced electrodes. However, it is worthwhile to remember two things: firstly, water treatment constitutes a relatively minor part of the total CAPEX of a hydrogen plant, and secondly, no electrolyser was ever damaged by using water that was too clean. Ensuring high quality and reliability in the water treatment may thus be the best investment to be made for an electrolyser system.
Characteristics of FRP, dual laminate plastics and thermoplastic lined FRP Products
FRP is known for its mechanical strength and a popular choice when it comes to corrosion resistance. Furthermore is FRP light weight, has excellent temperature-resistant properties, offers thermal insulation and can be formed in complex shapes. FRP products are easy to repair and hardly require any maintenance.
Equipment made with dual laminate FRP, using a thermoplastic or Fluoropolymer inner liner and a fiberglass composite exterior, combine the advantages of thermoplastic with reinforced thermoset plastics to produce a product with top quality corrosion resistance, mechanical performance and minimum contamination.
FRP, dual laminate plastics and thermoplastic lined FRP Products
The majority of FRP products, such as storage tanks are cylindrical in shape. Yet the benefit of working with FRP is the endless possibilities as regards thickness, capacity for combination with other materials, mix of materials, and is therefore lightweight, with smooth surfaces, minimumcontamination and possesses good insulation properties. FRP can also be used for non-cylindrical applications: read about one of these projects.
FRP products are ideal for on-site production and installation. Our international team of certified laminators handle installation jobs for customers all over the world.
