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Optimised water solutions for sustainable green hydrogen production.
Ultrapure water is essential for producing high-quality hydrogen and maintain optimal electrolyser performance. Insufficient water treatment can compromise operations and even damage the electrolyser.
The type of electrolysertechnology and feedwater determines the required water treatment process. We ensure that you get the right solution through our industry leading expertise, wide range of standard products and international support – and help your business from water source to the heart of the electrolyser.
Did you know? Key water facts in hydrogen production
The amount of ultrapure water is 9 m3 for 1 ton of green hydrogen
But why ultrapure water? Several factors determine the required water quality, and each ion and molecule present in the water impacts the electrolyser differently. To avoid this ultrapure water is essential.
Electorlysers need 50 to 100 m3 of DI water per hour for every MW
To prevent temperature increase in the electrolyser, a high flow rate of 50-100 m³/h per MW is essential for the recirculation of ultrapure water and KOH solutions. This is 250-500 times larger than the pump capacity needed for the ultrapure water going into the electrolyser.
25% of energy going into electrolysis needs to be cooled away
Electrolysis not only produces green hydrogen but also generates a lot of heat. Cooling towers play a crucial role in dissipating this excess heat, and pumps are at the heart of the cooling process. They ensure a continuous flow of water to maximise heat exchange, helping to keep the process stable and energy efficient.
Tailored water treatment across all electrolyser technologies
Our water treatment solutions for hydrogen production start with a tailored pretreatment step, based on the specific characteristics of the sourced water. This is followed by a series of polishing steps, which vary depending on the electrolyser technology used. Whether it's softening, deionization, or other advanced treatments, we ensure the production of ultrapure water essential for maintaining the function of the electrolyser and ensuring efficient hydrogen production.
We specialise in water treatment for:
- Alkaline water electrolysis (AWE)
- Polymer electrolyte membrane electrolysis (PEM)
- Internal polishing in connection to PEM
- Solid Oxide Electrolysers (SOEC)
- Anion exchange membrane electrolysis (AEM)
Grundfos Water Treatment Europe (former EUROWATER) has designed and manufactured the water treatment solution for the world's first commercial plant that increases biogas production through electrolysis and biological methanisation.
Learn about efficient water treatment to enchance electrolyser systems
Whether you're looking for an in-depth exploration of refinement loops and seawater usage in hydrogen production, or just a brief overview of the importance of water treatment, our whitepapers have you covered. Dive into our comprehensive resources to uncover the benefits of proper water treatment in the hydrogen production process.
Reliable and safe hydrogen production calls for energy-efficient pumps. The pumps are responsible for transporting water through various stages of the hydrogen process, playing a central role by moving a large amount of heat during the electrolysis process to maintain an acceptable temperature differential across the electrolyser stack.
Learn everything you need to know about pump solutions for green hydrogen
Pumps in green hydrogen systems ensure a consistent supply of fresh water for electrolysis, circulate water to remove impurities, maintain the flow of deionised water, and dissipate heat generated during electrolysis and other plant operations. Download our whitepaper to discover all the jobs to be done.
Frequently Asked Questions
How much water do I need for my electrolysis process?
How much hydrogen can I produce from my water?
Water contains two atoms of hydrogen and one oxygen atom. Because oxygen is 16 times heavier than hydrogen, it takes up most of the mass in a water molecule. 89% of the mass is oxygen and 11% is hydrogen. This means that to produce 1 kg of hydrogen, 9 kg of water are required. In reality, 10-13 kg of water are required due to losses and inefficiencies.
What is ASTM water quality?
ASTM Type I, II, II and IV are a set of international standards for water quality often used to describe water quality requirements for electrolysers. They cover conductivity/resistivity, sodium, chloride, TOC and silica, but in reality, they are often insufficient to properly describe the water quality needs for electrolysers.
Where do I need water treatment?
Can I use seawater or treated wastewater as feed water for electrolysis?
Yes. Each source of water requires special attention to specific constituents in the water and you need to take variations in the inlet water quality into account. In general, we can say that wastewater requires special attention to nutrients and microorganisms that can cause biofouling, as well as the load of organics, while seawater requires focus on high retention of ions.
How does water quality affect lifetime of electrolysers?
How do I achieve the required water quality for electrolysis?
Typically, we need first to bring the raw water to a state similar to drinking water quality. From here the water most be conditioned to avoid scaling, after which a RO process is used to remove the bulk of the ions, organics, and colloids. A targeted process is also required to remove dissolved gasses. Finally, a polishing step can be implemented depending on the specific needs of the electrolyser.
What material should the pump be made of for my hydrogen system?
Do I need to worry about electro corrosion in the pump shaft-seal when producing hydrogen?
What size of projects does Grundfos Water Treatment cover?
What sizes of pumps does Grundfos offer for hydrogen production?
If you are interested in knowing more, please reach out to us.
Ensuring seamless electrolyser operation through advanced water treatment
Maintaining the right water quality is essential for the efficient and reliable operation of Polymer Electrolyte Membrane (PEM) electrolysers. Impurities in the water can accelerate corrosion, reduce efficiency, and damage critical components, leading to increased maintenance costs and operational downtime.
We have you covered with advanced water treatment solutions for PEM electrolyser throughout the green hydrogen production.
Treating and handling water to PEM quality
- Removes calcium and magnesium from water, avoiding clogging of RO membranes.
- Prevents calcium deposits in piping, steam boilers, hot water units, heat exchangers, and cooling towers.
- Enhance a reliable operation and extend the lifespan of other units.
- Demineralised water by membrane filtration for ultrapure feedwater
- Removes more than 98% of dissolved salts, microorganisms, bacteria and most organic substances, thereby reducing microbial corrosion.
- RO-PLUS water saving technology available for a recovery rate up to 90%.
- Equipped with e-pump for high energy efficiency
- Removes dissolved gases from the water without using chemicals.
- Compressed air is used as a strip gas.
- Reduces CO2 levels significantly, resulting in lower conductivity of the water.
- Used after reverse osmosis for polishing of RO permeate
- Maintain low levels of conductivity, TOC and silica
- Electrochemical regeneration for a continuous process without need for chemicals or resin exchange
- Alternative to a conventional mixed-bed polisher in the make-up treatment train
- Used for polishing of ultrapure make-up water and continuous polishing in PEM refinement loop
- Ensures conductivity below 0.1 μS/cm
- No chemical storage needed due to off-site regeneration
- Available in standard PPA coating for make-up water and stainless-steel w/o coating for refinement loop
- Selected resins for make-up water and refinement loop
European Energy has opened the world’s first large-scale commercial e-Methanol production facility in Kassø, Aabenraa, Denmark. Grundfos Water Treatment provided the water treatment solution for the 50 MW PEM electrolyser, which requires a steady supply of 10,000 liters of ultrapure water per hour with a conductivity below 0.1 μS/cm. Download the case story to read more about the water treatment solution.
Water treatment only makes up about 1% of the total capital cost of an electrolyser system. However, neglecting proper water treatment can jeopardise the entire operation. In other words, while investing in good water treatment might not significantly impact the business case, doing it poorly can lead to failure and substantial losses.
Maintaining ultrapure water to power peak performance in PEM electrolysers
During electrolysis, the composition of the water changes, releasing harmful ions into the DI-water loop. To prevent contamination, it is essential to continuously treat the ultrapure water. This is achieved by processing a side stream of the DI-water loop in a refinement loop, which typically involves deionization and particle filtration.
As a general guideline, the refinement loop in PEM systems should handle a flow equal to 1–5% of the DI-water loop to ensure optimal performance and efficiency.
Explore critical water treatment challenges unique to PEM electrolysers
It’s a fact that the water used for electrolysis must be of very high quality. However, treating the feedwater to the required quality is only half the story. Maintaining this high water quality while it circulates inside the electrolyser is equally crucial. This white paper explores the dynamics of water within the electrolyser and the implications for water treatment in a refinement loop.
Frequently Asked Questions
What quality of water do I need for my electrolysis process?
The quality depends on the type of electrolysis equipment you use, alkaline or PEM, and from which manufacturer the equipment is supplied. From a conductivity perspective, values can vary from 0.056-5 µS/cm, but many constituents affect the electrolysis process depending on the specific technology used.
Where do I need water treatment?
Should I use EDI or mixed bed in my polishers?
Which resin should I use for polishing water for electrolysis?
What size of projects does Grundfos Water Treatment cover?
If you are interested in knowing more, please reach out to us.
Achieve peak performance in alkaline electrolysis with ultrapure water
Ensuring ultrapure water is essential for the optimal performance and longevity of alkaline water electrolysers. Proper water treatment removes unwanted impurities and compounds that could interfere with the electrolysis process, minimizing the total cost of water treatment by preventing the buildup of pollutants within the system.
Explore our advanced water treatment technologies designed to achieve sustainable and efficient hydrogen production by maintaining the required water quality for the alkaline electrolysis process.
Treating and handling water to alkaline quality
- Removes calcium and magnesium from water, avoiding clogging of RO membranes.
- Prevents calcium deposits in piping, steam boilers, hot water units, heat exchangers, and cooling towers.
- Enhance a reliable operation and extend the lifespan of other units.
- Demineralised water by membrane filtration for ultrapure feedwater
- Removes more than 98% of dissolved salts, microorganisms, bacteria and most organic substances, thereby reducing microbial corrosion.
- RO-PLUS water saving technology available for a recovery rate up to 90%.
- Equipped with e-pump for high energy efficiency
HySynergy I 20MW is one of the largest green hydrogen production projects in Europe, led by Everfuel. The Grundfos Water Treatment solution at the HySynergy facility consists of softening by ion exchange and double-pass RO to meet the quality level of the make-up water.
Many will say that 5 µS/cm should be the lower conductivity limit for standard alkaline electrolysis, but what we see from the market today is a trend towards higher requirements for water quality – also for alkaline electrolysis.
Maintaining ultrapure water to improve alkaline electrolysis efficiency
The formation of particles in the feedwater can clog the electrolyser and lead to operation downtime. To prevent this, the entire flow must be treated in a refinement loop to maintain the water quality inside the electrolyser.
This white paper unfolds the dynamics of water within the electrolyser and provides you with valuable insights into the refinement of water for alkaline electrolysis.
Frequently Asked Questions
What quality of water do I need for my electrolysis process?
The quality depends on the type of electrolysis equipment you use, alkaline or PEM, and from which manufacturer the equipment is supplied. From a conductivity perspective, values can vary from 0.056-5 µS/cm, but many constituents affect the electrolysis process depending on the specific technology used.
Where do I need water treatment?
What size of projects does Grundfos Water Treatment cover?
If you are interested in knowing more, please reach out to us.