CIWI's First Pilot is Up and Running at Brabant Water

Testing on a commercial Scale

We’re pleased to announce that our first pilot device is now operating at Brabant Water’s Zevenbergen process plant! Over the last two months, we’ve been testing CIWI’s technology on a commercial scale for the first time, putting our system and all key components from our suppliers through real-world trials.

The Zevenbergen plant produces process water for local industry, making it the ideal setting for our pilot. Our device can dissolve 40 metal plates (each 50x50 cm, 3 mm thick) in just 2.5 weeks, generating 0.5 kg of metal-based coagulant per hour.

So what are we trying to do here…

Metal salts are essential in water treatment and are often made from aluminum or iron compounds like iron chloride, which then form iron or aluminum hydroxide. These hydroxides help water particles clump together, or "coagulate." Traditionally, water treatment facilities have added metal salts to create these hydroxides, but producing metal salts requires harsh acids, leading to supply chain risks, high CO₂ emissions, and unwanted side effects in water treatment.

CIWI’s approach is to replace metal salts by directly producing metal hydroxide through electrolysis, using only clean water, salt, and iron. In our system, electrons are removed from iron plates, forming Fe²⁺ or Fe³⁺ ions. These ions combine with water to create iron hydroxide, which is then used in the water treatment process.

Here’s how it works:

  1. Preparing the Electrolyte: CIWI adds a small amount of salt to clean process water to prepare the solution that will carry the current needed for electrolysis.

  2. Electrolysis in the Reactor Pod: The prepared solution flows into the Reactor Pod, where 40 iron plates gradually dissolve over 2.5 weeks, producing iron ions that form iron hydroxide.

  3. Separation: The iron hydroxide can be collected out of the electrolyte. A seperation mechanism collects them so the electrolyte can be re-used.

  4. Oxidation: Some of it may not be fully formed, so air is added to complete the reaction before it goes into the water treatment process.

  5. Byproducts: The process also produces hydrogen gas, which is captured by a ventilation system and may be used in future setups to reduce energy use by up to 50%.

This method is 10 to 15 times more energy-efficient than conventional electrochemical methods like electrocoagulation and introduces 6 to 10 times less salt than metal salts. It also reduces or eliminates the need for caustic soda to neutralize acid, as is usually required with iron chloride.

At the pilot scale, this system can produce 0.5 kg of iron per hour, covering about a 10% of the Zevenbergen water treatment facility’s needs, which supplies 1,000 m³ of water per hour to local industry.

Next steps…

Over the coming months, we are actively conducting comprehensive water quality testing in collaboration with Brabant Water, with a particular emphasis on the process of “jar testing.” This lab-based methodology enables us to effectively simulate and analyze how our innovative product interacts with water under real-world treatment scenarios. Throughout the jar testing procedure, we carefully add our iron-based coagulant at various concentrations to a series of separate jars, each filled with water sourced from the Zevenbergen plant. Each jar is stirred at meticulously controlled speeds; we begin with rapid agitation to ensure an even distribution of the coagulant, and then switch to a slower stirring speed to facilitate the natural clumping together of small particles, a process known as flocculation. After allowing the samples to settle, we conduct detailed observations of each jar to ascertain the optimal concentration required to achieve clear, treated water.

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