WLT Deutschland GmbH from Hamburg adopts a different approach to water generation. Based on platform technology developed by Fraunhofer IGB, WLT has developed a production-ready product for obtaining ultra-pure water in scalable quantities, even in arid areas far from any water bodies. In this interview, the founders, Michael and Helen Saur, explain the concept.
How does your product work and what does it do?
The basic principle of WLT technology is liquid absorption. Water molecules from the ambient air are bound with the help of a hygroscopic saline solution. As this is not easy to do, WLT uses a seven-metre high cylinder with a diameter of two and a half metres. This contains a filling that makes it easier for the hygroscopic saline solution to come into contact with the water molecules from the air compared to other technologies. Ambient air is drawn into the cylinder from below via a fan mounted on top of the cylinder. At the same time, the saline solution is sprayed from above using a sprinkler. A significantly diluted saline solution finally drains from the cylinder and is fed into the desorption module, where it is heated so that the saline solution can be separated from the pure water and returned to the cycle. Ultimately all that remains is extremely pure water with conductivity of below 15 µS/cm (microsiemens per centimetre). Depending on the product location, the amount of water that can be produced will vary, due to the prevailing meteorological conditions.
What makes the WLT product so special is that it is almost infinitely scalable. In principle, any amount of water can be produced, whether 0.5 litres or 2,000 litres are required. In addition, WLT is predominantly mobile. Extremely pure water can therefore be produced with just 10 percent humidity. This makes the product ideally suited for use in arid regions, i.e. areas that are currently the focus of global hydrogen production.
What is the technical status of your product?
The product is ready for series production. WLT is currently in the process of certifying the product to allow its worldwide launch. We expect to implement this in spring 2023 via an internationally recognised certification company. WLT performed proof-of-concept back in 2017 in the Atacama Desert in Chile, where a pilot facility produced water for eight months.
Which market does your product target and who might the customers be?
It is important that WLT is not regarded as a competitor to conventional desalination plants, but as an additional, complementary provider. This will also give regions with water shortages the opportunity to attract new technologies and industries, providing a green solution for existing companies with high water consumption. As water from WLT is extremely pure and produced in large quantities, WLT primarily focuses on industrial customers.
Its target customers are therefore those who use extremely pure water for electrolysis, e-fuel manufacturers and the semi-conductor industry. WLT is also able to produce water for winegrowers, mines and mining camps, as well as the food and beverage industry, by mineralising the generated water to meet individual customer requirements.
How can your product help reduce socio-political tensions surrounding global water scarcity?
For the first time, WLT makes it possible to produce water where it was previously impossible to do so. Far from seas, rivers and lakes, for example. Larger companies, including in the mining industry, that are currently in conflict with consumers of natural water resources can benefit from the improved water supply. This can also prevent the local population from losing their ground and drinking water. WLT aligns all its products with the UN’s Sustainable Development Goals, especially with Numbers Six (Clean Water and Sanitation), Nine (Industry, Innovation and Infrastructure) and Fourteen (Life Below Water).