Thirsty hydrogen

The challenge

Production of green hydrogen by electrolysis requires water of ultrapure (UP) quality. Essentially any raw water type can be used, provided that the water treatment line is adjusted accordingly. For hydrogen production nearby or at sea the obvious choice is seawater. For inland production other sources shall be identified, including surface water, groundwater or effluent from sewage treatment plants. Here the question arises: is a zero-waste concept achievable?

Solution and impact

In a specific case brackish surface water appeared to be the best available source locally. Allied Waters designed a dedicated treatment line based on the philosophy (1) minimizing the use of treatment chemicals and (2) developing a beneficial use of all side streams, the UPzero® concept. The concentrated brine is further thickened by using a part of the surplus heat generated during the electrolysis. The remaining product is suitable for use as road salt.

Status

A more detailed engineering study based on the UPzero® concept is ongoing, due for realization during 2027.

Learn more here.