Report on desalination, brine treatment and its potential impact on maritime life
Since October 2022, scientists, and consultants from the German institutions DECHEMA Gesellschaft für Chemische Technik und Biotechnologiee.V. and ISOE –Institute for Social-Ecological Research are analysing howthe hydrogen economy can be successfully developed in Namibia. These analyses are part of the project GreeN-H2-Namibia, which is funded by the German Federal Ministry of Education and Research.
One important aspect towards a hydrogen economy is the water demand arising from the production of hydrogen via electrolysis. In Namibia, the driest country in the sub-Saharan region,water must be obtained locally from seawater desalination plants or water re-use concepts, since groundwater alone will not be sustainable nor sufficient to meet the increasing demand in the future.To produce 1 kg of green hydrogen via electrolysis, about 10 kg of water is needed. This demand raises some questions such as: Where is this water obtained from? How will the water need to be treated before the hydrogen production? And, which impacts result from that? These questions were addressed in a report conducted by the project on behalf of the Namibia Investment Promotion and Development Board (NIPDB).
This report introduces seawater desalination as a well-known technology and a well-suited water source for the Green Hydrogen Industry in Namibia. It outlines the potential influence of brine on the maritime life and fishing areas along the coastline of Namibia under the assumption of different stages of Green Hydrogen production development. Most of this report will focus on brine discharge and its potential impact, mentioning also brine treatment and recovery strategies for salts and metals from the brine are also addressed.
"As the report deals with Namibia as a whole, follow-up reports are planned for the three hydrogen valleys mentioned by the Namibian Hydrogen Strategy: //Kharas, Erongo and Kunene. The follow-up reports will focus closeron the existing and required infrastructure. Furthermore, they will look in more detail at the regionally affected marine systems and water supply", says Robert Schmidt, part of the DECHEMA team in the GreeN-H2 project.
This report is intended to provide an outlook on potential issues related to desalination and the resulting brine discharge as well as possible alternatives in the context of the Green Hydrogen Industry in Namibia. The project team GreeN-H2 Namibia of DECHEMA and ISOE travels regularly to Namibia in order toaccompany the progress of the pilot projects, but above all to achieve a knowledge transfer together with all stakeholders along the value chain for green hydrogen, as well as to publish studies selectively.
About the project partners
DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. brings together experts from different disciplines, institutions and generations to promote scientific exchange in chemical engineering, process engineering and biotechnology. DECHEMA searches for new technological trends, evaluates them and accompanies the implementation of research results in technical applications. More than 5,800 engineers, scientists, students, companies and institutions belong to the non-profit association.
ISOE –Institute for Social-Ecological Research is one of the leading independent institutes for sustainability research. It develops scientific foundations and forward-looking concepts for socio-ecological transformations. To this end, ISOE conducts transdisciplinary research on global problems such as water scarcity, climate change, biodiversity loss and land degradation, and finds viable solutions that take into account ecological, social and economic conditions.