In a future where fossil fuels are increasingly relegated while relying on renewables, hydrogen is destined to play an important role. Energy storage is a function that hydrogen stored under pressure could perform with solvency, with the permission of lithium-ion batteries. The technology for storing and transporting hydrogen is still expensive, but its benefits as an energy vector are many. Hence, different research teams work around the world exploring the possibilities of this gas in the energy industry.
In Australia, ARENA (Australian Renewable Energy Agency) has made considerable efforts in this area. These include the recent approval of funds worth $ 9.41 million to the company Hazer Group. The objective? The creation of a plant to convert wastewater into biogas and, from there, move on to hydrogen.
This company has worked on a method to generate hydrogen gas alternatively. The two main techniques, which are commonly used, are electrolysis and steam reforming. The latter involves the transformation of hydrocarbons, generally methane (CH4) through its interaction with water vapour. The result is hydrogen gas and carbon monoxide. It is a polluting process, therefore.
The same does not happen with electrolysis. This consists of breaking the water molecule to obtain H2 on one side and O2 on the other. There is no contamination here. If the energy needed to divide the water molecule comes from renewable sources, the whole process is clean. The problem is usually that the energy contribution is very important.
The Australian company Hazer Group tries to do it differently. His idea is to convert wastewater, a material from which it is already possible to obtain biogas. This biomethane, which is generated from the components present in these waters, is separated by an iron catalyst.
From this step hydrogen and graphite are obtained. Both materials are used for industrial purposes, according to the company. The first as an energy vector. The second, as a source to obtain carbon black (for pigmentation or reinforce tires) and for the anode of the batteries.
Wastewater, a Source Of Wealth
Hazer Group will build a plant with the capacity to process 100 tons per year. It will rise in Western Australia, in Munster, and cost $ 15.8 million. Although they are not the only ones that have been fixed in wastewater to obtain hydrogen. A team of Spanish researchers tried some years ago to generate this gas through the use of exoelectrogenic bacteria applied to this type of waste.
The Australian company will sell hydrogen for industrial applications, in order to make its operations profitable. He hopes that, if all goes well, the process can be exported to other water treatment plants in Australia. It would, of course, be good news.