Wastewater is, in essence, contaminated water. Historically, wastewater has been seen as something we no longer use, to be disposed of as we replace it with clean water. But is wastewater actually waste? Engineers and scientists have begun re-evaluating wastewater and realising that the waste minerals and chemicals in it can be mined and recycled, saving valuable resources at the same time as reducing pollution.

Hydrogen from battery recycling plants

Researchers at the University of Technology Sydney, Australia, have developed a way of recovering metals from wastewater from a lithium-ion battery recycling company. The team recovers materials such as copper, nickel, cobalt, manganese and iron that they can then use for the production of hydrogen. The same team is now researching the possibility of recovering resources from other industrial wastewater.

Recovering precious metals

A surprising amount of gold and other precious metals get flushed into the world’s drainage systems, all of which have to be removed as part of the sewage treatment process. Until recently, these have simply been discarded, but engineers are now beginning to realise how much wastewater contaminants could be worth. Research in the US shows that metals worth up to $13 million could be recovered annually from wastewater created by a community of a million people.

The financial rewards that can be gained from ‘harvesting’ metals from wastewater sludge are obvious, but there is an additional bonus for the environment in that the sludge, with those metals removed, can then be used as agricultural fertiliser.

Cooking with wastewater gas

Renewable biofuel/biogas from wastewater has the potential to meet energy demands without the need for fossil-based fuels. It will have the additional benefit of minimising greenhouse gas emissions. The discharge of wastewater with high organic strength has increased enormously in recent decades. The authors of Clean Energy and Resource Recovery believe that “the organics present in the wastewater could be transformed into biogas through biological or biochemical processes and also, the contaminants could be alleviated. The knowledge of wastewater to biogas conversion is crucial to improve bioenergy production with a reduced operating economy.”

The authors conclude: “All these wastewaters have a rich source of nutrient that can be used for numerous uses such as energy generation, biofuel production, and organic fertilisers.” They also believe that, in addition to creating sustainable fuel, this method of recovering biogas will also help to manage the water crisis.

At a time when Russia is reducing gas supplies to Germany and the rest of Europe, we need to find alternative solutions to fossil fuels that will enable countries to be less dependent on others. Sustainable solutions such as biofuel/biogas could take us a long way towards this.

Wastewater treatment services

Working alongside our specialist partners, we can advise and assist you in finding the right solution for treating wastewater that cannot be discharged into the sewer. Whether you are a small business, or a multi-site company which produces a high volume of wastewater, we can provide you with the right knowledge and expertise you need to find the best solution for your business.

More and more people are choosing Castle Water because of our market leading expertise in waste and trade effluent. Speak to our helpful team on webchat or discover our services like wastewater management or business water services.


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