Unlocking the Potential of Wastewater: Resource Recovery for a Sustainable Future

Published in

Mark and Focus

4 min readSep 20, 2023

As our planet grapples with an expanding population and a rising demand for fresh water, treating wastewater efficiently is no longer just an environmental concern — it’s an urgent necessity. Properly managed wastewater not only safeguards our water supply but also provides opportunities to recover valuable resources. This approach lays the groundwork for a more sustainable and circular economy.

By Robert C. Brears

Energy recovery

One of the significant resources that can be extracted from wastewater is energy. The organic matter in wastewater — such as human waste, food scraps, and paper — serves as a potent feedstock for anaerobic digestion. This process produces biogas, a renewable source of energy. Biogas can be harnessed to generate electricity and heat, thereby minimizing our dependency on non-renewable energy sources and curbing greenhouse gas emissions.

Nutrient recovery

Another resource that can be reclaimed from wastewater is nutrients such as nitrogen and phosphorus. These elements can be repurposed as agricultural fertilizers, reducing the demand for synthetic alternatives and conserving natural resources. This is particularly crucial in regions where water scarcity is a pressing issue, as nutrient recovery lessens the need for water in irrigation.

Wastewater reuse for non-potable uses

Water itself is a precious resource that can be recovered from wastewater. Advanced treatment processes allow the purified water to be reused for non-potable functions like irrigation, industrial activities, and even toilet flushing. This practice not only conserves water but also alleviates the demand for fresh water, reducing the energy and costs associated with its transport and treatment.

Recovery of metals, cellulose, and bioplastics

Wastewater treatment can also be a source of metals, cellulose, and bioplastics, valuable resources that can be recovered and repurposed for other uses:

Metals: Elements like copper, zinc, and nickel are often present in wastewater and can be recovered for recycling. These metals are crucial for various industrial sectors, including electronics, construction, and transportation.
Cellulose: Cellulose, the main component of plant cell walls, is also present in wastewater, particularly in paper mill effluent. Cellulose can be extracted and used as a feedstock for the production of biofuels, textiles, and other value-added products
Bioplastics: Wastewater can be a rich source of biodegradable organic matter, which can be used as a feedstock for the production of bioplastics

Berlin Turning Waste into Resources

Berliner Wasserbetriebe’s Schönerlinde sewage treatment plant is turning sewage sludge into sewage gas to generate power and heat. Additionally, the utility has constructed three wind turbines, with a capacity of 2 MW each, as well as two micro gas turbines to complement the plant’s CHP unit. Overall, around 84% of the energy required by the plant is produced internally, saving up to 13,000 tons of carbon emissions per year. Berliner Wasserbetriebe has also developed a patented process for recovering phosphorus from its sewage treatment plants. The recovered phosphorus is sold under the brand name ‘Berliner Pflanze’ (Berlin Plant) to horticulture and agriculture producers in the surrounding areas of the city. Several years ago, Berliner Pflanze won the GreenTec Award for environmentally-friendly recycling products.

The Take-Out

By integrating these resource recovery techniques into existing wastewater treatment frameworks, we can create a sustainable loop that not only protects our environment but also contributes to our economy.