Recovery of Resources from Wastewater

Farmers grow food by cultivating plants and animals, with plants using sunlight for energy and water from the soil. Both plants and animals need nitrogen for protein production and phosphorus for genetic material and cell membranes. Since soil has little nitrogen or phosphorus in usable forms, farmers add fertilizers to boost crop yields.

When we eat, our gut microbes also feed on these nutrients. The unused nutrients, along with microbes, are excreted in wastewater. Domestic wastewater contains organic matter, nitrogen, and phosphorus, which can be converted by microbes in anaerobic digesters into methane, a form of natural gas. Microbes also convert organic nitrogen into ammonium, which can be captured and reused as fertilizer. Phosphorus can also be recovered, and the water can be purified and reused after nutrient removal.

Recycling wastewater, recovering resources, and obtaining clean water contribute to sustainable development.