Technique may sustainably recover nutrients from urine
Membrane-based technique and closed-loop system may recover ammonia as valuable fertilizer product while removing it as pollutant from waste streams.
May 8, 2020
Ammonia is a key component of fertilizer and vital in supporting plant growth, ultimately providing food for populations around the world. It is also a major pollutant that, when released into the environment, could pollute aquatic settings and damage ecosystems, triggering destructive algal blooms, dead zones and fish kills, according to the Columbia University School of Engineering & Applied Science.
To date, most ammonia capture is done through an extremely energy-intensive technique known as the Haber-Bosch process, which is used by industry across the globe to produce fertilizer and accounts for 1-2% of the world’s annual energy consumption, the announcement said.
A Columbia Engineering team led by Ngai Yin Yip, assistant professor of earth and environmental engineering, reported the recovery of ammonia through a new method that uses a very low level of energy -- approximately a fifth of the energy used by the Haber-Bosch process. In addition, because the technique recycles ammonia in a closed loop, the ammonia can be recaptured for reuse in fertilizer and other industrial products. The findings were published by ACS Sustainable Chemistry & Engineering.
The management of nitrogen, an essential nutrient for life, has been recognized by the National Academy of Engineering as one of the Grand Challenges of the 21st century. Yip’s group, which focuses on advancing sustainable production of both energy and water, wanted to invent a better, more ecological way to produce nitrogen, of which ammonia is a bioavailable form.