A team of engineers at the University of Colorado Boulder (CU-Boulder) recently developed a simplified treatment process that not only removes salt and organic contaminants from wastewater, but also generates energy. The microbial electrochemical approach takes advantage of energy-rich hydrocarbons that are found in wastewater contaminants, as well as in oil and natural gas. Known as microbial capacitive desalination, the new water treatment technology uses microbes to generate an electrical current similar to that of a basic battery. The microbes consume the contaminants’ hydrocarbons and release their energy, which serves as the source of a natural battery comprising both a positively and a negatively charged electrode. This electric current then facilitates desalination by attracting the positively and negatively charged ions of salt, causing them to adhere to the electrodes.
Featured as a cover story in Environmental Science Water Research & Technology, microbial capacitive desalination presents an alternative to current time-consuming, costly wastewater treatment methods that require oil and gas companies to expend large amounts of energy. Because CU-Boulder’s new treatment technology produces energy rather than consuming it, it creates the possibility for water treatment processes to power other on-site activities in oil and gas operations.