Researchers in California used radiofrequency power to significantly clean up wastewater from dairy, calf and swine facilities. This diagram shows how the material flowed through their prototype.

Researchers at Crocker Nuclear Laboratory and the University of California-Davis School of Veterinary Medicine have spent the last three years looking into new ways to disinfect farm wastewater before it’s recycled for use. And it’s been time well spent.

The experiment featured radiofrequency power, which is a physical method of electromagnetic energy input that heats a product uniformly throughout, leaving no chemical residues. The process operates with electrical power that generates a rapidly oscillating electric field between two parallel electrodes. The material to be processed is placed between these electrodes.

Using this method, the researchers were able to completely inactivate bacteria in wastewater from dairy, calf and swine facilities in under a minute when temperatures of 140 to 149 degrees F. were achieved. Before treatment, the samples contained high levels of Salmonella sp., Escherichia coli 0157:H7 and Mycobacterium avium ssp. paratuberculosis. Therefore, the scientists theorize this method offers a real alternative to livestock producers who recycle wastewater. The next step is to test it on-farm.