Demonstrations yield cleaner wastewater with energy benefits  

June 8, 2017

Two new clean water technologies under development by ISTC were demonstrated June 2 at the University of Illinois' Swine Research Center.

technology demo of  wastewater cleaning with algaeYoung Hwan Shin (left) and Chih-ting Kuo, graduate students in the department of agricultural, and biological engineering, explained the components of the multi-stage algae water treatment system.

The approaches address basic problems in water treatment in both the urban and rural wastewater realms and offer opportunities for renewable and sustainable energy sources.

The occurrences of natural and pharmaceutical hormones, from human and animal sources, in addition to nutrients in wastewater have caused concern among environmental scientists about their impacts in the aquatic environment. 

ISTC's Wei Zheng and Laurel Dodgen developed an easily deployable/scalable method for removing hormones from liquid manure in animal farm lagoons before it is discharged to streams or, in some cases, applied to crop land. Dodgen demonstrated that mixing wastewater with vegetable oil – particularly corn oil - removes at least 90 percent of certain hormones. The vegetable oil can subsequently be used as an energy source by making it into biodiesel.  The technology is also being studied for use in rural wastewater lagoons where treatment is accomplished by bacterial action.

The second demonstration dealt with technology under development by Lance Schideman at ISTC to benefit tertiary wastewater treatment plants (WWTP) employed in higher population centers. This approach reduces the nutrient load in wastewater by cultivating algae in-line at the WWTP. The plant growth removes both nutrients and carbon dioxide from the effluent. The algae is then transformed into biocrude by hydrothermal liquefaction, a process that uses high temperature and pressure.  This process also destroys any pharmaceuticals or hormones that were in the wastewater as the algae adsorb from them from the wastewater thus removing them before the wastewater is discharged to the environment.

Postdoctoral Research Associate Laurel Dodgen deploys a portable system designed to remove hormones from liquid manure.

This approach is already being tested at a Champaign-Urbana Wastewater Treatment Plant. The economic viability of the approach is improved by the energy production if the biocrude is distilled for drop-in fuels.

This topic of pharmaceuticals and hormones in the wastewater was also part of the Emerging Contaminants in the Aquatic Environment Conference, organized by ISTC, a division of the Prairie Research Institute, and the Illinois-Indiana Sea Grant Program, at the I Hotel on May 31-June 1. Three keynote addresses from the conference are now available on video:

"Microplastic and anthropogenic litter in rivers is abundant, mobile, and selects for unique bacterial assemblages"
Timothy Hoellein, department of biology, Loyola University Chicago

"PAHs and coal tar — old contaminants with emerging concerns"
Barbara J. Mahler, research hydrologist, U.S. Geological Survey

"Untangling the legal web surrounding emerging contaminants"
Stephanie Showalter Otts, director, National Sea Grant Law Center, University of Mississippi

A 2-minute video showing the devices demonstrated can be found at https://www.youtube.com/watch?v=YERkmYP5Pqk

 

Contacts: Nancy Holm or Beth Meschewski