GWR Project at Expoagua 2024:

The Greywater Reuse Project (GWR) will showcase scientifically proven and economical solutions at Expo Agua 2024 on October 10 at the Metropolitan Santiago (formerly CasaPiedra). The GWR project opens up water-saving and thermal insulation options to anyone who wants to implement them in their home without the need for specialized labor.

The inter-university scientific team, comprised of researchers from Usach, UNAB, and the University of Bío-Bío, will present its work at Expo Agua. The team's research focuses on generating strategies to reduce residential drinking water consumption through the reuse of treated gray water by integrating electrochemical processes and membrane technologies.

"At Expo Agua, the GWR project aims to reach a wide audience and showcase the initiative's progress. This includes demonstrating how electrochemistry is used to treat gray water and how the treated water is used to irrigate ornamental plants without causing negative effects. Additionally, the project will present a build-it-yourself prototype that treats and reuses gray water from washing machines for domestic activities such as irrigation and vehicle washing, which do not require drinking water," says Dr. Esteban Quijada, director of the GWR Project.

He points out that gray water accounts for up to 70% of the water used in the home. "Therefore, its reuse significantly impacts reducing household consumption, which is highly relevant in the context of a water crisis. Although the central region received some relief with the accumulated rainfall last fall and winter, according to the Ministry of Public Works, we are still below historical levels and in a drought that has now lasted fifteen years."

Low-Cost System

Chemical engineer Arael Alfonso, who is pursuing his Ph.D. in Process Engineering at the GWR Project, details the characteristics of the filtration system that will be presented at Expo Agua:
"This is an alternative technology to those evaluated in the project. It is characterized by being effective, economical, and easy to operate and maintain. It is commonly used as a sand filter, though it also includes materials such as stones, gravel, and sponges. Adding activated carbon to these filters makes the technology more robust and increases the efficiency of gray water treatment."

According to Alfonso, "In addition to not requiring specialized labor and being installable in any house or apartment, the materials used in this filtration system are inexpensive."

In line with showcasing sustainable and affordable solutions, Expo Agua will present a green wall option that can be installed with a limited investment, using planters and commonly sold plant species, without sacrificing thermal insulation, unlike those offered by suppliers of such structures.
Results of plant species irrigated with three types of water will also be exhibited: untreated gray water, gray water purified by electrochemical processes, and drinking water. Preliminary analyses show that spider plants (Chlorophytum comosum), white ivy (Hedera helix variegata), and Dymondia (Dymondia margaretae) are well-suited for this type of green infrastructure and thrive in the Metropolitan Region's climate.