Off to Colombia to purify water and develop eco-friendly showers

Marisa Boller et Jean-André Davy--Guidicelli at the Universidad del Valle. © EPFL

Marisa Boller et Jean-André Davy--Guidicelli at the Universidad del Valle. © EPFL

Two EPFL Master’s students in environmental sciences and engineering have headed to Colombia to carry out their internships. They’ll spend four months there working on two separate projects. You can follow their progress on the EPFL expedition blog, EPFL Out There.

In mid-October, Marisa Boller and Jean-André Davy-Guidicelli travelled to Universidad del Valle in Cali, near Colombia’s west coast, to carry out internships for their Master’s degrees in environmental sciences and engineering. They will stay there until next February and work on two projects under the guidance of researchers at the university and, at EPFL, of professor Christof Holliger. The students will post regular updates on the blog EPFL Out There.

#MasterInternshipCali (Colombia)

The first project will be conducted at the university’s Instituto Cinara, a research center for water treatment and purification. The project will help provide cleaner water to the residents of Mondomo, a village 70 km south of Cali. Although Mondomo already has an innovative, effective water purification system that Cinara developed in 1996 with the assistance of EU funding, after an earthquake destroyed the village’s existing purification system.

But the existing system can’t remove all the cyanide in the water. The cyanide results from the method used locally to process cassava. “Colombian farmers extract starch from cassava roots, but the problem is that the root-grinding and filtering process generates a lot of cyanide, which ends up in nearby rivers. Mondomo’s water purification system produces very clean water, but isn’t equipped to remove all the cyanide,” says Davy-Guidicelli. The students will first measure cyanide concentrations in cassava roots, the local plant’s wastewater and the local surface water. They will then study the different cyanide removal methods available and select the best one for Mondomo. They intend to publish their research in a journal article.

In parallel, Boller and Davy-Guidicelli will work on a project they started this year at the Student Kreativity and Innovation Laboratory (SKIL). SKIL is a fablab opened in 2018 by EPFL’s School of Architecture, Civil and Environmental Engineering (ENAC). It gives students an opportunity to work on projects they design themselves, with the assistance of ENAC professors.

At SKIL, Boller and Davy-Guidicelli developed their own version of the Showerloop, an eco-friendly shower originally invented by Finnish engineer Jason Selvarajan. The Showerloop consists of a closed-loop system where the same 10 liters of water are continuously used, purified and recycled – as opposed to conventional showers that consume an average of 100 liters of water.

The students created a “Swiss” version of the Showerloop at EPFL during the last year of their Bachelor’s programs, and now plan to adapt the concept to Universidad del Valle’s sports center. “By installing Showerloops at the university, we can help reduce water use in this region where water is scarce,” says Boller.

The students are already in contact with a fablab in Cali to produce three different types of Showerloops, which they will compare in terms of economic feasibility: an original Showerloop kit as designed by Selvarajan; a customized Showerloop that Boller and Davy-Guidicelli developed using materials that can be purchased entirely in Colombia (such as shower heads, active carbon filters and UV filters); and a self-sufficient version of this latter kit that can be operated by simply connecting it to an existing shower at the sports center. Here too, the students plan to publish their research in a scientific journal.