AguaClara Research Lab
The AguaClara lab at Cornell, located in the basement of Hollister Hall, is part of an international collaboration that is creating improved systems for water purification plants. Monroe Weber-Shirk, Civil and Environmental Engineering, directs a team of more than 50 graduate and undergraduate students who research, invent, and design AguaClara plants, including fundamental mechanisms of flocculation, sedimentation, filtration, and gravity powered chemical dosing. Each year, Weber-Shirk and his students travel to Honduras to visit functioning plants as well as those under construction. “Besides inventing technologies that provide safe drinking water to communities in the Global South, AguaClara is providing students with engagement in real engineering work. The students are involved in every process—from inventing systems and technologies to fabrication and design. They travel and see how their research affects communities. It is a once-in-a-lifetime experience,” says Weber-Shirk.
Each AguaClara plant has a three-step process for cleaning dirty water. Water entering an AguaClara plant is mixed with a dosage of polyaluminum chloride, a coagulant that sticks to the particles and pathogens in the water. The water travels into the flocculator, where carefully engineered turbulence causes particle collisions. Particles collide as they travel through the flocculation system, creating large flocs visible to the human eye (0.1 mm to 1 mm). Water flows up through a sedimentation tank, causing heavy flocs to fall toward the bottom, creating a fluidized bed, or a floc blanket. The floc blanket aids in the capture of small particles. The mechanism of particle capture in the floc blanket is an active research topic. After passing through the floc blanket, water runs through slanted parallel plates, which catch more of the smaller flocs. Water then runs through another AguaClara invention, a stacked rapidsand filter. The water that exits is clean and meets government standards, often at a much higher quality than required.
AguaClara’s Honduran partner, Agua Para el Pueblo, built the first plant in Ojojana, Honduras in 2006, a year after the first plant design was completed at Cornell. Today, 12 plants serve communities in Honduras and two in India. Continuing research at Cornell improves the efficacy and effectiveness of new plants. They are gravity-powered, electricity-free, and scalable to the size of the community they serve. Plants are built using local labor and locally available materials. AguaClara improves public health and the sustainability of community water supply systems, because communities are willing to pay more for high quality, safe drinking water.