Dhaval Mehta, Hui Zhi, Surya Kumar
Abstract
AguaClara is an engineering program based at Cornell University that develops sustainable water treatment technology with current applications in developing countries. In Honduras, one of the countries with AguaClara technologies, the treatment plant at San Nicolas experiences raw water with a temperature gradient of around 1°C/hr during warming and cooling portions of a day. These gradients are primarily caused due to the approximately 15km of piping that brings raw water to the plant, much of which is exposed to the sun. Agua Clara plants use sedimentation tanks with floc blankets and plate settlers. The temperature gradient during warming periods causes a circulation current to form in the vertical Gflow sedimentation tank, due to the effect of continually warmer water displacing colder water. This current in the tank at San Nicolas causes flocs to aggregate on one side of the tank and rise up to the top with the hotter, less dense water; hence the effluent water leaving the tank is not sufficiently clean. Our experiment is motivated by this problem, with the goal of studying the problem’s origins and providing initial research towards its solution