<p style="text-align: justify;">In 2002, WHO reported that nearly 1.7 million deaths worldwide were caused by unclean <br />water. The risk of death by unclean water is elevated for young children, for which the second <br />cause of death worldwide is diarrheal disease, which is largely caused by microbes; these <br />microbes, when unaddressed, can proliferate in drinking water. Health risks are further elevated <br />in rural communities, which often lack access to the technology necessary to treat water for <br />microbial contamination. This can be seen in Ecuador, in which only 52.8% of rural households <br />have access to safe drinking water.</p>
<p style="text-align: justify;"><br />The problem of infected drinking water in rural communities begs the question: how does <br />one effectively eliminate the risk of microbial contamination without the use of electricity and <br />complex, expensive components? A solution: passive chlorination. Passive chlorination systems <br />use the flow of the water itself to release chlorine into the water. The chlorine then disinfects <br />the water, leaving it safe to drink.</p>
<p style="text-align: justify;"><br />The research that I conducted this summer, in conjunction with related research <br />conducted by a team of professors and engineering students, primarily involved assembling and <br />testing a chlorinator that was determined by literature review to be the most promising option <br />of several different passive chlorinators. The CTI-8, designed by Compatible Technology <br />International, is a low-cost chlorinator that can be made using hand tools and commercially <br />available PVC components. Using the provided instructions for building a CTI-8, I constructed and <br />tested one in a model system that was meant to mimic the flow conditions in Ecuadorian <br />communities. The model system was comprised of a hose-fed 50 gallon upper tank, a main pipe <br />line that split into two lines (one with the CTI-8 and one without it), a bypass valve, and a 50 <br />gallon lower tank into which both lines drained. This model system provided a way to run a series <br />of experiments to determine the dosing capabilities of the CTI-8, and to determine how to adjust <br />the bypass valve that controlled the ratio of water that went through the chlorinator versus the <br />ratio that bypassed the chlorinator.</p>
<p style="text-align: justify;"><br />The ability to control this ratio proved to be a very reliable means of controlling the final <br />combined concentration of the two lines. If more chlorine was needed in the lower tank, the <br />amount of water bypassing the chlorinator was reduced, and vice versa. Additionally, the CTI-8 <br />proved to be very effective at consistently dosing water for a wide range of flow rates. For this <br />reason, the CTI-8 will be implemented for an Ecuadorian community by July 2023. <br />Working with a team to develop and test a real-world solution has been eye-opening to <br />the multi-faceted nature of real-world engineering problems. In the case of Ecuador, access to <br />clean water is a societal, economic, and technological issue, making it a challenge to create an <br />appropriate solution that meets the needs of Ecuadorian communities.</p>