A Novel Approach to Purifying Greywater for Agricultural and Third World Applications

Friday, February 17, 2017
Exhibit Hall (Hynes Convention Center)
Khushi Thakkar, Texas Academy of Science, Plano, TX
Droughts in the U.S alone have cost the economy billions of dollars and thousands of jobs. To conserve water, stringent water restrictions are put in place, but these restrictions prevent plants from carrying out crucial biological processes and still do not balance the amount of water that households waste each day. To solve these issues, a water filter was engineered to remove household contaminants such as soap, oil, and food particles from greywater to be used for agricultural purposes. The effectiveness of Commercial Grade, Banana-Peel , Orange Peel, Tea-Waste, and Coffee-Waste Derived Activated Carbon was tested against 4 forms of greywater. Results concluded that the Banana-Peel Derived Activated Carbon removed 87% of contaminants on average, making it the most effective form of activated carbon. The filter was composed of a 2 step design consisting of both a Primary and Secondary filter. The Secondary Filter allowed dense contaminants to sink, then pushed water into the Primary filter, which was composed of Banana-Peel Derived Activated Carbon, Sand, and Gravel. In order to test if the water filter was safe for both plants and invertebrates, growth and biological processes of grass and Daphnia magna were analyzed respectively. A comparison of grass growth and the analysis of heartbeat patterns of Daphnia magna in tap water, filtered, and contaminated water concluded that the filtered water supported healthy plant growth and was safe for aquatic organisms. Overall, this water filter proved to be a cost efficient, effective, and an environmentally friendly approach for filtering out household contaminants from water.