Discipline: Technology and Engineering
Subcategory: Environmental Engineering
Ebone-Alexandria Ross - University of Miami
Co-Author(s): Lucien W. Gassie,University of Miami; James D. Englehardt, University of Miami; Kusumitha M. Perera, University of Miami
The likelihood of a global killer pandemic is now greater than ever due to increased population densities and global trade, transportation, migration, and climate change factors. In remote areas with limited access to clean water, disease outbreaks can have a much larger impact than in areas where clean water is available. For instance, the recent Ebola crisis in Africa brought to light delays in health care response due to a lack of running water at remote sites. In this case, net-zero greywater (NZGW) systems may be an appropriate solution, allowing users to wash hands or shower in between patients while avoiding risk of cross contamination. This solution differs from some existing options, such as the U.S. Army’s Shower Water Reuse System (SWRS). With the NZGW system, an 85% recovery rate is achieved, with the remaining 15% meeting drinking water standards and being discharged for irrigation, compared to the SWRS’s 75% recovery rate with the 25% discharge potentially containing concentrated pathogens that would require additional offsite treatment following discharge. An ozone-UV advanced oxidation NZGW system with shower and sink was designed, constructed, and operated at the University of Miami, and tested for shower loading capacity. Experiments were conducted consisting shower use at set time intervals, and sampling and analysis of waterborne chemical and microbiological constituents, in respect to compliance with US federal drinking water standards and performance with respect to design goals. The system’s capacity to handle shock events, such as urination was also evaluated. The water quality was examined in terms of meeting total organic carbon<0.5 mg/L and pathogen inactivation including 12 log virus, 10 log protozoa, and 9 log bacteria, Water Reuse Research Foundation recommendations for direct potable reuse. As controls, Campsuds diluted 25% was selected for use as shampoo and soap based on its low organic loading, while Garnier Fructis biodegradable conditioner was selected due to its neutral pH and claimed biodegradability when compared with other conditioners. In terms of organics and pathogens, the system met design goals. Drinking water standards were also met, except bromate and nitrate which were assessed for short-term use. Urine is proposed to be addressed by conductivity detection followed by tank drain and refill, treatment completion is signaled by UV254. Further research should focus on bromate mitigation, and long term microbiological studies should be conducted. References: Gassie, L., Englehardt, J., 2017 (under internal review). Mineralization of greywater organics by the ozone-UV advanced oxidation process: Kinetic modeling and efficiency. To be submitted to Water Research. Gassie, L., Englehardt, J., Brinkman, N., Garland, J., Perera, K., 2017 (under internal review). Net-zero water wash station for remote emergency response healthcare units: Design, operation, and results. To be submitted to Water Research.
Not SubmittedFunder Acknowledgement(s): This material is based upon work supported by the National Science Foundation under Grant Nos. 1519058 (REU) and 1038257(REU). In addition,contributions by the University of Miami, the US Environmental Protection Agency, and Engineered Control Systems, Inc. are gratefully acknowledged. The authors would also like to thank Spartan Environmental Technologies for technical collaboration.
Faculty Advisor: James D. Englehardt, jenglehardt@miami.edu
Role: I participated in the sampling and analysis as well as discussed results at weekly research meetings in order to come up with the conclusions of this project. I am interested in net-zero water research because through my involvement in research and in my studies I have noticed the importance of a sustainable economy and environment. I enjoyed working on a project that is the starting ripple to conserving and reusing resources and developing ways of waste transformation while building a water footprint. The three pillars of sustainability are people, planet, and profits and net-zero water systems pave the way for cost reduction, environmental preservation, and value for future communities and countries in need.