A Performance Evaluation of a UASB Reactor and a Facultative Pond to Determine the Feasibility of Reusing Wastewater for Irrigation AND Laboratory Assessment of Four Point-of-Use Water Treatment Filters Designed for Households in Developing Countries

Matthew E. Verbyla, M.Sc. Candidate

Department of Civil and Environmental Engineering

University of South Florida

According to the United Nations 2011 Millennium Development Goals Report the percentage of undernourished people in the developing world has remained relatively stagnant during the past decade, despite significant reductions in poverty. The world is also far from meeting the sanitation target, with almost half of the population in developing regions without access to improved sanitation. In order to increase food production to meet rising demands in the developing world, many farmers use wastewater (treated and untreated) for irrigation. The use of inadequately-treated wastewater for irrigation greatly increases the risk of transmission of excreta-related diseases, especially for vulnerable groups such as those living in extreme poverty. Instead of focusing on the removal of traditional physical-chemical parameters from wastewater with the ultimate goal of discharging to surface waters, wastewater treatment in developing countries should be centered on the removal of human pathogens, with the ultimate goal of safe reuse. The reuse of wastewater for irrigation is very important, especially in certain regions of of the world experiencing water stress. This presentation will focus on a recent study comparing the pathogen removal and the performance of two waste stabilization pond systems in Bolivia which utilize different methods of primary treatment: an upflow anaerobic sludge blanket (UASB) reactor and a facultative pond. The goal of this research is to evaluate the feasibility of reuse for irrigation in accordance with the 2006 World Health Organization (WHO) Guidelines.

Biography

Mr. Verbyla graduated from Lafayette College in 2006 with a B.S. in Civil and Environmental Engineering, and is now pursuing an M.S. in Environmental Engineering at the University of South Florida. Mr. Verbyla is a LEED Green Associate and a Project Engineer at HRP Associates, Inc. and has several years of consulting experience on a wide range of wastewater, solid waste, potable water, and stormwater projects. Mr. Verbyla spent two and a half years studying, working, and volunteering in rural developing and urban slum communities of Central and South America, and is fluent in Spanish and conversational in Portuguese. He was also the recipient of a Fulbright Fellowship in 2007, where he studied the effects of decentralization policies on the sustainability of rural water systems in Honduras. His current research focuses on wastewater reuse and the removal of pathogens in wastewater treatment systems in developing communities of the world. Mr. Verbyla can be contacted at verbylam@mail.usf.com. 

Laboratory Assessment of Four Point-of-Use Water Treatment Filters Designed for Households in Developing Countries

Sarah Ness

Civil & Environmental Engineering

University of South Florida

According to the World Health Organization (WHO) and UNICEF’s Joint Monitoring Programme, 884 billion people do not have access to improved sources of drinking water.  Household water treatment technologies, termed point-of-use (POU) technologies, have been developed in an effort to solve this problem and improve peoples’ access to clean and safe drinking water.  

A laboratory assessment is evaluating the effectiveness of four POU treatment technologies that utilize physical filtration methods.  The two clay ceramic filters are further being evaluated in longer term field studies. Three of the systems, Potters for Peace, Filter Pure, and Tulip filters, are ceramic filters that treat water through filtration and also disinfect the water through the use of impregnated or coated silver.  The Potters for Peace (PFP) filter is a flower pot-shaped, 8 liter (L) ceramic filter with a silver coating.  The Filter Pure (FP) filter is a rounded-bottom lemon-juicer shaped, 7 L ceramic filter with silver fired into the ceramic.  The Tulip filter is a submersible candle-type ceramic filter that uses siphon pressure to push water through the filter element, which includes silver impregnated into the ceramic.  The fourth filter included in this evaluation is the LifeStraw Family (LS) filter, which utilizes ultrafiltration and water disinfection through chlorination.  

In the laboratory, flow rates, turbidity removal, total suspended solids (TSS) removal, coliform removal, and E. coli removal have been measured.  All four filter types have been tested using natural pond water.  Additionally, the PFP and FP ceramic filters have filtered tap water to simulate rain water, while the Tulip filters and LS filters have filtered a synthetic water that incorporates silica sand to simulate varying levels of natural turbid surface waters.  Particle size distribution analysis was also performed on waters associated with the Tulip and LS filters.  

Preliminary results are suggesting that none of the POU filters are functioning at the full operational levels reported by their respective manufacturers.  The Tulip filters are removing turbidity, TSS, coliforms, and E.coli and are flowing at the expected flow rate of 4-5 L/hour if the filter unit is functioning without a quality control error.  However, several of the Tulip filters are appearing to deteriorate in effluent water quality before the expected 7,000 L end-of-life reported by the manufacturer.  In contrast, the FP, PFP, and LS filters are removing the predicted coliforms and E.coli, as well as turbidity and TSS.  However, none are performing at the expected flow rates.  Laboratory results show that both filters are operating around 0.2-0.5 L/hour.  In addition, the LS filters are not performing at the expected flow rate of 12-15 L/hour, as claimed by the manufacturer.  Continued laboratory results and field measurements of the two clay ceramic filters will be reported in this presentation.  This will allow for further analysis to evaluate the efficacy and efficiency of the four POU filters.

Sarah Ness is a graduate student at the University of South Florida.  She is part of the Peace Corps Master’s International program and is studying Environmental Engineering.  Sarah’s B.S. degree is in Civil and Environmental Engineering from the University of Maryland, College Park and she has water and wastewater treatment experience from working at Gannett Fleming consulting firm.  The focus of Sarah’s research is water and wastewater treatment with an emphasis on sustainability and appropriate technology for developing countries.