@article{portiolli_rogers_beckwith_tsai_ole-moiyoi_wilson_reyes_2021, title={Development of trash exclusion for mechanized pit latrine emptying}, volume={8}, ISSN={["2053-1419"]}, url={https://doi.org/10.1039/D1EW00383F}, DOI={10.1039/d1ew00383f}, abstractNote={The trash-excluding attachment (Excluder) can be connected to a custom vacuum (such as the Flexcrevator), a vacuum truck, or a sludge pump. The system allows the mechanized emptying of pit latrines with high levels of trash without manual “fishing”.}, journal={ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY}, author={Portiolli, Giovanna F. and Rogers, Tate W. and Beckwith, Walter and Tsai, Jocelyn and ole-MoiYoi, Payan and Wilson, Noel and Reyes, Francis L., III}, year={2021}, month={Aug} }
 @article{sisco_rogers_beckwith_chipeta_holm_buckley_de los reyes_2017, title={Trash removal methods for improved mechanical emptying of pit latrines using a screw auger}, volume={7}, ISSN={2043-9083 2408-9362}, url={http://dx.doi.org/10.2166/washdev.2017.106}, DOI={10.2166/washdev.2017.106}, abstractNote={Trash in pit latrines is one of the largest challenges facing pit emptying technologies, including the powered auger (the Excrevator), developed for improved emptying in lower- and lower-middle income countries. This study focused on two trash removal methods in conjunction with pit emptying by the Excrevator: (1) simultaneous removal of trash with sludge and (2) manual trash removal prior to sludge removal. Simultaneous removal was tested by adding to the inlet of the Excrevator system two cutting heads designed to reduce the size of trash particles before entering the pipe and auger. Laboratory testing indicated that the auger will not provide the rotational speeds necessary for proper maceration of fibrous materials such as clothing, indicating that a separate maceration unit with higher rotational methods may be more appropriate. Four manual trash removal mechanisms were designed to improve on existing manual trash ‘fishing’ tools such as iron rods with fixed hooks. Two of these tools (the ‘claw’ and the ‘hook’) showed promising laboratory results and were subsequently field tested in Mzuzu, Malawi. Both tools proved more efficient than the current tools used in the field and have potential for use in Malawi.}, number={1}, journal={Journal of Water Sanitation and Hygiene for Development}, publisher={IWA Publishing}, author={Sisco, Tracey and Rogers, Tate and Beckwith, Walt and Chipeta, Willy and Holm, Rochelle and Buckley, Christopher A. and de los Reyes, Francis L., III}, year={2017}, month={Feb}, pages={85–91} }
 @article{rogers_reyes_beckwith_borden_2014, title={Power earth auger modification for waste extraction from pit latrines}, volume={4}, ISSN={["2043-9083"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84896480247&partnerID=MN8TOARS}, DOI={10.2166/washdev.2013.183}, abstractNote={The extraction auger was developed to meet the need for a low cost, effective method to empty pit latrines in difficult to access locations. The basic design consists of a motor that rotates an auger inside a pipe, lifting waste from a pit and depositing it into containers through a wye fitting at the top of the device. Laboratory testing of the auger showed increases in flow rates with increasing auger rotational speed and waste viscosity. An auger with an external hydraulic drive was capable of lifting dairy waste over 2.5 m, at flow rates of over 125 liters per minute. Field-testing showed the equipment was effective at lifting medium viscosity wastes containing a mixture of liquid and solid material. However, the auger was not effective in removing low viscosity, liquid waste that would flow backward down the auger reducing lifting efficiency. The auger was capable of drilling into dense solid waste, forming a ‘posthole’ in the waste. However, since the dense solid waste would not flow towards the auger intake, actual waste removal from the pit was limited. Improved methods are needed to mix liquid and solid waste in pits prior to removal with the extraction auger or other technologies.}, number={1}, journal={JOURNAL OF WATER SANITATION AND HYGIENE FOR DEVELOPMENT}, publisher={IWA Publishing}, author={Rogers, Tate Weston and Reyes, Francis L., III and Beckwith, Walter J. and Borden, Robert C.}, year={2014}, pages={72–80} }