Grantee Research Project Results
Final Report: Environment and Community-Friendly Wastewater Treatment
EPA Grant Number: SV839486Title: Environment and Community-Friendly Wastewater Treatment
Investigators: Richardson, Ruth E.
Institution: Cornell University
EPA Project Officer: Page, Angela
Phase: II
Project Period: April 1, 2019 through March 31, 2021 (Extended to March 31, 2023)
Project Amount: $75,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2019) Recipients Lists
Research Category: P3 Challenge Area - Safe and Sustainable Water Resources , P3 Awards
Objective:
Our project objectives for Phase II built on the Phase I design of a household-scale UASB. Our specific objectives were:
- Improving the influent dosing system and floatables removal
- Characterizing startup and performance of gravity-powered UASB reactors
- Determining appropriate options for effluent post-treatment and biogas utilization
- Iterating designs and installing and testing a distributed UASB reactor in Honduras or Puerto Rico
Summary/Accomplishments (Outputs/Outcomes):
The UASB research team successfully designed, fabricated, and installed a household-scale UASB reactor at the Ithaca Area Wastewater Treatment Facility (IAWWTF). The team also designed a simple membrane reactor for further treatment of UASB effluent to remove additional contaminants as well as the dissolved methane in the effluent. Significant design work was conducted to create an effective gas capture and metering system, a method to remove fats, oils, and grease that may accumulate on the water surface, and an intermittent influent feed system that minimizes preferential flow through the reactor. A complete manual and fabrication guide have been developed. We showed that the simple, pulse-based delivery system was able, with a 10-hour retention time to remove ~40-60 % of the COD, and the polishing membrane reactor removed an additional 40% (including >99% of the dissolved methane) and 50% of the ammonia. The UASB reactor is stably producing 20-40 L per day of biogas while treating ~300 L of sewage per day. The inexpensive (<$1500) UASB-polishing reactor system is powered solely by gravity and its simple design was robust against breakage. In the years of operation, no repairs were needed and the reactor was only offline due to other factors (the Covid-19 shutdown). All parts of the reactors can be purchased at a hardware store and simple tools (e.g. hand drill) are needed to construct the reactors.
Figure 1: Photo showing the design and construction of the tipping bucket for pulsed delivery of sewage into the UASB in 4 L doses.
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Figure 2: Photo showing the design and construction of the tipping bucket for pulsed delivery of sewage into the UASB in 4 L doses.
Figure 3 showing details of the design elements of the UASB reactors. Effluent adaptiation is were the effluent leaves the reactor. The sludge lines are used to drain the excess granules from the top of the granule bed.
Figure: Top: Representative data for the Organic Carbon levels (COD) in influent and effluent of the UASB; Bottom: example biogas production by the UASB at the end of the EPA P3 project. Note that the system was very cold as it was Ithaca winter, and the heat tape was not working. This would cause subdued activity compared to tropical temperatures.
Conclusions:
In summary, we have shown that a small gravity powered UASB can operate robustly without mechanical failure for years on end. The low cost and fact that UASBs perform even better when fed stronger waste, we propose that our UASB tipping bucket design would best be optimized by focusing blackwater. We’ve learned that separating blackwater, which is ~5x stronger than mixed wastewater/sewage, is a custom common in Puerto Rico on site water systems - in fact Dr Richardson learned that in Puerto Rico when they say “wastewater” they are talking about blackwater (toilet/bathroom water). They don’t usually mix with gray water unless they are in a city.
Journal Articles:
No journal articles submitted with this report: View all 14 publications for this projectSupplemental Keywords:
Membrane bioreactorRelevant Websites:
Progress and Final Reports:
Original AbstractP3 Phase I:
Climate & Community Friendly Wastewater Treatment | 2018 Progress Report | Final ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.
Project Research Results
- 2021 Progress Report
- 2020 Progress Report
- 2019 Progress Report
- Original Abstract
- P3 Phase I | 2018 Progress Report | Final Report