UASB - Fall 2018

Ian Cullings, Ananya Gangadhar, Cara Smith, Nina Blahut

Abstract:

Since Spring 2017, the AguaClara Upflow Anaerobic Sludge Blanket (UASB) Team has been working on a detailed design of a pilot-scale UASB reactor. A UASB reactor treats wastewater anaerobically and produces biogas as a byproduct. Working towards that goal, the team has created Python code to record the design process and calculations for this AguaClara UASB.

During Fall 2018, the team continued design work on the UASB with the goal of completing a full design. The team also began researching flow patterns through the UASB to optimize treatment and prevent preferential pathways.

Humic Acid - Fall 2018

Matthew Lee, Vanessa Qi, Carolyn Wang

Abstract:

The Fall 2018 Humic Acid Team will focus on testing the effluent humic acid concentration changes as coagulant dosage increases for influent humic acid at 5mg/L, 10mg/L and 15mg/L trials. The new AccuView spectrophotometer will be used to measure the flow absorbance and corresponding species concentrations will be calculated from recorded absorbances with Beer's Law. The team expects to develop better understanding of humic acid concentration changes through the overall experimental system and how humic acid particles interact with clay particles inside the sedimentation model. This research will help AguaClara gain more knowledge of how Natural Organic Matter (NOM) interacts with coagulant in water.

String Digester - Spring 2019

Kiki Lo, Antonio Martinez, Gaby Sibel, Zsofia Szegletes

Abstract:

The objective of String Digester for the Spring 2019 semester was to continue research on revamping a wastewater treatment system to eliminate problems associated with current trickling filters. To improve consistency in wastewater treatment, experiments were conducted using metallic and plastic chains to optimize surface area. The long-term goal of this team is to create an efficient wastewater treatment system that will perform secondary and tertiary treatment on domestic wastewater. These tests involved testing different chain types and synthetic materials for their hydrophillic properties, fabricating and testing reactors for efficiency, and researching biofilm growth to help define design parameters for the construction of a functioning string digester.

StaRS Filter Theory - Spring 2018

Alison Valibuena, Liz Cantlebary, Dylan Vu

ABSTRACT:

Sand filters have historically been used to lower the turbidity of water and are still used in conventional filtration systems. The research in this report is based on the hypothesis that flocs are captured in rings created by filter grains, which implies there is an active filtration zone where empty pores become clogged by the flocs. This active zone moves throughout the bed until there is no remaining space for particles to clog. This research examines the factors that influence the time it takes for the filter to clog. Several key factors affect the failure time including size and density of flocs and were explored through experiments with different coagulant doses and with a constriction placed before the filter.

Trickling Filter - Spring 2018

String Digester — Jillian Whiting, Ben Gassaway, Rosie Krasnoff

ABSTRACT:

The trickling filter subteam's objective for this semester was to identify problems with trickling filters and to provide possible solutions to these problems. The long term goal of the team is to create a novel design for a trickling filter that will perform secondary and tertiary treatment on domestic wastewater in a future AguaClara wastewater treatment plant. After an extensive literature review, two bench scale experiments were conducted. The first test aimed to characterize the hydraulic behavior of a trickling filter and the flow of water through its packing media. The team used this information to identify the areas within the system with the greatest potential for improvements. From this information, the first prototype was built using strings to control flow paths and create a high surface area to volume ratio. Preliminary tests were conducted on the prototype to determine flow dispersion, residence time, and optimal string spacing.

UASB - Summer 2018

Ian Cullings, Isa Kaminsky, Ananya Gangadhar

ABSTRACT:

Since Spring 2017, the AguaClara Upflow Anaerobic Sludge Blanket (UASB) Team has been working on a detailed design of modified, pilot-scale UASB reactor originally proposed in an EPA P3 proposal. A UASB reactor treats wastewater anaerobically and produces biogas as a by-product. Working towards that goal, the team has created Python code to record the design process and calculations for this AguaClara UASB.

Over the summer of 2018, the UASB team's main goal has been to finish a complete design of a UASB wastewater treatment system, and fabricate an influent system. Future teams will work on fabrication of the entire system and testing at the Ithaca Area Wastewater Plant before implementation in Honduras.

Unit Process Analysis pH - Fall 2019

Floc pH — Justin Lee, Jena Rozanski, Rafaella Bruzual

ABSTRACT:

The Unit Process Operations pH subteam wanted to explore the performance of the AguaClara sedimentation tank as a function of pH. Filtration within the sedimentation tank is complex and the performance is often a factor of floc blanket. When the coagulant dosage exceeds a certain amount, the pH probe will be coated with coagulant, leading to inaccurate pH measurements within the plant. Therefore, the team wanted to determine this coagulant dosage and use that value as the constant coagulant dosage for all experimental trials. The team hopes to use this information to uncover new insights on how filtration performance changes in different pH ranges.

StaRS Filter Theory - Fall 2019

Wenjie Lu, Claire Kenwood, Kelly Ly

ABSTRACT:

StaRS (Stacked Rapid Sand) Filtration is crucial to the water treatment process. As one of the last steps in AguaClara’s water treatment, StaRS filters are responsible for removing the last of the unwanted particles. In order to operate effectively under EPA standards, the filters must reduce the turbidity to 0.3 NTU or less. In efforts to better refine the AguaClara filters, variables such as grain size, the height of the active zone, coagulant dosage will be tested in order to increase the failure time. At the beginning of experimentation, the Fall 2019 StaRS sub-team will focus specifically on the grain size.

StaRS Filter Theory - Spring 2019

Barbara Oramah, Lainey Reed, Pablo Alonso Alguacil and Ronya Strom

ABSTRACT:

Stacked Rapid Sand (StaRS) Filtration is the last stage in an AguaClara treatment plant. The filters are used to further reduce the turbidity of water to meet EPA standards of 0.3 NTU or less. As a whole, the StaRS sub-team is working to develop a mathematical model to describe sand filtration. This semester, the StaRS Filter Theory team worked towards running experiments with the three newly constructed StaRS filters with varying sand grain sizes. This research will show the extent to which sand grain size has an effect on filter performance.

String Digester - Spring 2019

Kiki Lo, Antonio Martinez, Gaby Sibel, Zsofia Szegletes

ABSTRACT:

The objective of String Digester for the Spring 2019 semester was to continue research on revamping a wastewater treatment system to eliminate problems associated with current trickling filters. To improve consistency in wastewater treatment, experiments were conducted using metallic and plastic chains to optimize surface area. The long-term goal of this team is to create an efficient wastewater treatment system that will perform secondary and tertiary treatment on domestic wastewater. These tests involved testing different chain types and synthetic materials for their hydrophilic properties, fabricating and testing reactors for efficiency, and researching biofilm growth to help define design parameters for the construction of a functioning string digester.

Ram Pump - Spring 2019

Ching Pang, Cheer Tsang, Alyssa Ju, Iñigo Cabrera

ABSTRACT:

The AguaClara Vertical Ram Pump (ACVRP) is an innovation that will enable water to be pumped from lower elevations to higher elevations using the driving force of falling water. The ACVRP improves on a conventional ram pump design by increasing its space efficiency and decreasing its capital cost. Although a prototype had been built, it did not reach its target pumping efficiency. The goal of this semester was to optimize the ram pump efficiency by finding the necessary forces to open and close the valve at the ideal times.

Ram Pump - Summer 2019

Ching Pang, Alyssa Ju

Abstract:

AguaClara plants contain chemical dosage tanks that require water to make liquid chemical stocks. The AguaClara Vertical Ram Pump (ACVRP) is an innovation that elimantes the need for plant operators to manually displace water up to the dosage tanks. Water is pumped from a lower to higher elevation by harvesting kinetic energy from the treated water flowing out to the community's water distribution system. The design is a modification of the conventional ram pump that allows the waste water to be contained within the pump system due to the inline feature of ACVRP. Compared to a conventional ram pump, the ACVRP is more operator-friendly and requires lower capital cost. Teams from past semesters have determined that the previous version of the ACVRP was inefficient due to a significant amount of head loss. The goal of this summer was to reduce head loss in the design and to determine the efficiency of the improved ACVRP.

Fluoride Automated System - Spring 2019

Fluoride Auto – Dominic Grasso, Melissa Louie, Desiree Sausele, Emily Spiek

Abstract:

The Spring 2019 Fluoride Auto subteam aimed to determine the optimal dosage of polyaluminum chloride (PACl) needed to precipitate fluoride ions out of influent water to meet the World Health Organization’s drinking water standard for fluoride concentration (1.5 mg/L). The team accomplished several fabrication tasks, including lengthening the flocculator used by the Fall 2018 subteam and constructing a new sedimentation tube. The team tested the new apparatus with PACl and red dye to visually determine that it worked properly and that aggregated particles (flocs) were exiting the tube through the floc weir. The team then aimed to run experiments with fluoride but experienced difficulty calibrating the fluoride probe. Upon acquiring a new probe in the future, the team will analyze fluoride removal efficiency using the Langmuir Adsorption Model.

Fluoride - Fall 2019

Fluoride Auto — Sarah Huang, Cindy Jin, Melissa Louie, Emily Yueh

Abstract:

The World Health Organization estimates that globally over one million people face adverse health consequences due to fluoride contamination of drinking water. The current state of fluoride removal technology is not suitable for water treatment plants, and continuous fluoride removal systems do not exist. The Fluoride team aims to develop a cheap and efficient apparatus to reduce ionic fluoride from contaminated water to a safe level. The Fall 2019 team hopes to redesign the flocculation process to optimize the adsorption of fluoride to polyaluminum chloride (PACl) coagulant and the sedimentation process to minimize PACl-fluoride complexes in the effluent, ultimately producing potable water.

Ram Pump - Fall 2019

Ching Pang, Alycia Storch, Payton Hunter

Abstract:

Previous Ram Pump teams have created mathematical models describing velocities, forces, flow rates, headlosses, etc. in the AguaClara Vertical Ram Pump (ACVRP); performed experiments to learn more about what actually happens in the system; and have made redesigns to the setup and ACVRP itself to further improve its efficiency, likeliness to an AguaClara plant, and to increase the ease of assembly and adjustment. This semester the team plans to fabricate a new lab setup that integrates the setup into the work bench for a redesign of the ACVRP, and to further explore ways to improve its efficiency. The team has decided on a new design that eliminates the bottom check valve of the ACVRP and the threaded rod and compression spring that it housed and instead includes an extension spring that will be at the top of the head tank. The extension spring will be connected to a hook on the top of the plate with metal wire rope. It is expected that the functionality and process of the ACVRP will not change but making fine-tune adjustements to the initial and final forces of the spring will be easier to make because there will be easier access to the spring. The team created a materials list for the new parts needed and is currently updating the CAD model to reflect the changes. The team plans to construct the new lab setup and ACVRP design and then to perform experiments as well as improve theoretical equations to further optimize the ACVRP.

Chemical Dose Controller - Spring 2014

Andrea Cashon, Saugat Ghimire, Jeanette Liu

Abstract:

The Chemical Dose Controller team completed the design and fabrication of the single lever arm assembly. This assembly will be utilized in low flow plants that only require a chlorine doser. The new Chemical Dose Controller maintains the same functionality of the previous model. It will also be chemically resistant and require fewer materials, lowering fabrication and shipping costs. The team also created a float valve for the constant head tank that has fewer corrosive metal components and has the floatin line with the orifice. The team has created a new height adjustment system for the constant head tank and a dosing tube air removal system that utilizes a wye channel. Additionally, the entrance tank float was redesigned to be smaller and lighter, for easier and cheaper shipping. Finally, the team created an items catalog that contains every single component - and it’s corresponding McMaster-Carr identification number - used in a Chemical Dose Controller system. This catalog will help future Chemical Dose Controller teams order components and construct new systems.

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Chemical Dose Controller - Spring 2015

Annie Cashon, Christine Leu, Auggie Longo

Abstract:

The Chemical Dose Controller is a device that maintains a constant chemical dose as the plant flow rate changes. After working alongside the foam filtration team in El Carpintero, Honduras this past January, the CDC team has changed the lab set-up to be more reflective of the systems in the field. Specifically, the major head loss element was changed to be vertically-oriented instead of horizontal to decrease the footprint of the CDC system. During the Spring 2015 semester, the CDC team will run a variety of experiments with the new system including head loss testing, determining flow breakpoints, and testing units at stock concentrations. In addition to testing the system through a variety of experiments, several design changes will be looked into this semester. This included tasks such as making the constant head tank from locally available items in Honduras, as well as making the constant head tank chlorine resistant. Finally, the team is compiling a system of equations to convert the CDC system into a modular, packaging item for future shipment. With design changes in mine, a major goal of the CDC team this semester will be to create an assembly manual and parts-list.

Laminar Tube Flocculator - Spring 2015

Luyan Sun, Tanvi Naidu, Kevin Shao

Abstract:

Research on the Laminar Tube Flocculator in Spring 2015 aimed to validate the results obtained by Karen Swetland with the FReTA system and to further investigate factors that affect the overall turbidity removal. The past semester’s team worked to test the new residual turbidity monitoring system, SWaT, in comparison to the FReTA system and to verify that the new system can obtain similar results to those obtained with the old system. However, the actual coagulant tubing size used in the previous SWaT experiment was different from that in the pump control method file. Because of the incorrect input in tubing size, the PACl dosages were not accurate. The Spring 2015 research derived correction factors that would make the previous date usable. Then experiments were conducted in the SWaT system to finish verifying Karen Swetland’s results. Future works includes experiments to determine if there is an optimal floc size which is small enough to combine with small clay particles yet large enough to be separated in the sedimentation tank. Also, future teams should study how dissolved organic matter (DOM) affects the performance of the flocculator and sedimentation tank. These findings will improve the performance of the flocculator and make it more effective for use in water supply.

Grit Removal Innovation Technologies - Spring 2015

Annie Ding, Mary Millard

Abstract:

The current AguaClara plant design requires a large entrance tank to settle out grit particles prior to the flocculator. Grit removal by horizontal flow sedimentation prevents the settling of these larger particles in the flocculator (a phenomenon that has been observed in several AguaClara plants to negatively affect plant flow and operation). The purpose of the Grit Removal Innovation Technologies (GRIT) team is to redesign the current grit settling system by introducing plate settlers prior to the flocculation unit. In doing so, the plan-view area needed to settle out the grit will be greatly reduced, decreasing construction costs and overall AguaClara plant size. This paper outline the GRIT team’s process exploring plate settler design options that act either as sedimentation units only, or as combined flocculation and sedimentation units.

There is no other literature on the topic of designing such grit removal systems, and not all of the relevant parameters are well understood. The team’s design process has therefore been based on a series of reasonable assumptions and equations currently used in flocculator and sedimentation tank design. Many constraints (detailed in this report) were found to impact the design of the grit removal unit, including grit particle “roll-up” effect, optimal head loss, optimal unit length. In addition to the design of the grit removal unit itself, this team explored the corresponding designs of rapid mix, linear flow orifice meter (LFOM) placement, and coagulant dosing, in order to create a fully integrated system.

Over the course of the Spring 2015 semester, the GRIT team has developed three potential grit removal designs, created visual mock-ups of each, and even sent a detailed design of the best iteration to Honduras for implementation in a small-scale plant. The first iteration, a combined grit removal and flocculator system, integrated grit removal capabilities into the flocculator baffles, but it was rules out early in our design process due to the potential loss of coagulant to grit (as coagulant would be dosed before grit would be removed), inefficient use of space, and construction and cleaning impracticalities. The second and third iterations were both based on the idea of creating a tightly packed series of plate settlers (we call this a Grit Removal Unit, or GRU), analogous to the ones used in current sedimentation tank design, used before the flocculation process and designed to settle out grit specifically. The second iteration placed this GRU inside the entrance tank, while the third iteration placed it within the first flocculator channel. After analyzing space need, flexibility of design, and capacity for rapid mix/coagulant dosing integration, the third iteration was chosen as the optimal grit removal design and is well on its way to being constructed in Honduras!

Foam Filtration Pore Size - Spring 2015

Lotta Van Leeuwen, Tianchen Yu, Caroline Caglioni

Abstract:

Abstract unavailable for this team for this semester.

Please note, the final report is not available for this team for this semester and the Final Presentation is linked instead.