Fluoride - Spring 2018

Philip Akpan, Tigran Mehrabyan, Desiree Sausele, and Victoria Zhang

Abstract

The Fluoride subteam seeks to develop a sustainable, inexpensive fluoride removal system for implementation in upcoming AguaClara plants located in India. Using the apparatus developed by previous semesters, the team continued running experiments testing how various concentrations of PACl affect fluoride removal. However, complications with the ability to measure fluoride concentrations required the team to shift its goals to designing a lab scale, gravity-powered system. The team finalized a design and completed construction of the new, electricity-free apparatus. The team plans to run experiments to test its fluoride removal capabilities after ensuring that there are no remaining water leaks.

UASB - Spring 2018

Zac Chen, Jennifer Jackson, Ian Cullings, and 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. This document serves as a master guide for the design process.

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.

Ram Pump - Spring 2018

Maile McCann, Will Lopez, and Steven Lopez

Abstract:

The goal of the Ram Pump subteam is to optimize the pumping efficiency of the hydraulic ram pump, where efficiency is measured in energy of water entering the pump over the energy of the water pumped. The hydraulic ram pump pumps clean water through the plumbing system of an AguaClara water treatment plant, which provides treated water for use in the chemical dosing system as well as sinks and toilets, and saves operators time and energy transporting treated water up by hand. The ram pump system is entirely electricity-free.

A major goal of Spring 2018 was to examine maximum energy efficiency. The value of calculating experimental energy efficiency is that the team is then able to compare the values to calculated theoretical energy efficiency. From there, we can exclude terms in the theoretical calculations to determine the main contributors to inefficiency.

This manual outlines procurement, fabrication, testing, and cleaning of the current hydraulic ram pump model as of Spring 2018.