Three fourths of all people in Haiti lack access to a safe toilet, contributing to frequent diarrheal illness, devastating cholera outbreaks and high childhood mortality. The sustainable sanitation organization Sustainable Organic Integrated Livelihoods (SOIL) currently provides low cost sanitation to slum neighborhoods in Haiti by collecting feces from urine diverting toilets in buckets and composting it into organic fertilizer. One issue with their current system is that each bucket must be cleaned with a power washer before it can be re-used, leading to a lot of water use and wastewater that needs to be treated before disposal. The goal of this project is to develop a compostable bucket liner using local agricultural or cardboard/paper waste products (and a system for making it) that will facilitate bucket cleaning and save water.
SOIL’s ecological toilets separate urine and feces into different containers (figure 1). The urine falls into a jug and is managed by the user. The feces are collected in a standard 5 gallon bucket and are covered after each use with a dry organic powder made from sugar cane bagasse and peanut shells called “bonzode” or “good odor”.
Figure 1: A SOIL toilet and a schematic of a slightly revised design from MSD team P19414
The bucket is picked up weekly or twice a week, covered, and taken to a compost site. At the site, the contents are manually emptied onto a compost pile which is then covered with more bonzode (figure 2). The buckets are then taken to a washing station where they are power washed and dipped in an antiseptic solution. The wash water is collected into a septic system.
Figure 2: Collection and dumping
These toilets already save a lot of water because they do not require flushing, but the process for cleaning the buckets and returning them to users is still somewhat water intensive. SOIL has measured it at about 34 gallons per bucket, which represents about 187 toilet uses. SOIL serves 1100 households. If these houses had flush toilets instead of ecological toilets, they would use an additional 21 million gallons of water (see https://www.oursoil.org/water/).
Still, SOIL would like to minimize its water use even further. One idea for facilitating cleaning is lining the buckets with a compostable liner so that the contents can slip cleanly and easily onto the compost pile without leaving residues that need to be sprayed off. Various agricultural, food processing, and industrial wastes such as sugar cane bagasse, peanut shells, shredded cardboard, rice hulls, etc. could potentially be used to develop a liner. Local food waste composting companies may also have interest in these liners.
Your team is tasked with developing the liner and designing a manufacturing system to make it.
Project Title: SOIL Compostable Bucket Liners
Project Number: P20415
Project Family: Sustainable Organic Integrated Livelihoods (SOIL)
Start Term: Fall 2019
End Term: Spring 2020
Faculty Guide: Terry Wright
Primary Customer(s): Sarah Brownell
Sponsor (financial support): SOIL
Project Manager, Communicator
Project Manager, Purchasing, Assistant Confluencer
Lead Process Engineer, Facilitator, Haiti SME
Lead Product Engineer, Lead Confluencer
Facilitator, Note Taker, Lead Trelloer, Materials SME
|Sarah Brownell||N/A||Faculty Advisor / Customer|
Work Breakdown: By Phase
MSD I & II
Customer Handoff & Final Project Documentation (Verification & Validation)
Work Breakdown: By Topic
Presentation & Dissemination
Pugh Concept Selection
Facility Layout Manuals
- Guide: Terry Wright
- Customer: Sarah Brownell
- Sponsor: Sustainable Organic Integrated Livelihoods (SOIL)
- Subject Matter Experts: RIT Packaging Department
Compostable Bag Used in Testing. Retrieved from https://www.amazon.com/Biodegradable-Recycling-Degradable-Compostable-Wastebasket/dp/B07KS8VFQL
Composting. (n.d.). Retrieved from https://www.bpiworld.org/Composting
Helmenstine, Anne Marie, Ph.D. (2020, February 11). The Definition of Hydrophobic With Examples. Retrieved from https://www.thoughtco.com/definition-of-hydrophobic-605228
Painter, Sally. (2006/2020) Benefits of Using Biodegradable Plates. Retrieved from https://greenliving.lovetoknow.com/Benefits_of_Using_Biodegradable_Plates
Woodford, Chris. (2008/2018) Bioplastics. Retrieved from https://www.explainthatstuff.com/bioplastics.html.