Green Club 2016

Wastewater Treatment Design Challenge

Background

You are working for “Engineers Without Borders”, an international non-profit humanitarian organization established to partner with developing communities worldwide in order to improve their quality of life. Because of a lack of good laws and poor government, the people in a small town of Rancho Grande in Nicaragua are continuously exposed to pathogens in their drinking water. This is causing many people to get sick. Your task is to build and install a water filtration system for the towns’ children’s feeding centers.

Because “Engineers Without Borders” is a non-profit organization, you need to find a way to create a safe and clean water supply at minimal cost. The water that needs to be treated includes water from toilets, showers, sinks, and wash tubs. In fact, it will include all the water that goes down the drains in the Rancho Grande’s homes, schools, shops and industries.

The Challenge

Build and test a model (prototype) of a wastewater treatment system that adequately removes unwanted solids and visible matter. (This will be the first round of treatment.) You will not need to treat the solids that you remove from solution. Although wastewater treatment normally includes steps to kill germs, you will not need to include disinfectant in your treatment design because the synthetic wastewater you will be using will not contain disease-causing bacteria.

Design Criteria and Constraints

  • The system must be able to treat one liter of synthetic wastewater, which will be provided.
  • The treatment should lower the turbidity of the wastewater.
  • The treatment should not add any new contaminants to the water.
  • The cost of the system should be as low as possible yet provide effective treatment.
  • The system must pose no hazards to users or observers.
  • The system should be easily transported and with easy set up and take down.
  • The model is limited to a maximum of five separate containers for filtration and/or storage.
  • Your model must fit within a 1m2 area.

Parts List and Cost

Item / Cost per Item ($) / Quantity / Cost per item
Plastic Soda Bottle / 0.05
Tubing / 1.50/m
Straight Connector for tubing / 1.8
T connector for tubing / 1.0
Duct tape / 0.15/m
Stopper / 0.15
Screen -10 cm 2 / 0.75
Gravel – 100g / 0.50
Sand – 100g / 0.75
Bucket / 2.00
Coffee filter / 0.10
Clasp/binder/clamp (any type of fastener) / 0.10
Cheesecloth/cotton 15 cm 2 / $0.50
Charcoal 100g / $0.75
Popsicle sticks / $0.50
Other (must be pre-approved)
Total Cost