Water Remediation Lab
An example home water purification system—a Brita water pitcher that uses activated carbon in its built-in water filter.Copyright (left) 2006 Lee J. Haywood, Wikimedia Commons, (right) 2012 Wikimedia Commons http://en.wikipedia.org/wiki/File:Brita_kettle.jpg http://en.wikipedia.org/wiki/File:Brita_Filter.png
Students measure the effectiveness of water filters in purifying contaminated water. They prepare test water by creating different concentrations of bleach (chlorine-contaminated) water. After passing the contaminated water through commercially available Brita® water filters designed to purify drinking water, students determine the chlorine concentration of the purified water using chlorine test strips and measure the adsorption of chlorine onto activated carbon over time. They graph and analyze their results to determine the effectiveness of the filters. The household active carbon filters used are one example of engineer-designed water purification systems.
Environmental and chemical engineers add small amounts of chlorine to water during treatment processes because chlorine is a known disinfectant. However, too much chlorine in drinking water can result in adverse health effects for humans. A remedy to remove excess chlorine and other contaminants from drinking water is activated carbon, which is charcoal designed by engineers for both large and small scale water purification use. Understanding the adsorption of contaminants in systems such as activated carbon over an extended time period is vital for environmental engineers to produce more efficient and safe purification models.
After this activity, students should be able to:
- Apply their engineering knowledge to a commercially available water purification system.
- Describe how activated carbon in water purification filters removes contaminants.
- Determine the efficiency of household water purification systems in chlorine removal and apply that knowledge to other contaminants.