Boulder’s wastewater treatment plant started up a new $3 million UV disinfection system purify the city’s wastewater. Flows are 12.5 million gallons per day of wastewater. Costs are comparable to the previously used chlorine gas/sulfur dioxide chemicals previously employed, however the safety and environmental aspects of UV are dramtically better than the chemicals.
The UV does not create disinfection byproducts that may be harmful to aquatic life, reduces the carbon footprint of the plant by elimianting the need to transport the chemicals and improves the safety and security of the facility related to the storage and handling of the chlorine and sulfur dioxide. A failure of one of he 2,000 pound storage cylinders could result in an extensive evacuation of people for a couple of miles around the plant. In total, the plant stored upwards of six tons of the toxic chemicals on site at any given time. Hazard response teams were on call in case of any kind of accident.
UV wastewater disinfection has become an important technology. Most new facilities constructed have dopted UV. Different kinds of UV systems exist. Boulder uses a low-pressure, high-output UV system.
Other technologies such as advanced oxidation or combining UV with ozone water treatment or hydrogen peroxide can potentially remove trace organics or small carbon products. Boulder has not considered those technologies yet, but is leaving its options open. UV, ozone and other related technologies are changing the way water and wastewater are treated. These technologies reduce the formation of dangerous byproducts, improve safety and security at the facilities and provide better treatment.