FORCE MAIN GAS BINDING
Pumping and conveying of wastewater from end user through the collection system towastewater treatment plants can result in negative conditions including gas binding, blockages associated with fats, oils and greases (FOG), and system corrosion. There may be other contributing conditions, but these factors appear to be the greatest contributors to O&M costs including energy consumption, maintenance costs, and Sanitary Sewer Overflows (SSOs).
A collection system line is a unique conveyance system. The transfer of wastewater can result in the release of gases such as O2 Oxygen, CO2 Carbon Dioxide, N2 Nitrogen Gas, H2S Hydrogen Sulfide, CH4 Methane, VOCs Volatile Organic Compounds, and VOSCs Volatile Organic Sulfur Compounds among others. Some of these gases are drawn into the system through pumping and ventilation, while others are generated within the system either chemically or biologically. These gases can result in the development of gas binding in the system, especially with the utilization of calcium nitrate, as well as contribute to odors and corrosion.