Tyson Foods, Inc. (“Tyson”) is the world’s largest supplier of protein, operating poultry, swine, and beef processing plants. Wastewater from Tyson’s processing plants is treated at wastewater treatment plants owned and operated by Tyson. Tyson’s 100 wastewater pre-treatment and full-treatment plants treat over 100 million gallons of water a day.

Tyson first began managing the biogas emissions from its wastewater treatment facilities in December of 2000 and early 2001, with the installation and operation of covers for the anaerobic lagoons at four of its wastewater treatment facilities throughout the Midwest. Initially, the captured biogas was flared at all four sites, converting the methane to less harmful CO2. This covering and flaring represents Stage 1 of the emission reductions project. At each of the four wastewater treatment facilities, the existing anaerobic lagoons were covered with a gas-tight high density polyethylene (HDPE) material.  Centrifugal, low-pressure biogas blowers were installed to move the biogas through the gas processing system for eventual flaring.

Stage 1 results in significant reductions of anthropogenic GHG emissions. As a result of Tyson’s capture and flare of fugitive gas (methane) at its wastewater treatment facilities, direct emission reductions have been achieved. All wastewater treatment now occurs primarily in covered anaerobic lagoons. Gas collected from the anaerobic lagoons is captured and flared. This reduces the GHG impact of the facility, by means of the destruction of CH4.

Stage 2 of Tyson’s emission reduction project involves tying in the onsite boilers to the biogas collection system, which involves the installation of more powerful centrifugal blowers to move the biogas to the packing plant. Whenever possible, the biogas is utilized in the boilers, displacing the fossil fuels that would be consumed in its place, thus reducing the CO2 emissions from fossil fuel combustion. For various reasons, it is not always possible to utilize the biogas at all times. Because of this, the flares from Stage 1 remain an integral part of the system, continuing to destroy the CH4 that would otherwise be vented during these downtimes.