Odor mitigated & biogas collected by custom-designed product
HP Hood LLC is one of the largest branded dairy operators in the United States, with 13 plants across the country. It has been producing high-quality dairy products for more than 160 years.
HP Hood’s plant in Winchester, Va., was undergoing a planned expansion to its wastewater treatment system to keep pace with consumer demand. The dairy company needed a reliable cover solution for its new anaerobic wastewater treatment system.
Geomembrane Technologies Inc. (GTI) designed, fabricated and installed a floating gas collection cover system as part of HP Hood’s wastewater treatment upgrade. This membrane cover was custom-designed to fit HP Hood’s new anaerobic digester, which treats wastewater from the milk processing facility. GTI also installed process piping inside the digester, which is integral to its proper operation.
Biogas is a naturally occurring gaseous fuel produced during the anaerobic digestion process. The gas collection cover provides the opportunity for the plant to safely collect this valuable biogas and use it in plant operations in the future, if it wishes. The cover also prevents the diffusion of odor vapors and provides insulation to protect against process heat loss and cold temperatures.
This is the third expansion that GTI has helped facilitate at HP Hood’s Winchester plant. GTI was originally selected to install a gas collection cover system for the dairy company’s anaerobic digester at the turn of the century and, as a result of plant expansion, later returned to install a second cover system. As part of the most recent expansion, HP Hood’s oldest anaerobic digester was converted to an aerobic sequencing batch reactor, eliminating the need for one of the three covers. Two GTI covers remain on site and continue to deliver operational savings.
The gas collection cover that GTI created specifically for HP Hood addresses common odor concerns related to the treatment of dairy wastewater. By securely covering the digester with a gastight cover system, HP Hood has taken proactive steps to protect the dairy company’s image in the City of Winchester.
Furthermore, the insulation value of the GTI cover system improves efficiency for the anaerobic digestion process, which helps the plant meet environmental regulations and avoid costly fines. In addition to controlling odors and maintaining temperature, the cover also collects valuable biogas, which can be burned in a combustion flare or used on site to help reduce energy costs if desired.
The gas collection cover is safe for operators to walk across and includes several access hatches. These two cover features simplify routine maintenance and sampling at the wastewater treatment plant.
GTI’s versatility was shown throughout this project. From customizing the gas collection cover system to HP Hood’s unique requirements to installing fundamental process piping to performing maintenance on the existing cover system at the dairy processor’s site, all the challenges faced were overcome and completed—on schedule and on budget.