Bringing In Biogas

Geomembrane Technologies Inc.

Alternative energy is becoming increasingly popular as the costs of water and energy continue to rise and more pressure is put on corporations to demonstrate environmental sustainability. Pinnacle Foods is an example of a progressive company that has invested in a waste-to-energy initiative to transform what would otherwise be wasted into a valuable resource that saves money—and the environment.

The Customer

Pinnacle Foods is a producer of quality branded food products, including syrups, sauces and salad dressings. The company’s products are widely consumed and can be found in 85% of American households. Pinnacle is committed to reducing its carbon footprint and energy use, always looking for ways to improve its manufacturing operations.

The Opportunity

When Pinnacle Foods acquired new salad dressing businesses, its plant in St. Elmo, Ill., needed to expand its facility to accommodate additional flow. As part of this expansion, its wastewater treatment plant needed to be upgraded. Pinnacle chose to introduce anaerobic digestion technology, and with this came the opportunity to convert waste into energy.

As organic matter breaks down in the anaerobic digestion process, biogas is naturally released as a byproduct. Biogas can be used in engines and combined heat and power units for electricity and heat, and in boilers for process heat and steam.

But when wastewater treatment tanks and lagoons are left uncovered, biogas—along with all the money-saving potential that comes with it—disappears into thin air. Moreover, greenhouse gas emissions enter the atmosphere, damaging the ozone layer and, consequently, human health.

By capturing the biogas, Pinnacle Foods could harness the energy to offset costs and become more environmentally friendly. It just needed the right gastight cover.

The Solution

Geomembrane Technologies Inc. (GTI) was selected to design and install a gas collection cover for Pinnacle Foods as part of its wastewater treatment expansion project. GTI created a patented, custom-made 95-ft (29-m)-diameter insulated cover to resist elements and weathering.

GTI’s gas collection cover was made with strong, long-lasting materials to resist tears, punctures, chemicals and ultraviolet rays. The gastight cover includes various accessories to facilitate operator inspections and maintenance. It is engineered to safely support foot traffic.

The Results

The cover that GTI engineered for Pinnacle reliably collects biogas from the anaerobic digester, preventing harmful greenhouse gasses from being released into the atmosphere. The system can generate 67,000 cu ft/day (1,900 cu m/day) of biogas, which is utilized in a new boiler at the treatment plant, helping to heat the digester to the proper temperature. The insulation provided by the cover also helps the digester retain heat more efficiently, so even less energy needs to be produced.