JUNE 2023
ON GOOD AUTHORITY Monthly Newsletter for Employees & Families of the Western Virginia Water Authority
On May 25, the Water Authority and Roanoke Gas gathered to celebrate a unique partnership with a ribbon cutting event. This first of its kind project in the Commonwealth of Virginia, will produce commercial quality renewable natural gas (RNG) from biogas produced at the Roanoke Regional Water Pollution Control Plant. The biogas conditioning system will have the ability to create pipeline quality RNG at a design flow of 550,000 cubic feet per day. The pipeline quality RNG will be eligible for renewable credits under the Environmental Protection Agency’s Renewable Fuel Standard program. This new supply source will provide enough natural gas to heat over 500 homes on a cold, winter day. Thank you to all employees involved in bringing this unique project to life!
Biogas Process
Digester Gas Biogas, a mixture of 63% methane and 37% carbon dioxide is produced as a by-product of the anaerobic digestion process in the solids treatment process.
Scrubbers The raw or brown gas is processed through scrubbers where hydrogen sulfide, moisture, siloxanes and VOCs are removed.
Membrane Filtration The biogas is filtered through a three phased Unison membrane system.
Temperature Adjustment Biogas flows through a heat exchanger at 190 oF to remove oil and impurities. The gas then goes through a chiller to reduce the temperature to 50o F-60 o F.
Pipeline Injection
Once all standards are met, nitrogen is used to boost the pressure to 175 psi, and an odorant is added as a safety precaution so leaks can be easily detected by consumers.
Upcoming Dates June: Pride Month June: National Safety Month June 19: Juneteenth Holiday June 23: National Hydration Day June 30: Water and Wastewater Professionals Appreciation Day July 3 & 4: Independence Day Holiday