A new dry anaerobic digestion and renewable natural gas (AD-RNG) facility is being developed at the Napa Recycling and Composting Facility in California, through a public-private partnership between equipment manufacturer BHS (Bulk Handling Systems), waste services operator Napa Recycling and Waste Services and the City of Napa.
The facility will use BHS subsidiary Zero Waste Energy's plug-flow digestion system to recover energy from organic waste collected across the Napa service area, converting it into biogas that can be processed into renewable natural gas (RNG).
The development expands on the site's existing composting operation by capturing greenhouse gas emissions that would otherwise be released and converting them into a usable fuel source.
Annual output is estimated at up to 500,000 diesel gallon equivalents of compressed natural gas, which is sufficient to power around 50 heavy-duty waste collection vehicles per year.
The RNG produced will be used directly to fuel Napa Recycling's own fleet of collection trucks, creating a closed-loop system in which organic waste collected from households and businesses is converted into the fuel used to collect it.
The facility is also designed to generate electricity from RNG should local regulations require refuse and recycling fleets to transition to electric vehicles in future.
Developers say the project will virtually eliminate methane emissions from organic waste disposal in the area, while replacing fossil-derived gas currently used by the trucking fleet.
Dry anaerobic digestion facility to produce renewable gas from organic waste in California
