CR&R breaks ground on California AD facility

By Katie Fletcher | July 03, 2014

CR&R Environmental Services, a recycle and waste collection company in Southern California, entered into the construction phase of its anaerobic digestion (AD) facility in Perris, California. The project is fully permitted for four phases, the first phase converting over 80,000 tons per year of municipal organic wastes into 1 million gallons of renewable natural gas (RNG). The following three phases will convert over 320,000 tons of organic wastes into RNG and generate the energy equivalent of 4 million diesel gallons.

In the United States,  AD projects have been prevalent in the treatment of manure at dairy farms. Now the technology is moving into the conversion of organic waste. Mike Silva, civil engineer and project manager for CR&R, believes there will be 20 to 30 similar facilities in California alone because of the need to dispose of organic waste in a more environmentally friendly way. “Right now organics are going towards the landfill and producing methane gas,” Silva said.

According to Silva the two options to keep organic waste out of the landfill are to compost the material or utilize digesters like CR&R is doing. CR&R chose AD as the route to take because the organic waste has three key elements that need to be captured, including energy, emissions and nutritional value of the organic fertilizer. “Our advantage when it goes to an AD is that we capture all three things,” Silva said. “No other alternative for organics management solves all three of those issues.”

CR&R serves more than 2.5 million people and 50,000 businesses throughout Orange, Riverside, Los Angeles, San Bernardino and Imperial counties. The AD facility will take in green waste and food waste from their municipal waste collection customers. Before the waste is fed to the digesters it will be sorted again for quality control to provide conditioned organic material to the digesters. “We are dealing with everyday people and they’ll throw things in there that shouldn’t be,” Silva said. “We already have one of our big cities, Costa Mesa, under contract to give us their organic waste, so that is exciting.”

The created biogas will be upgraded to produce RNG, which will be used to fuel about 70 CR&R collection vehicles. “Running our trash trucks on renewable natural gas makes our system really unique,” Silva said. “We’re going to use all of our own gas initially.”

Subsequent phases will enable CR&R to inject into the Southern California Gas pipeline. The gas clean-up system is supplied by Greenlane Biogas, based in New Zealand. This system will use water scrubbing and other advanced technologies to clean raw biogas to required specifications for the vehicle fuel and pipeline injection.

The core of the technology at the Perris facility comes from Eisenmann, a German provider of biogas technology, who has installed over 90 biogas plants worldwide. “This is their biggest project in the world,” Silva said.

Eisenmann’s High Solids Anaerobic Digestion system employs a continuously fed, horizontal plug flow design which allows for maximum biogas production, a high degree of consistency and full automation.

Constructing the largest AD facility to produce RNG from municipal organic waste coincides with CR&R’s goal of looking for innovative ways to collect and manage waste. The Perris facility anticipates completion of phase one in the first quarter of 2015. “It’s a good challenge,” Silva said.