SoCalGas helps pilot project to convert wastewater solids to RNG
A pilot hydrothermal wastewater processing project, funded in part by Southern California Gas Co., has been selected by the U.S. Department of Energy to receive up to $1.2 million in federal funding.
SoCalGas is part of a consortium, led by the Water Environment & Reuse Foundation, that is conducting the pilot, and the consortium will be required to share the cost at a minimum of 50 percent in order to receive federal funds.
The project will use hydrothermal processing technology to convert wastewater solids into renewable natural gas and liquid fuels. Department of Energy funding is expected to pay for about half of the design and planning of a pilot plant to produce these renewable fuels at the Central Contra Costa Sanitary District near Oakland, California. SoCalGas will help oversee the project’s design and assist in obtaining state and federal regulatory approvals and incentives, the utility said in a news release.
Using water, heat and pressure, the new technology converts waste solids from a wastewater treatment plant into biocrude and methane gas. The biocrude oil replaces fossil oil, providing green fuels with nearly zero net new carbon emissions, while the methane gas can be used in the same ways as fossil natural gas, the utility said.
“SoCalGas and its partners have demonstrated that this process can very effectively convert wastewater solids into renewable natural gas using existing infrastructure, to help replace fossil fuels and reduce greenhouse gas emissions,” said Jeff Reed, SoCalGas’ director of business strategy and advanced technology.
Reed asserted the new technology could have an enormous impact on energy and waste. “Converting the wastewater solids produced by treatment plants in the United States with hydrothermal processing could produce about 128 billion cubic feet of natural gas per year and save treatment utilities $2.2 billion in solids disposal costs,” he said. “A city of one million people could produce more than 600 million cubic feet of natural gas per year, save more than $7 million per year in disposal costs and power nearly 7,000 vehicles per day.”