By Ted Robbins, Court 1
Board Vice President Joe Khoury was thrilled when the Village Green implemented California’s new law mandating household food waste be recycled. As Supervising Scientist at LA County’s Sanitation District, he knows exactly what happens to that
waste. “We collect it and convert it to fuel for cars,” he says.
waste. “We collect it and convert it to fuel for cars,” he says.
Organic waste (any material that is biodegradable and comes from living organisms like plants or animals) dumped in traditional landfills decomposes and releases methane into the atmosphere—a much more potent greenhouse gas than carbon dioxide (CO2). The state wanted to slow global warming by sending biodegradable waste to what are called anaerobic digestion facilities. Food waste has been collected from restaurants this way for years, but in 2022, State Bill 1383
mandated residential diversion as well.
Here’s how it works: a company picks up the waste, grinds it into a slurry and delivers that mixture to the enormous digesters at the wastewater treatment plant where he works—huge sealed tanks where sewage sludge is heated and stirred. “They are each the size of one of the buildings at Village Green... and we have 24 of them.”
Anaerobic digestion of biodegradable garbage produces methane gas as it would in a landfill but in this case, the gas is contained and used to power trash trucks and district vehicles. “By diverting our organic waste to the wastewater treatment plant and using it to produce biofuel, that fuel gets burned and eventually produces CO2. But that biofuel replaces gasoline that would’ve gotten burned and produce CO2. So, you reduce the total emissions.”
Khoury says people get confused between food waste and garden composting. The anaerobic decomposition rate, he says, is much faster than composting garden waste: “Branches from trees take a while to decompose. Because food waste breaks
down so rapidly, it can’t be handled in landfills but it’s perfect for the wastewater treatment plants.” That’s why we’re using food waste bins in each trash area. It’s
not perfect, but it’s a positive step in fighting climate change.
mandated residential diversion as well.
Here’s how it works: a company picks up the waste, grinds it into a slurry and delivers that mixture to the enormous digesters at the wastewater treatment plant where he works—huge sealed tanks where sewage sludge is heated and stirred. “They are each the size of one of the buildings at Village Green... and we have 24 of them.”
Anaerobic digestion of biodegradable garbage produces methane gas as it would in a landfill but in this case, the gas is contained and used to power trash trucks and district vehicles. “By diverting our organic waste to the wastewater treatment plant and using it to produce biofuel, that fuel gets burned and eventually produces CO2. But that biofuel replaces gasoline that would’ve gotten burned and produce CO2. So, you reduce the total emissions.”
Khoury says people get confused between food waste and garden composting. The anaerobic decomposition rate, he says, is much faster than composting garden waste: “Branches from trees take a while to decompose. Because food waste breaks
down so rapidly, it can’t be handled in landfills but it’s perfect for the wastewater treatment plants.” That’s why we’re using food waste bins in each trash area. It’s
not perfect, but it’s a positive step in fighting climate change.
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