Joining forces

Features - Organics Supplement: Processing

The ReSource Center in Santa Barbara County, California, serves as a model for the successful development of a one-of-a-kind solid waste recycling facility.

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October 4, 2021

Photos provided by the County of Santa Barbara

For the past 15 years, the county of Santa Barbara, California, has been making strides on the development of a $130 million solid waste recycling project.

Planning first began for the massive undertaking—which would soon be known as the ReSource Center—in 2007 when the County Board of Supervisors sought to look into new ways to decrease landfill dependency and increase recycling.

“In Santa Barbara, we generate about 9 pounds [of waste] per capita per day, which is a lot higher than the national average. That’s because this waste shed covers just southern Santa Barbara County, which is really affluent, and the more affluent communities are, the more trash they generate,” says Carlyle Johnston, a project leader for the County of Santa Barbara (COSB).

Since the development plans for the project were first established, Johnston says the Santa Barbara County Public Works Department immediately started performing environmental impact reports and negotiating contracts, while also having to battle a lawsuit filed by the Gaviota Coast Conservancy regarding concerns over environmental impacts.

“We started with going to the community and defining what the criteria and the goals of a project like this would be. We came up with things like local control, flexibility, reducing landfill dependency, increasing recycling, mitigating more of the environmental impacts of trash, those types of things,” Johnston says. “During that process, we then hired Alternative Resources Inc. to help us develop a RFQ (request for qualifications) and then eventually a RFP (request for proposal) and spent a couple years [working on] that.”

By 2012, the county had made the decision to contract Newport Beach, California-based Mustang Renewable Power Ventures, through affiliate MSB Investors, to develop the project.

“[COSB] spent a lot of time doing community outreach and talking to environmental nonprofit groups,” says Johnston. “The biggest challenges we faced during development and undergoing environmental impact reviews was just getting through the process and getting everyone on board.

“We had four cities sign on to the project with us, so having multiple cities and the county government working together can be really, really challenging. … Every time we had a change, I would have to go back to each individual city and the county and do a presentation again—it was a long process.”

MAKING A PLAN

After sifting through a few different plans and gauging public interest on each, the county ultimately settled on the ReSource Center, a concept designed to address new mandates by increasing recycling, composting organics that are currently being landfilled and reducing the landfill’s carbon footprint.

“The [ReSource Center] was consistently seen as the most viable and the most desirable by the general public, elected officials, kind of everybody,” says Johnston.

The unique facility—a first of its kind in California—will be housed at the county’s Tajiguas Landfill and will include a material recovery facility (MRF), an anaerobic digester (AD), a compost management unit, mulching operations and an upgraded landfill gas (LFG) collection system all on the same campus.

The first phase of the project, which began in 2019, was the construction of the MRF. Operated by Santa Barbara-based MarBorg Industries, the facility processes municipal solid waste (MSW) collected from the area, recovering recyclables and organics.

The ReSource Center accepts solid waste from the South Coast and Santa Ynez Valley areas of Santa Barbara County, including the unincorporated communities in these areas, and from the California cities of Santa Barbara, Goleta, Solvang and Buellton.

“[Mustang Renewable Power Ventures] pitched to the county of Santa Barbara to consider other alternatives than conventional recycling,” says Wilfred Poiesz, western vice president of Norwalk, Connecticut-based Van Dyk Recycling Solutions (Van Dyk), which supplied equipment for the MRF. “With the high tipping fees in Santa Barbara, there’s of course a lot of avoided disposal costs when you do a high rate of recycling. At the same time, the state was mandating increased diversion of organics, so it was perfect timing [to build this facility].”

At the MRF, size reducers for liberating bags, 3D trommels, anti-wrapping screens, air density separators, elliptical separators and 11 optical sorters to identify recyclables by composition are used to recover and separate paper and containers from the MSW.

The recyclables captured at the MRF are then baled by a high-capacity baler from Bollegraaf Recycling Solutions and sold, while the organics move to the second phase of the project, the anaerobic digestion facility.

“The plant runs in two shifts; one shift runs clean recyclables and there are no organics. … But when they run the mixed solid waste or commercial waste, they try to maximize recovery of organics,” says Poiesz. “I would say 90 percent of the organics are going directly to the digester and about 10 percent is separated out. The material that is separated will either go to the digester or will be ground up and mixed in with the compost.”

Once recovered, the organic waste is transferred to the digester on-site, where it is dumped into heated tunnels and sealed airtight. It is then pumped with a mixture of 97 percent water and 3 percent cattle manure to start the digestion process.

The natural bacteria in the manure breaks down the organic waste to produce methane gas. The methane gas is then harnessed to create renewable electricity that is sold back to SoCal Edison (Southern California’s primary electricity supply company). According to the county, the electricity produced is enough to power the ReSource Center itself, as well as about 1,000-1,200 homes.

The leftover material in the AD tunnels is then sent to the site’s composter, where the last bit of glass or film plastic is removed, and the remaining compost is dried out. The compost machinery includes a densimetric table supplied by Van Dyk with manufacturer Allgaier Process Technology.

PROVIDING A MODEL

Between the multiple cities and communities that the Tajiguas Landfill serves, the Santa Barbara County Public Works Department estimates that roughly 200,000 tons of material are accepted each year. Of this incoming MSW material, the county says roughly 60 percent is either recyclable or compostable.

With construction of the ReSource Center, which was completed in July, the facility brings in 600-700 tons of waste per day and around 150-180 tons of recyclables, with 150,000-180,000 tons of trash and recyclables anticipated to be processed annually.

As for organics recovery, Johnston says he expects to collect about 40,000-50,000 tons out of the MSW stream, with 5,000 tons of that coming from the county’s source-separated organics program.

“As much as we make an effort to [separately] collect organics from food scraps and high organics-generating companies like restaurants, it’s not as effective [for getting volume] as going into the trash can [to recover leftover organics that haven’t been separated],” says Johnston. “There’s a lot of reasons for that. One, is that residents have this misunderstanding when we talk about organics … that we’re [only] talking about food waste, and food waste is only a small portion of that stream.

“These programs have always been hindered by low participation and not getting all the organics out. I think it’s because people dump their food scraps and think, ‘Cool, I’m done.’ But they forget about the other materials we want in the anaerobic digester like Kleenex, used paper towels, pet feces and green waste.”

This model of separating MSW into different streams to be processed individually is one of the reasons why Poiesz believes the ReSource Center will be so effective.

“That’s where this project is extremely unique because it takes municipal solid waste, it takes commercial waste, it takes recyclables and green waste, and all of that goes to one location and is processed; so, there are no escapes,” he says. “The [ReSource Center] allows a utility, or public-private partnership, to showcase that it is possible to build a facility like this.”

The author is the assistant editor of Waste Today and can be reached at hrischar@gie.net.