Living up to expectations

Features - MRF Operations

Cal-Waste underwent a total system upgrade at its MRF in Galt, California, that has helped to increase throughput and the quality of its final products.

December 8, 2020

Photos courtesy of California Waste Recovery Systems
Cal-Waste added various screens supplied by CP Group, including a primary auger screen and five MSS optical sorters when it updated its MRF in Galt, California.

For more than eight decades, California Waste Recovery Systems (Cal-Waste) has been serving residential, commercial and industrial customers in the California cities of Lodi, Galt, Stockton, Elk Grove, Sacramento and Angels Camp, as well as in Alpine, Calaveras, San Joaquin and Sacramento counties.

As one of the largest waste collection and material recovery operations in its region, Cal-Waste offers recycling services, green waste collection and trash services.

To help meet a state requirement to recycle 75 percent of all commercial waste generated in California, Cal-Waste opened an $11 million material recovery facility (MRF) at its headquarters in Galt in 2013 featuring equipment supplied by San Diego-based CP Group.

In late 2019, after recognizing the need to reduce contamination and in light of the declining global market value for some recyclables, Cal-Waste invested roughly $20 million to upgrade its MRF, again selecting CP Group as its equipment provider. The upgrade was designed to increase the facility’s throughput in addition to improving the purity of recovered recyclables.

“We built the MRF in 2012 and learned a lot about the new recycling markets and what the demands were, [and] it was really very lax,” Dave Vaccarezza, owner of Cal-Waste, says. “But then we watched the standards tighten back up to where anything above 1 percent is considered contamination,” he continues.

“Knowing that, we’ve always worked on quality and knew that if we’re going to stay in the game and we’re going to deal with China’s Sword and these new standards, we have to be able to produce a superior product to stay in the market,” Vaccarezza adds.

“When it came time to make the switch, we went right to CP and said, ‘OK, we want to go to the next generation,’ and that’s what they brought us,” he says.

A modern fit

Cal-Waste’s recent total system upgrade included the addition of a primary auger screen, a glass breaker screen, an AWScreen, a CPScreen, a scalping auger screen and five MSS optical sorters.

Housed in a 100,000-square-foot tilt-up concrete building, the MRF’s operations encompass receiving, screening, sorting, baling, marketing and shipping of recyclables generated by residential and commercial customers.

Operating in two shifts, Cal-Waste deploys its recently added optical sorters on its mixed paper and plastics lines to remove contamination.

“We have optical sorters that handle the mixed paper element, so we’re able to get more out of mixed paper and [can] take chipboard out of that stream in some cases,” Vaccarezza says. “Another major thing that our optics [sort] is plastics, and those optics are able to identify all seven plastic types.”

He adds that the company is producing natural high-density polyethylene (HDPE), colored HDPE, clear polyethylene terephthalate (PET) and colored PET.

Vaccarezza says adding the optical sorters has “opened [us up to] specific markets, like in the chipboard market, and the plastic markets, [because] we’re able to get it down to exactly what they want.”

One of the many components of the recent upgrade, Vaccarezza says the primary auger screen “takes the burden depth down to a much more manageable level and does a great job of spreading everything out so there are no big lumps and clumps.”

It also has allowed Cal-Waste to reduce the number of sorters on the presort line from eight to four. Even with the reduction in workforce, the MRF has increased its capacity from 11 tons per hour (tph) to 30 tph.

Previously, the MRF was capable of processing 150 tons of recyclables per day, totaling more than 54,000 tons per year. With the upgrade, Cal-Waste is currently processing about 65,000 tons per year, which is somewhere around 300 to 400 tons per day, Vaccarezza says.

“We’ve done more than 30 tons an hour, and we’re still fine-tuning it in terms of the product that is coming out on the back side,” Vaccarezza says. “CP is working with us very closely to get the system all tuned up.”

The road ahead

Since Cal-Waste began operating the updated system, Vaccarezza says downtime has dropped significantly.

“In our old plant, I’d say we’d have two hours of downtime every nine-hour shift. Now, we’re down to maybe less than an hour, so we’re getting a good six-and-a-half to seven-hour runtime on it every eight- to nine-hour shift,” he says.

Vaccarezza credits this to the new equipment and to the software that comes with it. With more efficient rotating screens and a new supervisory control and data acquisition (SCADA) system, he says the retrofit has been a major time-saver.

“The [new] system has what’s called SCADA, which is basically a dashboard that tells you how fast your plant is running live. In the past, you assessed the plant based on how fast the motors were running; you really didn’t have a concept of weight, and there were no scales to really be able to measure your production live. Whereas, now we have a volumetric scanner that tells you accurately how much volume is going through the machine.”

Cal-Waste has been running the upgraded system since January, and while Vaccarezza says the company is still fine-tuning it, he thinks the system is living up to its performance expectations.

He adds that Cal-Waste views this new equipment as a foundation that the facility can build on over the next five to seven years, and the company plans to begin extracting material from the residual line to create engineered fuels or animal bedding products.

Although the updated MRF has been highly efficient, Vaccarezza says contamination in incoming material is still a reality that Cal-Waste must deal with. According to the company, contamination levels can vary by community and by program and range from 18 to 42 percent.

Vaccarezza says ongoing community outreach and education are critical to reducing contamination.

“I think that the key to all of this is really public education,” he says. “One of the things that we recently have been able to present to the Sacramento/San Joaquin markets is a unified message so that all customers understand what’s recyclable and what isn’t recyclable.”

Each of Cal-Waste’s residential carts now includes information on what can be put in the recycling bin. “If we can get the consistency on our outreach, I think that that’s really the key to making our machinery work even better,” Vaccarezza says.

This originally appeared in the Nov. issue of Recycling Today. The author is assistant editor of Waste Today. She can be contacted via email at