Behind the Blue Bin

Nationwide, thousands of municipal curbside collection programs provide a weekly reminder on the importance of recycling in your community. But what happens when your recycling is picked up?

Although programs vary by city and/or county in materials collected, bin size and collection day, all recyclables generally go to a recycling center. This is the first step in the recycling collection process that leads to transforming them into new products. That’s when the real fun begins.

Earth 911 recently visited the North Gateway Transfer Station and Materials Recovery Facility (MRF) in Phoenix, Arizona to get a closer look at the curbside recycling process. The Materials Recovery Facility or MRF (pronounced MERF) handles an average of 4,500 tons of material in a given month. So even a short visit provides a lot of action.

Truckin’ It In

The MRF brings in between 110 and 140 truckloads of material each day, so the payload must quickly be sorted and processed to allow space on the floor for the incoming stream of trucks and materials.

Because the city collects on four different days each week, floor space is of utmost importance. No material will end up staying on the floor more than 24 hours, and an assembly line process ensures that materials are constantly moving.

Because Phoenix runs a single-stream (or commingled) recycling system, there is no separation of materials before they arrive at the MRF. To keep the program simple, all materials go in one recycling bin. Paper is mixed with aluminum, glass is mingled with plastic, and all this confusion is sorted out on the conveyor belts.

Recycling of Sorts

The first step in recycling at the MRF is to remove anything that is not recyclable. In Phoenix, the contamination rate (this is the amount of included material that isn’t recyclable) is between 20 and 30 percent, so this is a sizable task.

Contamination includes anything from plastics #3-#7 to scrap metal to mattresses, and occasionally the unorthodox product. North Gateway Transfer Station Administrator Terry Gellenbeck says one of his wildest memories was when an engine block was mixed in with recyclables, as it actually tore a hole in the conveyor belt.

Almost 75 percent of the material recycled at the MRF is paper, even though station officials estimate that as much as 30 percent of the paper eligible to recycle is thrown in the trash bin instead of recycled by residents. It is convenient to separate paper next because it is lightweight, and can be removed by using gravity.

North Gateway uses star screens to filter out the paper from other containers like aluminum and steel cans. This will separate office paper, newsprint and even junk mail. Employees manually remove cardboard, though.

At this point, other employees will sort out the remaining materials, comprised of aluminum, steel, glass containers and plastic bottles #1 and #2. These materials are baled in cubes and shipped off to a buyer interested in these valuable materials. The money earned from these sales helps offset the cost of operating the program and providing it to Phoenix residents.

Special Programs

Almost 90 percent of Phoenix homes have curbside recycling. Even though the North Gateway Transfer Station is constantly busy handling these materials, city staffers find time to provide other special programs and projects.

One special program is household hazardous waste (HHW) collection. The City of Phoenix does not have a permanent HHW facility, so North Gateway hosts several events each year to dispose of HHW. The city puts on 11 total per year.

Phoenix also just released a new slogan and campaign to encourage people to recycle, Recycling Changes Everything. Gellenback says that in addition to improving participation, the city wants to promote correct recycling practices as almost $1 million per year is spent sorting out and disposing of non-recyclable materials.

And the city of Phoenix continues to innovate. Just last week, the city kicked off its campaign to promote plastic bag recycling in partnership with local grocery stores and the Arizona Food Marketing Alliance. These bags can’t be recycled in the city’s curbside bin program, so Phoenix developed this partnership so the commercial locations that are originally supplying these bags can also assist in recycling them.

The North Gateway Transfer Station is also concerned about energy use. The city has installed solar panels on buildings and in the parking lot to reduce electricity consumption. The facility doesn’t encourage night visits, but it’s nice to know that the parking lot will be properly (and environmentally-friendly) lighted at all times.

All photos were taken by Sheila Bocchine.