Bottles of beer from local breweries pack the cold cases of liquor stores across Denver. But what happens to the glass bottles after customers enjoy their liquid contents? The city of Denver is encouraging residents to put them in purple recycling bins at no cost—underscoring that suggestion by starting a new program to charge for solid waste—i.e. trash—destined for landfills.
Beer bottles, along with yogurt containers, cardboard, cans, and other recyclable items, go into one bin, called single stream, which is picked up by a large white truck and taken to a massive sorting facility in southeast Denver.
Once there, as Vanessa Lacayo, spokesperson the city’s Department of Transportation and Instructure explains, trucks are weighed and then empty their loads in barns that correspond with the contents including stalls for garbage, recycling, and compost.
The goal is to reduce the waste that’s diverted to landfills, according to Nina Waysdorf, the Waste Diversion and Recycling Manager for the city. She said that about 75 percent of the city’s residential waste stream could either be recycled or composted, but only about 25 percent is currently diverted. “A huge gap” that she says is calculated by audits they perform in which they pick apart the trash and measure what is not being recycled.
Lacayo adds that glass is highly recyclable and can be turned into new bottles and jars over and over again. According to the Glass Packaging Institute, glass is 100 percent recyclable and can be reused endlessly without loss in quality or purity. But across the nation, people recycle only about one-third of all glass they could. Chemical & Engineering News reports that some European countries recycle more than 90 percent of their glass.
The materials that Denverites put in their purple recycle bins, including beer bottles, are taken from one of barns at the city’s collection center by a trailer truck to a materials recovery facility, or MRF, in north Denver, about eight miles away. At the MRF, which is a Canadian company called GFL, the materials are sorted into different groups—glass, plastic, aluminum, and paper.
The journey of the glass bottle continues after being sorted from other recyclables at GFL. It then gets taken to a company called Glass to Glass, in Broomfield, Colorado, where all non-glass materials, like metals, labels and adhesives are removed. This facility is owned by O-I, a global manufacturer of bottles. Robert Hippert, the Sustainability Strategy Leader for the company, said that they receive MRF material streams from several different facilities in the greater Denver area. The glass is sorted by color—amber, green, and clear. Then Glass to Glass produces what’s called “cullet,” small pieces of recycled glass that can be heated and made into new bottles. Those cullet pellets could either go to a facility that serves Molson-Coors in Golden or to an O-I bottle manufacturing plant in Windsor, Colorado, about 50 miles north of Denver.
The Windsor plant is a massive and noisy place humming with activity. Walking through it requires safety glasses, steel-toe shoe covers, and ear plugs. The cullet from Denver is brought in by railcar at the east end of the facility, but Hippert says it’s not enough to meet the needs of the plant, so they have to use raw materials, soda ash, limestone, sand, and a little bit of alumina that are also brought in by train.
The materials are then conveyed inside the plant where two immense and very hot furnaces melt them into molten glass that flows into basins where it will eventually be molded into bottles. Bottles whirl through the plant on belts and ramps at a dizzying speed with incredible precision as computers track their progress, beginning as what looks like hot lava poured into molds to finished bottles that are cooled and then inspected. Freshly made bottles are then bundled up to go to Budweiser, Left Hand, and New Belgium, among other Colorado brewers, and they also ship bottles out of state. The plant runs around the clock, making about 3.5 million bottles a day.
Hippert said that using recycled material from old beer bottles saves energy, and a typical rule of thumb is that for every ten percent increase in cullet used in their batch formula, they can save about 2.5 percent energy. He also noted that by adding recycled content, they reduce the total amount of carbon dioxide emissions.
The energy savings could be much higher, and if it were up to Hippert, they would have a whole lot more cullet used at the Windsor facility. Their goal at O-I is to try to run on 50 percent recycled content in the bottles they produce. But given low recycling rates in Colorado, they have to import glass cullet from recycled bottles from other states as far away as Oregon, which has had a bottle bill for over 50 years that pays a fee to customers to return their bottles.
So why doesn’t Colorado recycle well? Liz Chapman is the Executive Director of Recycle Colorado, the largest nonprofit in the state dedicated to education about and lobbying for recycling. She said that more than half of the glass that is taken off the shelf and could be recycled is thrown into landfills in Colorado. Chapman says Coloradans only recycle about 16 percent in total of what could be recycled—about half the national average. Many bottles end up in landfills because some places in the state don’t have adequate recycling options.
Chapman is quick to add that the bulk of the glass that’s not being recycled is not coming from residences but from many bars and restaurants that don’t have the time, space, or finances to recycle. However, there are some bars and restaurants that take sustainability seriously and train their staff.
Chapman said that there are places in the state unlike Denver that do not have the infrastructure to recycle anything including beer bottles. That contrasts with the fact, she says, that the state has a glass remanufacturing facility with the potential to create jobs and supply it with the recycled glass it needs.
The recycling landscape is changing in the state after the legislature passed the Producer Responsibility Program for Statewide Recycling act last year. The bill imposes charges on firms that make bottles, cans, paper packaging, and food utensils to fund recycling around Colorado. The program is getting established by first performing a needs assessment and hopes are it will be fully implemented in about three years.
Additionally, in the November 2022 election, Denver voters approved a measure that requires restaurants, office buildings, and apartments to offer recycling. That could mean any beer bottle has a chance for an everlasting life.