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Glass Recycling – The Rocky Mountain Bottle Company Wants Your Glass

By Julie Smith, Golden, Colorado

Located just a couple miles north of Golden, in Wheatridge, the Rocky Mountain Bottle Company (RMBC) recycles massive amounts of glass. To learn more about the glass recycling process and how it fits into traditional manufacturing processes, I visited the RMBC, and met with two Batch and Furnace Manufacturing Specialists, Ryan Schneider and Keith Cembalisty. They generously shared their extensive knowledge of glass manufacturing and recycling, with a passion that is nothing less than contagious. Glass is made by melting raw materials, mainly sand, soda ash and limestone, in huge furnaces that are heated with natural gas. The blend of raw materials used to make the glass melts at around 2800 ºF, while cullet, or ground-up recycled glass, melts at a much lower temperature, around 1500 ºF, so the addition of cullet to the blend helps to reduce the melting temperature, saving natural gas.

Currently the RMBC includes about 30% cullet in the blend with raw materials. It turns out that glass is infinitely recyclable, and a lot of energy and raw materials are saved in glass-making when recycled glass is used instead of raw materials. The RMBC would be happy to use up to 70% cullet in their blend, if they could get it. Currently, only about 40% of the recycled glass that goes to RMBC is from local sources, and the rest is imported from other states, such as Oregon, Michigan and Wisconsin. Sadly, Colorado has one of the lowest recycling rates in the country, 15% at most, compared to the national average of 32%.

There are actually two glass plants in Colorado – The RMBC in Wheatridge, and the O-I Bottling Facility in Windsor. Both facilities need more recycled glass. RMBC currently averages about 750 tons/day of glass production, around 200 tons of which is recycled glass, with only 80 tons coming from Colorado. The Windsor plant makes 800 tons/day of bottles, and currently includes 16% cullet, 95% of which is local. For every ton of glass that is recycled, more than a ton of mined raw materials are saved, including 1,400 LBS of sand, 430 LBS of soda ash, and 400 LBS of limestone. How can more than a ton of resources be saved for a ton of glass? It’s because, in making the glass from raw materials, there is a fusion loss of about 15%. The raw materials (primarily soda ash, limestone, and sand) release additional emissions in a complex high-temperature chemical reaction during the glass melting process, according to Ryan. For every six tons of recycled container glass used, a ton of carbon dioxide, a greenhouse gas, is reduced. A relative 10% increase in cullet reduces particulates by 8%, nitrogen oxide by 4%, and sulfur oxides by 10%.

What if Colorado recycled ALL of our glass, so that RMBC could get the 70% cullet that is needed from within the state?

· We would increase recycled glass to RMBC by 267,180 tons per year.

· Recycling 1,000 tons of glass creates 8 jobs, so hundreds of local jobs would be created.

· Carbon footprint of electricity and natural gas at the glass plants would be decreased by 35,088 tons CO2 per year.

· Land for Mining – raw materials used to make glass are mined and then refined in industrial operations, typically in open pit mines that scar the land and make it unusable for wildlife, adding to the many stresses we are placing on wild species that are driving them to extinction.

· Landfill Space – currently glass makes up 4 – 5% of municipal solid waste. Like land for mining, landfills take up yet more precious land that our wildlife so desperately needs to survive and avoid extinction.

Given all these benefits, Colorado, with two of the biggest glass plants in the west, currently has the lowest recycling rate of any state in the country. By far. The current national recycling rate is about 32%, while here in Colorado it’s an embarrassing 15%, at best, less than half the national average. Currently, these plants only get around 50% of their cullet from Colorado. The rest comes from Oregon, Wisconsin and Minnesota. What a pathetic waste to send all that glass to landfill, while the local glass plants import more than 50,000 tons of recycled glass per year, adding nearly 9,000 tons/year of CO2 emissions in transportation. In Golden, most of the glass that is recycled comes from single stream bins at single-family residences, and through glass collection bins located in a few places in the area. Sadly, only a few bars, restaurants, commercial buildings and apartment buildings recycle any waste at all, including glass. This leaves it up to us consumers to figure out where to give our business. If we choose to be a part of the circular economy, something that is sorely needed to help our planet, it’s up to us to find out if a given venue recycles. Otherwise, if we are served a drink in a glass bottle, that bottle may likely go to landfill. Of course, we can always choose to take the bottle home with us and recycle it ourselves.

Why wouldn’t local businesses and residents want to take responsibility for the containers they buy and sell with every consumer choice they make? You’d think that recycling glass would be the ultimate low-hanging fruit to help reduce our planet’s runaway global warming. 115,000 tons per year of CO2 is a lot.

How to Recycle Glass

The best way to recycle glass is to place it in a glass bin. There are 6 glass bins in the area that are currently accessible to the public:

· Behind Bill Coors Wellness Center, 12th and Ford, Golden

· Rocky Mountain Bottle Company, 10619 W. 50th Ave, Wheatridge

· Lakewood Recycling Center, 1068 Quail St., Lakewood

· Arvada Elks Lodge 2278, 5700 Yukon St, Arvada

· Arvada Zero Waste Center, 6240 W. 54th Ave., Arvada

· Glass-to-Glass, 11331 Dillon Road, Broomfield

· Eco Cycle, 6400 Arapahoe Rd., Boulder

· City of Fort Collins and City of Loveland also have several glass bins.

If you don’t have access to a local glass bin, you should at least place the glass in a single stream bin. In the recent past, most of the glass in single-stream collection systems ended up as road-fill, or, worse, ultimately landfilled. Now, the separation technology is advanced enough to recover glass from single-stream efficiently and provide a decent quality of cullet. More processing is needed to recover glass from single stream, so it’s always better to put the glass in a dedicated bin, if possible.

A new company in Broomfield, Glass to Glass (, is providing a glass collection service in Colorado. They provide collection bins at no cost, and they pick up the glass when the bins are full. They take the glass to their facility, where they clean it, remove the lids, labels, and other contaminants, and grind the glass into cullet, which is then sold to the RMBC, where it is melted back into bottles. Often, the recycled glass is made into a new bottle in as little as 2 – 4 weeks. If you have a suitable location for a bin, you can contact Celene Peck-Andreano at Glass to Glass, (720) 580-0545,

Responsible Glass Recycling

Before recycling, glass containers should be lightly rinsed to remove build-up. Please don’t toss contaminants, such as porcelain, mirrors, windows, pyrex, glass cookware, spectacles, drinking glasses, vases or light bulbs into the glass bin, or into the single-stream recycling bin. This is important, because these are made of different materials than glass bottles and jars, or are treated to withstand extremely high temperatures, and should be recycled separately. For example, a small amount of porcelain can ruin an entire batch of glass, by creating unmelted “stones” in the glass. Also, previous attempts at placing unsupervised recycling bins in Golden have seen problems with trash and other inappropriate items in the bins, which makes cleaning and separation more difficult, and ultimately can result in removal of the bin.

We are lucky to have a nearby glass plant that provides the opportunity to keep single-use containers within a circular economy that minimizes the use of mined raw materials and reduces the carbon footprint of these containers. If we recycled enough glass bottles and jars in Colorado to supply our local glass plants with local cullet to help them reach their goal of 70% cullet, we would save more than 115,000 tons of CO2 emissions per year, which would go a long way towards reducing our carbon footprint and helping our planet. How’s that for a win-win? Together, we can make a difference on our planet by recycling glass responsibly.

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Glass Recycling – Equations and References

By Julie Smith, Golden, Colorado These equations and references support the Glass Recycling post. Equations 1. We would increase recycled glass to RMBC by 267,180 tons per year. RMBC – 750 tons/

1 commentaire

Thanks for this wonderful article. I kept finding really doable solutions to this problem and it is embarrassing that Colorado considers itself so environmentally aware, conscientious, and responsive but we are so poor at the simplest thing-recycling. It sounds like a great topic for an environmental film, to be shown at the Colorado Environmental Film Festival next year. Hopefully someone will take up this idea and make a film!

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