Waste glass recycling and the end-use markets for recycled glass sand and aggregates are an integral and exciting component of a community’s comprehensive waste management program.
By Cynthia Andela

In the evolving landscape of waste management, glass recycling has experienced a transformation over the past few years; sorting glass by color has often become economically unsustainable, and there are fewer glass bottle makers and other end users for sorted glass cullet.

Concurrently, communities, consumers, and municipalities have resorted to mixing all types of glass into a single recycling stream, and the compromised product has primarily been landfill cover, essentially wasting a valuable resource.

Public Outcry
Many private and public recycling operators have removed glass from recycling programs without community consensus, and valuable glass cullet has primarily been landfill cover. When citizens discover this, they renew their calls for drop-off or redemption centers. Community and municipal buy-in is required to provide and pay for such services. Another consideration is the development of local markets for mixed glass sand and aggregate.

There is also a significant amount of post-industrial and post-consumer glass to recycle, such as plate glass, laminated glass (like windshields), and household glassware, to name a few. The continued effort to reach zero waste in the commercial and manufacturing business sectors is increasing the call for glass recycling operations and markets.


Glass for recycling.



Glass mulch.


Sustainable Municipal Waste Practices: Afterthought to Crucial Component
As municipalities embrace environmentally conscious approaches, removing glass from recycling programs has become unacceptable. With growing community awareness of the environmental benefits of recycling, increasing regulatory support, and growing consumer demand for eco-friendly services and products, alternative options for mixed-glass recycling have witnessed a surge in interest.

Waste glass, consisting of unsorted glass bottles, broken or whole, plate glass, ceramics, and most frangible material, when processed by the right equipment becomes clean glass sand, with rounded edges. There are many markets for clean glass sand and aggregate, including:
• Soil additives, compost mixes, marshland restoration
• Construction sand or aggregates
• Filtration Sand
• Landscaping mulch, hiking, and horse trail augmentation
• Sandblasting medium

Crushing-pulverizing and screening equipment and systems have been designed specifically for waste glass cleaning and sorting, making entry into these markets feasible.

Essential Systems and Equipment: Powering Efficient Glass Recycling
The key to safe and clean glass sand and aggregate is to choose pulverizing technology with a heavy-duty and wear-resistant design, and an efficient screening-cleaning system that separates the glass from waste debris. The system must be well-suited for glass mixed with other non-glass materials. Look for flexible impactors that selectively crush the glass or other frangible materials and screen out the non-glass components.

For municipalities and private concerns considering the incorporation of a sustainable glass recycling system, understanding essential systems and equipment is paramount. Questions to be answered include how many tons per hour will process through the machine, and what are the end uses for the product. Strategically designed systems ensure a seamless flow of the recycling process, minimizing downtime, and enhancing productivity, ensuring a successful recycling facility.


Glass as a blast media.



Incorporating Glass Recycling: Factors to Deliberate
The decision to incorporate a waste glass recycling system into or at a facility is multifaceted, demanding careful consideration of several key factors. The first step involves assessing how to get the glass out of the waste stream, and into the recycling stream. Consumer waste glass, along with industrial waste glass, can all be diverted from the landfill and processed into beneficial sand. If waste glass constitutes a significant portion of the waste stream and its related landfill costs, then the viability of a recycling system becomes more apparent.

Regulatory support also plays a vital role, as governmental policies and incentives can drive the economic feasibility of such ventures. Economic factors, including the availability of end markets for recycled glass sand or aggregates, must be evaluated to ensure the sustainability of the endeavor. It is imperative to analyze the upfront capital investment required, operational costs, and potential return on investment.

Starting a Glass Recycling Business: Items to Consider
Whether you want to start a glass recycling operation, or simply help to provide a solution for glass recycling in your community, there are a number of items to consider:
• Technology: Components such as crushers, pulverizers, trommel screens, conveyors, and hoppers can be engineered to make turn-key systems tailored to operational parameters. The best machines create a finished product consisting of crushed cullet, or glass sand and aggregates with rounded edges.
• Funding: Can you get community support and funding to make this possible? Private donations? Grants? Loans? Investors? Look for leasing options. Incorporate into an existing or new recycling system.
• Sources of glass: How much, what kind, and how will it get to your recycling location? Consider a charge to provide service, or a “free at your recycling location” model.
• How much waste glass is available?: What recycling programs are in place now? Can separation and collection programs be set up for consumers, restaurants, businesses, etc.? Who would set these programs up and provide the service (at a fee) to place containers for the glass and bring them to the recycling center? Consumers are willing to pay for curbside or processing of glass if they can see what is being produced. If they can take home a bag of glass sand for their garden, they see the circular market and value produced.
• Types of glass that can be accepted: Bottles, plate glass, mixed-color glass (MRF Glass), and ceramics. Look for systems that will process all types of glass, with no sorting or pre-cleaning needed. Glass may contain non-glass residuals, labels, plastic, or metal tops and caps.
• Location: Where can you locate the machine? Are any permits needed? Is it available and convenient for people and businesses to bring you glass?
• System Size: Systems range from 1/2 to 20 tons per hour. The size of the machine depends on whether you will hand-feed with a barrel or a small box tipper. Larger systems need to include a surge hopper for loading with a bucket loader.
• Other Considerations: You will need a concrete pad and three-phase power. A bunker to drop off the glass, and a loader to pick up and put in the surge hopper. Most machines can be located outside, best practices suggest a rain/sunroof and windbreak. Well-engineered machines are not very noisy. The glass being deposited in the bunker or surge hopper is the loudest intermittent noise. Dust can be controlled with a misting system. The glass dust is not crystalline silica, it does not harm your health.


Andela glass recycling equipment.


Recycled glass sand coming out of trommel screen


Andela glass sand.
Imaegs courtesy of Andela Products.

Glass Recycling: A Circular Solution
Waste glass recycling and the end-use markets for recycled glass sand and aggregates are an integral and exciting component of a community’s comprehensive waste management program. Glass began as sand and waste glass turned back into cullet to make new bottles, or back into clean sand for a myriad of end uses, is truly circular. Clean glass sand that is not sharp and is in the correct size and gradations for end uses is something to which everyone relates and can find a use.  | WA

Cynthia Andela is President of Andela Products, a leading manufacturer for over 25 years of glass reduction equipment and systems to process all types of glass into a recycled glass sand and aggregate with no sharp edges, or into glass cullet for new bottles or fiberglass. In 2013, she started Ruby Lake Glass, LLC, a recycling company making color coated glass sand/aggregates. Cynthia can be reached at [email protected] or visit www.andelaproducts.com or www.rubylakeglass.com.