by Ashley Smith, 2024 Summer Programs Intern
When recycling household waste, many Texans are able to place intermingled piles of cardboard, plastic, paper, and other recyclable products into one bin. Whether disposing of these assorted materials in curbside recycling cans or at some drop-off centers, Texans are participating in single-stream recycling.
In communities with single-stream recycling, all recyclable materials are able to be placed in the same container. However, these items must undergo a series of sorting steps before being sold to end markets.
Material Recovery Facilities in Texas
Material Recovery Facilities, commonly referred to as MRFs (pronounced “murphs”), are central to this sorting process. After single-stream recycling is gathered by collection trucks, materials are brought to one of the many MRFs in Texas. There are currently 21 MRFs processing residential single-stream recycling in Texas.
These MRFs are found in the following Texas cities: Arlington, Austin, Corpus Christi, Creedmor, Dallas, Denton, El Paso, Fort Worth, Houston, Kilgore*, Laredo, McAllen, McKinney, Plano, San Antonio, and Taylor.
*The Material Recovery Facility in Kilgore, Texas has temporarily halted its operations due to a facility fire in June of 2024. It is scheduled to reopen Summer 2025.
What Happens at Material Recovery Facilities
When a collection truck arrives at a MRF, the full truck is typically weighed to determine the amount of material collected on its route. Afterwards, the truck’s content is dumped onto the tipping floor where all of the materials sit in a large pile waiting to be processed.
The next steps differ somewhat at each MRF depending on how much technology is utilized at the location. At some MRFs, human labor is almost entirely responsible for the sorting process while other MRFs rely on a combination of manual labor and technology to separate recyclable materials.
With recent technological advances, such as artificial intelligence, some MRFs have begun implementing highly automated systems. There are a variety of factors that determine technology usage at MRFs, including the age of the facility, the financial resources available, and the types of recyclable materials being processed.
While each MRF has its own operation process, the following is a common series of steps for sorting recyclables:
First, materials are pushed from the tipping floor to a conveyer belt.
Next, workers remove contaminants that do not belong in the single-stream recycling.
After that, lighter two-dimensional materials, such as paper products, are separated from heavier three-dimensional material. Disc screens, which allow two-dimensional products to fall through the holes in the screen, are commonly used to separate these materials. Additionally, an air stream can be used to blow lighter materials up to a higher level while the heavier materials fall to the bottom level.
Paper
After paper products are separated from the other materials, workers place cardboard, newspaper, office paper, and other light two-dimensional materials into their own distinct piles.
Metals
With the heavier three-dimensional materials still on the conveyor belt, a large magnet is utilized to pull out steel and other magnetic metals from the remaining materials.
Magnets are then used to create an eddy current, which is a special type of electrical current that is used to repel aluminum and other non-ferrous metals off the conveyor belt.
Glass
At MRFs that accept glass products, glass is separated from the remaining plastic materials. At some of these MRFs, workers manually remove glass from the conveyor belt while other MRFs utilize air streams to propel the lighter plastic materials up to a higher level. A glass crusher is used to pulverize the glass into small pieces called cullets.
Plastic
The plastic products on the conveyor belt are separated into distinct piles based on the type of plastic resin. There are seven main plastic resin types and the number inside the chasing arrows recycling symbol on products is an indicator of the kind of plastic the product contains. Workers are able to manually separate plastics by resin type. Optical sorters, which utilize image processing software to identify materials based on their physical and chemical characteristics, are also used to sort plastics.
Once all of the products on the conveyor belt are separated, the piles of individual material types are pressed into large rectangular bales using compactors.
At this point, all of the recycled materials are finally ready to be sold to end markets, which are the businesses and individuals who utilize the products once again.
The Importance of Single-Stream Recycling
By increasing access to single-stream recycling, Texas is working towards improving the state’s recycling rates. While the risk of contamination is higher in single-stream recycling than dual stream-recycling, single-stream recycling is more efficient for residents and collection companies. When people do not have to sort their recyclable materials themselves, recycling is far more convenient, and collection companies are able to reduce their costs by picking up fewer bins on each route. Additionally, the MRFs processing single-stream recycling provide economic benefits through increased job opportunities for local residents.
If your community has access to single-stream recycling and you want to see first-hand what happens to the materials disposed of in your curbside bins or at drop-off sites, many MRFs offer public tours of their facilities to educate residents on local recycling practices.
Learn More
If you are interested in learning more about what happens to recycled materials in communities that do not have access to single-stream recycling, check out our Keep Texas Recycling program, which works to expand recycling access in rural parts of the state.
By gaining a better understanding of what happens to recycled materials, Texans can help combat recycling misinformation and encourage those around them to maximize their use of local recycling systems.
