A Materials Recovery Facility, or MRF (pronounced “murf”), is an important part of both residential and commercial recycling programs. MRFs are facilities that separate and prepare materials for recycling. These facilities receive mixed materials and then sort those materials by type so that they can be shipped to recyclers and other phases of the recycling process.
What are the Different Types of MRFs?
There are two main classes of MRFs: clean MRFs and dirty MRFs. A clean MRF receives materials from your blue recycling bin. This means they only receive materials that are recyclable and that have been separated out from your household’s or business’s regular trash.
In contrast, a dirty MRF receives all of your trash without prior separation. Dirty MRFs can also receive regular trash that has already been separated so that they can go through it to find recyclable materials that were missed or accidentally thrown in the wrong bin. This allows for a higher rate of recovery of recyclable materials, but many of those materials are often contaminated by garbage and cannot be recycled.
There is a third type of MRF called a wet MRF. This is a type of dirty MRF that uses water to separate and clean the waste. Sometimes this water is also used to initiate biodegradation of some organic materials, readying them for anaerobic digestion facilities in the next phase of their recycling process.
What Do MRFs Sort?
MRFs recover a large assortment of recyclable materials. They sort out everything from paper and plastics to metal recycling materials. Aluminum, PET, HDPE, glass containers, cardboard, cartons, and small pieces of scrap metal are but a few of the materials that MRFs will separate for recycling. There are some nonrecyclable materials that are difficult for these facilities to sort and that can actually cause problems during the sorting process. Plastic bags and straws are not easy to recycle and create a huge challenge for MRFs. The flexible plastic gets caught in the equipment and can be difficult to remove. When you are sending waste to a MRF, keep these materials out to avoid clogging up the facility’s equipment.
How Do MRFs Work?
Different MRFs have different technologies and equipment that they use, but most of these facilities follow a similar process. Waste management services and individuals can both bring trash to a MRF. Vehicles drive over scales so that the facility can keep an account of the amount of waste that comes in and goes out. Each truck dumps its load of trash material onto the tipping floor then leaves. A large piece of material handling equipment such as a front end loader then transfers the material into the drum feeder. The drum feeder is a large steel bin that feeds the material onto the conveyor system at a constant rate. The drum inside the bin also monitors and regulates the density of the material so that the conveyor does not get bogged down.
The material travels along the conveyor to a pre-sort station. Here, workers stand alongside the conveyor to manually sort out trash, plastic bags, and other materials that are not recyclable and that can damage the equipment, setting them aside for proper disposal. Large pieces of scrap metal or plastic, such as pipes, are also removed from the conveyor so that they do not harm the sorting equipment or the workers.
After pre-sorting, the next step is removing large pieces of cardboard from the material conglomerate. Large sorting disks turn on axles to push this lighter material to the surface while all the heavier material remains at the bottom. Smaller versions of these disks can remove small pieces of paper from the top of the pile. When separated, these materials are moved to different conveyors so that they can be processed.
As the conveyor continues, ferrous scrap metals are then separated using strong magnets. All magnetic metal recycling is sorted out, which includes anything made out of iron or steel. Then, all non-ferrous metal recycling is separated using an eddy current separator. All of the non-conductive material left over will continue on down the line.
The next step is separating glass and plastics, and this is done using a density blower. The less dense materials, which in this case are plastics, are blown away from the denser glass material. The glass continues on a conveyor where it is then hammered down into cullet, a term for crushed glass. There are two methods for sorting the plastics that were removed. Workers can sort the plastics by hand, or optical sorters can be used to identify different colors and types of plastic. Special plastics like PET and HDPE can be separated using air classification, which separates material based on shape, size, and density in a column of air. Less dense and smaller plastics are lifted while denser plastics remain at the bottom.
Once all of the different types of materials have been sorted, they are each processed separately. Most of these materials are baled into large, dense masses that can weigh from 1000 to 1500 pounds. Glass cullet cannot be baled and is instead shipped as is to a glass recycling facility. The bales of plastics are shipped to plastic manufactures where they can be recycled into new products. Scrap metal recycling materials can be either baled or shredded before being shipped to metal recyclers or manufacturers who will then repurpose them or melt them down to be turned into something new.
Recycle Your Scrap Metal at a Scrap Yard in East Tennessee
MRFs are great additions to the recycling process and are helpful for making sure all recyclable materials are properly processed. While MRFs can recycle your ferrous and non-ferrous containers and other scrap metal, it is more beneficial to you if you recycle your scrap metal at a scrap yard. When you give your recyclable materials to a MRF, you do so for free or even sometimes have to pay a tip fee for dumping your materials. In contrast, if you bring your scrap metal to a scrap yard, they will pay you money to take it off your hands. Selling your scrap metal to a scrap yard is the perfect way to make some extra money and get rid of unwanted waste.
Here at Roane Metals Group, we make it easy to turn your scrap metal into cash. We’ll buy everything from steel to e-scrap. If you have some scrap metal that you are ready to get rid of, come by one of our two conveniently located scrap yards in East Tennessee. To find out more about recycling your scrap, give us a call at 865-354-4282 today.