If you recycle on a regular basis, then you understand the steps that you must take to get materials from your home to the recycling bin. But what happens to your glass, metals, and plastics once collectors take them away? Though you may never witness it, each material undergoes a unique process to ensure that it can once again re-enter the product stream as new items. Read on to take a closer look at five of the most common recyclables and what happens to them during the recycling process:
Upon arrival at the recycling facility, workers wash plastics to remove any labeling or other possible contaminants. Next, the facility sorts each type of plastic into a separate category. For example, all PET plastics—such as water bottles—go into a group of their own. After isolating each plastic type, the facility breaks each material down into smaller pieces. To this end, they load the plastics into shredding machines that tear them into flakes or chips.
Next, the facility heats the pieces until they melt and then reshapes them into small pellets or fibers. The final step involves sending these recycled plastics to manufacturers who use them to create brand-new products, such as furniture, insulation, and carpeting.
After consumers place their glass recyclables for collection or bring them to recycling plants themselves, workers begin the process of organizing these materials by color. Some facilities may, however, skip this step by requiring local consumers to pre-sort their glass into groups of clear, brown, and green containers.
Recycling workers then wash all separated glass pieces to rid them of debris and run them through special machinery that compresses them into a material called cullet. After combining this substance with limestone, sand, and soda ash, workers place the entire mixture into a furnace for melting. Recycling plants can use the resulting material to create new containers or other glass products. The durability of glass makes it possible to repeat the recycling process an infinite number of times.
All metals typically fall into one of two categories: ferrous (combinations of carbon and iron) and non-ferrous. The former group consists of materials such as iron, wrought iron, and steel. The latter contains aluminum, copper, and tin, as well as precious metals like silver and gold. Most recycling centers process non-ferrous metals, many of which originate in the homes of consumers. However, iron and steel top the list of the world’s most recycled materials. This is due to how easy it is to get these materials from demolished buildings and scrap yards. In fact, almost 40 percent of all crude steel production uses recycled steel products.
Once the metals arrive at the recycling facility, workers separate them by category using specialized magnets. After inspecting each item to determine its quality, they wash the metals using water or chemicals to rid them of their paint and any protective coatings. Facility workers then shred the metal items and feed the pieces into designated furnaces for melting. When these materials reach a liquid state, workers pour them into molds that will allow them to cool into an oblong-shaped block called an ingot. The recycling process ends when workers transform these ingots into large, malleable sheets of metal and send them to manufacturers for reuse.
When consumers place their paper recyclables into their curbside bins, collectors transport them to the local recycling facility, where workers sort them into different groups depending on their grade and type. The paper must then enter the “pulping” stage, during which time workers filter it through a mill. As it combines with water, the paper separates from any glue, ink, or other non-paper elements and transforms into a slurry-like material. Recycling workers then process this pulp several more times to fully prepare it for reuse. During this step, they can also add in various elements that will turn the pulp into different types of paper, like cardboard. They then use the paper slurry to create large sheets, which they let dry before rolling and shipping them off to their final destination.
In order to prevent old mobile phones, computers, and other electronics from ending up in landfills, recycling centers must send these items must undergo numerous recycling steps. This process begins when the facility sorts each electronic item and separates it from its battery components. Workers must then begin taking each electronic apart by hand, a step that involves retrieving the most important parts and classifying each one by type. In some cases, certain components, such as circuit boards and batteries, must go to special processing facilities.
After dismantling, facility workers must break down any item that people cannot easily re-use into pieces that are no larger than 2 inches. Recycling facilities require these e-waste pieces to go through another step of disassembly, which ensures the removal of all dust particles. After further separating of materials using magnets, water, or a combination of both, facilities then send the salvaged items off for reuse. Metal components such as tin and copper go to smelting facilities that safely recycle them.