Hollywood brings the environmental impact of people on the Earth to the big screen, but communities around the globe have been using recycling plants and centers to help deal with environmental issues. A recycling plant consists of a facility designed to process those materials that can be clean, treated and recycled into new products. Some recycling plants are located next to landfills to help make waste management a complete process. There are also a large number that are standalone and only deal with certain products.
Recycling can be a complicated and expensive process. Dealing with the sorting of materials causes many recycling plants the largest issues. Materials are sorted by type. Some can be removed with large magnets, but many of the materials have to be sorted by hand. Broken glass and plastics can make sorting tedious at best and dangerous at worst.
How Materials are Recycled
Paper products are shredded and mixed with water and chemicals to create a pulp. In many recycling centers this pulp will also undergo heating because heating the mixture can help to breakdown the plant material (or cellulose) that makes the paper. The pulp material is pushed through a screen to remove any contaminants that may have followed the paper through the recycling process - plastic or glue are two typical culprits. Additional cleaning process may also be used, including one that is used to remove ink from the paper products. This pulp can be pressed into new forms as is or may be mixed with new wood fibers to give extra strength or to make the resulting products smoother.
Glass products also begin with a separation. Colored glass can only be recycled into products that are the same color. The coloring of glass involves the addition of a coloring agent that cannot be removed even through the recycling process. Sorted glass moves on to be crushed. The crushed material then goes through a furnace to be melted down. The high heat causes labels to be burned off. The heat used to recycle glass is lower than the heat needed to create glass from sand. The resulting product shows significant savings in energy and costs.
Plastic products have been recycled to be used in a number of different products often different from their original use. Plastic has to be divided into types because not all plastics will mix together during the recycling process. After plastic goes through sorting it is ground into smaller pieces to make the melting process easier. The chipping process often leaves small pieces of labels and glue mixed in with the plastic pieces. These small pieces of plastic undergo a cleaning process to remove the contaminants. Melting down the plastic and then forming it into small pellets to be used in future products.
Aluminum products are the most common recycled. People collect aluminum cans and other products that can be traded into a recycling center for cash. Recycling plants do very little with the aluminum products. The cans are crushed into dense bales or bricks before being shipped to aluminum companies for processing.
The idea of sorting garbage or having multiple garbage cans is just two of the parts of the recycling process that can keep the public from participating. The good news is that scientists and engineers are working hard to create more single-stream recycling plants that will take the sorting out of the hands of the people. These plants have a number of systems (including magnets, air blowers and optical scanners) that help separate different products into the right area. As recycling becomes the standard way of dealing with many different forms of waste then the process for recycling will continue to improve.
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I’ve got to admit that I wasn’t aware about the wetting and screening process that waste paper undergoes. Until now, we’ve simply shredded paper, but a pulping and screning process would significantly improve the destruction of confidential information on paper.