Glass: Glass is 100% recyclable and can be endlessly reprocessed with no loss of quality. Once the customer has disposed the glass, it is taken to a treatment plant. It is then sorted (on the basis of type, color etc.), crushed, melted, molded and dried into a new product. Once sorted the glass in crushed into small particles called “cullet”. These are then melted in gas fired furnace to produce molten glass, which is poured into molds. In order to toughen the glass, it needs to be tempered. Tempering is a heat treatment process in which the glass travels through a gas fired tempering ovens. Tempering ovens heat the glass to about 600 – 630°C. Tempered glass is mainly used in automobile windows, computer, TV, and mobile phone screens.
 

Plastic:  Did you know that polyester fabric is made via recycled plastic bottles? Plastic bottles are sorted, shredded, cleaned twice in hot baths containing of caustic soda and thrown into gas fried rotating drums for approximately 10 hours for drying. The dried pieces of plastic are then heated in gas fired rotating screw to 270° C. The liquid plastic is force threw a sieve and emerges as great long strings (thread) which are collected in containers. These strings are not strong enough to make cloth yet. They are combined and stretched several times while being heated using gas, to bond the fibers together. These fibers are then torn apart again to create the raw substance needed to make polyester.
 

Aluminium: Recycling scrap aluminium requires only 5% of the energy used to make new aluminium from the raw ore. Used beverage containers make up the largest component of aluminium scrap. Aluminium is made up to several alloys, thus it is difficult to sort. Hence the sorting process of is a lengthy one. Once sorted the aluminium scrap is sent to propane fired furnaces where it is melted at a temperature of around 730°C. However, when aluminium melts it reacts with air forming a layer of aluminium oxide which floats of top. This unwanted oxide is scrapped off and the aluminium is ready for casting. The molten aluminium is then poured into molds to make cans, window frames, batteries, car rims etc.
 

Copper: Copper cables and wires are widely used especially in the electronic industry. Scrap materials are segregated (e.g. copper wires are separated from polyvinyl chloride coating). The copper collected is sent into gas fired furnaces for melting. Molten copper is poured into molds to make sheets or blocks of copper. These are then transported to various factories for manufacturing electronics, plumbing equipment, cookware / cutlery etc. These factories too use gas is used to re – melt and anneal the metal into various products (copper tubes must be annealed after bending).
 

Steel: From food cans, household containers, automobiles, and office buildings, steel makes up the largest category of metals in the municipal solid waste (MSW) and industrial waste. Steel since ages has been a recycled material throughout the world. The first step in the steel recycling process is the collection of scrap metal. While steel is wholly recyclable, some steel items might contain non – recyclable content or parts that might lower the quality of the finished product. Thus, the collected scrap is separated using specialized magnetic equipment. After identifying the recyclable steel items, the metal is shredded and heated in gas fired furnace. The molten metal is refined to eliminate dirt, debris, particles, and other impurities that may be present. Post refining, the pure melted steel is ready for cooling and solidification. Recycling plants use advanced systems to transfer hot molten metal from the heating and purification chambers to the cooling containers.
 

Rubber: Rubber is being used all around the globe in many things, most importantly, the tires of vehicles. It is necessary to recycle rubber as it increases landfill pollution. Rubber takes a long time to decompose and when it is burnt, poisonous and carcinogenic gases are released increasing the pollution. Tires no longer in use are collected and taken into a factory where there are tested for whether or not they are suitable for a new life. The tires which cannot be re – cycled into a new one are burnt in a thermal processing plant that burns the tires in an enclosed gas fired furnace. This converts the tires into usable energy without emitting harmful gases. The tires which can be recycled are repaired, vacuumed sealed and put in a gas fired autoclave where they are subjected to immense heat and pressure at 250°C for approximately 3 hours. Once cooled, finishing touches are applied and the tire is back in the market for sale.