12 December, 2012
Everyday people see building being put up everywhere. One might ask themselves where they get the room to construct these huge structures. Most of the time old buildings are getting demolished and new building are being built in the place of them. The one thing people usually do not think about is where does the demolish building go after it had been removed from the job site. The part that this report is going to go into detail with is what happens to the steel after it has been removed from the job site. Furthermore it will explain the process of recycling various steel materials such as automotive, steel cans, old structures, and many others. This report I ultimately will find out if it will be more beneficial to recycle steel or to purchase new steel after being newly produced.
Recycling may seem like a modern concept starting with the environmental movement during the 1970s, it's actually been around for thousands of years. Before to the industrial age, you couldn't make goods quickly and cheaply, so almost everyone practiced recycling in some form. However, large-scale recycling programs were very rare households predominantly practiced recycling. The mass manufacture of the industrial age is, in many ways, the very reason we need to worry about large-scale recycling. When products can be produced and purchased very cheaply, it often makes more economic sense to simply throw away old items and purchase brand new ones. However, this nation of disposable goods created a number of environmental problems, which we'll discuss in detail in the next section.
In the 1930s and 40s, maintenance and recycling became important in American society and in many other parts of the world. Economic depressions made recycling a necessity for many people to survive, as they couldn't afford new goods. In the 1940s, goods such as nylon, rubber and many metals were rationed and recycled to help support the war effort. However, the economic flourishing of the postwar years caused conservationism to fade from the American consciousness. It wasn't until the environmental movement of the 1960s and 70s, heralded by the first Earth Day in 1970, that recycling once again became a mainstream idea. Though recycling suffered some lean years due to public acceptance and the market for recycled goods not growing it has generally increased from year to year The success of recycling traces to wide public acceptance, the improved economics of recycling and laws requiring recycling collections or enforcing recycled content in certain manufacturing processes.
The first step in the recycling process starts with the debris from the demolished building is taken to a material recovery facility. There some facilities have their own method on how to extract the steel from the rest of the debris. The general way how the metal is separated from the debris is first all the metal is dumped into one pile. From there a crane with a magnet or an excavator will grab the material and place it onto a conveyor belt. Once one the conveyor belt the material will run through a double feed roller where the metal is crushed by a hammer until the pieces are small enough to fit through a grate below the machine. After passing though the grates a magnetic steel drum will pass over the material and spate the metallic pieces from the pile and the rest of the material will be sucked up by a vacuum and place into a bin where later it will be disposed. Once the steel is separated it is shipped to a steel mill where it will be put into a blast furnace and melted down at a very high temperature to remove any impurities that might still be inside the steel. Once the metal has been melted down and free of any other impurities it is poured into a mold which will form the new steel member. The following picture is a blast furnace melting down the