A refinery is a factory or processing plant where crude or elementary materials are processed into more usable forms. There are many different types of refineries that can create all sorts of products, from petroleum to table salt. Refineries often contain complex mechanical systems that allow the safe and correct transmutation from raw materials into finished products.
Probably the best known type of refinery is an oil refinery, where crude oil is exposed to chemical and mechanical processes to turn it into more usable forms. Gasoline, kerosene, and petroleum products can all be created at an oil refinery. These refineries have incredible economic and strategic importance to many regions; in war, oil refineries are often the first targets as they can slow or halt the infrastructure of the other side. Since so much of the world's technology currently runs on fossil fuels processed by refineries, the safety and effectiveness of these processing plants is of major concern throughout the world.
Many of the oldest refining techniques in the world are used to process raw food into finished products. Sugar refineries have existed for centuries, turning beets and cane into the many forms of sugar used in everyday cuisine. At a modern sugar refinery, the raw materials are purified, saturated, and finally dried into the correct concentration to be shipped out for packaging.
One important consideration when examining refineries is the production of byproducts. These are separate compounds created during the refining process that may have their own uses. For instance, molasses is a byproduct of sugar refineries. Sulfur and sulfuric acid are sometimes byproducts of petroleum refining.
Safety is a major concern at nearly all refinery operations. Oil and gas refineries have an enormous fire and explosive danger, as the materials are combustible by nature. Additionally, workers are often in danger of exposure to pollutant and corrosive chemicals and fumes that can result in chronic or even fatal injuries. Unfortunately, refineries have a long history of accidents and deaths due to oversight and even intentional cutbacks on safety measures. Many government agencies and labor unions consider tough refinery safety standards to be a major priority in the industry.
Pollution is another major concern in the operation of refineries. The chemical processes as well as the high amount of energy needed to run a large refinery can all contribute to greenhouse gas emissions and increased air, water, and soil pollution. With global warming becoming a major concern in the 21st century, activists and some environmentally-conscious refineries are seeking ways to reduce pollution and incorporate green technology, such as alternative energy, into refinery use.