The Process of Refining Iron
Iron is one of the most abundant metals on Earth. It has been used since ancient times as a material for weapons, tools, and building materials. Refining iron is a process that has been in use since the dawn of civilization. This process involves extracting impurities from the iron ore, in order to produce a pure and usable iron. The refinement process can vary, depending on the ores origin, and the tools and technologies used.
The process of refining iron can be dated back to 2000BC in Ancient China, when the production of iron was done through primitive methods. The Iron Age began in about 1200BC, when the technique of smelting iron ore with charcoal was discovered. Charcoal is composed mostly of carbon, which when burned combines with the oxygen in the air to form carbon dioxide, while other impurities are burned away in the process. This technique allowed for the ore to be melted, and combined with carbon, which formed a primitive form of iron. This primitive form of iron was not as pure or strong as modern iron, and often would need to be weakened, in order to be more malleable.
The primitive iron smelting methods were improved in about 1400BC and the bloomery process was discovered. This method of smelting involved forced air stoves which increased the temperature to around 1000 degrees Celsius. With this process the iron was melted and allowed to cool into a solid. Bloomery iron was still impure and often suffocating, as bits of charcoal and other impurities would get lodged inside the iron. In 1200BC, the Chinese discovered a process called tatara which allowed for the impurities to be burned away, producing a much purer iron.
In Europe, during the early medieval period, The Taskers process, or Cementation Process, was developed. This process involved the use of hammers and bellows to smelt the ore. The ore would be mixed with charcoal and placed in a clay container. It would then be sealed and heated with a furnace. This furnace created a carbon monoxide which seeped into the ore, separating it into its metallic form and releasing the impurities. It was then fettled, which involved hitting it with a large hammer in order to improve its consistency and quality.
For centuries, the only available tool for refining iron was the furnace. In 1709, however, Abraham Darby invented an improved version of the furnace, known as a reverberatory furnace. This type of furnace was able to maintain a much higher temperature, allowing for faster and more efficient refinement processes. Reverberatory furnaces are still in use today and are used for a variety of production processes, including the refining of iron.
The modern process of refining iron, otherwise known as steel making, is still relatively the same as it used to be centuries ago. It begins with the extraction of iron ore, which is then heated in a blast furnace. This furnace separates the ore into its metallic form, while releasing impurities that are burned away. The metal is then cooled and shaped into a bloom, which is then worked in a forge and hammer to remove additional impurities. It is then reheated and added to a converter, where additional impurities are removed. Finally, it is finished by pouring the molten iron into molds and allowing it to cool.
Today, the refining of iron still utilizes modern technology to ensure efficient production processes. Many innovative advancements have been made in order to refine iron into a more malleable and uniform material. However, the principles remain relatively the same; refining iron continues to be a process that takes centuries of technology and refinements.
