Iron Ore Processing With Thomas Process

  

Iron Ore Processing With

Thomas Process

Iron ore smelting process carried out by the reaction of compounds as chemical elements through the warm-up for the opening of the structural bonding of metal atoms in order to obtain iron ore with high iron content.

Basically, the various methods in the process of making this material element is the process of refining iron from a variety of harmful elements, therefore in the process of making material by using this converter system is one of the process of purification or separation of iron by using the vessel as a means of heating (melting) of iron The crude.

Thomas is the process of development of oxidation methods that use a converter. Oxidation method that blows air into the molten crude iron are placed in the vessel (ship) as the converter through this process turned out the various elements contained in the raw iron to move. Converter is a steel tube with wall-coated and resistant to high temperature and placed in a container that is formed in such a way that can be modified in a vertical position or horizontal position at the mouth of which lies on the side or above and even below. Position - This position is required for charging, blowing and pouring the results of purification of carbon dioxide

Converter for a capacity of 25-60 tons Oxidation method. Pig iron from the furnace in which the pour into sprayed Oxygen Converter. (see Figure 1).

This process is found in England by Thomas Gilchist Sydney in 1878 with his cousin Percy Gilchrist managed to overcome the excess phosphorus in pig iron. this process is the beginning of the development of steel industry in Britain until after the second world war

Thomas process is a process of refining crude iron Oxidasi using the exhaled air into the bottom melelui Converter converter by adding limestone (Limeston) or the Dolomite converter so that the wall be able to reduce excess bases and Phospor by removing the element with the slag. Thomas process suitable for making steel from pig iron from iron ore-rich phosphorus content.

Purification process is done by first melt the raw iron into a converter which is in a horizontal position and then the converter changed his position on the vertical position and in this position pressurized air exhaled through the base

140 KN/m2 converter into liquid crude iron. In particular Thomas converter do that is a white pig iron pig iron containing from 3 to 3.5% C and 0.2 - 0.5% Si. Before the liquid iron is inserted into the first converter is loaded additional material to bind calcium (P) and (Si) so that the crust (droppings). This additional material should be pretty much 12 -18% of the load converter, so it should be able to ngikat Si and P, because if less silicon oxide (SiO2) will damage the lining of the kitchen with the reaction. CaO + SiO2 II CaSiO3. After Si, Mn, and C will be burned first, then the elements of P. As a result of steel that produced still contains elements of a very high P (0.08%). Similarly, since the sprayed air containing nitrogen element is also high (0.03%). High levels of these two elements are capable of lowering properties of cold steel, the results of Thomas and oxide process P will react with CaO into calcium phosphate. P2O5 + CaO II Ca3 (PO4) 2 Calcium phosphate is a slag which is very valuable because after going through further processing can be used as plant fertilizer. Then oxidized and the return of substances such as charcoal made on the Bessemer process. Iron happened Converters Thomas worked with Walls machines (grinder) into steel plates.

         Lining the inner wall made of stone or dolomite refractories can [calcium and magnesium carbonate (CaCO3 + MgCO3)], processed iron-containing pig iron white P between 1.7 to 2%, Mn 1 to 2% and Si 0, 6-0,8%.

Working system of the Thomas process
1. This purification process is done first Crude iron melt into the converter that is in a horizontal position
2. Then change the converter in a vertical position and in this position pressurized air 400 KN/m2
3. in exhaled air through the basic converter into liquid crude iron
4. After that stop blowing oxygen and then take test samples from molten metal before the freezing process to determine the content of carbon, phosphorus, and sulfur contained in the liquid metal
5. The elements Si, Mn and C will be burned first, then the element P
Function
• Reduce content Phospor
• Reduce excessive carbon content
• Slag (Calcium Phosphate) from this process if in doing further can be used as fertilizer
• Eliminate the weak elements of nitrogen or substances
The advantage of Basic Oxygen Furnace
1. Using oxygen (O ²) of pure without Nitrogen
2. Fast Process
3. Low cost
4. Eliminate harmful content
The weakness of the process of Thomas
- Downhill able to shape the nature of the results of cold steel Thomas process
-After the process is complete, there is still liquid residue in the form of oxide.

Conclusion

From the discussion, it can be concluded that the process of thomas is one of the refining process of iron ore from the harmful elements to develop a method that uses oxidasi converter. Purification was done by blowing air from the bottom of the converter, and dolomite is added so that the walls of the converter is alkaline. Resulting in material quality. Thomas process faster, cheaper, and do not require nitrogen so it is more profitable than other purification processes.