Tuesday, March 12, 2013

Replace Charcoal With Coke In Iron Melting

Iron is a grayish-white magnetic metal. Iron is mined from its ore, which is impure because it contains elements such as oxygen. It is melted in a furnace supplied in the presence of carbon-based reducing agents such as coke or charcoal to remove oxygen to give pure iron. Charcoal often can be used if the ore has a high melting point, and it can be replaced with coke when iron begins to melt.


1. Prepare a furnace. Build the walls of a furnace using heat-resistant brick such as cement, chamotte bricks and gypsum block. You can also use a high-melting-point ceramic of silica or alumina. Leave an opening at the top and two at the bottom for feeding in fuel and for blowing air into the furnace using a bellow.

2. Place charcoal into the furnace through the hole at the bottom. Light the charcoal. Put on your protective gloves, and allow fire to burn in the furnace to eliminate any moisture. Explosion can occur if moisture gets into contact with molten iron and charcoal.

3. Split the iron ore into small pieces with a sledgehammer. The smaller they are, the quicker they will melt. Scoop up the pieces using a cast iron pan and add them to the burning charcoal.

4. Insert the bellows into the furnace through the hole at the bottom. Use it to blow air into the furnace to ensure proper height of the fire and to prevent temperature from dropping. Use a cast iron pan to add more charcoal into the furnace.

5. Wear goggles and check if there is any bubble in the furnace to indicate whether the melting is taking place or not. Replace the charcoal with coke. Coke does not produce as much heat as charcoal but burns longer.

6. Scoop pieces of coke with the cast iron pan, and feed them to the fire. Continue blowing air into the furnace using the bellow. The pressurized heated air will make the coke burn faster, producing carbon monoxide to react with the heat to melt the iron further.

7. Stir the burning coke and the molting iron using an iron rod. Coke acts as reducing agent and removes oxygen from the molten iron. Allow the iron to melt completely for about 12 to 15 minutes.

8. Add small quantities of limestone to the molten iron and coke. (Limestone is added to remove slag or impurities from the molten iron). A mixture of limestone and impurities will float to the top of the molten iron.

9. Open the tap hole at the bottom of the furnace to allow the molten iron and slag to flow off. Once the molten iron cools, it will harden to form pure iron at melting point of 2757 degrees Fahrenheit.

Tags: molten iron, into furnace, cast iron, furnace using, hole bottom, blowing into, blowing into furnace