The correct answer is: B. In open-hearth process, the furnace heats the steel.
In the open-hearth process, molten pig iron is heated in a furnace with a mixture of air and limestone. The oxygen in the air reacts with the impurities in the pig iron, such as carbon and silicon, to form slag. The slag floats on top of the molten steel and can be removed. The molten steel is then poured into molds to form ingots.
The basic Bessemer process is a type of steelmaking process that uses a converter to remove impurities from molten pig iron. The converter is a large, pear-shaped vessel lined with a basic refractory material, such as dolomite or magnesite. Molten pig iron is poured into the converter and air is blown through it at high pressure. The oxygen in the air reacts with the impurities in the pig iron, such as carbon and silicon, to form slag. The slag floats on top of the molten steel and can be removed. The molten steel is then poured into molds to form ingots.
The Siemens process is a type of steelmaking process that uses an electric furnace to melt pig iron and scrap steel. The furnace is lined with a refractory material, such as magnesite or dolomite. Molten pig iron and scrap steel are charged into the furnace and heated to a high temperature. The impurities in the pig iron and scrap steel are oxidized by the oxygen in the air and removed as slag. The molten steel is then poured into molds to form ingots.
In conclusion, the correct answer is: B. In open-hearth process, the furnace heats the steel.