Question

The important advantage(s) of Lintz and Donawitz (L. D) process for the manufacture of steel is (are):
(A) the process is very quick
(B) operating costs are low
(C) better quality steel is obtained
(D) scrap iron can be used

Answer 1

Hint: Try to recollect what is Lintz and Donawitz (L. D) process is. Brush the instrumentation part used in this process to obtain the answer.

Complete answer:
-Lintz and Donawitz (L. D) process for the manufacture of steel is a very important commercially used manufacturing process of steel.
-In India, a steel plant at Rourkela uses this process in the manufacturing of steel.
-In this process, scrap and pig-iron both are used along with flux in the L.D. convertor. The converter is an instrument or we can maybe call it a digester having lining refractory made up of magnesium oxide, MgO and calcium oxide, CaO.
-When oxygen gas is passed at 4-12atm pressure into the converter, a temperature of 2000-2500$^{\circ }C$ range is produced. At this temperature, impurities from iron like carbon, silicon, manganese, etc. which is known as slag, get separated and pure iron is obtained.
-Pure iron is then mixed with an alloy containing iron, manganese and carbon to produce better quality steel.
-Therefore, the important advantages of Lintz and Donawitz(L. D) process for the manufacture of steel are:
(A) the process is very quick
(C) better quality steel is obtained
(D) scrap iron can be used

Note:
Lintz and Donawitz(L. D) process is commercially used even today for manufacturing steel. Although scrap iron can be used in this process, a considerably larger amount of molten pig iron is required to obtain a good yield of pure iron.