Steel slag can be the material for which of the following?

1. Construction of base road

2. Improvement of agricultural soil

3. Production of cement

Select the correct answer using the code given below:

(a) 1 and 2 only

(b) 2 and 3 only

(d) 1, 2 and 3

6. Ans: d

Explanation:

Steel Slag:

The slag produced at blast furnace during pig iron manufacturing is called blast furnace slag. The slag produced at steel melting shop is known as steel slag. To produce steel, removal of excess silicon and carbon from iron is achieved through oxidation by adding limestone and coke.
Lower grade ores yield much higher slag fractions, sometimes as high as one tonne of slag per tonne of pig iron produced.
The iron content is the major basic difference between BF slag and steel slag. In BF slag, FeO is around 0.70%, whereas, in case of steel slag, total iron content varies from 16 to 25%.
Ferro Scrap Nigam Ltd (FSNL), a wholly owned subsidiary of MSTC Ltd (public sector company) undertakes the recovery and processing of scrap from slag and refuse dumps in the nine steel plants.

Uses of Steel Slag:

Slag based on their types, has different uses. The air-cooled BF slag is crushed, screened and used mainly as road metal and bases, asphalt paving, track ballast, landfills and concrete aggregate.
The expanded or foamed slag binds well with cement and is used mainly as aggregate for light weight concrete.
Granulated BF slag is used as a pozzolanic material for producing portland slag cement.
It is also used for soil conditioning. BF slag is used in making mineral wool for insulation purposes.
Steel slag has found use as a barrier material remedy for waste sites where heavy metals tend to leach into the surrounding environment. Steel slag forces the heavy metals to drop out of solution in water run off because of its high oxide mineral content.
Steel slag has been used successfully to treat acidic water discharges from abandoned mines.
It has shown potential for use as a raw mix component up to 10% in the manufacture of cement clinker.
Steel slag can also replace granulated blast furnace slag up to 10% in the manufacture of Portland Slag Cement.

Hence, option d is correct.

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