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:

[UPSC Civil Services Exam – 2020 Prelims]

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

Answer: (d)

Explanation:

• The production of steel slag is a by-product of the steel-making process and occurs during the separation of molten steel from impurities in furnaces. Steel slag, being one of the constituents of asphalt, is used in the construction of asphalt roads along with other materials such as sand, gravel, and bitumen produced by refineries. Thus, statement 1 is correct.
• Steel slag finds its application in various sectors like construction, paving, and agriculture. It can help to correct soil acidity as it contains nutrients that are beneficial for plants and acts as a silicate fertilizer providing silicon to them. Therefore, statement 2 is also correct.
• Steel slag is considered a viable raw mix component, replacing up to 10% of granulated blast furnace slag in Portland Slag Cement manufacturing. It has also been used successfully to treat acidic water discharges from abandoned mines. Hence, the statement 3 is correct.

Therefore, option (d) is the correct answer.