Consider the following statements:Studies indicate that carbon dioxide emissions from cement industr

Question

Consider the following statements:Studies indicate that carbon dioxide emissions from cement industry account for more than 5% of global carbon emissions.Silica-bearing clay is mixed with limestone while manufacturing cement.Limestone is converted into lime during clinker production for cement manufacturing.Which one of the following is correct in respect of the above statements?

Accepted Answer

The high-temperature process for manufacturing cement, the all-important glue that binds the components of concrete, accounts for roughly 8% of the world’s anthropogenic carbon dioxide emissions and consumes 2–3% of the global energy supply, according to the International Energy Agency. The method calls for heating powdered limestone, a widely available, inexpensive material, and clay to roughly 1,450 °C in a kiln. The high-temperature process, known as calcination (clinker production), converts calcium carbonate (CaCO3), the principal component of limestone, to calcium oxide (CaO), or lime, releasing CO2. That simple reaction, which is key to making cement, is the source of about half the CO2 emissions in cement manufacturing. Also, mixing silica-based clay with limestone during cement production leads to the release of CO2. This occurs because there is use of energy for this process and it releases CO2 gas. Hence, Both Statement II and Statement III are correct and both of them explain Statement I.