Environmental Impacts of Concrete and its Solution | Civil Mentors

 💚 Cre: Civil Mentors | Environmental Impacts of Concrete and its Solution

1. Reading comprehension:

Growing concerns about the environment and climate change, in particular, have highlighted another major problem with concrete: After transportation and energy, cement production is the third biggest source of carbon dioxide emissions. That's partly because the process of making cement releases a lot of carbon dioxide, but also very importantly because of the enormous amount of cement and concrete used worldwide. 

Carbon dioxide is released in two quite different ways: 

First, because of the fossil fuel energy used during the manufacture of cement; 

Second, because cement is produced when calcium carbonate turns to calcium oxide, releasing carbon dioxide in the process. 

Concrete relies on cement, so it's anything but a sustainable material, which worries engineers, in particular because they tend to be very environmentally conscious. Since carbon dioxide is released in two ways during cement production, it follows that there are two ways of making more environmentally-friendly concrete. 

Historically, since the Industrial Revolution, much of humankind's energy has come from burning coal, which releases more greenhouse gases than other fuels, and traditionally cement kilns were coal-fired too. 

Switching them from coal to natural gas is one solution since gas releases less carbon dioxide for a given amount of energy. Making cement kilns more efficient reduces the total energy they need, which also reduces their carbon dioxide emissions. 

The other solution is to reduce the amount of cement in the concrete mixture by using recycled materials, such as fly ash from incinerators. 

Another exciting prospect is the development of concrete that doesn't use calcium carbonate at all. Instead, the carbonate is made by bubbling carbon dioxide from a power plant through seawater. This has an overall environmental benefit since it takes the harmful waste CO2 emissions from power plants and turns them into very useful concrete instead. It's a kind of carbon capture and storage. 

Another environmental drawback of concrete comes from its use of aggregates, which have to be quarried often from environmentally sensitive areas such as river valleys. Using recycled aggregates (including recycled concrete from old demolished buildings) is a possible solution here.

2. Listening & Speaking

3. Role-playing

1. What aspect of the construction industry affects the environment?
2. The cement manufacturing industry ranks in terms of carbon emissions?
3. Why have such a great amount? 
4. How is Carbon dioxide released?
5. Why do people know about the impact of cement production but still use it?
6. What fuel is used in the cement kiln?
7. Is there any way to minimize the CO2 during cement production?
8. Can we reduce the amount of cement in the concrete mixture by using recycled materials?
9. Another exciting prospect is the development of concrete that doesn't use calcium carbonate at all, how does it work?
10. What is the environmental drawback of concrete coming from its use of aggregates?

4. Make your own speech with the below words:

concerns, carbon dioxide, emission, enormous, fossil fuel, calcium carbonate, calcium oxide, sustainable, conscious, cement kiln, coal-fired, fly ash, incinerators, bubbling, power plant, drawback, river valleys