Concrete with & # 39 is a material made on the most widely used human history. Only water surpasses it as the most consumed resources on the planet.
But although -The key ingredient in cement concrete, has the form of a number of buildings around us, it also leaves a huge carbon footprint.
it Source about 8% emissions dioxide Carbon dioxide (CO2) in the world, the center of British analytical center Chatham House.
If the cement industry was a country it would be the third largest emitter in the worldFor China and the US It is emitted more CO2 than aviation gasoline (2.5%), and not far from the issue of global business in agriculture (12%).
The leaders took part in the cement industry in these days UN Climate Change Conference, COP24, which was heldor PolandIn order to find a way to meet the requirements before the & # 39 are to the Paris Agreement.
Under the agreement, the annual emissions of cement They must provide at least 16% 2030.
For those who hate the concrete, as the key material in most buildings, parking lots, bridges and dams have allowed the construction of some of the architectural worst monsters of the world.
In the UK, it has helped a great development after the Second World War, but today still asleep disagreed.
But concrete is also the rate at which owes its existence to some of the most impressive buildings in the world.
orSydney Opera HouseIn Australia, the Lotus Temple in Delhi, India, Burj Khalifa in Dubai, O & # 39; the United Arab EmiratesOr delightful Pantheon in Rome, Italy, with a concrete dome without the world's largest carrier. All owe their shape to this material.
Formed with a mixture of sand and gravel, cement and water conglomerate, concrete recognized architects and builders as one of the best building materials.
"It's affordable, it can happen almost anywhere and has all the rights to build a solid building of infrastructure or structural quality, "says Felix Preston, Deputy Director of the Research Department of Energy, the Environment and Natural Resources Chatham House.
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And this is that, despite the durability of the known problems with using steel bars, which can crack the concrete from within, Concrete is still a & # 39 is the most widely used material in the world.
"Construction without it, although it is possible, it is a challenge," says Preston.
Growth cement industry
These unique properties, especially those who contributed to the increase in global cement production of the 1950s in this stop, Asia, and China has increased the price for the majority of growth since the early 90-ies of the last century.
production increased in more than thirty times since 1950 and nearly four times since 1990, China used more cement in the period between 2011 and 2013 the United States of America throughout the twentieth century.
Now that the Chinese consumption seems to be stabilizing, it is expected that most of the future growth in construction occur in emerging markets in Southeast Asia and countries in sub-Saharan Africa, movable rapid urbanization and economic development.
Projections show that the building footprints in the world will double in the next 40 years, which requires the production of cement increased by 25% up to 2030 person.
But despite the widespread presence, environmental credentials of concrete were subjected to further analysis over the past two decades.
Production of Portland cement, the most common type, involves not only developing car & # 39; erav in the car & # 39; JerohamThat pollute the air emissions of dust, but also requires the use of a huge ovens which consume large amounts of energy.
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Cement production chemical process He also admits surprisingly high levels of CO2.
"action is required"
Sector progressed: energy efficiency of new plants and the replacement of fossil fuel by burning waste amounted average CO2 emissions per ton production decrease by 18% over the past decades, according Chatham House.
The newly created Global Cement and Concrete Association (GCCA, its English abbreviation), which is currently This represents about 35% of the cement production capacity the world and focuses on sustainable development, and participates in meetings of the COP24.
Director General of the organization, Benjamin Sporton, said the organization recently with "& # 39 is demonstration of commitment to the industry sustainability, including measures to combat climate change. "
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GCCA should publish a set of guidelines for sustainable development, which must follow its members.
"On the & # 39; yadnavshy global players to reach out and develop a detailed program of work, we can help a sustainable future for cement and concreteAnd for the needs of future generations, "says Sporton.
But, despite promises, Chatham House notes that the industry is reaching its limits, what you can do with the existing measures.
If the industry is hope for fulfillment of its obligations, as reflected in the Paris agreement on climate change in 2015, you should review the cement production process, not only to reduce the use of fossil fuels.
Clinker, especially pollutants
This process of manufacturing cement clinker, a key component of the cement formed after calcination of limestone and clay, which produces the largest quantity of CO2 in the production.
In 2016, world production of cement created around 2.2 billion tonnes of CO2That is equivalent to 8% of the world about the & # 39; volume. More than half came from the hardening process.
Along with the heat of combustion, 90% of sector emissions can be attributed to the production of clinker.
Because of this, Chatham House expert argues that the sector urgently needs to follow a number of CO2 reduction strategies.
Additional efforts in the field of energy efficiency, reducing the use of fossil fuels and the search and storage of carbon will help, but can do little alone.
"We have a long way to close this gap," says Preston.
What the industry really needs to do is to step up efforts to to produce new types of cementHe says.
In fact, the development of low-carbon cements and new types of cements can eliminate the use of clinker completely.
Ginger Krieg Doser, co-founder and CEO BioMason, company, trillions of bacteria used for the production of bio-concrete bricksThis is one of the companies that are trying to get more support for alternative cements.
The technique, which involves placing a sand mold and injected microorganisms initiate a process similar to that creates coral.
"I've always been fascinated by the cement and marine structures," says Krieg Dosier, who began to explore alternative manufacturing bricks with a friendly 10 years ago nature.
Their findings led her to create her own material, which, after several years of development, requires only four days to be manufactured.
The process takes place in the open air, without the need for fossil fuels or hardening, the two major sources of CO2 emissions in cement industry.
Krieg Digest believes that a "green" cement technology, it has developed to offer a solution of emissions problems in the sector.
"Traditional production of Portland cement will continue to produce CO2 as a result of a chemical process behind," he says, adding that instead of resorting to carbon capture and storage, we need to invest more in Methods active removal of carbon from the atmosphere.
"Alternative cements and technology conglomerate for CO2 capture."
With alternative cement, another "translates" force, too, begins to drive change. Digitizing, machine learning and raising awareness of sustainability affect the culture of the cement industry.
"In particular, it is changing due as people want to live, but also our ability to develop new structures and innovative and try them with computer models, "says Preston." There is also the ability to create more cheap things with robots, with the help of automation. "
But changing processes fast enough to meet the obligations of the cement industry will be a problem.
The sector is dominated by a small number of producers, reluctant to change the business model. Architects, engineers, contractors, and customers also careful with the use of new materials in buildings.
"This sector is hard to change, starts to beat these profound changes are starting to see in the building," says Preston.
But since very few low-carbon cements reach the marketing stage, and no one refers to the scale of the industry, it seems likely to be require government support stable for a long time.
If governments do not put pressure on the industry or to provide funds, it may not be possible to see in the market the next generation of cements in a timely manner.
But Krieg Dosier thinks there is reason for optimism.
"I think that the construction industry is approaching the point where Alternative materials generalize adoption"He says.
"This is partly due to the demand in the market, with the & # 39;. The emergence of other innovative technologies and increasing concern about climate change"
Preston said it is very important that the government and industry to act quickly, at the time when the expected increase in global development, but to reduce CO2 emissions.
"There is an urgent need to build high-quality housing and affordable"He says.
"There is a need for new infrastructure. We can only straighten this cycle when we can exponentially improve the way we build, so that these The buildings are constructed primarily with clean emissions as close as possible to zero".
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