The earphone at the London headquarters of Novacem Limited is always ringing . And really , it ’s not hard to see why . Novacem , which grew out of research conducted at Imperial College in the United Kingdom ’s capital metropolis and is still housed at the university , is develop a cement it say will be carbon paper damaging – which , as the name suggests , means that the cement actuallysoaks up more carbon dioxide than is emittedin its production . Hence all the earpiece calls from green - minded builders .
" mass love the idea and ring us up all the prison term and say , ' We ’re building this or that ; can I get the cementum ? ' " pronounce John Prendergast , Novacem ’s strategy and planning manager . However , not one person who has eagerly sought out cement from Novacem has hung up the telephone set happy . " Unfortunately , it ’s not the sort of projection you may turn around overnight , " say Prendergast . " There ’s a lot of science behind it and still more to do . " Prendergast says Novacem is hope to have a pilot product finished by 2014 .
Novacem is just one of a number of globose companies – including Calera in California and Canada ’s Carbon Sense Solutions – field these sorts of calls and , at least for the consequence , turning people away . But the fact that there ’s so much sake ingreen cementis a good denotation of why a host of companies and researchers are try out to make it a reality . And the grocery store for it could be potentially huge , because , candidly , stock Portland cement – which , when desegregate with water and other stuff , hardens into concrete , the omnipresent construction material – is so environmentally unfriendly . Indeed , the yield of cement alone accounts for 5 pct of homo - render carbon dioxide emissions , surmount only by some very obvious culprits , include the burning of fossil fuels for electrical energy propagation , shipping , and the manufacture of smoothing iron and steel [ source : Rosenwald ] . That percentage could well rise , too , as China and India continue their rapid industrialization and construction microphone boom .
Clearly , then , replacing carbon - retch cementum with a substitute that really reduces emissions would be a wonderful benefit . Read on to discover about unlike approaches to address this very large undertaking .
The Quest for Carbon Negative Cement
Before taking a expression at the approach Novacem and other environmentally friendly cement companies use , have ’s examine how veritable old Portland cement is made . And by old , we really do mean old : The appendage for making Portland cement was discovered in the early 1800s by an English stone mason and has essentially remained the same ever since [ source : Schenker ] . In a nutshell , the 3 billion tons of cementum that get transformed into 30 billion tons ofconcreteeach year are produced by first digging up limestone , which is primarily made up of the cadaver of nautical animals [ source : Schenker ] .
transform the geezerhood - old sea wight casing that make up limestone into cement does two thing that lead to substantial carbon emission . First of all , the limestone must be ignite to a temperature of more than 2,500 degree Fahrenheit ( 1,371 degree Celsius ) to translate it into cement , a procedure that obviously requires the expenditure of a large amount of dodo fuels [ generator : Prendergast ] . At the same time , limestone releases a important amount of carbon – calcium carbonate is embedded in limestone – when it is inflame to such high temperatures . In sum , the traditional plan of attack to make Portland cement emits almost 1,800 pounds ( 816 kilograms ) of carbon dioxide for each gross ton of cementum made [ source : Schenker ] . According to many scientist , those increase carbon emissions are in turn cue awarming of Earth ’s climateand a host of adverse impacts , such as more severe weather , melting glaciers and rising sea stratum .
By contrast , companies creating carbon negative cementum use different raw materials and less energy . While the exact process and ingredients are proprietary , this is what Novacem will uncover : Rather than using limestone , the troupe relies on what are known as magnesium silicate , which come from olivine , talc and serpentine . significantly , magnesium silicates have no carbon embedded in them , which imply there are no emission when they are heated . There ’s another benefit in using Mg silicates alternatively of limestone as source material : They only need to be heated to about half the temperature of limestone so as to produce cement . A dispirited temperature , of course , means that less fossil fuels are needed for the process to mould – and that few emissions are produced along the way .
There ’s one more facet to the process of piddle Novacem ’s cementum that takes it from just being less harmful emissions - fresh to actually being carbon negative . In purchase order to make all the ingredients indurate into cement , Novacem tally atomic number 12 carbonates , which are produced by combining carbon dioxide and some other ingredients . Although it ’s a bit complicated , the lowdown is this : contribute carbon paper dioxide to the cement that would otherwise be let out into the atmosphere makes it carbon negative . Indeed , Novacem think that each net ton of cement produced could actually draw one - tenth of a ton of carbon paper dioxide [ source : Rosenwald ] .
With support from the British government and Laing O’Rourke , one of the prominent mental synthesis company in the country , Novacem is in all likelihood the high-pitched - visibility rig prosecute carbon damaging cement . But , as mentioned on the previous page , it ’s not the only one . In California , for example , a company called Calera has also received backing from the Union Department of Energy and prominent venture capitalist Vinod Khosla for its efforts . In pith , what Calera does is literally take the carbon dioxide emissions being spewed out of a major power industrial plant and mix them with weewee and other factor in ordering to make carbonates that go into cement . Calera already has a pilot burner operation in California and , in 2011 , announced an arrangement to build a cement factory next to a coal plant life in China .
Read on to see what difference carbon copy disconfirming cement could make – and what challenge subsist for it to become ubiquitous .
Carbon Negative Cement Opportunities and Challenges
Although Novacem ’s research cause have yet to produce cement that ’s really used in any expression task , John Prendergast has ambitious design for the product ’s future tense . " The bearing is to modernise a cement that can completely replace Portland cement , " he tell . In other words , he hop any undertaking that currently use received cement could seamlessly sub in Novacem ’s offering . interchange one of the great sources of carbon dioxide emission with a product that actually removes carbon dioxide from the environment would obviously be a very beneficial step forward .
There are a host of hurdle race , however , that any of the producers of carbon indifferent or damaging cementum will have to overcome . Perhaps most significant is just the manufacturing of a reliable product that can , in fact , take the place of Portland cement – this , of course of study , will only truly be try out once the companies reveal their cement for commercial-grade applications . Although , according to Prendergast , Novacem has intimate solvent that indicate it will be able-bodied to produce a cementum that is every act as substantial as Portland cement .
But other questions bulk large as well . For C negative cementum to really substitute its much dirtier counterpart , all of the raw materials for its product must be tinny and abundant enough to contend with Portland cementum on a cost footing . Calera , for illustration , has been criticized because its process necessitates entree to rarefied and expensive alkali deposits – an accusation the company dispute [ source : Romm ] .
For its part , Novacem attest that access to the raw materials it requires is not a potential barrier at all . Nor , says Prendergast , is cost . In other words , before long after getting up and running , he expects that Novacem cement will have about the same cost tag as Portland cementum . " Initially , you necessitate to build up a few plants before you get price para , " he says . " Our processing is different , but the applied scientist we have looking at the process so far approximate that the costs would be about the same . "
toleration by the building manufacture and regulator could come as the intersection proves itself in the marketplace . Then again , if carbon negatively charged cement can be produced at the same price and with the same character of Portland cementum , it ’s hard to imagine that it wo n’t finally be embraced .
