New Sensation in Construction Industry #GreenConcrete
Geopolymer cement provides a viable alternative to Portland cement for use in concrete. To make conventional cement, you need to dig raw materials out of the ground and heat them to very high temperatures. You are essentially driving off CO2 molecules. The production of cement releases a lot of greenhouse gases, making it one of the top five pollutants. Cement manufacturing pumps around six billion tons of CO2 into the atmosphere every year.
Image Credit: Zeobond
An antibacterial geopolymer called Antibac, with potential in the construction industry has been developed. It is an inorganic resin that inhibits development, growth and reproduction of bacteria, yeasts and fungi; used as a cement, it can adhere to metal surfaces, ceramics or glass and inhibit harmful microorganisms. Researchers at the Universidad Michoacana de San NicolÃ¡s de Hidalgo (UMSNH) in Mexico used this antibacterial geopolymer to repel pathogens. Dr. Jose Carlos Rubio is the creator of the technology. The product is generating much interest amongst local polymer traders, with many predicting that its sales could be global.
It consists of clay and sea sand dissolved in an aqueous solution, using microscopic glass particles as a biocidal agent to enclose the antibacterial micro-crystals, without being able to leave the material and then subsequently removes them. This increases the antibacterial performance and it prolongs its effect for years. The product can be placed on any surface just like a construction paste, setting in just 24 hours. The main highlight of the developed technology is that its production is based on non-polluting industrial waste water, which does not release fumes or volatile organic compounds.
It is also ideal for use as an antibacterial coating particularly for surfaces in hospitals, restaurants or the food processing industry, but it can also be used in the home. Once solidified, the resin encloses antibacterial micro-crystals in its microstructure. When pathogens come into contact with the surface, they get stuck because of their high affinity with the micro-crystals, preventing contact transference. The pathogens can then be removed by existing diffusion or a cleaning product. Australia’s Wellcamp Airport was mainly built, using a geoplymer, making it the greenest airport ever built.
It costs less than $10 per square meter, making it cheap compared to current synthetic coatings. But universities cannot produce the 70,000 tons of geoplymer needed in Wellcamp airport. Both domestic and international partnerships are important for seeing these innovative ideas, translated into business success.
The University of Queensland’s Global Change Institute (GCI), designed by HASSELL in collaboration with Bligh Tanner and Wagners, is the world’s first building to successfully use geopolymer concrete for structural purposes.
Despite being the most viable substitute of traditional Portland cement, there are some disadvantages restraining customers from adopting geopolymer in the construction industry. Research into geopolymer to overcome some knowledge gaps regarding longer-term durability of embedded steel, creep behaviour is ongoing.
Experts from this industry proposed solutions on the special handling of geopolymer concrete and also on the hurdle of curing geopolymers at elevated temperatures.
A geopolymer is a chemical compound or a mixture of compounds that consist of repeating units of compounds like:
- Silico-aluminate (-Si-O-Al-O-)
- Silico-oxide (-Si-O-Si-O-)
- Alumino-phosphate (-Al-O-P-O-)
- Ferro-silico-aluminate (-Fe-O-Si-O-Al-O-).
These key players in the geopolymer industry:
These mineral compounds, prepared through geopolymerization, are formed at room temperature by the usage of industrial waste or with the help of by-products of other compounds.
According to Wizards Island research report, the Global Geopolymer Market has been estimated at USD 1,502.6 million in 2015 and is projected to reach USD 7,184.32 million by 2020, at a CAGR of 36.74% during the forecast period from 2016 to 2020. The market is expected to be driven by construction chemicals as well as pre-set products oriented industries such as bricks and slabs, sealants & grouts, and others. The customer base is across markets from buildings, pavements, embankments, tunnel linings, railway sleepers to repair and rehabilitation of pipes, flooring and wall cracks as well as fireproofing panels.
This could be an important breakthrough in the search for environmentally-friendly ways to control bacteria while preventing antibiotic resistance and resistant bacteria. One ton of cement releases approximately one ton of greenhouse gases! Sixty percent of emissions are due to transforming limestone, and the other 40 percent comes from using fossil fuels to heat the cement kilns to 2,732 degrees F (1500°C).