العربية
Concrete Recycling Application Start,
There is a lot of talk about concrete recycling in the construction industry, and inspired by nature, the circular economy operates,
in a continuous process of production, absorption, recycling, self-management and naturally organizing itself.
Where waste can turn into supplies for the production of new products,
which is a very interesting concept,
but it faces some practical difficulties in everyday life,
both in the process of demolition and dismantling, and in the correct disposal of materials and waste.
This is due to the lack of technologies available to recycle or give new use to building materials.
About 40% of all waste generated on the planet comes from civil construction,
a large part of which can be recycled.
Cement is a particularly important material because of its large carbon footprint in production,
its ubiquitous presence and widespread use, and the difficulty of recycling or reusing it.
Until recently, we were able to break down demolished concrete structures that produce aggregates made up of smaller parts of concrete.
It is often used for restricted processes such as down rolling (in materials with a more limited scope of use than in the original materials).
Through a simple crushing process, the shrapnel is used as a base material for structures such as roads or other similar uses.
Due to the low quality of the secondary aggregate, the exchange rate for the raw materials is limited to about 30% -,
a very unsatisfactory level to ensure the desired quality of concrete,
due to the excessive amounts of cement and chemical additives it contains.
Also, through the patented reCO2ver process,
Sika has developed a highly efficient process to separate and reuse degraded concrete components and increase the quality of recycled aggregate.
Concrete Recycling Application Start
The process consists of a synergistic chemical-mechanical treatment of concrete demolition waste.
The technique involves the surface carbonization of the cement matrix (when carbon dioxide is dissolved in water or in an aqueous solution),
which is softened and removed by friction.
Through this process, freshly exposed surfaces are obtained, which are able to increase carbonization until obtaining cement-free aggregates.
Concrete or mortar demolition waste can also be separated into “secondary aggregates”
for recycling with a quality level similar to that of traditional raw materials; like a powder that can be used as a secondary raw material in various applications.
That is, old concrete is crushed into individual pieces (gravel, sand, limestone),
in a simple process that also sequesters about 50 kg of CO2 per ton of crushed concrete demolition waste.
Comparative tests have shown that structures built with new concrete with a recycled content perform similar to an entirely new structure.
Thus, the technology provides a 40% reduction in water use and up to 25% in cement,
in addition to the use of concrete waste to sequester carbon dioxide in the atmosphere.
Almost 300 million tons of old concrete is produced each year, in the five largest countries in the European Union alone.
With complete recycling of these materials, up to 15 million tons of carbon dioxide emissions could be captured,
in a new process that has the potential to benefit people and the environment.
By saving natural resources and achieving a viable concrete recycling technology,
the company is able to transform this material from a pollutant into an important agent of change for the world.
