Concrete and the Environment
The impact of mankind on climate change/climate destruction is becoming more and more evident. This is mainly caused by CO
2 emissions.
All over the world, concrete is the most commonly used building material. In spite of the fact that concrete is very robust, there will come a moment for it to be superfluous. To produce concrete, cement is needed and to make cement, large quantities of Calcium Carbonate (CaCO3) are required. In the Netherlands this is mined in Maastricht as ‘marl / limestone’. It is not commonly known, though, that marl / limestone consists of 44% of CO2.
During the high-energy treatment process to make cement from marl / limestone, large quantities of CO2 are released (100% dry CaCO3 → 56% CaO + 44% CO2).
Due to the immense quantities of CO2 released from marl / limestone, together with the CO2 from the fossil fuel for the cement kiln and the energy to grind cement, 1kg CO2 is released to make 1 kg of cement.
According to their own statements, the cement industry alone produced 5,000 million tonnes (5 billion tonnes) of cement in 2017, equivalent to an emission of 5,000 million tonnes of CO2. This is more than twice the amount of CO2 released by all aircraft and amounts to more than 9% of man made CO2!
All this causes the climate change to take place sooner than expected. It is obvious that this accelerated climate change will not only have disastrous consequences for a large proportion of the world population but will also prove very costly to keep under control (let alone to reduce its impact).
Making the concrete chain circular by using the SmartCrusher will first of all slow down the advance of climate change.
In addition to the enormous environmental impact to produce concrete, the robustness of the material is such that it does not just disappear (wood rots away, iron is eaten away by rust, but concrete will remain robust for centuries).
One of the aims of SmartCrusher bv is to design, develop, build and market SmartCrushers. By using SmartCrushers concrete rubble will prove to be a better raw material for new concrete than original raw materials.
By using urban mining, SmartCrusher bv will not only make the concrete chain circular but also much more environmentally sound.
Concrete rubble can be regarded as the basis for low-carbon, environmentally sound cement, or even as the raw material for CO2 neutral cement.
Moreover, the cement in concrete will never completely react with the mixing water, which means that all the cement is hydrated to become cement hydrate, also called cement stone. This new cement obtained from concrete rubble can straight away be used for a second time.
Sustainable Concrete Recycling - Closing the Loop
1
Making 1 kg of Portland cement from marl/limestone = 1 kg of CO2. (5 Billions tons in 2017)
2
For concrete construction, roughly 3x as much CO2 as all aircraft!
3
In all the concrete rubble is still roughly 50% new, reactive cement!
4
SmartCrushers free that new cement from concrete rubble and is immediately usable again.
5
The cement used (cement hydrate) is a CO2-free marl / limestone substitute for the production of new cement or
6
to be worked up as a binder or mixture improver.
7
SmartCrushing: Without marl / limestone quarry; dust-free and without harmful emissions new cement and concrete.
8
Sand and gravel from SmartCrushers is directly on location and ensures better concrete with less cement!
9
SmartCrushing reduces roughly 2.5 billion tons of CO2 per year.
10
Urban mining with SmartCrusher halves the cost of new concrete!
11
Worthless sludge by washing.
12
Large amounts of valuable sand and gravel with a lot of CO2.
13
Downgrading as road foundation.
14
Worthless crushed sand.
15
Concrete granulate in concrete requires more cement.
