Biomimicry and Geomimicry with TecEco Concretes
Biomimicry and Geomimicry at Earthship Brighton in the UK
There is a way of removing CO2 from the air and potentially making money at the same time. Doing this will not happen because it is the right thing to do. It can only happen because it is profitable.
The key is to find ways of adding value to CO2 as otherwise there is no economic incentive to remove the gas from the air. Humans in a globalist world are "slaves to economics" and can not collectively do much without economic benefit. The longer term external factors that concern survival cannot be measured in markets and have for many years been disregarded.
Fortunately carbon is a component of many useful compounds. Both organic and many inorganic compounds contain atoms of it derived from new or fossil CO2. We need to figure out which of these compounds are or could be more useful and try and incorporate more of them into our industrial ecologies. TecEco and other members of the Global Sustainability Alliance have embarked on the ambitious Gaia Engineering project to develop tececologies that use more CO2 than they produce. Fortunately there is much other research happening in this area. Genetic modification of blue green algae so they produce cellulose is another example a promising innovation.
What we need is a process with huge flows involved and Gaia Engineering achieves this. TecEco's contribution has been to provide a way of using CO2 to cement together the built environment. The largest flows on the planet are of materials used to construct the built environment, so using carbonate in substitution makes a great deal of sense. Learning to use CO2 as a resource as do virtually all plants and animals is going to become the most important lesson of the century.
The idea of using carbonate is not new. There have been many previous epochs where the earth has warmed and much carbonate has been precipitated during these periods. As mentioned some 7% of the crust is carbonate sediment. Now we have such a big influence on the planet we are going to have to take the initiative and find economic ways to mimic nature and deposit carbonate on a similar scale to our emissions. Magnesium is the best choice of a binding atom and there are unlimited supplies in seawater. Using the new Greensols process from our alliance partner Greensols and waste acid the magnesium can be precipitated out as useful, and more importantly valuable carbonate. This process copies what has occurred naturally in the past and "geomimicry" is a new word akin to "biomimicry" invented by Janine Benyus that I have invented to describe processes that in such a manner mimic natural geological processes.
How Much Carbonate?
We make more concrete than anything else. If carbonates as suggested by TecEco were used instead of silicates as binders for concrete they would mimic the natural geological process of sequestering carbon.
Various authors have attempted to model the earths rock cycle whereby rocks are made and remade. Unfortunately nobody yet has come up with rates of sedimentary carbonate deposition, although approximations of oceanic uptake have been developed as a result of CO2 modeling. The interesting question is to what extent the flows involved by producing carbonate bound concretes would make a difference.
If concretes were held together by carbonates using Eco-Cements then some 15% of their mass would absorb CO2. If the gas is captured as source during the manufacture of Eco-Cements then there would be significant geomimicry of natural sequestration processes.
According to Richard Haughton[6] at the Woods Hole Institute, total global carbon cycle flows are:
Atmospheric increase |
= |
Emissions from fossil fuels |
+ |
Net emissions from changes in land use |
- |
Oceanic uptake |
- |
Missing carbon sink |
3.2 (±0.2) |
= |
6.3 (±0.4) |
+ |
2.2 (±0.8) |
- |
2.4 (±0.7) |
- |
2.9 (±1.1) |
Figure 1 - The Carbon Cycle (Haughton 2005) in billion metric tonnes or petograms
Converting to tonnes CO2 in the same units by multiplying by 44.01/12.01, the ratio of the respective molecular weights.
Atmospheric increase |
= |
Emissions from fossil fuels |
+ |
Net emissions from changes in land use |
- |
Oceanic uptake |
- |
Missing carbon sink |
11.72 (±0.2) |
= |
23.08 (±0.4) |
+ |
8.016 (±0.8) |
- |
8.79 (±0.7) |
- |
10.62 (±1.1) |
Figure 2 - The Carbon Dioxide Cycle (Haughton 2005) in billion metric tonnes or petograms.
From the above the annual atmospheric increase of CO2 is in the order of 12 billion metric tonnes.
If concretes were held together by carbonate, how much would we need to reverse global warming?
MgO + H2O => Mg(OH)2 + CO2 + 2H2O => MgCO3.3H2O
40.31 + 18(l) => 58.31 + 44.01(g) + 2 X 18(l) => 138.368 molar masses.
44.01 parts by mass of CO2 ~= 138.368 parts by mass MgCO3.3H2O
1 ~= 138.368/44.01= 3.144
12 billion tonnes CO2 ~= 37.728 billion tonnes of nesquehonite binder in concrete
This is much more than the current production of cement (2.1 billion tonnes), so total use of carbonation for binders would alleviate, but not solve the problem.
How much carbonate would have to be deposited to solve the problem?
MgO + H2O => Mg(OH)2 + CO2 + 2H2O => MgCO3
40.31 + 18(l) => 58.31 + 44.01(g) + 2 X 18(l) => 84.32 molar masses.
CO2 ~= MgCO3
44.01 parts by mass of CO2 ~= 84.32 parts by mass MgCO3
1 ~= 84.32/44.01= 1.9159
12 billion tonnes CO2 ~= 22.99 billion tonnes magnesite
The density of magnesite is 3 gm/cm3 or 3 tonne/metre3
Thus 22.9/3 billion cubic metres ~= 7.63 cubic kilometres of magnesite are required to be deposited each year. Compared to the over seven cubic kilometres of concrete we make every year, the problem of global warming looks surmountable. If magnesite was our building material of choice held together by TecEco Eco-Cement binders and we could make both without releases we would have the problem as good as solved!
Even though Greensols will produce magnesite, it will need to be reprocessed to be used as a binder and that is where the TecEco Tec-Kiln technology that does not release CO2 shines. Greensols, The TecEco kiln and TecEco-cements are all part of a tececology alliance members call Gaia Engineering. A whole host of related technologies, working together in what we call a tececology that reverse the flow of carbon and wastes were required to work the ecological pump we need to reverse the damage we have done.
The Gaia Engineering embraces a number of new technical paradigms and processes working together to solve global warming and waste problems by changing the flows involved. Gaia Engineering will work because combined correctly these new processes will allow people to make money using them.
If adopted on a large scale the Gaia Engineering tececology would sequester significant amounts of atmospheric CO2 and convert significant wastes to resources. Gaia Engineering is an agglomeration of new technologies including TecEco’s kiln technology and cements, carbon dioxide scrubbing technology, a seawater separation technology from Greensols Pty. Ltd and heat transfer and desalination technologies that can produce fresh water, a number of industrial commodity products including gypsum, sodium bicarbonate and various other salts as well as building materials based on magnesium carbonates that also utilize wastes. Each of these outputs uniquely provides revenue to help make the overall process economic.
How the MgCO2 cycle in Gaia Engineering TecEcology is Geo-Photosynthetic(mimicking Photosynthesis)
In 1796, Jean Senebier, a French pastor, showed that CO2 was the "fixed" or "injured" air and that it was taken up by plants. Soon afterwards, Theodore de Saussure showed that the increase in mass of the plant as it grows could not be due only to uptake of CO2, but also to the incorporation of water.
It followed that the process of photosynthesis achieves the following:
CO2 + H2O + light energy ---> (CH2O)n + O2
Respiration on the other hand consumes organic molecules and oxygen to produce energy and CO2.
Before the industrial revolution the processes of photosynthesis and respiration were essentially balanced. We burn fossil fuels for energy in a manner similar to respiration but we provide no process to remove the damaging amounts of CO2 that we introduce into the air. The Gaia Engineering tececology was designed for this purpose and could therefore be likened to an ecological pump with many features analogous with photosynthesis.
The diagram below summarises photosynthesis in terms of inputs and outputs. The explanation of the complex reactions that take place is for the purpose of comparison simplistic.
Magnesium ions are important in the chlorophyll molecule as their strong charge holds an electron cloud around a porphyrin ring that supplies electrons to the process. PSII as it is referred to is a photosynthetic process that splits water thereby supplying hydrogen ions and electrons to this cloud. These electrons pass through the process powering the Calvin cycle via NADP<=> NADPH in the PS1 process. The hydrogen ions are incorporated in glucose via the (ADP<=>ATP) cycle.
The MgCO2 and hydroxide/carbonate slurry process cycles in Gaia Engineering tececology depicted above similarly use magnesium compounds to fix CO2 as carbonates.
Both the Gaia Engineering and photosynthesis processes are powered by light and hence photosynthetic. Common to both are energy transfer mechanisms. In photosynthesis electrons move around the process whereas in the MgCO2 and hydroxide/carbonate slurry process cycles it is intended to use heat transfer technologies such as Newcomen engines.