This document discusses using biotechnological processes to increase rates of silicate weathering and limestone formation to store carbon dioxide from the atmosphere. It proposes a two-stage anaerobic digestion system where acidogenic bacteria convert organic matter into carbon dioxide in one stage, and methanogenic archaea convert the carbon dioxide into methane in a second stage. The carbon dioxide is also used to form carbonate minerals like limestone for long term carbon storage. The document outlines using the residues from this process to produce biogenic cement for re-use in construction and agriculture.

1. Shiva&Salek&
1"

3. 3"

4. 4"

5. 5"

6. Silicate&minerals&
e.g.&acidic&condi4ons&&
Limestone&
e.g.&alkaline&condi4ons&
+ CO2
6"
e.g.&acidic&condi4ons&&
e.g.&alkaline&condi4ons&

7. Using&biotechnological&processes&
increasing&silicate&weathering&and&
limestone&forma4on&rates&
7"

8. 8"
CO2&storage&efficiencies&of&two?stage&
biological&processes&

9. Two-stage anaerobic digestion system
9"
Limestone

10. Acidogenic Methanogenic
Mine
Silicate Mineral
Carbon containing
Wastewater
Re-use in
Construction/
Agriculture
Improved Biogas
Synthesis
Natural Gas
Carbonate
Mineral
Two-stage
Anaerobic digestion
10"
Limestone
Biocement

11. Acidogenic Methanogenic
Mine
Silicate Mineral
Re-use in
Construction/
Agriculture
Improved Biogas
Synthesis
Natural Gas
Carbonate
Mineral
Two-stage
Anaerobic digestion
11"

12. Acidogenic Methanogenic
Two-stage
Anaerobic digestion
12"

13. 13"
CH4
CO2
Component& SiO2& CaO& Fe2O3& P2O5& MgO& Al2O3& Na2O& Cl& MnO&
Organic&
reactant
TX?100&
surfactant
(wt.%)"
AD&Residue&
Chemical&grout
51.8 46.1 0.73 0.46 0.26 0.21 0.12 0.1 0.1 0.521 0
50270 0230 123 0 123 325 20230 0 022 426 0.1
Limestone
Biocement

14. 14"
Prac7cal"applica7on"of"CaCO3"in"
biotechnological"processes"

15. 15"