In carbonate acidizing, acid dissolves rock to create a high permeability channel called wormhole.
In carbonate acidizing, acid selectively flows into the high permeability zones to dissolve the rock, leaving the low permeability zones untreated.
Carbon enters the ocean as atmospheric carbon dioxide dissolves into the surface layers and is converted into carbonic acid, carbonate, and bicarbonate: CO2 (aq) + H2O \rightleftharpoons H2CO3 \rightleftharpoons HCO3− + H+ \rightleftharpoons CO32− + 2 H+.
pH of an aquatic system mostly depends on the presence of carbonate, bicarbonate, carbonic acid, and free CO2 in water (Wetzel 2001).
Carbon dioxide, bicarbonate, carbonic acid, and carbonate are key metabolites in all living systems, and the equilibrium of these different forms in living cells is important for proper physiological functioning.
At some point, the AGR and the non-carbonate acid neutralisation rate (ANRnc) will be similar.
This result is validated by δ13CDIC values (−9.8 to −3.7‰ VPDB) which represents a mixture of DIC produced by the following weathering pathways: (i) carbonate dissolution by carbonic acid (−8.25‰) > (ii) silicate dissolution by carbonic acid (−17‰) ≈ (iii) carbonate dissolution by sulfuric acid derived from the oxidation of sulfides (coupled sulfide-carbonate weathering) (+0.5‰).
Generally, the DIC in karst groundwater is dominantly derived from carbonate dissolution by carbonic acid.
As oxygenator introduces carbon dioxide that decrease water pH gets in contact with calcium shells, this hardens the water by producing soluble calcium bicarbonate (carbonic acid + calcium carbonate -> calcium bicarbonate).
This study presents experimental results on the reaction kinetics of dolomite with fresh and spent acid in carbonate acidizing.
