Hydrochloric acid, dolomite dissolution

The dissolution of dolomite, calcium magnesium carbonate, in hydrochloric acid is a reataion of particular importance in the acid stimulation of dolomite oil teseivoirsd The oil is contained in pore space of the carbonate material and must flow through the small pores to reach the well bore. In matrix stimulation, HCl is injected into a well bore to dissolve the porous carbonate matrix. By dissolving the solid carbonate the pores will increase in size, and die oil and gas will be able to flow out at faster rates, thereby increasing the productivity of tbe well. The dissolution reaction is... 

Lund, K., H. S. Fogler, and C. C. McCune. 1973. Acidization I The dissolution of dolomite in hydrochloric acid. Chemical Engineering Science. 28 691. Lund, K., H. S. Fogler, and C. C. McCune. 1975. Acidization II The dissolution of calcite in hydrochloric acid. Chemical... 

Reaction with aqueous acids. In general, limestones react readily with adds and are used for acid neutralisation. High calcium limestones react readily with dilute hydrochloric and nitric acids at ambient temperatures, whereas dolomite and dolomitic limestones only react readily when the dilute acid is heated. The reaction of limestone with sulfurous acid (formed by the dissolution of sulfur dioxide in water) is the basis of a flue gas desulfurisation process (see section 12.5.2). The reactions with acids which form insoluble or sparingly soluble calcium salts (e.g., sulfurous, sulfuric, oxalic, hydrofluoric and phosphoric acids) are inhibited by the reaction product. 

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