Well Stimulation Fracturing and Acidizing

There are also several types of fracturing fluid emulsions (including water- and oil-based emulsions) [47,48] and foams (including water-, oil- and alcohol-based 

Breaker 0.02 Break the gel after a suitable delay period 

Iron control 0.004 Prevent reactions with iron-containing minerals 

Acid-in-oil emulsion can extend the propagation of acid considerable distances into a reservoir because the continuous (oil) phase prevents or minimizes contact between the acid and the rock [1, 42, 47]. Emulsification also increases viscosity and will improve the distribution of the acid in layered and heterogeneous reservoirs. Acidizing foams are aqueous, in which the continuous phase is usually hydrochloric acid (carbonate reservoirs) or hydrofluoric acid (sandstone reservoirs), or a blend, together with suitable surfactants and other stabilizers [24, 56]. Foaming an acidizing fluid increases its effective viscosity, providing mobility control when it is injected [47]. 

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