Well, my dears, an ‘acid wash’ is simply a process used to clear debris from in and around an oil or gas wellbore after the drilling and installation of casing and cement has been completed.
You see, pumpkins, the hydrocarbon bearing rock can be quite clay-like in places, so it clumps in and around the wellbore along with residues of the drilling muds used to bore the hole. In turn, these impede the flow of those hydrocarbons from the rock and up into the well.
Operators mix a dilute solution of an inorganic, mineral acid at the surface – in Cuadrilla’s case at Balcombe, I see their intention is to use Hydrochloric Acid – and use this to flush out the debris in the bottom of the well.
The acidic solution, dears, reacts with the alkaline (usually calcium-based) mineral content of the rock and dissolves it.
During the reaction, the acid is neutralised and the harmless by-products calcium chloride, water and a small amount of carbon dioxide are formed.
So, you see, it’s not as bad as it sounds, cherubs, and certainly isn’t something to be afraid of.
Until next time xxx