Oil and gas field chemicals

A process for increasing the effectiveness of production chemicals by reducing the number of squeezing and shut-in operations needed to increase the production rate from an oil well, said process comprising injecting into an oil-bearing rock formation a water-miscible formulation comprising:

• (a) a water-miscible surfactant which is a by-product stream from glycol ether manufacturing processes which stream contains a high proportion of n-butyltriglycol ether and (b) at least one water-miscible oil field or gas field production chemical, said components of the formulation being introduced either as a preformed single composition, or simultaneously in parallel or sequentially in either order into the rock formation.

A process for increasing the effectiveness of production chemicals by reducing the number of squeezing and shut-in operations needed to increase the production rate from an oil well by inhibiting scale formation in said well, said process comprising injecting into an oil-bearing rock formation a water miscible formulation comprising:

• (a) a water miscible surfactant which is an alkyltriglycol ether and (b) at least one water-miscible oil field or gas field production chemical scale inhibitor comprising an aliphatic phosphonic acid with 2-50 carbon atoms or an aminoalkyl phosphonic acid scale inhibitor, each bearing at least one methylene phosphonic acid group, said components of the formulation being introduced either as a preformed single composition, or simultaneously in parallel or sequentially in either order into the rock formation.

A process for increasing the effectiveness of production chemicals by reducing the number of squeezing and shut-in operations needed to increase the production rate from an oil well, said process comprising injecting into an oil bearing rock formation a water-miscible formulation comprising:

• (a) a water miscible surfactant alkyltriglycol ether, and (b) at least one water-miscible scale inhibitor comprising a monomer, oligomer or polymer having at least one hydroxyl group and/or amino nitrogen atom, said components of the formulation being introduced either as a preformed single composition or simultaneously in parallel or sequentially in either order into the rock formation.

A process for increasing the effectiveness of production chemicals by reducing the number of squeezing and shut-in operations needed to increase the production rate from an oil well, said process comprising injecting into an oil-bearing rock formation a water-miscible formulation comprising as components:

• (a) a water miscible oil field or gas field scale inhibitor composition comprising a polycarboxylic acid selected from the group consisting of lactic acid, tartaric acid and poly(meth)acrylic acid, said components of the formulation being introduced either as a preformed single composition, or simultaneously in parallel or sequentially in either order into the rock formation.