Risk assessment of salt precipitation in Vankor field wells and selection of the optimal prevention technology

Risks of calcite scaling in submersible equipment were estimated on the basis of studies the composition of produced water and oil production conditions. There was analyzed the need of use the mutual solvent during the inhibitor squeezing procedure into the formation. Economical reasonable protection methods against scaling are proposed.
Materials and methods
The composition of produced water was studied. Experiments on filtration the inhibitors through core samples of Vankor field were conducted at the installation forcore examination. The adsorption-desorption properties of inhibitor were determined, adsorption isotherms were constructed. The influence of the mutual solvent for the restoration of the permeability coefficient was revealed.
Results
Risks of scale in the process of oil production were estimated in the course of studying the physical and chemical properties of downhole fluids of Vankor field and modeling of precipitation of sparingly soluble salts. Technologies of protection the submersible downhole equipment were offered.
Сonclusions
In article was analyzed risk of salt deposition in mixing reservoir water, produced water and artesian waters. The risk of salt deposition was established. The numbers of lab tests on scale inhibitors were carried out. The procedure of squeezing inhibitor into the formation was simulated. The positive effect of the application of the mutual solvent for the restoration ofthe permeability coefficient after squeezing inhibitor into the formation was established.