METHOD OF DETERMINATION OF DEPOSIT VOLUME IN WELL FLOW COLUMN Russian patent published in 2017 - IPC E21B47/03 E21B47/07 

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to borehole production of asphaltene oil using deep electric submersible pumps (ESPs), particularly to methods for assessing the deposit volume in the flow column. The method for determination the volume of deposit in the well flow column consists in change of the properties of the fluid entering the flow column of the well and measuring the liquid volume. In this method the frequency of the electric current of the submersible motor of the of the electric submersible pump is changed while a constant flow rate of the well fluid in the flow column, and as a result, the fluid temperature in the flow column is changed. The time of arrival at the wellhead through the flow column of the modified temperature liquid is fixed by means of two temperature sensors, one of which is located at the bottom of the flow column, while the second one - is at the wellhead. The volume of fluid with changed temperature in the flow column are the product of the required time for well fluid flow rate, and the volume of deposits is determined using the length of the tubing column between two temperature sensors, the inner diameter of clean tubing, the empirical coefficient that takes into account the difference in condition of the well production in the flow column and in the device for measuring the internal volume of the tubing, the performance of the electric submersible pump, the time of change of temperature of downhole product in the zone of temperature sensors installed in the bottom and the top of the flow column. For wells with greater length of tubing the inner surface is coated with insulating material.

EFFECT: invention extends trouble-free and efficient operation of flow column due to the identification of volume of deposit in the form of adhesive on the inner surface of the tubing with the ESP wells without lifting the tubing to the surface.

2 cl, 1 dwg