RATIONALE FOR SELECTING SAND FILTERS FOR PRODUCTION WELLS

Link for citation: Khabibullin M.Ya., Khabibullin  A.M. Rationale for selecting sand filters for production wells. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 7, рр. 26-34. In Rus. The relevance of the study are caused by the need to ensure the flow of more purified reservoir fluid into the bottomhole zone of the well. When opening a formation with production wells, the design of which includes anti-sand filters, there are some imperfections that are characterized by the degree and nature of its opening and are caused by the designs of casing filters. For a rational choice of an anti-sand filter in a well, it is necessary to conduct experimental bench studies, taking into account well conditions. Purpose: based on the results of experimental studies, propose the optimal design of the anti-sand filter. To select, it is necessary to take into account the hydraulic parameters of its operation, which can be determined based on the bench tests of two types of filter elements: block and frame-rod with wire winding, in open and cased hole conditions, as the most promising in terms of application. Objects. To accomplish this task, a stand was created that allows you to: determine the amount of fluid passing through with sand; the volume and granulometric state of the sands that pass through the filters when filtering the mixed liquid; state and change in the structure of rocks in the bottomhole zone of the well; distances between the filter elements and the production casing, the performance of the sand filter. The main component of the stand is a combined-shaped filtration tray imitating a circular reservoir model. Methods. The working fluid (oil), preheated to a predetermined temperature with the help of a heating element, is supplied to the filtration tray by a pump from the receiving tank through the pressure manifold. The temperature of the working fluid in a given mode is maintained using a non-contact controller. The discharge pressure is measured with a manometer. The pressure manifold is fitted with a spring-loaded relief valve. The change in pressure of the radial flow of the working fluid in the filtration tray is recorded by a pressure sensor. The working fluid from the filtration tray is passed through a cleaning system made in the form of two cylinders, in which there are sieves for trapping and screening sand particles with a size of 0,005 mm or more. The purified working fluid again enters the receiving tank. Results. Block and single-layer wire filters while ensuring a small amount of sand are quickly clogged. The double layer wire filter has the highest peak resistances and occasional significant sand production. Obviously, it can be recommended for flowing oil production, with a significant excess of reservoir pressure in relation to hydrostatic pressure.