Review of the Plugging Mechanisms and Plugging-Removal Technologies of Mechanical Sand-Control Screens

Mechanical sand-control screens are core completion components for maintaining sand retention and flow conductivity in oil, gas, geothermal, hydrate, and underground gas storage wells. This review summarizes recent progress in the plugging mechanisms, diagnostic indicators, and plugging-removal technologies of mechanical sand-control screens. The reviewed studies show that screen plugging is a multi-mechanism process controlled by external sand bridging, internal fines invasion, drilling/completion fluid residues, chemical scaling, organic deposition, and their coupled cementation effects. External plugging is mainly associated with slot- or pore-entrance bridging and filter-cake compaction, whereas internal plugging is controlled by fines retention in mesh layers, prepacked gravel, or tortuous porous media. Pressure drop, permeability damage/recovery, produced-sand particle-size distribution, and microstructural characterization are key indicators for evaluating plugging severity and treatment effectiveness. Hydraulic jetting, mechanical vibration, ultrasonic treatment, acidizing, oxidizing systems, thermochemical treatment, and physical–chemical combined methods are compared in terms of mechanisms and applicability. The analysis indicates that single treatments are usually insufficient for strongly cemented multicomponent plugging; a sequential strategy of chemical weakening followed by physical stripping and flowback is more suitable for complex field conditions. Future work should focus on green and selective chemical systems, downhole diagnosis-guided treatment selection, and integrated sand-control designs combining plugging prevention, monitoring, and removal.