Analysis of Crude Oil Desanding Methods and Optimization of Experimental Methodologies

To address the widespread challenge of sand production during crude oil extraction in oil wells, this study systematically evaluates and compares mainstream desanding technologies utilized domestically and internationally, including gravitational sedimentation, centrifugal separation, and filtration separation. The findings indicate that gravitational sedimentation, characterized by its low cost and suitability for continuous production, demonstrates limited efficacy in removing fine particles smaller than $50 \mu \mathrm{~m}$. Centrifugal separation enhances the solid-liquid density difference, achieving a sand removal rate exceeding $90 \%$ in low-viscosity crude oil ($\lt 100 \mathrm{mPa} \cdot \mathrm{s}$), but encounters significant limitations in high-viscosity applications ($\gt 500 \mathrm{mPa} \cdot \mathrm{s}$). Filtration separation depends heavily on the performance of filtering media, resulting in high operational costs and challenges in meeting continuous operational requirements due to frequent maintenance needs. Experimental investigations into heavy oil containing silt and sand-employing methods such as sedimentation, centrifugation, electric dehydration, and ultrasonic treatmentrevealed that heated gravitational sedimentation achieved a desanding rate exceeding 95%. However, it remained ineffective for particles smaller than $20 \mu \mathrm{~m}$. Electric dehydration and ultrasonic methods demonstrated moderate overall performance, with sand removal rates of approximately $80 \%$. While existing technologies are well-established for field applications, they fail to meet the stringent precision requirements of laboratory environments for fine particle separation, particularly for particles smaller than $20 \mu \mathrm{~m}$. This necessitates the development of next-generation desanding technologies tailored to laboratory settings to enhance the accuracy of crude oil property data. This research provides robust theoretical and experimental foundations for optimizing current desanding techniques and advancing novel methodologies aimed at improving both industrial efficiency and analytical precision.