Numerical simulations on the separation performance of two-stage mini hydrocyclones connected in series

• Published in: Separation science and technology Vol. 60; no. 6; pp. 737 - 748
• Main Authors: Gao, Yang, Jia, Deli, Zhao, Xiaojie, Liu, Lin, Jin, Xu, Yang, Qinghai, Yu, Jiaqing, Lin, Zisha
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 13.04.2025; Taylor & Francis Ltd
• Subjects: Adaptability; Droplets; Efficiency; fine oil droplet; Fluids; Hydrocyclones; Inlets (waterways); Mini hydrocyclone; Moisture content; Oil water separation; Oils & fats; Separation; separation efficiency; two-stage series; Water; Water content
• ISSN: 0149-6395; 1520-5754
• DOI: 10.1080/01496395.2025.2453885

Conventional hydrocyclones (CHCs) exhibit limited effectiveness in separating fine oil droplets from produced fluids, constraining overall oil-water separation efficiency. Mini hydrocyclones (MHCs) with smaller main diameter can further enhance the separation efficiency of fine oil droplets. This study constructs a two-stage series separation system using two individual MHCs. Simulations were conducted to investigate the effects of split ratio, water content, and oil droplet size on the separation performance. The adaptability of the series system to these parameters was thereby obtained. Results indicate the optimal separation efficiency is achieved when the total split ratio of the series system is 48%. The two-stage series system has better adaptability to the water content, and the separation efficiency keeps more than 97% when the water content is 86-98%, while the separation efficiency is lower than 92% when the water content is 86% in a single-stage MHC. When the inlet oil concentration exceeds 10%, for oil droplet sizes less than 0.15 mm, the two-stage series system outperforms single-stage MHCs operating independently.