低压损管式动态旋流分离器分离性能数值模拟研究  

Numerical simulation for separating properties of low pressure-drop tubular dynamic centrifugal separator

作　　者：潘亿勇 张健[2,3] PAN Yiyong;ZHANG Jian(Exploration and Development Department of CNOOC Limited,Beijing 100010,China;State Key Laboratory of Offshore Oil Exploitation,Beijing 100028,China;CNOOC Research Institute Ltd.,Beijing 100028,China)

机构地区：[1]中国海洋石油有限公司勘探开发部,北京100010 [2]海洋石油高效开发国家重点实验室,北京100028 [3]中海油研究总院有限责任公司,北京100028

出　　处：《中国海上油气》2023年第2期212-219,共8页China Offshore Oil and Gas

基　　金：国家自然科学基金企业创新发展联合基金重点支持项目“面向海上聚驱采出水的油滴-微泡团聚机理及其协同动态旋流预除油特性研究(编号:U20B2030)”部分研究成果。

摘　　要：为降低分离过程中压力损失,减少动态旋流分离器的能耗,从旋流和泵送相结合的理念出发,提出了一种低压损管式动态旋流分离器,并构建了低压损起旋叶栅设计模型。采用计算流体动力学数值模拟方法,探讨了不同转速下同向收油和逆向收油型低压损管式动态旋流分离器的分离性能,发现较同向收油型低压损管式动态旋流分离器,逆向收油型可及时排出汇聚在叶栅出口处的高浓度油相,当叶栅转速高于800 r/min时分离效率更高。进一步分析了含油浓度、入口流量等操作参数及分散相密度和分散相粒径等物性参数对逆向收油型低压损管式动态旋流分离器分离效率的影响,结果表明:对于分散油相密度为871 mg/m3、粒径为158μm的含油污水,保持叶栅转速不变(1400 r/min),当入口流体含油浓度小于200000 mg/L、流量小于设计流量的1.8倍时,其分离效率稳定在95.5%以上,当入口流体含油浓度大于200000 mg/L或流量大于设计流量的1.8倍时,随含油浓度和流量的增加,分离效率迅速降低;分散相密度增加、粒径减小,低压损管式动态旋流分离器分离效率均逐渐降低。在此基础上,提出了可分离无量纲数(Se)的概念,并用之定量分析了低压损管式动态旋流分离器在高分离效率下,分散油相密度、油滴粒径以及叶栅转速3个重要参数的耦合关系;通过将其与已有文献实验数据所推算的最佳分离区间进行对比,间接验证了数值模拟结果的可靠性。本研究成果为低压损管式动态旋流分离器的研发提供了参考。In order to reduce the pressure loss and energy consumption of the dynamic centrifugal separator,a low pressure-drop tubular dynamic centrifugal separator(TDCS)is designed based on the idea of combination of swirling and pumping,and a low pressure-drop swirler vane design model is established.The separating properties of TDCS with downstream and overflow oil outlet under different vane rotating speeds were studied by computational fluid dynamics(CFD)numerical simulation method.It is found that the overflow oil outlet type TDCS has better separating performance when the vane rotary speed is higher than 800 r/min than the downstream oil outlet type TDCS,which can discharge the highly concentrated oil gathered at the outlet of vane immediately.The effects of different operating parameters(concentration of oil,feed flow)and different physical property parameters(density and particle size of dispersed phase)on the separating efficiency of overflow oil outlet type TDCS are further discussed.It is shown that under the condition that the vane rotary speed is 1400 r/min,dispersed phase density is 871 mg/m3,and dispersed phase particle size is 158μm,the separating efficiency stabilizes at 95.5%when inlet oil-cut is less than 200000 mg/L or and the feed flow is less than 1.8 times of design rated flow,and rapidly decreases with inlet oil-cut and feed flow increase when the inlet oil-cut is higher than 200000 mg/L or the feed flow higher than 1.8 times of design rated flow.The separating efficiency decreases with the increase of dispersed phase density or the decrease of particle size.On this basis,the dimensionless separability number(Se)is defined.The Se is used to quantitatively analyze the coupling relationships of the three key parameters of dispersed oil phase density,oil droplet size and vane rotating speed when the TDCS has high separation efficiency.By comparing the Se with the optimal separation range calculated with the experimental data available in the existing literature,the simulation results in this paper ar

关 键 词：油水分离 低压损管式动态旋流分离器 收油方式 操作参数 物性参数 可分离无量纲数 

分 类 号：TQ028.4[化学工程]