In the industrial process of producing the strong phosphoric acid(SPA),clarification of the solution is essential to the ultimate product.However,the large viscosity of sediment and the induced interface interaction r...In the industrial process of producing the strong phosphoric acid(SPA),clarification of the solution is essential to the ultimate product.However,the large viscosity of sediment and the induced interface interaction result in difficulties when the SPA is clarified.CFD numerical methodology was applied to simulate internal flow field and performance of the low speed scraper based on Mixture solidliquid two-phase flow model.Sediment deposition was generated by loading solid particles at the bottom of clarifying vessel.The moving mesh and RNG k-εmodel were used to simulate the rotational turbulent flow in clarifying tank.Variables studied,amongst others,were the scraper rotation speed and the mounting height,which could affect the solid suspension height.Features of flow field and solid volume fraction distribution in computational domain were presented and analyzed.The numerical reports of the scraper torque and velocities of inlet and outlet filed were obtained.It seems the torque value of rotatio-nal axis and particle suspending height augment with an increasing rotating speed.Meanwhile,a high revolving speed is good for the deposition discharge.The particle fraction distribution in meridional surface and horizontal surface at fixed rotation speed were analyzed to determine the corresponding optimal installation height.The simulating results reflect the flow field is marginally stirred by the scraper and proper working parameters are obtained,in which case the comprehensive properties of the scraper and the clarifying tank are superior.展开更多
【目的】鄂尔多斯盆地东缘大宁−吉县区块深部煤层气已实现规模开发,投产水平井近150口,在生产过程中发现随着地层能量逐渐降低,气井携液能力下降,井筒积液成为影响深部煤层气井产量的主要因素之一。深部煤层气游离气和解吸气共同产出,...【目的】鄂尔多斯盆地东缘大宁−吉县区块深部煤层气已实现规模开发,投产水平井近150口,在生产过程中发现随着地层能量逐渐降低,气井携液能力下降,井筒积液成为影响深部煤层气井产量的主要因素之一。深部煤层气游离气和解吸气共同产出,气液比变化大,且不同阶段产气通道及排采工艺不同,适合深部煤层气水平井生产特征的积液诊断预测方法亟需建立,为积液防治提供依据,避免因积液造成储层伤害和产能影响。【方法和结果】基于不可压缩黏性流体的RANSκ-ε方程与volume of fluid method(VOF)方法,利用流体动力学软件Fluent及其二次开发功能,结合深部煤层气水平井油管、环空气液两相流物模实验,构建深部煤层气水平井气液两相流动数值模型,通过数值模拟结果建立适合于深部煤层气水平井不同井筒压力、不同井斜角、圆管条件下和环空条件下的流型图版。基于生产过程中气液两相流动规律及流型演化过程,建立流型与积液的对应关系,得出:泡状流、段塞流对应已发生积液状态,搅混流对应即将发生积液的过渡状态,环状流对应无积液或积液风险较低状态,并且井斜角大小与积液风险成正比,压力与积液风险成反比。【结论】利用积液诊断的流型图版分析法,应用于大宁−吉县区块深部煤层气水平井,指导提出干预时机,及时采取治理措施,措施有效率提高。下一步将引入人工智能技术,向智能分析预测方向进一步优化此方法,为深部煤层气井筒积液预测和防治提供技术支撑。展开更多
基金Graduate Research and Innovation Program in Jiangsu Province(KYZZ16_0286)
文摘In the industrial process of producing the strong phosphoric acid(SPA),clarification of the solution is essential to the ultimate product.However,the large viscosity of sediment and the induced interface interaction result in difficulties when the SPA is clarified.CFD numerical methodology was applied to simulate internal flow field and performance of the low speed scraper based on Mixture solidliquid two-phase flow model.Sediment deposition was generated by loading solid particles at the bottom of clarifying vessel.The moving mesh and RNG k-εmodel were used to simulate the rotational turbulent flow in clarifying tank.Variables studied,amongst others,were the scraper rotation speed and the mounting height,which could affect the solid suspension height.Features of flow field and solid volume fraction distribution in computational domain were presented and analyzed.The numerical reports of the scraper torque and velocities of inlet and outlet filed were obtained.It seems the torque value of rotatio-nal axis and particle suspending height augment with an increasing rotating speed.Meanwhile,a high revolving speed is good for the deposition discharge.The particle fraction distribution in meridional surface and horizontal surface at fixed rotation speed were analyzed to determine the corresponding optimal installation height.The simulating results reflect the flow field is marginally stirred by the scraper and proper working parameters are obtained,in which case the comprehensive properties of the scraper and the clarifying tank are superior.
文摘【目的】鄂尔多斯盆地东缘大宁−吉县区块深部煤层气已实现规模开发,投产水平井近150口,在生产过程中发现随着地层能量逐渐降低,气井携液能力下降,井筒积液成为影响深部煤层气井产量的主要因素之一。深部煤层气游离气和解吸气共同产出,气液比变化大,且不同阶段产气通道及排采工艺不同,适合深部煤层气水平井生产特征的积液诊断预测方法亟需建立,为积液防治提供依据,避免因积液造成储层伤害和产能影响。【方法和结果】基于不可压缩黏性流体的RANSκ-ε方程与volume of fluid method(VOF)方法,利用流体动力学软件Fluent及其二次开发功能,结合深部煤层气水平井油管、环空气液两相流物模实验,构建深部煤层气水平井气液两相流动数值模型,通过数值模拟结果建立适合于深部煤层气水平井不同井筒压力、不同井斜角、圆管条件下和环空条件下的流型图版。基于生产过程中气液两相流动规律及流型演化过程,建立流型与积液的对应关系,得出:泡状流、段塞流对应已发生积液状态,搅混流对应即将发生积液的过渡状态,环状流对应无积液或积液风险较低状态,并且井斜角大小与积液风险成正比,压力与积液风险成反比。【结论】利用积液诊断的流型图版分析法,应用于大宁−吉县区块深部煤层气水平井,指导提出干预时机,及时采取治理措施,措施有效率提高。下一步将引入人工智能技术,向智能分析预测方向进一步优化此方法,为深部煤层气井筒积液预测和防治提供技术支撑。
