冷循环流化床的水力动力学用于甲醇到烯酸 (MTO) 过程:实验和计算调查
Mojtaba Babaei1, Salman Movahedirad2
1School of Chemical Engineering, Iran University of Science and Technology, Tehran, Iran.
Scientific reports
|October 26, 2023
概括
这项研究检查了甲醇到烯 (MTO) 过程中的伪二维流体化床中的气体-固体流动水力学. 不对称的分离器显著改善了混合,而气泡直径受到低混合区域的限制.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 流体动力学 流体动力学
- 颗粒技术 颗粒技术
背景情况:
- 工业甲醇到烯酸 (MTO) 工艺使用循环流化床 (CFB).
- 了解气体-固体流水力学对于优化MTO反应堆性能至关重要.
- 伪二维 (2D) 冷模型提供了一种可行的方法来研究复杂的3D流动模式.
研究的目的:
- 在伪二维冷CFB中研究气体固体流的水力动力学行为.
- 评估不同波段几何形状对MTO CFB混合特性的影响.
- 分析气泡对流化床内的气体固体混合物的影响.
主要方法:
- 使用粒子图像速度测量与数字图像分析 (PIV-DIA) 来测量固体速度的实验调查.
- 使用OpenFOAM中的twoPhaseEulerFoam解决器进行水力动力学的数值模拟.
- 与实验数据对固体粒子速度和固体体积分数的数值解析器的验证.
- 探索对称和不对称的阻隔器配置.
主要成果:
- 为这项研究进行调整的OpenFOAM解决器与实验PIV-DIA数据有很好的一致性.
- 发现不对称的分离器显著增强了气体固体流的混合行为.
- 观察到气泡直径受到床内的低混合区域的限制.
结论:
- 伪2D冷CFB模型有效地模仿了工业MTO床的水力动力学.
- 不对称的分离器是提高MTO CFB混合效率的关键设计元素.
- 气泡特性与流化床的混合状态密切相关.
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