静压支承技术在海水淡化旋转式能量回收装置中的应用

海水淡化旋转式能量回收装置（RERD）高、低压流体间的泄漏主要在转子与端盘的配合间隙中发生,这种泄漏直接影响到装置的能量回收效率水平。本文通过在平面端盘上引入阻尼孔和静压支承槽,构建了静压支承端盘方案,将静压支承技术应用到自主开发的电驱RERD装置中,以解决其运行过程中泄漏量大、能量回收效率低等问题。在转子与上、下端盘配合总间隙为0.04mm、转子转速为500r/min的条件下,RERD分别使用平面端盘和静压支承端盘进行对比实验研究。结果表明,在操作压力为4.5MPa和处理量为13m³/h的工况下,与平面端盘相比,采用1^#静压支承端盘（静压支承槽槽宽为2.0mm）时,装置的泄漏量从0.45m³/h减小至0.28m³/h,能量回收效率从91.3%提升至92.7%。采用2^#静压支承端盘（静压支承槽槽宽为3.0mm）的RERD在相同工况下,装置的泄漏量可降低至0.11m³/h,能量回收效率提升到95.0%。上述研究显示静压支承技术对于减小RERD装置泄漏量、提高装置效率具有显著的效果,对RERD装置密封结构设计与优化具有指导意义。

Application research of hydrostatic bearing technology in rotary energy recovery device for seawater desalination system

The leakage between high and low pressure fluids in the rotary energy recovery device (RERD) for seawater desalination system, which has direct effect on the energy recovery efficiency of the RERD, mainly occurs in the mating clearances between the rotor and the end plates. This research employed the hydrostatic bearing technology into the self-developed motor-driven RERD by making the hydrostatic bearing groove and the damping hole on the flat end plate and creating the hydrostatic bearing end plates to reduce the leakage and improve the efficiency of RERD. The RERD with flat end plates and the RERD with hydrostatic bearing end plates were experimentally compared under the total mating clearance of 0.04mm and rotating speed of 500r/min. The results showed that under the testing conditions of operating pressure of 4.5MPa and capacity of 13m³/h, the leakage of the RERD with 1^# hydrostatic bearing end plates (groove width of 2.0mm) could decrease from 0.45m³/h to 0.28m³/h and the energy recovery efficiency could increase from 91.3% to 92.7% when compared with the RERD with flat end plates. The RERD with 2^# hydrostatic bearing end plates (groove width of 3.0mm) was tested under the same operating condition. The leakage was lowered to 0.11m³/h and the efficiency was improved to 95.0%. The research above indicates the significant effect of the hydrostatic bearing technology in reducing the leakage and improving the efficiency of the RERD, and has important guiding significance for the design and optimization of seal structure of the RERD.