Abstract: A thermal vapor compression (TVC) based desalination system for oilfield wastewater is proposed to combat the difficulties resulted from complex and strongly polluting substances of the wastewater in using membrane methods. The complete mathematical model for process simulation and design is developed and the influences of evaporation temperature on the system performance are analyzed. The results show that the performance ratio increases as the evaporation temperature decreases, lowering evaporation temperature may significantly reduce motive steam consumption. However, lowering evaporation temperature may greatly increase the heat transfer area and the cooling water flow rate.

Key words: oilfield wastewater, desalination；thermal vapor compression；mathematical model

摘要： 针对油田污水污染物成分复杂、污染性强不适合膜法脱盐的特点和淡水消耗与余热资源共存的实际，提出用热力蒸汽压缩（TVC）蒸发技术对油田污水进行集中脱盐处理的技术方案。建立了基于TVC的油田污水脱盐系统的工艺流程设计计算模型，系统分析了蒸发温度等主要运行参数的影响。结果表明：系统性能系数随蒸发温度的降低而增大，降低蒸发温度有助于减少主蒸汽消耗，但所付出的代价是总传热面积和污水泵流量的增大；TVC系统的热力学完善度相对较低，与多效蒸发系统联合使用是改善系统性能的基本途径之一。尽管如此，对于油田生产来说，当存在合适的余热资源时，简单的单效TVC系统仍不失为合理的技术方案。

关键词: 油田污水, 脱盐, 热力蒸汽压缩, 数学模型