土壤原位燃气热脱附二次回流加热系统研究

Research on secondary reflux heating system for in-situ gas thermal desorption of soil

为考察原位热脱附技术中二次回流对土壤温度场分布的影响,寻找一种提升二次回流节能效果的策略,采用模型模拟的方式,对比不进行回流、进行二次回流、调整影响半径后进行二次回流对土壤冷点温度、烟气温度、加热井周边土壤温度平均值和标准差的影响。结果表明,进行二次回流后能量利用率提升46%,可节省35.29%的能耗,但增加了冷点达到目标加热温度的时间差。调整影响半径后进行二次回流可以显著提高冷点达到目标加热温度的一致性,设置两口加热井影响半径相差16 cm时,可节省41.18%的能耗。

To investigate the effect of secondary reflux on soil temperature field distribution of in-situ thermal desorption technology and find a strategy to enhance the energy efficiency of secondary reflux,this paper used model simulations to compare the effects of no reflux,secondary reflux and secondary reflux after adjusting the influence radius on soil cold point temperature,flue gas temperature and the mean and standard deviation of soil temperature around the heating wells.The results showed a 46%increase in energy utilization for secondary reflux and saved 35.29%of energy consumption,but increased the time difference when the cold point reached the target heating temperature.Secondary reflux after adjusting the influence radius could significantly improve the consistency of the cold point reaching the target heating temperature,and the energy saving could reach 41.18%when setting the influence radius of two heating wells with a gap of 16 cm.