Downhole steam secondary electric heating pipe column and heating method

The invention discloses an underground steam secondary electric heating tubular column and a heating method, and relates to the field of oil and gas field steam injection heavy oil exploitation. A continuous oil pipe and an electric heater are arranged in a steam wellhead, and the electric heater at the bottom end performs secondary heating on low-dryness steam at the bottom of the well, so that the temperature and pressure of the steam at the bottom of the well are increased, and the dryness is greatly improved; and high-temperature and high-pressure diffusion of steam is facilitated, the steam sweep effect is improved, then the operation effects of steam huff and puff, steam drive and SAGD are improved, and the dryness index can be improved by 20-30%. 本发明公开了一种井下蒸汽二次电加热管柱及加热方法，涉及油气田注汽开采稠油领域，通过蒸汽井口下入连续油管和电加热器，底端电加热器对井底的低干度蒸汽进行二次加热，使井底的蒸汽温度、压力升高，干度得到大幅度提升，有利于蒸汽的高温高压扩散，提高蒸汽波及效果，进而提高蒸汽吞吐、蒸汽驱、SAGD的作业效果，干度指标可以提高20-30％。