水平井原位蒸汽加热土壤过程中的温度变化规律  

Temperature variation in soil during in-situ steam heating with horizontal wells

作　　者：吕静 李静文 孙于茹 赵高强 刘鹏 李书鹏 LYU Jing;LI Jingwen;SUN Yuru;ZHAO Gaoqiang;LIU Peng;LI Shupeng(Beijing Construction Engineering Group Environmental Remediation Co.,Ltd.,Beijing 100015,China;National Engineering Laboratory for Site Remediation Technologies,Beijing 100015,China)

机构地区：[1]北京建工环境修复股份有限公司,北京100015 [2]污染场地安全修复技术国家工程实验室,北京100015

出　　处：《环境工程学报》2022年第12期4085-4094,共10页Chinese Journal of Environmental Engineering

基　　金：国家重点研发计划资助项目(2018YFC1803003)。

摘　　要：应用水平井对场地内有机污染进行蒸汽强化抽提具有良好应用前景,但国内对加热半径、升温和冷却速率等关键参数的研究仍处于起步阶段。通过示范工程验证实施非开挖式水平井施工方法,研究应用水平井原位蒸汽加热土壤过程中的温度变化规律及加热影响半径。结果表明,蒸汽在注入水平井过程中,筛缝出汽量由注射井跟端到趾端逐渐减少,导致跟端土壤升温速率较趾端快。测温点距离蒸汽注射井越近,温度峰值越高;反之,温度峰值越低。假设目标加热温度为50℃,当加热至19.5 h时,水平井蒸汽加热半径达到1.8 m。停止加热后,注射井跟端土壤较趾端土壤降温幅度大。土壤初始温度越高的区域,土壤降温速率越大。经过113 h的自然冷却后,加热半径范围内土壤温度均保持在50℃以上,土壤保温效果良好。本研究结果可为应用水平井蒸汽加热修复土壤工程设计提供参考。Steam enhanced extraction with horizontal well has a good application prospect in remediation of organic pollution in site, however, the study of key parameters, such as heating diameter, heating and cooling rate are still in its infancy. Through the demonstration project, a trenchless horizontal well construction method was verified, and researched temperature variation and heating radius in soil during in-situ steam heating with horizontal wells. The results showed that, the steam output of sieve seam decreased gradually from the heel end to the toe end of injection well during the process of steam injection into the horizontal well, resulting in the soil heating rate at the heel end was faster than that at the toe end. The peak temperature was inversely correlated to the distance from the steam injection well. Assuming that the target heating temperature was 50 ℃, after 19.5 h of heating process, the steam heating radius of horizontal well reached 1.8 m. After the heating was stopped, the temperature of soil at the heel of injection well decreased more than that at the toe of injection well. The higher the initial soil temperature, the higher the soil cooling rate. After 113 h of natural cooling, the soil temperature within the heating radius was kept above 50 ℃, and the soil insulation effect was good. This study can provide reference for the engineering design of soil remediation by steam heating with horizontal well.

关 键 词：蒸汽加热 水平井 非开挖 加热半径 

分 类 号：X53[环境科学与工程—环境工程]