A Novel Shallow Well Monitoring System for CCUS: With Application to Shengli Oilfield CO2-EOR Project

摘要

The carbon dioxide (CO2) flooding to improve the recovery ration of oil reservoir (EOR) is becoming one main way of EOR in the Shengli Oilfield, Shandong province, Northeast China. As one of the largest and oldest oilfields in China, the Shengli oilfield CCUS demonstration project is a true full-chain project from capture, pipeline transportation, utilization through storage. In particular, this CCUS project implements a wide spectrum of monitoring and assessments. A novel shallow well monitoring system is developed to detect the leakage of CO2 at shallow formations. The core of this novel system is to adopt the U-tube sampling technology to accomplish collections of samples of water and gas in a convenient and cost-effective way. The shallow well is designated to a depth of 10 meters with a maximum five-block separation, i.e. it can obtain samples of water and/or gas at five different depths in maximum in a shallow well. The novel system has been tested to obtain geochemical samples of water and gas during a CO2-EOR demonstration experiment conducted in the Shengli oilfield.