Petroleum prodn. by hot fluid injection from mine system - with sealed injection galleries

摘要

Recovery of petroleum (esp. viscous petroleum or bitumen) from a subterranean formation is carried out by (a) mining a system of drifts and galleries, including >=1 injection gallery and >=1 prodn. gallery; (b) drilling injection and prodn. wells into the formation from the respective galleries; (c) injecting a hot fluid (esp. steam) through the injection wells to reduce the viscosity of the petroleum and displace it towards the prodn. wells; and (d) recovering the petroleum from the prodn. wells and passing it to the surface via the prodn. gallery. The improvement comprises preventing ingress of hot fluid into the injection gallery during injection by filling the injection gallery with a sealing material. By preventing the escape of steam, the process reduces heat losses and thus reduces the consumption of steam per unit of petroleum produced.