Reverse Combustion Linking (RCL) Modelling for Underground Coal Gasification (UCG)

Liangliang (Timick) Jiang



This work shows that RCL is a very viable, effective and advantageous linking technique for UCG. It helps put UCG in a much competitive position; Caution must be taken for securing a successful RCL. Water removal is imperative to build a clear air connectivity before ignition; Limitations in reaction kinetics and heat transfer contribute to relatively constant linking speed regardless of moderate operational fluctuations. A larger channel is obtainable by using a high injection rate and/or pressure; A minimal threshold injection rate might exist for sustaining a stable combustion front. Inducing unknown fractures may not be beneficial to UCG, or even disastrous; Abounding hot char in place after RCL brings extra credits. It is advised to do forward combustion swiftly before reservoir cools down.