This paper presents experimental and simulation studies to evaluate the feasibility of sequestering supercritical CO2 in depleted gas reservoirs. Experimental results were simulated to obtain gas-liquid relative permeability curves used in the field simulation study.

A 3D simulation model of one eighth of a 5-spot pattern was constructed to evaluate injection of supercritical CO2 under typical field conditions. Simulation results indicate the following. First, a large amount of CO2 in sequestered: about 1.2 million tons in 29 years (40-acre pattern), and 4.8 million tons in 56 years (80-acre pattern). Second, a significant amount of natural gas is also produced: about 1.3 BSCF or 74% OGIP (40-acre pattern), and 4.9 BSCF or 68% OGIP (80-acre pattern). Third, at $2.00/MSCF, produced gas revenue amounts to about $2.6 million to $9.8 million, which could help defray the cost of CO2 sequestration. In short, CO2 sequestration in depleted gas reservoirs appears to be a win-win technology.

Keywords:
recovery factor, sequestration, injection rate, co 2, case 1, reservoir pressure, supercritical carbon dioxide, climate change, dioxide, 40-acre pattern
Subjects:
Improved and Enhanced Recovery, Reservoir Simulation, Storage Reservoir Engineering, Environment, Chemical flooding methods, CO2 capture and sequestration, Climate change
Copyright 2003, Society of Petroleum Engineers
You can access this article if you purchase or spend a download.