Reservoir Engineering

Trying to optimize the performance of existing wells, or planning for future developments?  Thimm engineering offers specialized consulting in reservoir engineering to improve the performance of your SAGD wells.

Prediction of Gas/Oil Ratio (GOR) and Produced Gas Composition

Knowledge of produced gas composition and GOR is important in commercial SAGD projects for cost effective design and operation of facilities. It is also important to understand the origin and fate of gases in the steam zone for proper understanding of pressure behaviour in the reservoir.

Thimm Engineering is the original developer of the theory of gas behaviour in SAGD, see: A General Theory of Gas Production in SAGD Operations

A number of scenarios have been successfully evaluated for clients using Thimm Engineering’s Prediction of GOR and Produced Gas Composition proprietary methods, including the following:

• Gas injection into the SAGD chamber for enhanced recovery
• Gas cap re-pressurisation, see: Gas Over Bitumen Issues
• Hydrogen sulphide generation and production, see: Improve the Accuracy of Hydrogen Sulphide (H2S) Measurements in SAGD
• Steam zone blowdown with optimization of SOR reduction
• Flue gas injection for improved recovery or green house gas sequestration, see: Carbon Dioxide and Green House Gas (GHG) Management
• Air injection for estimating the threat of excessive oxygen production in facilities
• Effects of temperature and pressure regime over time in SAGD.

To learn more, contact Thimm Engineering or view the following PowerPoint presentation:

Recent Developments in Understanding Gas Behaviour in SAGD Projects (420 KB PowerPoint ppt file)

Gas Over Bitumen Issues

Has your delineation drilling revealed significant gas reserves over your bitumen deposit? Or do you have low native reservoir pressure in zone targeted for SAGD recovery?

Thimm Engineering provided technical contributions and expert testimony for the bitumen producers in the recent Gas over Bitumen inquiry and hearings, which resulted in the Alberta Energy & Utilities Board’s (EUB) unprecedented shut in order of significant gas production in Athabasca region.

Thimm Engineering has expertise in the following areas related to Gas over Bitumen:

• Potential for gas cap souring if bitumen is preferentially produced over the gas
• Development of production forecasts of non-hydrocarbon gases proposed for re-pressurization of depleted gas caps,
• Optimal gases for possible re-pressurization of depleted gas caps, and
• Water compatibility studies.

Case Study: Conoco Surmont

In May 2000, the EUB ordered the shut-in of 146 gas wells on or next to ConocoPhillips Canada’s bitumen leases, which have recoverable reserves of five to ten billion barrels of bituminous oil sands...read more

Case Study: Leismer-Chard

The Alberta Energy and Utilities Board (EUB/Board) has made decisions on 27 applications filed by various companies that involve the production or shut-in of gas in the Chard area and Leismer Field.

Carbon Dioxide and Green House Gas (GHG) Management

The potential for CO₂ sequestration in SAGD reservoir for the purpose of Green House Gas Management has received much attention from the producers of heavy oil. With the pending implementation of CO₂ emission penalties under the Kyoto protocol, the potential to sequester CO₂ production in a SAGD reservoir could offer substantial cost advantages.

Thimm Engineering’s theoretical developments have shown that it is possible to find operating procedures that will result in a net sequestration of CO₂ and potentially improve the productivity of SAGD wells.

To learn more, contact Thimm Engineering