Complex Fluid and Gas Preparation

Understanding how oil and gas are produced from reservoirs and determining how to maximize their production relies on three things: a knowledge of the rock, a knowledge of the fluid, and a knowledge of how the rock and fluid interact.

In order to meet two of these criteria, there must be an accurate knowledge of the reservoir fluids. Such knowledge can only be achieved through either the procurement of fluids directly from the reservoir or the accurate replication of reservoir fluids. Because sampling large quantities of fluids, especially gases, from a reservoir is expensive and inefficient, gases are generally mixed to the correct composition.

There are many complications associated with the preparation of reservoir fluids, making the purchase of these fluids tedious, time consuming, and expensive, none of which are conducive to the high volume of reservoir condition experiments for which the COIFPM has been designed. To keep compositions confidential and to make fluid (both gases and liquids, including live crude) preparation efficient, a gas mixing system – designed and built at the University of Wyoming – is used. The system utilizes the principles of gravimetry to very accurately mix gases and liquids based on their weights. Furthermore, its high capacity allows for several liters of fluid to be mixed at once, while its high-pressure pumps can be used to pressurize the mixtures to up to 10,000 psi. Finally, a fully customized gas chromatograph can be employed to confirm the compositions of all mixed fluids including oil, gas, and any other hydrocarbon liquids. Using proprietary hardware and software, the chromatograph can analyze reservoir fluids at reservoir conditions (i.e. elevated temperatures and pressures).

When combined with the myriad of rock characterization equipment, such as CT scanners and microscopes available at the COIFPM, the ability to prepare highly complex reservoir fluids in-house allows for the study of the rock-fluid interactions that govern fluid displacement mechanisms in reservoirs. This is ultimately leading to improvements in oil and gas production from reservoirs throughout the world.