Asphaltene & Wax Flow Assurance Diagnostic Study (DFAAW)

Objective:

To determine very quickly and inexpensively the possibility and severity of asphaltene and/or wax deposition problems occurring during oil & gas production. The DFAAW study simply determines at low cost if asphaltene and wax issues should be expected in the development of a project and how severe they will be. It is absolutely necessary information for the conceptual design and sanctioning of any oil and gas project. Although hydrate problems can occur in most cases where gas and water is in contact during production and should be taken into account in facility design, asphaltene and wax problems do not always occur and, in fact, their occurrence and severity is primarily dependent on the composition and behavior of the produced fluid.

Recommended FA Diagnostic Asphaltene & Wax Tests:

For economical diagnosis of the wax/asphaltene problem, a slew of basic tests on high quality stock tank oil from every producing formation are recommended. High quality STO is obtained from flashing high quality bottome-hole samples and/or surface samples obtained with field sampling Isokinetic-Type procedures provided by AsphWax. The recommended tests are:

• Restore Oil
• API Gravity
• Asphaltene Analysis
• Wax Analysis
• Resin Analysis
• Onset of asphaltene flocculation test
• Onset of wax crystallization test (i.e., Cloud Point)
• Pour point test
• Wax melting point
• Wax solubility test at lowest field temperature
• Viscosity test and correlation

The results from the above tests help guide the analysis and interpretation of the available reservoir and production data to allow a more accurate diagnosis of any expected organic deposition problems. More importantly, the above tests provide enough information to decide whether a complete laboratory testing and simulation study is warranted. Furthermore, the above data are used in conjunction with a PVT study and PARA oil analysis (Paraffin-Aromatic-Resin-Asphaltene) to develop an EOS type fluid characterization that will permit simulating the reservoir fluid Asphaltene and/or Wax Deposition Envelope.

It should be noted that the above-recommended program is a precursor to very expensive testing with live oils. The DFAAW study helps determine the need for such expensive tests and in the process may save hundreds of thousands of dollars for operators. Occasionally, additional work with live reservoir oils may be necessary to complete the diagnosis and carry out the required simulations.