The last 3 years have seen an unprecedented increase in paraffin-related challenges in the world of production chemistry. The industry is producing more-challenging crude oil as the production of light, sweet, and easy-to-treat crude declines. The new crudes coming on stream contain more-complex combinations of paraffinic components.
We are aware of the bimodal distribution of paraffin displayed nicely in high-temperature gas chromatography of, for example, Eagle Ford crude oil, which shows a double peak distribution of paraffin. Some of the more-recent publications highlighted are using more-advanced analytical techniques to characterize crude oil because heavier paraffin components are not detectable by classical methods. Characterization using techniques such as nuclear magnetic resonance and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry are detecting paraffin chains in excess of C100 and determining a trimodal distribution of paraffin in crude oil that is difficult to treat using today’s technology, thus requiring a change in approach and thinking for the production chemist. Such crudes are being developed today—crude oils from some of the more extreme shale plays around the world such as the Montney formation in British Colombia, Canada; Vaca Muerta in Argentina; East African crude oils of Uganda, Chad, and Kenya; and crude oils in the Far East such as those in Indonesia and Vietnam.
The current chemical technology begins to reach its limit of functionality in a crude oil that contains paraffin chains of C75+ in length. The featured papers give some insights into the work under way to elucidate the structure performance relationships between inhibitors and crude oils containing these higher paraffinic species. Much work remains in order to develop more-effective solutions and strategies for these incredibly challenging and highly paraffinic crude oils.
The featured papers summarize some of the state-of-the-art techniques to determine the true nature of paraffin deposition from these bi- and trimodal crude oils as well as advanced techniques to truly characterize and treat produced fluids and recovered solids samples. Readers are encouraged to research the recommended additional reading and take some time to delve into the references contained in these papers. This literature contains an extensive review of the history and current state of the art in paraffin science for the oilfield chemist and engineer.
This Month's Technical Papers
Reassessing Operational Strategies for Wax Management Reduces Expenses
Enhanced-Gel-Strength Concept Optimizes Chemical Use in Pipeline for Waxy Crude
Novel Polymer Modifications Lead to Next-Generation Pour-Point Depressants
Recommended Additional Reading
OTC 27855 Work Flow To Evaluate Wax-Deposition Risk Along Subsea Production Systems by O. Coronado, Genesis, et al.
OTC 28714 Cold-Finger Benchmarking Study for Paraffin-Inhibitor Selection by Yun Peng, Shell, et al.
SPE 187252 Investigating the Performance of Paraffin Inhibitors Under Different Operating Conditions by Anshul Dubey, The University of Tulsa, et al.
| Jonathan Wylde, SPE, is the head of global innovation at Clariant Oil Services based in Houston. He holds a BS degree in geology and a PhD degree in physical chemistry from the University of Bristol, UK. Wylde is the author of more than 150 papers and holds several patents. He serves on the JPT Editorial Committee and on committees for the SPE International Conference and Exhibition on Oilfield Scale, the SPE International Symposium on Oilfield Chemistry, and the SPE Annual Technical Conference and Exhibition. Wylde is also a technical editor for SPE Production & Operations and SPE Journal. He can be reached at jonathan.wylde@clariant.com. |
