8.+Annotated+Bibliography

Becker JR. 1997. Crude oil waxes, emulsions and asphaltenes. Tulsa, OK, USA: Penn Well Publishing Company.
This book identifies and addresses many problems faced by the production, transportation, and refining of waxy crude oils and associated deposits. Multiple chapters are devoted to discussing the importance of chemical and physical properties in the formation of waxes in crude oils. The limitations and effectiveness of a variety of different wax control methods are also examined and evaluated. The author points out that the treatment of wax problems in crude oil is not as simple as adding a crystal modifier to lower the aggregate interactive forces. Sometimes, the treatments could include resolving emulsions, dispersing of solids, as well as suspending asphaltenes before acceptable treatment is achieved. The author proposes and uses many plausible but hypothetical concepts to explain the structure and composition of asphaltenes, maltenes and resins, which could potentially mislead the reader. The book is published in 1997, and is one of the most recent published books on the topic. The sources consulted are all reputable and well referenced. Unlike other books on the same topic, this book contains multiple pages of illustrative chemical structures and process diagrams which aid readers in visualizing and understanding the formation of deposits. More importantly, the book is written at an introductory level suitable for readers without advanced chemical engineering background. The book is very helpful for understanding the chemistry behind paraffin wax deposition, and serves as a great introductory source for methods of removal, but more recent and detailed published papers on inhibition and prevention is recommended for a more thorough understanding.

===Bello OO, Fasean SO, Teodoriu C, Reinicke KM. 2006. An evaluation of the performance of selected wax inhibitors on paraffin deposition of Nigerian crude oils. Petroleum Science and Technology. [Cited 2010 October 31]; 24:195-206. Available from: http://www.informaworld.com/smpp/content~db=all~content=a741940557. === This article provides a comparison to various chemical solvents on paraffin inhibition and measures the amount of deposition observed. The additives used were more effective in paraffin deposition than the control, and in particular, Trichloroethylene was found to be the most effective in prevention of paraffin deposition. In addition, the article compares the rate of deposition inhibition with varying concentrations of trichloroethylene-xylene. The article concludes that a ratio of 50/50 composition (trichloroethylene-xylene) was considered as the most cost effective solution with very little significant gains in efficiency outside the ratio, which was very interesting. Evaluation with a lower additive to higher crude ratio would be a better representation of real world conditions where further refinement of chemical inhibitors of paraffin disposition would be done. The study is conducted in a controlled environment to stimulate the possible condition; therefore, field data would greatly improve the validity of the study. Regardless, it provides the groundwork for further study into the use of trichloroethylene–xylene as a paraffin inhibitor for our project because it focuses mainly on the technical aspect of inhibition and prevention and did little to explain the specific chemistry behind it. Also, a basic understanding of the chemical and physical properties of paraffins would assist in understanding the different types of control mechanisms evaluated.

===Schmidt L. 2010. CBU technical training: paraffin wax and asphaltene fundamentals and paraffin wax treatment for oil wells. Calgary, AB, Canada: Champion Technologies PowerPoint presentation. === Champion Technologies’ CBU technical training course on paraffin wax and asphaltene fundamentals, and paraffin wax treatment for oil wells is an internal document used to educate new employees on paraffin wax and asphaltene. It explains what paraffin wax and asphaltene are, the differences between them, why they are problematic in oil production, and what kinds of treatment options are available. The course is basic in its approach in explaining the mechanisms through which paraffin wax and asphaltene deposition occurs; however, what I found most useful is that it highlights the most important factors that affect paraffin wax deposition. Along with temperature, pressure, solubility, and pH of the oil, the Wax Appearance Temperature (WAT), also known as the Cloud Point, is the most important factor to consider. After we understood these fundamentals, our group could then focus our research on more technical analysis of paraffin wax deposition. One limitation I found with this source is that because it is an internal training course used by a company that specializes in chemical solutions for oil and gas production problems, its treatment options focus on the products that the company sells: their Flexoil and Flotron product lines. The material does briefly explain alternatives to their specific chemical solutions; however, because it is an internal document, the scope of the treatment solutions is slightly limited. Regardless, this source is very useful in providing the necessary information on paraffin wax and asphaltene and helped create the foundation for further research for our project.

===Muller-Steinhagen H, Malayeri MR, Watkinson AP, editors. c2009. Fouling in crude oil preheat trains: a systematic solution to an old problem. Proceedings of International Conference on Heat Exchanger Fouling and Cleaning; 2009 June 14-19; Schladming, Austria: Engineering Conferences International. === “Fouling in Crude Oil Preheat Trains: A systematic Solution to an Old Problem” provides general information about the problems of asphaltene and paraffin fouling through the mechanism of deposition in a number of industrially relevant contexts. The report, which is based on a Crude Oil Fouling (CROF) project funded by the UK Engineering and Physical Sciences Research Council (EPSRC), consists of summaries of the work done to date through a number of ‘sub-projects’ which look specifically at an area of interest related to crude oil fouling: for example, sub-project A attempts to characterize foulants. The authors of this article present the information in a clear and concise manner while maintaining a technical tone and outlook on the topics. The sub-projects, which are the focus of the article, all aim to apply an understanding of the mechanism and fundamental chemistry concepts related to fouling in crude oil to the design of better systems to deal with fouling. Numerous solutions for problems are noted, but are slightly limited because they are often based on the experiences of the authors, with little quantifiable supporting data. Still, this article provides plenty of useful information in aiding to develop the solutions component to our project because of the industrial relevance associated with this article.

===Wang KS, Wu CH, Creek JL, Shuler PJ, Tang Y. 2003. Evaluation of effects of selected wax inhibitors on paraffin deposition. Covina, CA, USA:Power, Environmental, and Energy Research Center, Division of Chemistry and Chemical Engineering, California Institute of Technology; [ January 2003; October 31, 2010]. === The article “Evaluation of Effects of Selected Wax Inhibitors on Paraffin Deposition” displays how different chemicals mixed with an n-decane/paraffin solution can inhibit the precipitation of paraffins on surfaces. The study that was conducted showed that some of the inhibitors they tested in this n-decane solution reduced paraffin deposits, in some cases, by up to 83%. However, it also mentions that these inhibitors did not do an effective job of reducing paraffins of C35 and higher, but were instrumental in reducing lower carbon count paraffins. The authors suggested that chemical alterations to the surfaces which are prone to paraffin fouling would be a good idea. The article was experimental in its nature, and calculations were done just to illustrate how effective some inhibitors were at reducing paraffin buildup. Among some of the chemical inhibitors mentioned were Polyalkyleneimine, Polyolefin amide alkeneamine, and Polyalkylacrylate. The article displayed to us that there are numerous chemical techniques to remove/decrease paraffin buildup in pipes; however, there still isn’t a “magic bullet” technique to remove all paraffins, especially heavy (C35 and above) paraffins. A stronger technical background is recommended for a thorough understanding of the concepts brought up by this article, but it will help us broaden our scope on possible paraffin fouling solutions and provides strong experimental data to support it.

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