Format: MP3 Audio Download or Compact Disc
Presenter: Greg Malarkey
Today, we are seeing a shift in the asphalt markets due to two major trends.? First is the shift in the type of oil being produced in the U.S. (Shale or "tight") oil, which is mostly very light oil compared to the traditional production (which is a heavy type of oil).? The lighter oils when refined produce very little asphalt.? Second, much of the U.S. Refining capacity was built to run the historically available heavy oils.? To refine the lighter oils efficiently it is requiring US refiners to alter their refineries.? For example, refineries on the Gulf Coast are reported to be expending in excess of $5 billion dollars (2013-2016) to change their refineries to allow them to refine more of the lighter oil we see today.? These two events will result in less asphalts and alters the asphalts from traditional/historic types of asphalt products.? As a side note, these two things are at the core of why many roofing contractor perceive that asphalt used in shingle are changing (they are, by the way) and this portion of the presentation will help explain these observations. In the world of asphalt, about 15% of the asphalt produced in the U.S. is suitable for oxidizing.? Oxidized asphalt is the "traditional" asphalt used in making shingles. Efforts are underway on a number of fronts to address this issue.? For example, some are using/adding acid to alter the blowing dynamics asphalts for the oxidation process.? Others are blending caring types of asphalts either before the oxidation process or blending after the oxidation process. Another process to alter the available asphalts is by using polymers to "modify" the asphalts for use in making roofing. The addition of acids to traditional "blowing" and polymer modification allow shingles to be made from asphalts that are traditionally used in the paving which have not been suitable for use in shingle production. The outcome of these two processes (oxidation and polymer modification) for generating base asphalt for use in shingle also creates markedly different products which have very different performance both in the manufacturing process and in their physical attributes and the performance? of the end products. The talk would explore the changing asphalt supply, a base outline of the differences between the two processes and the differences in the product's performance. Roofing contractors are now seeing polymer modified shingles (of one sort or another) from six of the nine asphalt shingle producers (Atlas, BP,? Certainteed, GAF, IKO and Malarkey).?? These products are now offered in just about every region of North America.? Further, polymer modified asphalts are used by most manufacturers for the laminating adhesive and seal down.? This course is presented at a beginner level and is applicable in both steep and low slope asphalt roofing.
Learning Objectives:
1.?Discuss asphalts and how they are produced by the petroleum refining process.
2.?Evaluate the oxidation and polymer modification processes and how these processes produce usable asphalts for the roofing industry.
3.?Discuss the impacts of these processes on finished product's performance.
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