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An interview with Dr. Werner Reimann

  1. refining indiaCan you give a brief introduction, in your own words, what CFIs are and why they are important?
    • Sure, Cold Flow Improvers, or CFIs, are used as additives for diesel fuel to make it usable in winter. When crude oil is distilled into diesel fuel, the fuel contains dissolved paraffin waxes that crystallize when temperatures drop. The crystallization creates a gel that gets stuck in fuel filters, preventing pumping. The clogging causes the vehicle’s engine to stall, making further functioning impossible. CFIs help prevent this clogging from happening by keeping the paraffin crystals that form very small, allowing the diesel fuel to pass through the fuel filter screens and the engine to continue to run.
  2. Thanks for the simplified introduction. How long have you been working with CFIs and what is your experience with this chemistry?
    • Well, I received a one-year post-doc grant from State University of New York at Albany (SUNYA) and then began my career at Hoechst Company in Germany in polymer research. That was in 1987. I was eventually promoted to head of flow improver research with a focus on oil-soluble ethylene vinyl acetate waxes for diesel cold flow treatment. This was an exciting time because this chemistry was new at Hoechst. We just had 3 Products to sell. However, R&D continued and now we have the luxury of more than 20 individual polymers to select from. This broad selection allows us to make various tailored blends to offer the best performing additive that meets the customers needs.
  3. That’s interesting. With so many possible polymer mixtures, have you come across any particularly noteworthy situations in your career with CFIs?
    • There are many remarkable situations. I would say the most remarkable is the invention of a new chemical that allowed us to treat the diesel fuels, which were once untreatable, and bring them to specification. Other notable situations have been understanding how to design similar molecules accordingly as well as the encounter with customers that really respect and appreciate your expertise to help solve their individual cold flow challenges.
  4. I was not aware that diesel fuel alone is so complex! Recently, you wrote a paper discussing CFIs, explain a little more about your discovery.
    • My paper was about cold flow additive technology and the specific challenges in different areas around the globe. The US is quite different than the rest of the world. In the US, refineries only produce diesel fuel that meet pipeline specifications to achieve a certain pour point so that the diesel fuel does not solidify while in the pipeline. Once the fuel arrives at the terminals, cold flow additives are added to the fuel, so the consumer is pumping diesel into their tanks that meet the cold flow requirements of the local market. Also, within the US, CFI additivation is done with more flexibility compared to other areas on the globe. Terminals can adjust the additive treatment to deliver the required cold flow performance for the expected weather conditions.  My paper pointed out that Clariant’s advanced cold flow improver technology plays an important role because our chemistry copes better with the specific requirement at terminals.
  5. Thank you for that explanation. You said that CFIs are used after they arrive to the terminal, how are CFIs used in terminals?
    • CFIs used at terminals are exposed to ambient temperatures unlike in refineries where the tanks are usually heated, and diesel fuel temperature is elevated because of process heat. In the mid-west US, the weather can get really cold, and temperatures in terminals can drop to below -22°F. At this temperature, cold flow additives help fuel stay a liquid and are able to be pumped through the system. These extreme temperatures are why Clariant developed the unique terpolymer technology with outstanding low-temperature handling and dissolving properties that withstand these extreme climate conditions. Clariant also combines this product with another series of additives, called Wax Anti-Settling Additives (WASA), to further enhance the cold flow properties of diesel fuel to improve vehicle operability and avoid wax settling in bulk diesel storage tanks.
  6. It sounds like CFIs are pretty important. One last question: I was wondering, what would a world look like without CFIs?
    • Well, miserable might not be the right word, however, without additives, the only option to keep winter diesel at the required specification and keep the engine running would be undercutting (raising gas oil cut points) and Kerosene dilution. Such a scenario would cause a major part of the crude oil slates unavailable for the diesel blending, and waste a valuable resource.