Lessons from an Historic Cold-Snap
March 04, 2021
It has been a little over 30 years since we had a cold snap of this level, and we have learned a little more about how to perfect our approach to these rare occasions. We found some opportunities to improve and will address to keep our customers and ourselves running for the next time.
Every winter, we work with Power Service to develop our treatment plan and discuss the temperature range to treat and double-treating the fuel when it gets frigid.
We also offer our customers the option to blend their fuel with #1 diesel, which does not contain wax but comes at a higher cost and requires a bit more planning as it isn’t possible to blend when tanks are already full, and it doesn’t remove the wax that has already settled at the base. Additives cannot be used at the time of need in these sub-zero environments as the concentrate will not dilute properly in a fuel that is 35ºF or less.
Treating fuel is a quicker response and has saved a customer significantly without paying and using blended fuels during times of warmer temperatures.
The formulation of #2 diesel fuel has changed over the years, but the one constant is wax settling in cold environments. This process is called “cold soak.” It happens when the tank or machine doesn’t move for an extended period or get agitated. The temperature falls below 17-19 degrees Fahrenheit, and the wax falls out of suspension and accumulates in the base of the tank – where your pickup tube is.
Fuel filters, of course, will prevent this wax from traveling around your fuel system. Often referred to as gelling, it can limit fuel flow to the point that the trucks or equipment will not start, much less run. Replacing the filter without curing the source will likely get you started but won’t get you down the road very far before the new filter clogs up.
Another type of gelling is from the Glycerin in Biodiesel. This gel version does not go back to a liquid, and a common situation saver from Power Service, 911, will not clear this up.
We were not free from issues ourselves that frigid, sub-zero degree Monday morning – we had two trucks frozen up even though the block heaters were plugged in. It turns out, the outlet we plugged them into was not working, so that is easy to solve. Two other trucks had faulty block heaters. Again, easy to fix. The critical point to recognize is that none of our fleet had any fuel gelling or freeze issues after sitting for the weekend.
CCO did have some customers suffer from starting and running issues as well as fuel pumping problems:
Customer 1:
Fuel Program: Double treated with Power Service before the cold snap
Issue: Can’t pump fuel from the tank
Discovery: Cold soak, contamination, and frozen water in the tank
Resolution: Replumb tank pickup higher in the column to avoid pulling wax from the base of the tank in cold weather
Customer 2:
Fuel Program: Single treated with Power Service before the cold snap
Issue: Can’t pump from the storage tank
Discovery: Cold soak
Resolution: Pulled out treated fuel and replaced with Diesel #1
Customer 3:
Fuel program: Double treated with Power Service before the cold snap
Issue: Can’t pump from the storage tank
Discovery: Cold soak, contamination in the tank, frozen water in the tank, 10-micron filter
Resolution: Replumb tank pickup higher in the column to avoid pulling wax from the tank base in cold weather and change the filter to 30 micron, clean tank, and remove water.
Customer 4:
Fuel program: Single treated with Power Service before the cold snap
Issue: Can’t pump from the vertical storage tank
Discovery: Cold soak, 10-micron filter
Resolution: Replace filter with 30 micron, recommended annual tank inspection for water and contaminates.
Customer 5:
Fuel program: Blended 60/40 before the cold snap
Issue: Can’t pump from the storage tank
Discovery: Cold soak
Resolution: Wax Anti-Settling Additive (WASA), fill fleet at CCO Cardlock.
Analysis
This “100-year” cold snap introduced lower than average temperatures that tested the systems in place and presented similar issues across the board. Single/double treated or blended fuels had identical problems with cold soak in the frigid temperatures. Wax in diesel fuel falling out of suspension to the tank base where the pump pickup tube feeds has proven to deliver a very high wax content that rapidly clogs filters. It should be noted that CCO did not have any operability issues, just fuel delivery issues that caused us to find solutions for future conditions when they happen.
Opportunity
Tank maintenance is an issue that we have been relaying to our customers, and this event has reinforced the need for storage tanks that are regularly checked for water, dirt, and debris. These contaminants are introduced over time and are not easily stopped in an active-use environment. Our trusted partnership with ReNuel has shown a tremendous record of quality work, and we are happy to assist in getting them to your location or even an annual check-up.
Additionally, we are investigating and testing a Wax Anti-Settling Agent (WASA) to keep the wax suspended longer into a hard freeze as we had. The WASA additive will be tested in a laboratory environment to find when the right time and what amount is necessary for the desired results.