058 - Back to School - Diesel Gelling Temps

In this Fuel Pulse Show podcast episode, host Erik Bjornstad delves deeper into the complexities of diesel fuel gelling. Building on previous discussions about cloud point and cold filter plug point temperatures, Bjornstad explains how temperature patterns, not just absolute temperatures, affect fuel gelling.

He presents four common temperature scenarios and their impacts on diesel fuel, highlighting the importance of sustained cold periods and sudden temperature drops. The episode emphasizes that while typical cloud points for diesel fuels are around 16-17°F, individual fuel compositions and temperature change rates play crucial roles in gelling behavior. Bjornstad concludes by previewing the next episode on prevention strategies.

What You'll Learn:

• How temperature patterns affect diesel fuel gelling
• The impact of sustained cold periods on wax formation in diesel fuel
• The difference between gradual and sudden temperature drops on fuel gelling
• Why individual fuel compositions matter in predicting gelling behavior
• The importance of understanding cloud point and cold filter plug point temperatures
• How uncertainty in exact fuel properties affects preparation strategies

Ideas Worth Sharing:

Here are three notable quotes from the podcast episode:

• "Diesel fuel clouding and gelling doesn't just have to do with how cold it's getting, it's affected a lot by how the temperature goes up and down."
• "Steep and quick temperature drops actually make paraffin waxes come out of the fuel to a greater extent than a gradual or steady decline, even if you're talking about going down to the same temperature in both scenarios."
• "You do not know that short of having it tested. And this margin of uncertainty is going to impact the recommendations for how and when you should prepare for these problems."

Resources:

• Erik Bjornstad: LinkedIn

Show Notes:

[00:00:00] Introduction and recap of previous episode on diesel fuel jelling
[00:01:00] Explanation of how temperature patterns affect fuel jelling
[00:02:00] Introduction to various temperature scenarios
[00:03:00] Scenario 1: Temperature drops and rises above cloud point
[00:04:00] Scenario 2: Temperature stays close to cloud point for days
[00:05:00] Scenario 3: Temperature drops steadily below cloud point
[00:06:00] Scenario 4: Sharp temperature drops and their effects
[00:07:00] Review of key points and preview of next episode
[00:08:00] Closing remarks and call to subscribe

Episode Transcript

(00:00):
Welcome to the Fuel Pulse Showpodcast, where we talk about all

(00:03):
things fuel for all kinds of people.
I'm your host there, Bjorn Stead, andI'm going to be your guide through
the ever changing world of fuel.
Today, we are continuing our FuelPulse Show back to school episodes,
where we go back and we dig into thebasic building blocks of fuel care.
Now, last time, we talked about howdiesel fuels have Jelling problems

(00:27):
because of the effect that coldtemperatures have on their ability
to keep their wax content soluble.
How that wax comes out as crystalsin the fuel, it builds up eventually
to the point where more and more ofit gets caught by the fuel filter
until the fuel flow is sufficientlyblocked that the engine shuts down.
Now we talked about how many dieselfuels have cloud point temperatures of

(00:51):
around 16 to 17 degrees Fahrenheit andcold filter plug point temperatures.
three to five degrees below that.
But the reality is a little bit morecomplicated than just knowing those two
temperature figures because we haven'tconsidered that temperature pattern
also affects this Jelling phenomenon.
Now, what do we mean by that?

(01:12):
Well, let's explain.
Remember we said that depending onThe sizes and the size distribution
of the paraffins in the fuel.
The wax starts comingout, about X degrees above
that cloud point temperature.
And then later, we said that if thattemperature happens to warm back up
above the cloud point, that wax thatcame out, it's going to re dissolve.

(01:36):
It's going to melt back into that fuel.
And then it will come back out the nexttime it happens to get cold enough.
But what if that temperatureactually doesn't warm back up?
What if it stays cold?
Well, if it stays cold, thenthe wax that came out initially,
that can't re dissolve.
It's still in there.
And then the longer it actually stayscold, that wax is going to be joined

(02:00):
by more and more of the other waxcrystals coming out alongside it.
If you get cold weather, for enoughconsecutive days, then you are
more likely to develop enough waxcrystals in the fuel that the fuel
filter is going to get plugged.
Now diesel fuel clouding and gellingdoesn't just have to do with how cold

(02:22):
it's getting, it's affected a lot byhow the temperature goes up and down.
So let's explain.
Maybe the best way to explainthis is to look at a handful of
temperature scenarios, , so that wecan better see what we have to think
about from a practical standpoint.
Kind of things that you probably willsee in your day to day operations

(02:44):
when you look at the temperature.
So first, let's assume for all these thatyou have stored ultra low sulfur diesel
and you assume that it has a cloud pointabout, let's say, 17 degrees Fahrenheit.
So what are some of thesecommon temperature scenarios
you might see during the winter?
Well we've already covered one of them.
A cold front came in, it droppedthe temperature down to 17 degrees.

(03:09):
But then, that was at night, butthen during the day, the temperature
warmed back up to 25 degrees.
The wax that appeared at night, redissolved during the day because
the temperature warmed back up.
And so, you're notgoing to have a problem.
That wax is gone.
No problem.
What about a scenario where thetemperature doesn't drop below

(03:32):
17, but it's close to that?
Let's say it stays between 18 and20 degrees Fahrenheit, but it stays
like that for three or four daysat a time without warming back up.
Now, in this case, some of thatwax will drop out from the fuel.
Some of the fuel's waxcontent will drop out.

(03:53):
And it doesn't really warm back upenough to re dissolve any of that.
However, because it's staying at18 to 20 degrees, it's not really
getting cold enough for all of thatfuel's wax content to drop out.
So you're only gettingsome of it in there.
And so because of that, you may beable to avoid gelling problems under

(04:14):
that kind of temperature scenario.
Now what happens if the temperature's,third scenario, what happens if the
temperature drops steadily over thecourse of let's say a week and it
drops down below the cloud pointto let's say 12 degrees Fahrenheit,
well below the cloud point?
Well now you've got a pretty classicgelling situation where the temperature

(04:37):
got cold enough for substantialwax content to be in your fuel.
And it stayed cold enough for asubstantial part of that wax to come out.
And since it didn't warm back up, thewax didn't have a chance to re dissolve.
That combination of things makesit entirely probable you will end
up with That combination of thingsmakes it entirely possible You

(05:02):
will end up with jelling problems.
And then there's one othertemperature scenario to consider.
And that's if the temperaturehappens, doesn't drop steadily.
What happens if it drops sharply?
Like a cold front comes in andthe temperatures plummet in a
pretty compressed period of time.
What happens there?

(05:22):
Well, steep and quick temperature dropsactually make paraffin waxes Come out
of the field to a greater extent thana gradual or steady decline, even if
you're talking about going down to thesame temperature in both scenarios.
So that's something that youwant to keep in mind as well.
So as you can see, low temperaturesdo matter, but it also matters how

(05:47):
the temperature drops and how longit stays at that low temperature.
And then through all of this,we have to keep in mind that how
these temperatures affect our fuel.
may not be exactly the same as howthey affect our neighbor's fuel.
Because remember, your fuel, orour fuel, isn't exactly the same

(06:07):
as their fuel, even if they're bothnumber two ultra low sulfur diesel.
Then, final thing to keep in mindwith this part is, there's a margin
of uncertainty that you necessarilyhave in this kind of situation.
That uncertainty has to do with notknowing the exact temperature that
your fuel is going to cloud or join.
You do not know thatshort of having it tested.

(06:32):
And this margin of uncertainty isgoing to impact the recommendations
for how and when you shouldprepare for these problems.
And that is what we're going to talkabout in our next episode of the Fuel
Pulse Show Podcast Back to School.
What the best solutions are to preventthese problems, and also importantly,
how to implement them for your fuel.

(06:54):
So, review.
Typical diesel fuel cloud pointaround 16 to 17 degrees Fahrenheit.
Cold filter plug point is 3 to 5degrees colder than that, but it
doesn't just matter how cold it gets,it also matters how it gets there.
A gradual or a steady temperaturedrop allows the paraffin waxes to

(07:16):
come out of the fuel gradually,which lessens the chances of gelling.
But a sudden drop in temperature,Increases gelling chances and having
sustained periods of cold at or belowthe cloud point also increases the
chances that you're going to see gellingproblems because the waxes don't get a

(07:37):
chance to re dissolve back into the fuel.
So, Thanks for joining me today.
If you liked what you heard on today'spodcast and you haven't done so already,
feel free to subscribe at your podcastplatform of choice, whether it's iTunes,
Stitcher, Google Podcasts, whereveryou happen to like to listen and leave
us a review if you can, because thatreally does help other people find it.

(07:59):
So till next time, I am Eric Burenstead.
Thank you for joining us and we'll see younext time at the Fuel Pulse Show podcast.