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Week of 5 February 2024: Transportation Thoughts

Email Jim at jim.thompson@ipulpmedia.com

It is transportation month here at Nip Impressions, and there is a lot to talk about.

I almost titled this first column of the month "Transportation Follies" but then thought better of it. There certainly are many transportation follies in the headlines these days.

However, I thought I would spend this first column of the month in a cerebral fashion. What do you think of when you think about transportation? Cars? Trucks? Airplanes? Railroads? Ships?

We have transportation issues inside our facilities as well as in forestlands, too. Inside our facilities this sometimes involves motive equipment, at other times it involves conveyors.

I once had a consulting assignment with a well-known company in our industry that was building a low-cost facility in a location with very low labor costs. This might have been characterized as a converting plant. Besides keeping the cost down and taking advantage of the low-cost labor, it was their desire to comply with internationally recognized labor safety standards.

After some discussion, I suggested we adopt the old-fashioned bank barn design popular with farmers many years ago (and with many examples still being in use). We developed a concept that was stepped throughout the plant. Raw materials, delivered by truck, entered the high end of the plant. After each operation there was a step down, so the employees never really lifted anything, they just kept guiding work in progress to a lower elevation. This simple design eliminated nearly all lifting hazards.

But let's spend a bit of time looking at the elements of transportation, whether it is a bar of soap discharged from the plodder (a machine that makes soap bars) to the wrapper, or 5,000 tons of pulp from Brazil, headed to a tissue mill in the Middle East, there are similar elements to all transportation.

First, the idea is to get an item from Point A to Point B, usually thought of as a horizontal experience.

But the devil is in the details.

There may be elevation changes. A rise in elevation requires additional energy and a lowering of elevation can give off energy, sometimes in the form of braking, as heat energy, or in other cases, such as a Toyota Prius, a Tesla, or a train engine, a recovery of energy.

If the horizontal travel is faster than about 20-30 miles/hour (30 - 50 km/hour) wind and/or boundary layer effects come into play. Example, I was on the startup of a new paper machine. The top wire saveall pan on the fourdrinier was too close to bottom wire. At speed (approximately 60 miles/hour), a vacuum was created at this point and pulled the bottom wire into the pan, destroying the paper web. Perhaps you did not think of this as a transportation issue, but it obviously is.

Trains have the best advantage when it comes to these wind effects. After the front engine has poked a hole in the local atmosphere, the train is only dealing with the drag over the train cars, a more manageable energy loss.

There are other energy losses, too. Getting the energy from the motivating source (engine, electric motor, etc.) creates losses in gearing and, if on the road, losses in the flexing of rubber tires (and trains do not have this last one).

It is difficult to obtain a high theoretical efficiency from source to final objective when it comes to transportation.

But I will leave you this week with a story I heard at a recycling conference in Washinton, DC, about 1990 (long before we became as politically correct as we are today). A professor from a European University gave a talk on recycling. His example was a ship hauling OCC from the US East Coast to Rotterdam. By his calculations, had the ship burned the paper it was carrying instead of the normal bunker fuel to get the energy to make the trip, the ship would have been empty when it got to Rotterdam. He thus left the audience with the question, what are we doing here?

There are many questions like this we seem to be ignoring these days.

Transportation Follies

Be safe and we will talk next week.

________

Other interesting stories:


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