As we illustrated last week by proposing a vertical paper machine, many of the issues and configurations we take for granted were developed long ago and were necessitated by the technology of the day.  Perhaps stupidly, and often blindly, we exert our efforts toward improving systems that, when one steps back, should simply be thrown out and replaced with what is available today.

Forming wires may be a good example of this.  

For instance, rather than a moving wire, what if we had a very slick stationary surface with many tiny properly engineered holes in it? Then to propel the sheet "down the wire" we did the following.

Behind the slick stationary surface, we had hundreds of micro vacuum boxes.  By micro, I mean they are very small.  Each has its own control valve to turn the vacuum on and off.  Then, using a sophisticated control regimen, the boxes are turned on and off in a sophisticated, advance pattern, thus moving the sheet as it forms down the slick surface while draining the water at the same time.

I think it is possible.

I also think we can form a superior sheet this way. No wire marks.  Perhaps no streaking.  And certainly no drives, cantilevered forming sections and other claptrap that just exists because we have always done it that way.

I have to say that I admire your out of the box thinking, but I am sorry that I don't understand the purpose of your vision. I guess that everything can be engineered with today's technology to suit this vision. But is it cost effective? Is this vision more efficient, improved product quality, improve maintenance, operator friendly, improved employee safety, and etc.  I cannot see any advantage to support a vertical paper machine from my viewpoint. The massive structure for such a machine would be very costly, not to mention the redesign of all the support equipment for such machine. $$$$

It is my belief that we need to improve the horizontal machine first, as they already exist, to be more efficient in all aspects of papermaking, many under explored opportunities.  

Bill Avent

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Thanks for presenting challenges! Without them we might not be living in caves still but hardly having all the fancy gadgets which, if used the right way, are improving efficiency, making things easier to use and turning our work more rewarding.

What comes to your idea of vertical PM, you for sure know that you´re not the first, nor alone. I don´t know any paper machines built this way, but if we look into a pulp mill, there this idea in part is the most common concept. Today, drying is not done using cylinders, but before the domination of dryer chambers, the cylinder driers were stacked.

What I feel would be the most feasible way to improve the current PM concept might not be a copy of  today´s machine, just positioned vertically. If we leave for future the discussion about substitution of drying cylinders by some other devices, I would suggest leaving wet end, up to presses, as they are today. The reason: This is the heaviest part of the PM, has most connections, needs regular maintenance of wire and felts, e.g, and would require a truly massive structure to support the machinery filled with liquid and the operating platform. Cannot see savings or operational improvements.

The dryer, in the contrary, might well be wort tipping. It´s relatively light structure and has less interfaces. I just wonder the even distribution of heat: hot air, as we know, tends to go up, thus increasing temperature in the top of the hood.

Copying from Pulp Dryer, the reel and winder could stand on the ground floor, they do not need space underneath, unless pulper pits, as does wire part.

What would be the gain? I´m not sure, to say the truth. A shorter building, shorter (but more robust) dryer foundations, no operation floor in the dry end. Lighter building frame for dryer part because there´s no heavy duty bridge crane.

As a matter of facts, why locate stock prep under the wire? Couldn´t they be located aside? Wider building but easier construction and easier construction sequence.

Keep innovating and challenging us!

Markku Metsäranta

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There were many, many comments on Linkedin as well.