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Kelly H. Ferguson is
V.P., Editorial
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Editor's note: In the March issue of Pulp & Paper, I wrote a From the Editors column titled "On-demand papermaking?" (P&P, March 2002, p. 3) that discussed the concept of a paper machine running more like a printing press. The column explored the possibility of faster order fulfillment to minimize inventory and better satisfy customers. Included was some discussion of the barriers of technology and the business mind-set within the industry. Following the column's release, the magazine received numerous letters regarding the concept, its failings, and its possibilities. Included below is a sampling of these letters.
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I enjoyed your editorial in the March edition. Working Lean Principles into the paper industry will be a challenge, but maybe it's the mind-set that will help North America survive. It certainly would have prevented the low prices caused by large inventories in the late 90s.
Brian Frost
Appleton Papers
Via email
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Interesting to read your idea about just-in-time papermaking. That is actually what has driven our development of the POM Concept since 1992. At TAPPI Papermakers 1993, I presented a paper about this, and the ideas have developed a lot since then.
The basic idea is that in the process there are some parts that are slow and heavy, responding slowly to changes. The most prominent of these is the stock system and paper machine approach. The basic premise is that it is impossible to control something faster than it responds or changes (by anticipating you can, of course, make a concerted change).
If we have the components for a paper grade ready-made, we can change the mix very fast and close to the paper machine, minimizing the response time for a change. The question merely is how fast changes can be brought to the headbox and how much spreading happens before it (the ideal would be a clean plug flow).
The second obstacle, then, is the circulations around the paper machine, which delay reaching equilibrium. By minimizing circulation volumes, one can minimize cycle times, accelerating the reaching of equilibrium. Now this is easily said but more difficult to accomplish. On the other hand, many changes are quite simple, with the obstacle being tradition and conservatism among papermakers.
In theory you can arrange a paper machine wet end circulation for about 10 seconds, which would permit any grade change (6 cycles) to be made in less than a minute.
In practice we have already reduced volumes and grade change times to a fraction of those accomplished with a traditional system. For instance, one paper company makes any color change in less than half an hour (even from black to white). When we move ahead with the development of new screening and fiber recovery concepts the practical times will be quite short.
The rest of the papermaking process is mechanics (and, of course, thermics) which can be handled or passed by process automation and management.
I was a vice president of Business Development with Ahlstrom Paper in the 1980s. At that time, together with the Boston Consulting Group, we made an analysis of our strategic cost structure. The main finding was that the strongest factor driving costs in our paper business was production changes. Its influence on competitive cost§i.e., cost difference related to competition§was the production program. The better focused a paper machine was and the better its products fitted each other, the more competitive it was. We found that the influence of fit and focus was far greater than that of any other one, like factor costs (raw material, labor, energy), scale, technological level, and so on.
The reason for this was the great losses involved at any change made on the machine, which involved downtime, off-grade production, web breaks, and non-optimal tuning of the process. This is something that "every" papermaker knows at least intuitively, but we made a model quantifying the influences.
The other side of the coin, of course, is that products requiring short runs also command a correspondingly higher price that award those who are able to make the short runs. These are reasons why I took the challenge of resolving the problem or developing the opportunity.
Paul Olof Meinander
POM Technology Oy Ab
Helsinki, Finland
Via email
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To do short production runs and quick grade changes, one of the major needs is understanding and control of dynamic process change. With the industry's traditional "bigger and faster" mind-set, we have put a huge effort into establishing and maintaining steady-state operating conditions and then optimizing that state.
Only recently have we seen much effort into understanding dynamic process changes, and even that work is focused on how to detect and minimize "upsets," as we call them. What we will need to do more of is learning to control dynamic changes so that they become a tool for operations and a way to minimize off-spec product as grade changes are made. As a style of doing business, short runs and rapid grade changes will only be welcomed when we are happy and comfortable doing them.
Ken McLellan
Provincial Papers
Via email
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You will not have heard of my company because most fonts of foundry type do not contain enough zeros to express my share of the world production of pulp and paper. In fact, our pulping vessel is a 40 gal kettle (in which we process raw non-wood fibers such as hemp, flax, kenaf, and similar materials), and our daily production of paper is usually less than 100 sheets of handmade paper, 18-in. x 24-in.
But we are also involved in a larger scale project to set up commercial production of non-wood fiber pulp. (With a capacity of 15 tpd, this is still a "micro-mill" by industry standards.) Ordinarily, I would not presume to intrude our activities upon your attention, as most of your coverage is understandably at the other end of the spectrum of producers, but since you express interest in the "small and efficient" end of the evolution in pulp and paper technology, here are the most accurate numbers which our engineers are able to give us: that a mill which could produce 15 tpd of very efficiently delignified pulp (from the whole stalks of bast fiber plants: hemp, flax, kenaf, jute, etc.) could be built for under $4 million, and the cost of the pulp produced would be in the range of about $360/ton.
The intention of such a small design is that such a mill could be owned and operated within the farm community where the alternative fibers were being produced (either as a fiber crop or as a byproduct, like seed flax straw). This would eliminate a lot of transportation cost, which is very inefficient when it comes to raw materials. The ratio of value to shipping costs is greatly improved when the farmer can first convert his material to clean, pure cellulose pulp instead of shipping out bundles of raw stalks.
So, instead of a large, central pulp mill, you could have many small mills, some producing different kinds of pulp, all supplying one central paper mill, which is still imagined as pretty large. As far as I have been able to figure out, the advantages of making paper on a large scale are going to be very hard to overcome in a small papermaking operation, but at least I can really see a niche for these little pulp mills.
I am also trying to make a micro-mill for paper production. My plan is to make a micro production of about five tpd of the very finest nonwood fibers available, such as the decorticated bast fibers of hemp, flax, or kenaf. Our product would be a premium art quality paper, which we expect could be easily priced at a level that would ensure profitable operation of such a small scale. Basically, what I am trying to do is to make low-cost, commercially-produced paper of the same quality that I now make by hand, standing at the vat with a mould and deckle.
Is any of this happening? I sure hope so. The only obstacle is the usual one§the financial support for these projects. If anyone is interested in participating with either of these projects, both are fully ready, turnkey designs. For instance, I already have the locations of proposed mills, the availability of fiber resources, and the use of a small paper machine all lined up. The pulping technology is the drip percolation process with organic solvents pioneered by Krotov in the Ukraine.
John Stahl
Earth Pulp & Paper/The Evanescent Press
www.tree.org/ep.htm
Via email
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I appreciated your thought-provoking article "On-demand papermaking." I hadn't made this connection, and I thought you highlighted the key considerations well.
You asked for thoughts on the subject. That's all this is.
The USDA Forest Products Laboratory in Madison, Wis., has a complete "pilot-scale" paper machine, including pulping. Perhaps it could be used as a test bed for experimenting with rapid, automated product/grade changes.
Paper machines and pulping have become more automated over the years, but papermaking is still an art, and experienced papermakers are essential to tuning the process from the basic operational formulas and parameters to optimal production. Once the process is tuned for a particular grade, it generally runs pretty smoothly, though there are somewhat unpredictable variations in the materials that require monitoring and corrections on the fly, and there's always the possibility of a break.
In time, however, it seems possible that tuned operating conditions for various products and grades might be recorded and used to program for rapid, automated changeover. Eventually, systems may even "learn" to adapt for process variations. I would not be surprised to see papermakers initially skeptical of or even resistant to this concept.
Tom Tolman
Evergreen Engineering
Via email
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The printing industry is way too fragmented, and the distribution channels are way too complex, for this to ever happen.
Pat Hurd
Georgia-Pacific Corp.
Via email
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I read your article with interest and surprise. Finally somebody is beginning to think. Very high investment and very low return on investment have been the history of this industrial sector. The same way as it was on the Studebakers and Packards and great big gas guzzlers made by Ford and GM, until somebody started thinking. And the little Beetles and Renaults and Nissans came into the act.
Then somebody kept thinking and decided to please the customer. If somebody wanted a yellow car with red interior, no stereo, a sun roof, and all factory installed, they would have it in a very short time. And then the same is true for the old gentlemen who wants the same car but in black with gray interior, no sun roof, and no stereo. To my understanding, Lee Iaccoca started this with the Mustang. Then, the Japanese got the idea and used it to beat the Americans on the market. Somebody called it "flexible production plants" against "dedicated (one grade) production plants."
Flexible plants were invented many years ago. It was a lot of very hard work. Grade changes will always be hard work, and in the past it would take one to three hours to make a grade change. But now, there are computers with which you can program your grade change.
I know that in a large corporation, one of the mills with the highest return on investment is a mill with about 40 to 60 grade changes a week. It is a mini-, mini-, mini-mill. The computer programs were made in a garage by a group of young engineers. (Do you hear something familiar?)
At the last TAPPI meeting I attended, somebody presented a grade change technology for fast furnish change response. The facts are that warm water has been invented, lighters have been invented also, but the sector does not want to invest in "human capital" because it is a lot of very hard work.
So I conclude, flexible plants and flexible production are invented. The problem is that the industry has invested heavily in capital assets and very little in human capital. But, the market is forcing them to change. The Japanese used the lesson.
Dr. Eng. Javier Ortiz
Via email
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What a great idea. The first thing that came to my mind was rental of a particular paper machine. Not a new idea, but with all the "old" machines being shut down all over the country, surely some of these might be reconfigured for a particular grade and run efficiently on small orders for that grade. Of course, converting facilities would be part of the package, but why not put some of these old machines back to work rather than trying to develop a new "package" that might take years to develop and put on the market?
I used to do quite a bit of contract engineering at the Boise Cascade mill in St. Helens, Ore. There was one tissue machine that was rented, on contract, to an outside producer for the production of their particular grade. I assume that was not the only such agreement in the country. If these retailers are in desperate need for quick response on boxboard grades, slick magazine sheets, or any other paper grade used in their packaging, advertising, or pricing manuals, the tonnage required would not be the 2,000-tpd monsters that drain revenue during the cyclic downturns we have experienced for the long 50 years I have been associated with the industry.
Just a thought. I hope you get many ideas from mill people, engineers, and suppliers. Sounds like one of them could be a winner. But, let's do it quickly. You know that as soon as the industry thinks things are getting back to "normal," another buying spree will start, and in a few years we'll be back where we are right now.
D. Carl Yackel, P.E.
Consulting Engineer
Lake Oswego, Oregon
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