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发表于 4-1-2019 16:13:13 | 只看该作者 回帖奖励 |正序浏览 |阅读模式
Michael Corkery, The Great American Cardboard Comeback. New York Times, Mar 24, 2019 (in the SundayBusiness section).
https://www.nytimes.com/2019/03/22/business/cardboard.html

Quote:

"The village of Combined Locks, Wis, founded when the mill opened in 1889 [The mill was closed on Sept 21, 2017 but bought and reopened] * * * Then something unexpected happened: Amazon and China [the latter's only role was to ban import of American recyclables] * * * e-commerce has fueled demand for billions more square feet of cardboard.

"Since reopening, the mill in Combined Locks has switched most production from white paper to brown, installed equipment that can crush used cardboard to make new paper, and hired back about half of the 600 workers laid off during the shutdown.
The smooth brown paper they produce goes to cardboard-making vendors, who sell it in turn to Amazon and other [e-]retailers

"Brown paper sales slowed following the Christmas e-commerce rush, but industry analysts say the conditions are still ripe for long-term growth. That's where China comes in. Until early last year, much of the used cardboard consumed in the United States was being shipped to China [otherwise freight ships would have left US for China empty-handed], where it was recycled into new boxes [with which to ship goods to US].  Then, in January 2018, China stopped accepting most used cardboard imports. * * * for American paper companies that make new cardboard out of used boxes, China’s clampdown has been a boon. It has created a glut of cardboard scrap that is allowing American mills to obtain their most vital raw material at 70 percent less than it cost a year ago.

"Its workers [at the paper mill in Combined Locks] almost never say they are 'manufacturing' or 'producing' paper. They say they are 'making' paper, reflecting how the process is still thought of as a craft with a history that dates back to China in 105 AD.

"On some days, the odor of rotten eggs hangs over the village, a smell some residents attribute to another mill in a nearby town that uses sulfur to break wood down into pulp.  'I've heard,' said Ben Fairweather, head of operations at the Midwest Paper mill [the new name of the reopened mill], 'some people say that is the smell of money.'

"A few miles down the Fox River, in the city of Appleton [situated between Village of Combined Locks and Lake Winnebago; about 3 air miles west of Combined Locks], sits the Paper Discovery Center museum and the Paper International Hall of Fame. Located in a former mill, the modest shrine honors those whose 'accomplishments have truly revolutionized civilization.' Johannes Gutenberg, the inventor of the printing press, has a plaque on the wall. So does Wang Zhen, creator of the world's first mass-produced book in 14th-century China.  Wisconsin has contributed its share of greats to the pantheon of paper. Morris Kuchenbecker, a retired package design engineer from the city of Neenah, patented a series of frozen-food cartons. Ernst Mahler, a chemist, invented the technology that makes tissues soft.  The region's paper history dates to the years following the Civil War, when mills sprung up on along the Fox River to feed the industrializing nation's demand for reading and writing material and disposable towels. * * * Wisconsin remains one of the nation's largest paper producers, and much of it is still made in giant mills along the Fox. Today, huge conglomerates like Georgia Pacific [was founded by Owen Robertson Cheatham in 1927; based in Atlanta, Georgia], along with a handful of smaller companies, produce paper in the Fox River Valley area. But the industry has been contracting for decades, and it is not only because of the internet * * * n 2000, there were roughly 49,600 paper manufacturing jobs in Wisconsin, according to state figures. By 2017, that work force had declined to about 30,000 * * * Ms [Aorica] Hendriks [of Combined Locks mill], 44, worked her way up from the lowest rank to the role of 'coating tender,' applying the starch that make paper more rigid.

"Over the years, the mill’s products reflected the world’s evolving uses of paper: phone books, carbon-copy paper, paper for large printers. The company also had a string of owners. * * * In recent years, demand for glossy brochures [with white background; used in advertising], the mill's biggest moneymaker, kept falling [as advertising has migrated to internet]. * * * When the mill closed in 2017, most of its workers were able to find manufacturing or warehouse jobs. But these typically paid less than their unionized jobs at the paper mill.  Ms Hendriks got a position at a plastics factory earning about $17 an hour, about $11 less than she made at the paper mill. * * * In September 2017, it [Combined Locks paper mill] was purchased out of receivership * * * The mill’s new owners, who called themselves Midwest Paper Group [naturally based in Village of Combined Locks]* * * Across the country, [due to surge in e-commerce] failed white paper mills were being converted to brown to feed the cardboard-box boom, and Midwest followed suit.

"The Chinese paper company Nine Dragons has acquired a handful of paper mills in Maine, Wisconsin and West Virginia and increased brown pulp and paper production. With China constricting imports of used cardboard, Nine Dragons bought the mills in the United States partly to get closer to the country's plentiful source of scrap paper. Another major player is the Kraft [that is Robert Kraft; he is charged with patronizing prostitutes] family, which owns a paper mill and a cardboard boxing plant, in addition to the New England Patriots. * * * A big step was persuading the union to agree to a new set of working conditions. The pay stayed largely the same — an average hourly wage of $25.50 — but the company would not contribute to 401(k) funds. Most significantly, the workers would be required to take on duties that previously had been performed by several employees [early in the report -- at paragraph 7 to be exact -- Midwest Paper Group 'hired back about half of the 600 workers laid off during the shutdown']. * * * Under the new business plan, the mill was not only a paper producer, but also a large recycling facility. The new owners installed an old corrugated container machine, known as an OCC [which stands for 'old corrugated containers' where container means cardboard], a towering vat of swirling warm water, where large bales of used cardboard boxes are dumped and then ground into the stock that makes the new brown paper. * * * The OCC turns the boxes into a thick, brown gruel. That mixture is then strained of plastic tape, staples and other debris before being pumped into the paper machine. * * * The plan to convert the mill to brown paper made business sense to the laid-off workers. They all shopped online and saw the opportunity in cardboard — or containerboard, as it's known in the industry.  But many questioned whether the mill would be able to make brown paper after decades focused on white. The fibers are coarser, which puts more wear on the machines. The Combined Locks mill also lacked a 'shoe press' that traditional brown mills use to wring out water [of course the new management would buy shoe press].  'Brown is a different bird,' said Jerry Meulemans, who is known around the mill as Grizz [from grizzly] because of his personality on the job. ('I can be a bear to work with.')  Papermaking is almost entirely automated. But the product is still largely a byproduct of nature, and the process can easily be foiled by the slightest variable.  The key is getting the wood fibers in the pulp to bind by using a combination of heat and pressure. With belts and rollers moving at about 25 miles per hour, the machine transforms the soupy pulp into a giant roll of rigid paper that resembles warm, earthy-smelling bread in seconds. If one element isn't calibrated correctly — too much moisture, a splotch of bacteria — the paper can tear and the roll has to be made again. * * * At 7 am on Dec 11, 2017, workers gathered for an all-hands meeting in a large, wood-paneled conference room. [Two days later, the mill restarted.]

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5#
 楼主| 发表于 4-1-2019 16:15:00 | 只看该作者
(e) in the last quotation

all hands (n) or all-hands (adj)
https://www.merriam-webster.com/dictionary/all%20hands

is from maritime term "all hands on deck."

(f) chemistry of kraft process made simple
(i) Chapter 2 The Pulp and Paper Making Processes. In John H Gibbons, Technologies for Reducing Dioxin in the Manufacture of Bleached Wood Pulp; Background paper. DIANE Publishing, 1989, at page 17
https://www.princeton.edu/~ota/disk1/1989/8931/893104.PDF
("Most paper is made from wood fibers, but rags, flax, cotton linters, and bagasse (sugar cane residues) are also used in some papers. * * * Wood is composed of: 1) cellulose, 2) lignin, 3) hemicellulose, and 4) extractives (eg, resins, fats, pectins, etc). Cellulose, the fibers of primary interest in papermaking, comprises about 50 percent of wood by ovendry weight. Lignin, which cements the wood fibers together * * * The pulping process is aimed at removing as much lignin as possible without sacrificing fiber strength, thereby freeing the fibers and removing impurities that cause discoloration and possible future disintegration of the paper. Hemicellulose is similar to cellulose in composition and function. It plays an important role in fiber-to-fiber bonding in papermaking [the takeaway is hemicellulose is desirable in final product; I will spend no more time on this]. * * * The fiber from nearly any plant or tree can be used for paper. However, the strength and quality of fiber, and other factors that can complicate the pulping process, varies among tree species. In general, the softwoods (eg, pines, firs, and spruces) yield long and strong fibers that impart strength to paper and are used for boxes and packaging. Hardwoods, on the other hand, generally have shorter fibers and therefore produce a weaker paper, but one that is smoother, more opaque, and better suited for printing. Both softwoods and hardwoods are used for papermaking and are sometimes mixed to provide both strength and printability to the finished product")
(ii) " * * * chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose."  en.wikipedia.org for paper.
(iii)
(A) All naturally occurring form of glucose is D-glucose. L-glucose is man-made.
(B) Glucose is optically active. In the Fischer projection (Fischer was German), a linear glucose has hydroxyl group (-OH) to the right of C5 in D-glucose, and the hydroxyl group to the left of C5 in L-glucose.
(C) You need not comprehend (C) to (E).In water solution, glucose is overwhelmingly in a hexagonal ring -- linear and pentagonal forms are rare.
(D) Haworth projection
https://en.wikipedia.org/wiki/Haworth_projection
(was named after the English chemist Sir Norman Haworth)

demonstrates D-glucose has C1 in α (hydroxyl group down) or β (hydroxyl group up).
(E) Starch (in plant) and glycogen 肝糖 (in animals) are polymers of glucoses, so are cellulose (major component of plant cell wall). However, cellulose are strictly linear (with glucose end on end, linked by ether bond in β(1→4) linkage), whereas starch and glycogen both have side chains and linked by either bond in α(1→4) linkage for the trunk with branches by α(1→6) linkage.
(F) To ensure strength of paper, you do not want to weaken or break the ether bond in cellulose. The breaking of ether bond in chemical pulping us inside lignin.
(iv) 10.2 Chemical Wood Pulping. In Chapter 10 Wood Products Industry, of Compilation of Air Pollutant Emissions Factors (AP-42). 5th ed. vol 1
US Environmental Protection Agency,
https://www3.epa.gov/ttnchie1/ap42/ch10/final/c10s02.pdf
("The kraft process alone accounts for over 80 percent of the
chemical pulp produced in the United States. * * * The kraft pulping process (see Figure 10.2-1) involves the digesting of wood chips at elevated temperature and pressure in "white liquor", which is a water solution of sodium sulfide and sodium
hydroxide. The white liquor chemically dissolves the lignin that binds the cellulose fibers together. * * * The characteristic odor of the kraft mill is caused by the emission of reduced sulfur compounds, the most common of which are hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide, all with extremely low odor thresholds [ie, one can smell these chemicals even in minute amounts]. * * * Although odor control devices, per se, are not generally found in kraft mills, emitted sulfur compounds can be reduced by process modifications and improved operating conditions")

My guess is AP stands for air pollution.
(v) Arthur J Ragauskas, The Chemistry of Wood and Kraft Pulping. University of Tennessee, Knoxville (UTK), undated
http://biorefinery.utk.edu/techn ... %20Kraft%20Pulp.pdf

The entire Web page is informative. Pay attention to page 19 which shows nucleophilic sulfur cleaves the ether bond to release aryl group in lignin.
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4#
 楼主| 发表于 4-1-2019 16:14:27 | 只看该作者
(d) Wang Zhen and Ernst Mahler in quotation 6
(i)
(A) 王祯 (fl[ourish] 1290–1333 [Yuan Dynasty (1271–1368)]; wooden movable type printing technology)  en.wikipedia.org for "Wang Zhen (inventor)".
(B) 活字印刷术
https://zh.wikipedia.org/wiki/活字印刷术
(section 2 在中国的發展, section 2.2 木制活字)
(ii)
(A) Ernst Mahler
https://en.wikipedia.org/wiki/Ernst_Mahler
(1887 (Vienna, Austria) – 1967; took employment with Kimberly-Clark in Neenah [where Fox River leaves Lake Winnebago], Wisconsin; "His development of creped wadding, a soft and fluffy absorbent material, became over time one of Kimberley [sic]-Clark's most important products and the source of billions of dollars in global sales. During World War I, creped wadding made from paper had been developed as a cotton substitute for surgical dressings; under Mahler's commercialization process, It became the basis of such well-known products as Kleenex and Kotex")
(B) The German and Jewish (Ashkenazic) Mähler meant "a painter, especially a painter of stained glass, from an agent derivative of German malen to paint."
(C) Kimberly-Clark Corp  (the two were founders' surname; founded in Neenah, Wis in 1872 and moved to Irving (Dallas suburb], Texas in 1985)  Wikipedia.
(D) Search images.google.com with (creped wadding how) and you will see what a roll of product looks like.
(E) Michelle Malkin, Who Built That; Awe-inspiring stories of American tinkerpreneurs. Threshold Editions/Mercury Ink (of Simon & Schuster), 2015, at pages 109-110
https://books.google.com/books?i ... 0mahler&f=false
("Kimberly & Clark lead scientist Ernst Mahler invented creped cellulose wadding from sugar cane [as opposed to wood chip] pulp. The tissue, used as a substitute for scare surgical cotton dressing to treat soldiers' wounds, saved countless lives during World War I. Thanks to Kimberly & Clark's brilliant marketing and product development teams, cellucotton became the foundation of its Kortex and Kleenex personal hygiene lines, which today are just two of the Fortune 500 company's billion-dollar brands")
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板凳
 楼主| 发表于 4-1-2019 16:13:59 | 只看该作者
(c) For sulfur in quotation 5, see paper chemicals
https://en.wikipedia.org/wiki/Paper_chemicals
(section 2 Pulping)
(i) Lignin is found in plant (but not, say, bacterial) cell wall. The word is derived from Latin noun neuter lignum for (fire)wood.
(ii) kraft process
https://en.wikipedia.org/wiki/Kraft_process
(One of the main chemical reactions that underpin the kraft process is the scission of ether bonds by the nucleophilic sulfide (S2−) or bisulfide (HS−) ions")

Quote: "The kraft process (so called because of the superior strength of the resulting paper, from the German word [noun feminine; recall all German noun has the first letter capitalized] Kraft for 'strength') was invented by [ethnically German] Carl F Dahl in 1879 in Danzig, Prussia [which is present-day Gdańsk, Poland]. * * * It [another invention: recovery boiler] enabled the recovery and reuse of the inorganic pulping chemicals such that a kraft mill is a nearly closed-cycle process with respect to inorganic chemicals, apart from those used in the bleaching process. For this reason, in the 1940s, the kraft process superseded the sulfite process as the dominant method for producing wood pulp. * * * Pulp produced by the kraft process is stronger than that made by other pulping processes and maintaining a high effective sulfur ratio or sulfidity is important for the highest possible strength. Acidic sulfite processes [solution in sulfite process can be neutral or basic, depending on chemical used, but that in kraft process is always basic] degrade cellulose more than the kraft process, which leads to weaker fibers. Kraft pulping removes most of the lignin present originally in the wood whereas mechanical pulping processes leave most of the lignin in the fibers. The hydrophobic nature of lignin interferes with the formation of the hydrogen bonds between cellulose (and hemicellulose) in the fibers needed for the strength of paper

(A) Note "ether bonds" -- not "either." Still this Wiki page fails to say which ether bonds, because there are many kinds in wood, some desirable and some others not (from the point of papermaking). See (f).
(B) More about graft process will be discussed in (f).
(C) Dahl (surname)
https://en.wikipedia.org/wiki/Dahl_(surname)
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沙发
 楼主| 发表于 4-1-2019 16:13:32 | 只看该作者
My comment:
(a)
(i) This is a lengthy report, The report took up 2 1/2 pages in print, though it both included large portraits of workers (who care) interviewed and digressed A LOT (with unwanted details). There is no need to read the rest.
(ii) Paper mill, Combined Locks, Wis. Library of Congress, undated
https://www.loc.gov/item/2016794365/
("Contributor Names[:] Detroit Publishing Co, publisher[;] Created / Published[:] [between 1880 and 1899]; Library of Congress Control Number[:] 2016794365")

(b) geography
(i) History. Village of Combined Locks, undated
http://www.combinedlocks.org/community/history/
("The actual Village of Combined Locks had its origin as a mill town, linked to the pioneer paper industry of the Fox River Valley. The farming community changed into a village when the present Combined Paper Mills, Inc was organized as the Combined Locks Paper Company in 1889. The first dam at this place in the Fox River, along with the original pulp mill buildings, was built that year")
(ii) Fox River (Green Bay tributary)
https://en.wikipedia.org/wiki/Fox_River_(Green_Bay_tributary)

Village of Combined Locks lies between Lake Winnebago and City of Green Bay (which is about 25 air miles northeast of Combined Locks).
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