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NEW SOURCES OF PAPER STOCK.'
By ARTHUR D. LITTLE.
The most significant development of the year in paper making has been the serious and general inquiry all over the world for new sources of paper stock. Wood is undoubtedly destined to maintain a position as one of the chief sources of supply for an indefinite number of years, and no possible substitute for ground wood is even in sight. There are nevertheless for those who will read them plenty of signs that we are on the eve of a readjustment in paper making methods. For a considerable number of years the makers of many sorts of paper have found themselves in a position where it was wood fiber or nothing else as their raw material. This general use of wood fiber as the only available basis for many branches of the industry has made for a greatly increased production, but it has not always made for improvement in the quality of product. To the growing scarcity of pulp wood, the continually rising price and longer haul with which paper makers using this material are now contending, will in a few years be added the competition of new and better stocks which even now can be produced more cheaply than any bleached wood fiber. The time is rapidly approaching when we shall see upon the market many new paper stocks as bleached and unbleached pulp and half-stuffs, and these will be as readily available for immediate use as bleached sulphite is today. This means of course a gradual displacement of wood fiber from its present position of supremacy. It means also a far wider range in the quality and characteristics of available raw materials, as a result of which variety will come a broader scope for the exercise of a critical judgment and a greater skill on the part of the paper maker in the selection and manipulation of his materials. This condition is bound to react to the advantage of the industry generally, and especially to the advantage of the smaller mills in the hands of expert and progressive manufacturers. There should follow a decided rise in the standard of quality, particularly in bag and wrapping papers, and in those papers which may be expected to replace the cheaper grades of book, wood writing and envelope as now manufactured. At the same time the range of possible production in many mills will be extended.
As these expectations will hardly be accepted on their face, it is well to inquire into the basis upon which they rest.
Wood as a raw material has proved so available, convenient, compact,
'From the Report of the Official Chemist of the American Paper and Pulp Association.
easily handled, and heretofore so cheap, that we have been led to overlook or ignore the immense sources of other and better paper stocks which lie easily within our reach. It is therefore proposed to devote the major portion of this report to indicating what these other materials are, together with a brief statement as to their character and limitations, and what may reasonably be expected of them. This statement will serve its purpose if it convinces you that we are not dealing with the perennial suggestions of visionaries who see a paper stock in everything which has a fiber, but are instead concerned with the serious proposals of capable technologists whose conclusions are based on careful study,
Let us consider first the material available in our own country and now wasted with our characteristic national improvidence... The first. in importance of these is undoubtedly the waste flax straw of our northwest. The total area grown to flax for seed runs as high in some years as 3.700,000 acres, which means roughly a strip a mile wide and over 5,700 miles long. A ton and a half of straw to the acre is said to be moderate yield, upon which basis we have over 5,000,000 tons of straw a year. This straw contains more than 20 per cent of linen fiber, so that, disregarding the inconsiderable amount of the fiber which is worked into tow. binder twine, and a few other similar coarse uses, there is here available more than 1,000,000 tons a year of the finest paper stock, equally suitable for the highest grades of paper as well as for bag and wrapping papers of a quality not now approached. It would be hard to find another country in which such a waste would be permitted.
Within the last year at least three machines have been perfected for separating the short fiber which adheres to our southern cotton seed after the cotton has been ginned. An average cotton crop may be counted on to yield at least 600,000 tons of this short fiber which now goes into cattle feed to the detriment of the latter. One meets occasionally with paper makers who have tried the fiber but who almost invariably condemn it as unworthy of serious consideration. Within the last few weeks a writer in an English journal stated with much positiveness that this cotton hull fiber was "only suitable for browns and wrappings." The real fact is that this fiber is easily reduced to a pure white stock wholly free from any sign of hull, and a failure to secure as good results from this neglected fiber as from a good grade of cotton rags is a reflection upon the skill of the man who tries to handle it rather than upon the quality of the fiber itself.
In my report of last year I referred to the fact that on the average 22,750,000 tons of cotton stalks are each year burned or plowed under, or otherwise wasted. These stalks have a woody structure which lends itself readily to treatment by the sulphite process, yielding a fair proportion of fiber well suited for the production of paper of the lower grades. It is, of course, not feasible to attempt the removal of the bark, but this is so broken up and distributed through the sheet as to be unobjectionable in papers for
a wide variety of use. There are, however, undoubted difficulties in the way of the preliminary handling, transport and storage of the material by reason of its bulk.
Somewhat the same difficulties are encountered in any large scale attempt to utilize the first-class fiber which in almost unlimited amount has been shown to exist in the outer shell of the corn stalk.
The exceptionally high tides which occur in the gulf of California during the full moon of May each year, acting together with the melting snows from the mountains, cause the Colorado River to overflow its banks along its lower reaches, which are thus built up of rich alluvial soil. The climate is almost tropical, the temperature often reaching 135° in the sun. Great stretches of this country are covered with wild hemp which under these favoring conditions grows luxuriantly. Many tracts are over 100,000 acres in extent. No data is available as to the yield of fiber, but hemp is known to grow to a height of 15 feet in eighty days, and to yield 1,500 to 2,000 pounds of actual fiber per acre. I need not tell you that this fiber is of the very highest grade for any of the purposes of paper making.
Flax is pre-eminently a crop for new lands, and is often the first crop sowed after such lands are turned over. Great crops of flax for seed are therefore naturally raised in Canada, particularly in Manitoba and the Canadian northwest. Up to this time little or nothing has been done in the way of utilizing the fiber, although the Canadian flax should prove more valuable than our own by reason of the greater care taken in harvesting, the flax being cut or pulled and kept straight in sheaves while the seed is being separated.
The so-called marsh hay which is said to closely resemble esparto in structure and the paper making quality of its fiber, grows wild in great abundance over large areas in Canada, while the American wild rice, Zizana aquatica, also grows in such profusion that 100,000 tons a year are available on the shores of the Canadian lakes alone. Paper making tests made in England rank this fiber also with esparto.
Especially noteworthy in the developments of the year is the serious and general revival of interest in bamboo as a source of paper stock. Its superlative value for this purpose was urged, you will remember, by Routledge in 1875 after his introduction of esparto into England. You may also remember that my report of last year refers to the very favorable conclusions as to bamboo reached by R. W. Sindall in his report to the British government on available sources of supply of paper stock in the British colonies. These conclusions are now amply confirmed by Raitt, who has recently published the results of numerous experiments of his own on the mill scale in Burmah, Bengal, Malabar, and Straits Settlements, and by Richmond in the laboratory of the Bureau of Science at Manila. Raitt finds in bamboo a really inexhaustible raw material. He
recommends the establishment of bamboo plantations so arranged that one-third of the whole plantation shall be cut over every year. This will secure absolute permanence of growth, and in fact such systematic cropping will increase production. Raitt finds the yields of bamboo to be II tons per acre where the growth was poor, 18 tons with moderate growth, and 44 tons per acre with luxuriant growth. The best yields of fiber 44 per cent, and the best results in treatment were secured with three-yearold shoots. The internodal pieces alone were digested, the rejected nodes amounting to 8 per cent of the total weight. The stems were cooked at 60 pounds pressure for 10 hours with 30 pounds of 76 per cent caustic per hundredweight of dry bamboo. The fiber bleached to good color with 20 pounds of bleach per hundredweight.
Raitt further finds that the stems were easily reduced by the sulphite process, giving a yield of 51 per cent, and bleaching to a brilliant white with 16 pounds to the hundredweight. He estimates that in a 200 ton sulphite plant at Rangoon the cost of bamboo fiber will be $24.30 a ton.
Richmond, whose excellent work in the Philippines deserves the highest credit, finds that it is quite unnecessary to remove the nodes prior to cooking provided the stems are first passed through crushing rolls and afterwards, for convenience of packing in the digester cut to 3 or 4-inch lengths. He obtains from the different varieties of bamboo yields of 40 to 43-7 per cent of bleached fiber by the soda process. The sulphite process gives 43.5 per cent bleached fiber, which puts bamboo on about the same basis as wood in this regard. The unbleached sulphite was nearly as white as the thoroughly bleached pulp.
The importance of these figures becomes evident when we consider that we have in bamboo a raw material directly comparable to wood in many respects, but with no bark to remove, and much more easily reduced to pulp by either the sulphite or soda process. Bamboo requires a weaker liquor and much less of it, and is reduced in less time with far less fuel consumption. A properly situated mill is assured of a regular supply with a yield per acre every third year greater than that resulting from the cutting over of well-grown spruce lands of good stand. Bamboo in fact has been known to grow 2 feet in three days in the Philippines. It is interesting to calculate from Raitt's figures for moderate growth that only about 16 square miles is required to maintain indefinitely the supply of bamboo for a 100-ton mill.
Two other raw materials for paper stock among those studied by Richmond demand special mention. These are Cogon Grass and Abacá or manila waste. Cogon Grass grows from 2 to 4 feet high in even stands on open lands, foothills, and mountains in the Philippines. In content of cellulose, as well as in general composition, Cogon closely resembles esparto and yields with equal ease to treatment. It gives a very fine, clean paper, stronger and with more snap than esparto. It does not, however, bulk as well, but for many uses should prove even more valuable.
The hand cleaning of manila fiber involves the production of much waste, while all of the several fiber stripping machines now on trial in the philippines produce waste in much larger proportion. For every ton of merchantable manila fiber produced in the Philippines, more than a ton of fibrous waste is made in the process of hand stripping, while nearly four times as much waste is now lost by the methods of machine stripping. This Abaca waste constitutes one of the most intrinsically valuable raw materials anywhere available for paper makers, and will not be treated as a waste much longer. Richmond and others have shown conclusively that the Abacá waste is very easily reduced by alkaline treatments, and further that it bleaches readily and is suitable for paper of the very highest grades. The more general introduction of fiber cleaning machines is certain to extend the manila hemp industry and to greatly increase the already large quantity of this waste available for treatment on the spot or for export. The yields of fiber on the hand stripped waste are about 42 per cent, and on the machine stripped one-quarter less.
It is obvious that the fibrous raw materials which we have been considering require somewhat different treatments to meet their individual requirements and that they are in most instances too bulky for profitable transportation. The natural line of their development is therefore the manufacture of pulp and halfstuff upon the spot for trans-shipment to the mills of paper-consuming countries. The methods required are for the most part simple and well adapted for introduction into small local plants.
For lack of time this report must pass by the numerous proposals made during the year for the utilization of other less promising fibers and fibrous wastes. Mention should, however, be made of Perini fiber (Canhamo Braziliensis Perini) recently discovered by Dr. V. A. de Perini of Rio de Janeiro, and now attracting considerable attention. In its essential features Perini resembles jute.
(To be continued.)
Metallic calcium is made in the electric furnace. More easily handled than sodium and less violent in its reaction, calcium makes a good reducing agent to purify molten metal at time of casting. Calcium is sold in little sticks, analyzing 96 to 98% in purity. It is nearly twice as light as aluminum. Its hardness is greater than that of sodium, lead, tin, and comparable with aluminum, somewhat less than zinc and magnesium. Its resistance to rupture is 0.61 kg. per square centimeter. It decomposes slowly in ordinary air, and very rapidly in air saturated with humidity, and burns with a very brilliant white flame. The most interesting combinations are those which it produces with hydrogen and nitrogen, calcium hydride (used in the preparation of gas for inflating balloons) and calcium nitride (suitable for purifying molten pig iron)..