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T H E J O C R N A L OF I L V D U S T R I z 4 LA S D EYGI.YEERI.“\‘G CHEMISTRI’
The crude oleoresin, the “gemme,” as itiscalledin the “Landes,” exudes in the warm season (from March to October) from an incision made in the trunk. Kept open by the removal of a thin slice every week, this incision-the “cavve”-rises gradually up the trunk until it reaches, after five years’ working, a height of four yards or so. The tree is then left to recover for two or three years, after which time a fresh carve is made a t another point of the base. The tree is thus tapped for about forty years, after which it is “bled to death” (several cavres being worked simultaneously) heforc being felled for lumber purposes. In the “Landes” district strict arrangements arc carried out €or replanting the forest, s o that the resin production of the district is maintained. In the United States this conservative system has not been Collowed, i t having been the custom to tap the trees “ t o death” from the beginning, and every plot which was subjected t o tapping \vas practically destroyed after four years’ working, without any systematic steps being taken to ensure its re-establishment. Recently, however, this wholesale denudation has attracted public attention, and a better system of exploitation may be expected to result. From the top of the carre the drops of genznze, as they exude from the resin ducts of the tree, run down into a receiver. I n France, in former times, and in America, until quite recently, the receivcr was merely a hole hollowed out of the trunk a t the base of the c a m . The irrationality of this method has, however, been recognized, and the general procedure now is to hang a n earthenware or metal pot below the point where the resin is exuding. The contents of the pots are transferred about once a month into casks which, when filled, are taken to the distilleries. There the gemme undergoes two processes: first, a fusion for the separation of the oleoresin from the water and dirt; and, secondly, a distillation in presence of steam for the manufacture of the two commercial products, volatile oil of turpentine and non-volatile resin (rosin or colophony). The relative proportions of products of Bordeaux turpentine are 2 0 per cent. of oil, 7o per cent. of resin, and I O per cent. of water and dirt. Vezes has done much lrork toward improving the quality of the products, not only in connection with the distillation, but also in connection with the collection of the crude material. It is recognizcd that the resin, both crude and in the course of manufacture, is a substance extremely sensitive to the oxidizing action of air and sunlight. This action adversely affects both the color of the product and its physical properties. ilgreat improvement has been effected by reducing the period of exposure of the gemme during its stay in the incision, by raising the pot which receives the exudate a t frequent intervals, so that the path traversed in its flow is as far as possible restricted, and by collecting the contents of the ports more frequently. By these alterations both the loss by evaporation of the oil and the coloration of the resin by oxidation are materially reduced.
THE DISPOSITION OF WASTE SULPHITE LIQUORS Paper, Kovember 2 0 , 1912, p. 21, publishes some interesting correspondence pertaining to the utilization of thc waste liquors of sulfite cellulose mills which recently appeared in the Papier Zeztung. The subject was occasioned by the publication in the Frankjurter Zeztung of a paper in which the problem of the disposition of the waste liquors of industrial plants in general was touched upon; this paper, in which the question of waste sulfite liquor was referred to as particularly urgent, mas substantially as follows: The utilization or unobjectionable disposition of the waste lyes of i2dustrial plants has always been classed with the most important technical problems At present, this question has bccomc particularly pressing for cellulose plants working according to the sulfite process. The waste liquors of these establishments contain, in addition to sulfurous acid, about I O
Jan., 1913
per cent. of woodpulp in suspension which has been simply allom-ed to run off with the waste water. In consequence of the sulfurous acid, the lye is biologically detrimental to water courses, and has given rise to numerous complaints and claims for damages. In addition, the air in the vicinity of the mills has been badly contaminated. As a remedy, it was sought to utilize the waste liquors, useless for cellulose manufacturing, for other purposes, and, so far, two methods have been adopted. The process employed in Sweden is perhaps the most rational. Here the waste liquors arc used in the production of alcohol, being first treated with acid and a t the same time aerated to promote oxidation; the liquid is then neutralized, fermentation is started, and finally the alcohol produced is distilled off. This process is not economical in Germany. Recently, the idea of obtaining a solid product by the evaporation o f the liquor was proposed, and this is effected by a process patented by Trainer. A plant o n the Rhine is operating this process and produces from the waste lyes what is known as “Zellpech.” This product, when solid, is a transparent, resin-like substancc, containing about I I per cent. of water, ~~jper cent. of ash, and 36 per cent. of carbon; exposed to heat, it does not soften, but decomposes and finally burns ivithout smoke: it is pcrfectly soluble in water and the solution has adhesive properties. I t can be employed as a binder in coal or metal. briquetting, for which purpose it is said to have advantages over coal-tar pitch. At a plant in Bruckhausen, ISo,ooo tons of blast-furnace dust are said to be daily transformed into briquettes with thc aid of cellulose pitch. Finally, the lye, concentrated to a syrupy consistency, is an excellent medium for laying road dust. Ten kilos of lye, on evaporation, are said t o yield I kilogram of pitch, so that it is claimed a t least jo0,Ooo tons of pitch can be produced annually in Germany alone. To the preceding paper the Association of German Cellulosc Manufacturers sent a reply, which follows in abstract: “Where the waste liquors from cellulose plants are sufficiently diluted, biological damage in water-courses is not caused; it is only where mills are located on inadequate streams that such troubles have occurred. The ‘Zellpech’ plant in Rhineland has been able to utilize its waste liquor in making briquette material because it was financed and supported by capitalists n h o were particularly interested in securing an outlet for the coal and ore waste by the employment of the waste liquor as a binder. The geographical location of the Rhenish works is particularly favorable; the cellulose pitch can be marketed in mines in the immediate vicinity, so that transportation charges play hardly any part. The utilization of all the cellulose waste liquors produced in Germany for the production of pitch mould, moreover, be an impossibility, as the necessary outlet would be lacking. The idea of producing a solid product from spent sulfite cellulose liquor by evaporation is not of recent origin, and experiments in this direction date back many years.” In a later communication to the Papier Zeitung, a papermaker says: “The cellulose pitch, so enthusiastically praised in the Frankfurter Zeitung, contains 15 per cent. in place of about I O per cent of ash. The pitch is exceedingly hygroscopic and, in spite of its paper wrapping, must be stored dry, or it loses its crispness and deliquesces. I t must be finely ground for commercial briquetting. Damp, tough and no longer crisp the pitch causes trouble in the grinding, and, as the process of briquetting with hard cellulose pitch is patented, a license must be paid for its use. “For briquetting blast furnace charging dust, zellpech is used by but one furnace and the results are kept as secret as possible. Most furnaces find that they can briquet cheaper with the concentrated thick liquor and do not favor the use of the cellhlose pitch. “For coal dust briquetting the cellulose pitch is practically
una\,ailable becausc of its high percentage of ash. I t crumbles before burning and about t\vo-thirds of the heating value of thc briquette is lost in unconsumed substance in the ash. Shortly before his death, Trainer, who is freely quoted by the 1 ; m n k furter Zeitung, acknowledged that a good, combustible briqucttc could be made only with the aid of sulfite liquor freed from lime, a n opinion that can only be confirmed. “ I t is asserted that the coal briquettes made with thick spent liquor, gave no satisfactory results, even where rnadc insolublc in watcr by preliminary heating. “Attcmpts to use coke refuse or Ion-grade coal waste for hrique[ ting with sulfite liquors, would involve heavy financial risk. It is said that even the best anthracite coal docs not yield, ivith sulfite liquor, a commercially combustible. product. “That the briquettes arc smokeless and do riot softcnunderhcat, i h admittrd. and this may, in the future, provc a factor in coalbriquctting \vith lime-free lye. The wcathcrproof properties c l f the pitch praised in the Fra)ikfiirtsr %&tung arc of no conseiliience in relation t o its combustible properties. “Thc elimination of road dust has not so far heen veri- succcsslul, and if tar, so difficult of solution in water, is washed out in a comparatively short period, how much more quickly would the sticky, readily soluble sulfite liquor disappear. No large town can be named that, after the trials, has laid its road dust on a largc icalc \\ith spent sulfite liquors.” NEW PRESSURE FILTERS Hornett’s pressure filters arc being iiiatiufarturcd i i i s c \ c r a l forins, Jrith porous filter plates, for thc filtration o f liquids oi all kinds, especially acid and alkaline solutions. I t is clainirtl that they require hut one inan for the opwation o i iz filter capahlc of dealing with 150 cubic meters of liquid leaving 30 tons of residue,rand that in all cases the filtrate is clear. The construction of the vertical type A is the outside is shown in Fig. I . shell, or container, B is the filtering material, and C are filter plates. During filtration, A is hermetically closed and compressed air is forced i n ; the apparatus is not disturbed by air under high compression, and may be casily c1eaned:after the operation. The container is constructed of tin, lead, Fig I Lvood or clal-, enclosed in a shell of east iron or steel. The horizontal type is shoivn in Fig. 2 . U is the cover of the
E
C C
c
;‘A
1
L&2->
1 1
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FIG 2
container and A the filter shell-plates arranged in a horizontal position. Underneath -4, filter plates are placed in a position similar to that in the vertical filter. THE PURIFICATION OF WATER BY “ALLOPHANOIDS” Attention has already been directed to the purification of water b y means of artificial zeolites (THIS JOURN-XL, 4, N o . 4). The Deutsche Filtercompagnie, G. m. b. H. (French Patent 440,351, February 19, 1912) now claim that “allophanoids” (the siliceous, non-crystallizable portion of volcanic rocks) may be used instead of zeolites in the purification of water,
particularly for the eliniination of calciuni and Iiiagnesiuln salts. I t is said that “allophanoids” may be obtained by the elutriation of the powdered volcanic rocks by successivc portions of watcr, they being lighter than tlic crystalline portions c i f the rocks. ~ _ _ “ELECTRIT” “ISlcctrit” is an atirasivc made frorii aluiniiiuiii oxide by fusing i t in an electric furnace a t a temperature oi about 3,ooo” C . The .imevican M a c h i n i s t , 37, 24, states that its specific gravity is less than that of cmery and corundum, but its hardness is considerably higher, being about 9 . 2 5 on thc ioo sclcronicters scale. The grain ol “electrit” is almost aniorphous; it is resistant undcr prcssure and shock, and is tough and not brittle. “Electrit” grinding tvlieels arc bound ccraiiiically. arc said to be proof against moisture and acids, anti usable f o r \vet or dry grinding. THE UTILIZATION OF WASTE SODA LIQUORS 1 lic SociCtC Covziucrcz‘fcle des ( ‘ r z u s has a process for the iitilizatioii of Tvastc lycs xhich have been used in treating vcgctatilc fibers, especialll- cocoanut fiber, in the manufacture of hart1 and soft soaps. The waste lyes are filtered, then mixed with oils or fats in suitable proportions. I t is claimed that thc considerable amounts of dissolved resins present in the lye impart ccrtain desirable properties to the resulting soap. Owing t o the hcavy cost o f recovery, such lye is generally run t o wastc, 20 that the process presents thc advantage of economy. ,
