INDUSTRIAL A N D ENGINEERING CHEiUISTRY
1286
Italian Letter
Paris Letter
By Carlo Padovani
By Charles Lormand
BOLOGNA, ITALY
4 AVENUSDE L’OBSERVATOIRE, PARIS,FRANCE
THEGEOTHERMICLPOWER STATION OF I,ARDERELLO A t the World Power Conference which was held in Wembley, the last of July, by the British Electrical and Allied Manufacturers Association, Prince Ginori-Conti read a very interesting communication on the Geothermic Power Central Station of Larderello. The country of Larderello, in Tuscany, has long been known for its celebrated soBoni-that is, natural hot springs or geysers, from which steam containing a small amount of boric acid issues. The boric acid in the sofioni was first discovered in 1777, and the production of boric acid was begun in 1815. Boric acid was a t that time crystallized from the small natural marshes, or lagoni, by artificial heating, and the fuel con$umption for evaporating purposes was considerable. Under the direction of Counts of Larderel, proprietors of the country and builders of this industry, the boric acid extraction made great progress. Artificial heat was entirely replaced by natural heat, and the boric acid was crystallized by conducting the hot vapors of the sojtoni,which had no other use, under the evaporating pans. At the same time the technic of boring and canalizing vapors was greatly developed, and the properties and constitution of natural gases and the production of several byproducts were carefully studied with the assistance of Prof. R. Nasini, of the University of Pisa. Thus the boric acid extraction industry of Larderello, which was a t first very primitive, became a sort of model industry, a truly self-controlled industry, which burned not one kilogram of coal or wood. But it was not until the beginning of this century that Prince Ginori-Conti, the president of the SocietA Soffioni Boraciferi di Larderello, undertook to study the utilization of natural steam for electrical power production. The solution of this problem offered great difficulties, but now, after twenty years of research, it has been accomplished. The first attempts a t natural power utilization in Larderello were made in 1904. Other successful experiments were made in 1905 (20 horsepower for illuminating purposes) and in 1912 (Fabbrica del Lago, 250 kilowatts, 250 kilowatts with turbines). Finally, in 1914 work at the central station a t Larderello with three turbo-alternators, each furnishing a motor power of 2500 kilowatts, was commenced. The steam as it comes from the earth is not directly available for the turbines, owing to its high gas content (HzS, COZ,He, etc.), and its low pressure (2 atmospheres). The steam producers indirectly he Led with natural hot vapors did not give good results. Now th? steam is freed of the gases in special apparatus invented by P. ,righenti. The pure steam a t a pressure of 1.5 atmospheres goes into the turbines a t 1.25 atmospheres. The turbines are of a modern type, with 3000 turns, and are joined to an alternator of 400 volts, 50 cycles. The steam already atilized is but a small proportion of that available. By increasing the number of borings it has been possible to obtain 150,000 kg. of vapor per hour. New borings gave steam a t higher pressures; a bore a t Serrazzano gives 24,000 kg. of steam per hour at 2 atmospheres, or 13,000 kg. a t 5 atmospheres; another boring a t Castelnuovo gives 60,000 kg. per hour a t 2 atmospheres. At Serrazzano a turbine has recently been tried which makes use of exhaust gases for heating the evaporating pans. The Geothermic Power Central Station of Larderello is capable of large development, and is, perhaps, the only example in the world of a great industrial utilization of volcanic power; and it shows a truly fascinating result of modern collaboration between science and industry. Prince Ginori-Conti believes that the utilization of volcanic vapors for generation of electricity could be successfully extended to the other volcanic regions in Italy, such as Pozzuoli, Etna, Stromboli, Vulcano, as well as in various other parts of the world.
3
October 10, 1924
Regulations Governing the Duty-Free Importation of Industrial Chemicals into the Dutch East Indies-The collector of customs of Java has issued rules of procedure which must be followed in order to obtain benefit of the duty-free admission of chemicals imported into the Dutch East Indies for industrial purposes, provided under the royal decree of March 17, 1923. These regulations have been forwarded to the Bureau of Foreign and Domestic Commerce, Department of Commerce, and information will be furnished upon request to the Division of Foreign Tariffs.
Vol. 16, No. 12
FUEL CONGRESS MEETS
A small congress for the study of fuels was held in Paris the first of October. Few contributions to this field were made which had not already been given to the congress of 1922. Although it is certain that the Maihle process, which consists of hydrogenating vegetable or fish oils, can give a theoretical solution of the fuel problem, it is no less true that this process does not permit obtaining fuel a t a price that can compete with the natural fuel. A ton of oil gives 98 kg. of glycerol and 902 kg. of fatty acids. From these fatty acids 630 kg. of petrol can be obtained. The value of the glycerol is about 500 francs; that of petrol, after fractionation into petrol, heavy oils, and lubricating oils, is about 1200 francs. After adding to this the cost of manufacture, estimated a t about 100 francs, one has a total of about 1800 francs. It would therefore be necessary for a ton of oil to sell a t a price less than 1800 francs-for example, 1500 francs; but actually, a ton of oil is worth about 3000 francs, which renders the process impracticable. The study of yields using chlorophyll is not yet sufficiently advanced for one to judge the economic value of the process. AS for the Bergius process, the problem seems to be advanced to the extent that it is now possible to treat, by berginization, bitumens, tars, asphalts, and in general all the liquid products; but berginization of coal is not yet perfected. In connection with this meeting considerable has been said in the press concerning the Bourgeois and Olivier process. This process uses the water gas furnished by the coke furnaces and, by a series of catalysts, passes successively through the first members of the hydrocarbons series-that is, methane, ethylene, and acetylene-and through successive polymerizations produces a synthetic oil having a calorific power of 11,539 calories per kilogram. Although it was stated that this process is already in the semiindustrial stage, the absence of details concerning its application causes a certain skepticism, inasmuch as, in the scheme of the process, there is nothing which was not already known in 1858, when Berthelot described these reactions. It was announced a t this congress that synthetic methanol is being made on an industrial scale in Germany. Under these conditions the wood carbonization industry, which was quite flourishing in France, will meet with severe competition. The production of wood charcoal will suffer by this, although its use for gas generators should be extended; since these generators have been on the market, wood charcoal has doubled in price. Along the same line, MM. Oswald and Penta have continued their researches on the solution of coal by means of naphthalene. By working a t temperatures around 270’ C., under a slight pressure, they have obtained extracts of coal containing neither sulfur nor ash, and by heating these extracts a t low temperature oils and tars containing considerable oil and little phenol are obtained. On carbonization these extracts give a coke without ash which is suitable for the metallurgical industry and the production of electrolytic carbon. Finally, and this is perhaps the most interesting point, these naphthalene extracts of coal containing no ash can be used directly in combustion engines using either solid pulverized products, or liquids similar to mazout. There are now under way numerous investigations to find an engine with a catalyst-that is, an engine in which a very heavy fuel can be transformed, in the same engine, into a lighter product. The solution of this problem seems to have been realized in the Mikhniof process, which the French navy has just adopted and which we know is already’in use in the United States. PREPARATION O F HYDROCARBONS M. Bourguel has studied a general method for the preparation of true acetylene hydrocarbons. He starts with true acetylene (C,,-) and passes to the higher product in the following manner: True acetylene is combined with soda in the form of sodium amide, then methylated by the action of dimethyl sulfate on the sodium compound obtained; a disubstituted hydrocarbon (Cs + I), which is isomerized by means of sodium amide is obtained. An identical operation applied to this C, + 1 hydrocarbon produces a Cn+ 2 hydrocarbon. Starting with true cyclohexylpropine, by five successive transformations M. Bourguel obtained the true cyclohexylhexine. This method should give very interesting results when applied, as M. Bourguel hopes to do, in the benzene, toluene, and napthalene series.
