International Library of Technology: A Series of Textbooks for Persons Engaged in the Engineering Professions and Trades, Volume 22International Textbook Company, 1902 - Agriculture |
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International Library of Technology: A Series of Textbooks for ..., Volume 90 International Textbook Company No preview available - 2015 |
International Library of Technology: A Series of Textbooks for ..., Volume 90 International Textbook Company No preview available - 2015 |
Common terms and phrases
alloy amount amperes anode antimony arsenic assay base bullion blast furnace bottom carbon monoxide carried cathode cent charge chemical chlorine clay coal coke condensation conductor containing cool copper crucible crust crystals cupellation CuSO deposited desilverization desirable dioxide dissolved distillation effect electricity electrodes electrolyte ferrous filter fireclay flow flues fluxes forehearth fuel fused fusible galena gases gold hearth heat hyposulphite impurities inches iron jackets kettle leaching lead oxide lime limestone liquid litharge material matte mechanical melted metallic zinc method mixed mixture molds molten lead nace obtained operation pass percentage pipe plates possible pounds practice precipitate present produced proportion quantity reduced refining removed resistance retorts reverberatory furnace roasting separate shown in Fig silica skimmed slag smelters smelting sodium solution specific gravity sulphate sulphuric acid tank tap hole temperature tion treatment tuyeres usually volatilization weight zinc oxide zinc sulphide
Popular passages
Page 17 - ... to be standardized. In order to save time, a portion of the clear liquor is decanted from the precipitating vats / to the sump tank k. THE RUSSELL PROCESS 45. The Leaching Solution. — If ores containing much lead are treated with hyposulphite of calcium or sodium, a large proportion of the metal will be dissolved. If, at the same time, copper is present, the sulphides precipitated from the solution will contain silver, copper, and lead, a combination of metals not desirable for subsequent treatment....
Page 41 - Locality of Electrolysis. — The chemical changes directly produced by the current do not take place in the mass or body of the liquid, but at the submerged surfaces of the electrodes by which the current enters and leaves the solution, and are strictly limited to the extremely thin layers of metal and liquid in immediate contact with each other.
Page 41 - ... current do not take place in the mass or body of the liquid, but at the submerged surfaces of the electrodes by which the current enters and leaves the solution, and are strictly limited to the extremely thin layers of metal and liquid in immediate contact with each other. 75. Quality of Electrodeposited Metals. — The physical properties of the electrodeposited substances are largely affected by a number of circumstances, such as the temperature and composition of the electrolyte, the density...
Page 35 - Process. — Of all processes proposed for the treatment of lead-zinc sulphides, this one has attracted the widest attention. It gave great promise of success and an enormous sum of money was expended in establishing works in New South Wales. It has not up to the present time proved a success. On account of its prominence, it is of especial interest and the investigations done upon it have resulted in the accumulation of a large amount of valuable information. In outline, the process is as follows:...
Page 9 - ... importance, while still others are deleterious and may be regarded as impurities. 18. Lead-Silver Alloys. — Silver alloys with lead in all proportions, though there is a definite proportion, namely, about 650 ounces per ton, which is pointed to by some of its physical properties as an eutectic; that is, when it melts at a low temperature. Up to this proportion silver lowers the melting point of the alloy; beyond it, the melting point rises. The amount of silver left in lead after desilverization...
Page 36 - ... from which it follows that "the weights of elements separated in these electrolytes are to each other as their chemical equivalents ; " and that " the quantity of a body decomposed in a given time is proportional to the intensity of the current." On this is founded the use of Faraday's voltameter, in which the intensity of a current is ascertained from the quantity of water which is decomposed in a given time.* It would seem, then, reasoning a priori, that a constant multiplier obtained for a...
Page 21 - Each anode is inclosed in a muslin bag, that serves to catch the undissolved metals, which fall as a black slime. In this are found all the gold and bismuth, the greater part of the lead as peroxide, together with some silver and copper. Below this system of anodes, cathodes, and bags in the bath, is stretched on a box-like frame a piece of cloth, on which is gathered the deposited silver as it is scraped from the cathodes by wooden
Page 24 - The staves should be cut to the sweep of vat and 9 inches longer than the inside height, but not gained for the bottom, and the latter should be without dowel-pins and cut to a diameter 2 inches greater than that of the finished vat. The gaining of the staves, 1 inch deep, is done by hand, leaving a chime of 6 inches below the bottom.
Page 11 - The rapidity of smelting in the Bartlett furnace is governed by the silica, that is, in case zinc is high in the slag, the fuel is increased and the silica raised, thereby causing slower smelting and less zinc in the slag. Zinc left in the cinder is always in the form of sulphide. Silicate of zinc is not formed, but oxide of zinc may be absorbed to a large extent, especially in the basic-iron slags.
Page 42 - H,SO, is electrolyzed with zinc electrodes, no oxygen being liberated owing to the affinity of the oxygen for the zinc. The ions may be liberated in an abnormal state. Thus, oxygen is frequently liberated under proper conditions with a variation in its physical condition without change in its chemical condition, as ozone. Hydrogen may be liberated in its "nascent...