Show CYANIDE PROCESS about ten days ago says the denver min ing record we published a short editorial on the new cyanide process known as the pneumatic which was copied into so many papers and attracted so much notice that we have decided to biye a fuller description of this new process as a matter of general in interest ter to our readers the record has never dever hesitated to speak plainly against anything it deemed unworthy nor will it ever fail to commend anything of real value to the mining world when once thoroughly satisfied of its true merit As stated in our former editorial the good features of the pneumatic process are so more intimate contact and does in a few hours what it take days to do if the ore and solution remain unmoved in the leaching vats many attempts have been made to stir up or ao agitate irate the mass of leaching ore by machinery but the great cost of power expensive construction breakage break sige of parts etc has caused them to be aba abandoned and mill owners have gone bade back to the old slow process of letting the ore stand for days in the leaching vats because there was no practical and cheap way of agitating them or of getting the oxygen through the solution except by the slow alow absorption absOrb tion from the atmosphere just at this time when it seemed as if improvement improver nent in the cyanide process was at a standstill the pneumatic process comes forward with a method so simple and so effective that as we said before it is a wonder that it was not thought of sooner it is simply the introduction of strong currents of compressed air into the bottom of the leaching vats which force their way upward bubbling and boiling through tb rough the mass of crushed ores and cyanide solution and thus furnish both the oxygen and the agitation needed for the rapid and thorough gh extraction of th the gold egold this tile method of forcing the air through the leaching ores can be readily understood by means of the cuts herewith given all ai no ko I 1 shows a series of vets or tanks fil filled ledwith with and valves for the introduction and control bt bf the compressed air easily understood that it does docs not require an expert or a thorough clie chemist to to appreciate them for every mining man has had bad more or less experience with compressed air and most of them know some something thim about the cyanide process and understand that oxygen is absolutely necessary in a solution of cyanide of potassium in order to form a new compound called which is the true solvent of the gold they know also that agitation hastens the process of dissolving and extracting the values during the leaching process because a agitation or stirring enables the oxygen of the air to reach the solution more rapidly to and also to briar bring the ore and solution into no 3 is ig a view of the bottom of a leaching vat with a portion of the perforated false bottom cut away to show the coil of perforated air pipe by which the compressed air is evenly distributed over the entire bottom of the vat it can be readily seen f from rom these illustrations how fully the process solves the problem of leae leaching liing the ores rapidly and thoroughly requiring 11 only hours where old methods require days it also drives all the slimes to the surface where they cannot interfere with percolation as they do when permitted to settle at the bottom of the vats experience has proven that a hot solution of cyanide of potassium is more effective in f no 2 is a cross sect on cut through the middle of no 1 and shows the air pipes between the true and the perforated false bottoms of the vats and the trap door in the bottom tor for discharging te leached beached refuse dissolving gold than a cold one but until this process was invented no practical method of heating rows of large vats filled with wi solution an and d leaching ores was known now however by simply passing the compressed air through a small furnace before forcing it into the bottom of the vats the solution is heated the extraction hastened and increased and all danger of freezing in cold weather obviated an improvement which mill owners in high altitudes will certainly appreciate the method of precipitating the gold from the solution after the leaching pro cess is il COI completed is also a an n improved improvement ent over the present methods and is covered and protected by a separate patent it has all the good qualities of the old zinc box with the addition of three new features which aid in rapid precipitation and leave the solution in better condition for using a second time no 3 the inventor of the process has been working quietly for nearly three years in perfecting in it and securing his foreign patents but it has been before the public for less than three weeks the reception it has met from mining me men D familiar with the ordinary cyanide process must certainly be a source of pride to him for we believe that we can safely ely say that no improvement in metallurgy has ever been so quickly recognized or so warmly received by the mining world |