Show THE manufacture OF ASPHALT oil and mining digest an english patent for a process for the manufacture manu facture of asphalt from petroleum residuum or from crude petroleum has recently been granted to mr chauncey B forward of urbana U S A it is well known that the oils produced in various fields throughout the world vary in gravity consistency and value according to the quantity and quality of the distillates derived for instance there are the so called paraffin base oils of ohio pennsylvania and other states or sections and the asphalt base oils of texas california and elsewhere as well known the patentee states that lie he has in a satisfactory way demonstrated that asphalt is in reality the base of all the so called paraffin fin base oils and he has made a superior grade of asphalt suitable fd for r paving roofing and insulating and in fact anything for which the natural asphalt can be used from this material in fact he has made these from almost every known oil field in the world and the product cannot be distin from natural asphalt by any meth or now known to the most scientific chemists in handling the crude oils or residuum in a commercial way ford for the production of asphalt the patentee first tries out a small quantity of residuum in an open vessel and subjects the same to a temperature of about degrees F the point to be observed being to keep it below the cooking point which destroys the value of the resultant product the lighter oil can be removed much more rapidly in an open vessel than in ia a retort or still the asphalt to be used for roofing or paving or insulating or as a base for paints and so forth are all of a different consistency and the patentee stops his process when the product in the open vessel has come to the desired consistency then he subjects it for a number of hours say five to twenty four hours to a temperature pera ture of about degrees F less than the temperature ture above specified the resultant product is then ready for the purposes desired there is practically no loss by exposure at the lower temperature as the lighter oils have all been previously removed he then weighs the product and determines the amount of volatile oils that have been driven off thus know ing the amount of volatile or lighter oils which he wishes to remove from a quantity of 0 crude oil or residuum to commence with ho he proceeds to make it in large quantities or on a commercial scale in the following manner the petroleum residuum is placed in a retort indicated by R in the accompany accompanying in g diagrammatic drawing it there be considerable sid erable moisture in the stock he subjects it to a temperature of about degrees F at this temperature the moisture will precipitate as water can be drawn off from the bottom of the retort through a suitable opening or pipe 4 for that purpose if however there is but a small amount of moisture present the temperature it sent up to or degrees F and in the course of an hour and a half to two hours at this temperature the moisture will all have been evaporated after all the moisture is driven off he increases the temperature to degrees F and continues to subject it to this heat for a period of twenty four to forty ei eight ht and up to sixty hours according to the gravity of the residuum originally started with the lower the gravity the 7 xa PR r FI UJ L J less time it will take to distill off the lighter products the exact time of subjecting it to the temperature of degrees F has to be determined ter mined in each instance by experiment with the of different gravities after the expiration of about thirty six to forty eight hours at this temperature he commences to test the resultant material in the retort by withdrawing a small quan kiy of it from time to time through a suitable opening at the top of the retort say as indicated at 5 and also check up at the same time the quantity of distillate which has been taken off then when the product has acquired the desired consistency according to the purpose for which it is being made up the fire is shut off and the material withdrawn to an open pan or vessel and allow it to be there subjected to a temperature of about degrees F less than it was in the still for a period of five to twenty four hours after delivering the material in an open vessel he subjected it to a temperature of about degrees F less than it was in the closed still and this chis heat is not sufficient to drive off any additional oils by vaporize oriza tion the exposure of the product in the cie open vessel at about this temperature has the effect of driving off some fixed gases but does not substantially lessen the material in weight and through this exposure the material acquired the black lustre or of the refined natural asphalt and an additional degree of hardness or toughness gh ness with its adhesive cohesive and lasting qualities which are lacking if the attempt be made to finish the material in the closed still |