US621041A - Artificial fuel - Google Patents

Description

I UNITED STATES PATENT OFF CE.

J OI- IN T. DAVIS, OF SAN FRANCISCO, CALIFORNIA.

ARTIFICIAL FUEL.

SPECIFICATION forming part of Letters Patent N 0. 621,041, dated March 14, 1899. Application filed November 17, 1898. Serial NO- 696,715. (No specimens.)

To all whom it may concern.

Be it known that I, JOHN T. DAVIS, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Artificial Fuel, of which the following is a specification.

My invention relates to artificial .fuel 5 and its object is to utilize for that purpose waste products, such as culm and coal-dust or natural products of low combustible value, such as various grades and kinds of lignite. By combining with such products in proper proportions ingredients of higher combustible value I raise the combustibility of the agglomeration to the proper average and at the same time consolidate the inferior base which forms the greater part of the resulting mass into a firm substantial fuel in the form of briquets, Which will stand up in the fire and will be a cheap but efficient substitute for the higher grades of natural coal. Such a binding composition also forms a hard envelop which assists in retaining the Volatile gases generated by combustion, a great percentage of which pass away and are wasted in the ordinary use of low-grade fuel. For binding the low-grade material I use asphaltum, crude petroleum of heavy gravity, and bituminous coal. In referring to asphaltum I include any natural asphaltum and also manufactured asphaltum, ordinarily produced in different grades of hardness, as a residuum of the distillation of petroleum. Either or both substances can be used, according to the circumstances attending their supply, such as their relative cheapness or the'facilities for obtaining them. Under some circumstances I also use a pro portion of ozocerite on account of the inflammable nature of the paraffin which it contains. The proportions of my binding composition vary somewhat according to the na ture of the material which is to form the base of the ultimate fuel. Ordinarily they will be as follows: l/Vith from one hundred to one hundred and seventy-five pounds of asphaltum (natural asphaltum, manufactured asphaltum, or a mixture of both) I combine ten to twenty-fi ve pounds of crude petroleum and one hundred to one hundred and fifty pounds of bituminous coal, which should contain at 300 Fahrenheit.

least twenty per cent. of bitumen. The as phaltum (natural, manufactured, or combined) is melted in a proper vessel at a tem perature of 250? Fahrenheit or more. To it is added the crude petroleum to toughen the bitumen, and finally the pulverized bituminous coal to increase the quantity of bitumen. The combined ingredients are thoroughly mixed and incorporated and while hot are run into molds to form blocks of any shape convenient for transportation. Thus these blocks form a special article of manufacture which can be kept in stock for sale or transported for use elsewhere as a binder to be used with low-grade materials, such as those referred to.

When ozocerite is used, as before mentioned, its melting would form the first step in the process, since its'melting-point is above gredients would be added tothe ozocerite in the order before given and the blocks molded in the same way.

It is not necessary to mix the bituminous coal with the other ingredients of the binding composition at the time those ingredients are incorporated together. In many cases, and particularly where the binding composition is made for use and not for'sale or transporta tion, the bituminous coal can be added to the mixture at the time of its incorporation with the low-grade material. This would be the case ordinarily at a mine producing lignite, for instance, or at works where the preparation of the binder and its incorporation into the fuel are both carried on. In such cases the mixed asphaltum and oil would be melted and combined with the lowgrade base and the pulverized bituminous coal. The effect In such case the other in is the same as if the coal had originally formed a part of the binder.

When the coal originally forms a part of the binder, it is preferred to grind the blocks to a powder and mix it with the inferior ma terial, the latter being in small fragments or, in case of coal-dust or culm, in natural form. In either case heat is then applied-say 250 Fahrenheitso as to soften the binder and allow the combined mass to be molded into briquets, eggettes, or other forms convenient for use as fuel.

' into briquets; but when combined with this binder that difficulty is entirely overcome. Thus the binder, besides its primary object of increasing the combustible nature of the lowgrade base,a1so gives it the same quality of permanence that is found in high-grade natural coals. It is also to be observed that the noncoking bituminous coals, as well as the brown lignites, have in their composition from thirty to fifty per cent. of fixed carbon and from thirty-eight to forty-two per cent. of volatile gases. In the ordinary use of these coals, the volatile gases not being held in close affinity with the fixed carbon, much. of their value passes away without being utilized. This is due to the fact that the oxygen of the atmosphere is not brought into contact with them at such a temperature or in sufficient quantity to convert them into carbon dioxid. By the use of the binding composition they are restrained and held back until the combustion of the binding-envelop, which is necessarily ata temperature to convert the gases into heat units. This brings the heating qualities of the lignites up to a much higher standard than can be secured without the use of the binding composition.

In the utilization of lignites which contain sulfur I find it of advantage to incorporate with the binder a percentage of lime equal to the amount of sulfur present that is, the chemical equivalent-401' the purpose of preventing the escape of sulfurous-acid gas.

What I claim as new, and desire to secure by Letters Patent, is

1. A binder for low-grade material, such as lignite, culm and the like, composed of asphaltum, crude petroleum and bituminous coal.

2. An artificial fuel composed of a low-grade material such as lignite, culm and the like,- combined with a binding composition composed of asphaltum, crude petroleum and bituminous coal.

In testimony whereof I have affixed my signature, in presence of two witnesses, this lth day of November, 1898.

JOHN T. DAVIS.

\Viti1esses L. W. SEELY, H. J. LANG.