US2014686A

US2014686A - Combustion of fuels

Info

Publication number: US2014686A
Application number: US629308D
Authority: US
Inventors: Lubovitch Eugene; Fieschi Jean Midor
Original assignee: LUBOVITCH
Current assignee: LUBOVITCH
Priority date: 1931-08-27
Filing date: 1932-08-18
Publication date: 1935-09-17
Anticipated expiration: 1952-09-17

Description

Patented Sept. .17, 1935 UNITED STATES PATENT OFFICE 2,o14,csc COMBUSTION .OF FUELS Eugene Lubovitch and Jean Midor Fieschi, Paris, France; said Fieschi assignor to said Lubovitch No Drawing. Application August 18, 1932, Serial No. 629,308. In France August 27 193 12 Claims.

In order to overcome these drawbacks it has been proposed to add to the fuel mixtures of different substances such as metal nitrates or 15 chlorates or the oxides of manganese, iron, chro- It has been found, however, that these substances when employed singly or in' the mixtures known so far have only a comparatively small influence on the combustion. Besides these 20 were mixed quite-unsystematically as the effect of the different substances was not recognized and consequently there havev been proposed some mixtures, which containedvup to ten different components. It is also unknown up to now that 5 mixtures of this kind were employed in shaft furnaces where the fuel is brought in direct contact with the material to be treated, undoubtedly because some 'of the chemicals commonly used for enhancing the combustion, like the sul- 30 phides or phosphates, would have, a detrimental influence upon the ore to be melted. We have found that the combustion process may be considerably improved by adding mixtures of substances belonging to certain groups 35 of substances which partly act as oxidizing catalysts, (i. e. substances which, without apparently losing their own oxide content to the fuel, nevertheless promote the absorption of the atmospheric oxygen by the fuel); partly as promoters 40 of the catalysts, (i. e. substances which, without containing themselves any oxygen, nevertheless seem to increase the catalytic action-of any oxidizing catalysts present); partly as immediate oxidizing agents or igniters (i. e. substances which 45 at the oven temperature yield their own oxygen to the fuel or the available atmospheric oxygen and by doing so directly accelerate the combustion of the fuel). The action of these combined mixtures exceeds by far the efiects which could 50 have been expected from-the known action of some of the individual components. The new compositions comprise as their main constituents: (1) Oxidesor salts of the rare earth metals or of metals having properties similar to those 55 of the rare earths, such as the. oxides or salts of cerium or thorium, in a form occurring in nature, e. g. in the form of mona'zite, which is a phosphate containing rare earths, or as an artificial product. Besides these substances the oxides of barium must be mentioned as especially potent- 5 oxidizing catalysts, whose use is equivalent to that of the oxides of rare earth metals.-

(2) An alkali chloride, such as potassium or sodium chloride, which presumably acts as a promoter.

(3) Furthermore, salts having an oxidizing action. These salts in being decomposed transfer their oxygen wholly or in part to the fuel and act as promoters of'the catalytical substances'or as igniters or as both promoters and igniters.

For instance, the nitrates or permanganates or chlorates of the alkali or alkaline earth metals may be used for such purpose. Different salts of this kind may be used simultaneously. Some of these substances may be regarded both as immediate oxidizing agents and as oxidizing catalysts, e. g. the alkali or alkaline earth permanganates.

To these main constituents of the new composition of matter, which represent the three abovementioned classes of substances, in the order named, other substances may, or may not be added, namely: h

(4) Compounds of metals which can form differentv degrees of oxidation, for instance the oxides or other derivatives of manganese, iron, 7

lead, copper, or mixtures thereof. All metal salts or oxides mentioned under 1 and 4 occur in different reversible degrees of oxidation. Their action which resembles that of strong catalysts, may be, explained in such a manner that the lower oxides are temporarily oxidized higher by the oxygen of the air conducted over or through the hearth or furnace, whereupon the oxygen set free again is transferred to the fuel in the nascent form, e. g. in an especially active form. In this way the metal compounds are retransformed into the loweroxidized state (or into the metallic state), and the whole process repeats itself continuously, associations and dissociations occurring simultaneously.

Instead of the compounds described above under (1) and (4), such compounds may be used, which at the temperature of the hearth or furnace form the oxides described and required.

The addition of merely a small amount of the new composition is sufficient for a considerable amount of fuel, because part of the reaction with the fuel to be consumed is not so much a chemical one in the ordinary sense, but a catalytic action, where a small amount of ingredients exerts and the like.

. metallurgical furnaces, etc.)

an indefinite eflect, without appreciably lessen ing the amount or changing the composition of the agents.

The presence of such a mixture facilitates the oxidation of the fuel. In consequence thereof the amount of air which up to now had to be supplied in excess to the hearth or furnace may be greatly diminished. The incandescent mass is no longer cooled by the-stream of superfluous air and the losses of calories in the waste gases are diminished.

' On the other hand the oxygen, taken up by the added composition from the air is given oil to the fuel in the nascent form. In that way the buming process is highly intensified and a higher temperature is reached in the glowing mass. For instance, the pressure in a steam boiler is raised' more rapidly by using coal with an addition according to our invention than with ordinary coal. Gaseous hydrocarbons are by this method burnt within the hearth or furnace instead of being drawn off u'nignited by the waste gases.

From the foregoing it becomes evident that a better localized, easier and more complete combustion is obtained with a minimum excess of air.

in this latter. The powdero may be added also in a suitable way in the preparation of briquettes, agglomerates and the like.

Example As an example, the mixture according to our invention may be composed as follows:

Per cent Cerium oxide 10 to Barium nitrate to Sodium chloride 40 to Onetotwokilogramsof this mixtureperton of the fuel are sufficient in order to obtain a far more complete cmnbustion with a minimum excess of air and to have the other advantages described above. J

The present invention is of special importance for use in shaft furnaces in which the materials to be treated are mixed with the fuel and in which the disadvantage of the coal being incompletely oxidized is especially great. The presence of the new composition has no detrimental influence whatever on the product of the furnace work since it does not contain any injurlous components such as sulfur, phosphorus,

m scope of applicability of our invention is large and extends over hearths for industrial and home use and different kinds of furnaces (rotary furnaces, so called Hofl'mann furnaces, (annular furnaces for roasting limestone and the like) It is furthermore suitable for every kind of natural or artificial solid, liquid or gaseous fuel.

We claim:

1. A process of improving the. combustion of solid fuels, comprising the addition to the fuel of a small amount of a mixture containing at least one alkali chloride, at least one substance selected from the oxides and salts of cerium and thorium and the oxides of barium and at least one salt selected from the nitrates, permanganates and chlorates of the alkali and alkaline earth metals.

2. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a small amount of a mixture containing at least one alkali chloride, at least one oxide of barium and at least one salt selected from the nitrates, permanganates and chlorates of the alkali and alkaline earth metals.

3. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a small amount of a mixture containing at least one alkali chloride, oxide of cerium and at least one salt selected from the nitrates, per- 15 manganates and chlorates of the alkali and alkaline earth metals.

4. A process of improving the combustion of a solid fuels, comprising the addition to the fuel,

of a small amount of a mixturecontaining at 20 least one alkali chloride, at least one substance selected from the salts of cerium and at least one salt selected from the nitrates, permanga-- nates and chlorates of the alkali and alkaline earth metals.

5. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a small amount of a mixture containing at least one alkali'chloride'at least one substance selected from the oxides and salts of cerium and 80 thorium and the oxides of barium and at least one salt, selected from the nitrates, permanganates and chlorates of the alkali and alkaline earth metals and at least one oxide of a metal which can form different degrees of oxidation, as selected from the compounds of manganese, iron, lead and copper.

6. A process of improving the combustion of solid fuels, comprising the addition to the fuel of a small amount of a mixture containing at 40 least one alkali chloride, at least one oxide of barium and at least one salt, selected from the nitrates, permanganates and chlorates of the alkali and alkaline earth metals and at least one oxide of a metal which can form different 45 degrees of oxidation,- selected from the compounds of manganese, iron, lead and copper. 1

7. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a small amount of a mixture containing at 5 least one alkali chloride, at least one substance, selected from the oxides and salts of cerium and thorium and at least one salt, selected from'the nitrates; permanganates and chlorates of the alkali and alkaline earth metals and at least 56 one oxide of a metal which can form different degrees of oxidation, selected from the compounds of manganese, iron, lead and copper.

8. A process of improving the combustion of solid fuels, comprising the addition to the fuel, soof a small amount of a mixture containing at least one alkali chloride, oxide of cerium and at least one salt, selected from the nitrates, per manganates and chlorates ofthe alkali and alkaline earth metals and at least one oxide of a 06 metal which can form different degrees of oxidation selected from the compounds of manganese, iron, lead and copper.

9. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a'small amount of-a mixture containing at least one alkali chloride, atleast one substance, selected'from the salts of cerium and at least, one salt, selected from the nitrates, permanganates and chlorates of the alkali and alkaline ll earth metals and at least one oxide of a metal which can form diflerent degrees of oxidation, selected from the compounds of manganese, iron, lead and copper.

10. A process of improving the combustion of solid fuels, comprising the addition to the fuel, of a small amount of a mixture containing at least one alkali chloride, at least one substance, selected from the salts of cerium, and at least one salt, selected from the nitrates, permanga nates and chlorates of the alkali and alkaline earth metals and at least one oxide of a metal which can form different degrees of oxidation, selected from the compounds of manganese, iron, leadand copper.

11. A process of improving the combustion of solid fuels, comprising the addition to the fuel,

of a small amount of a mixture containing at least one alkali chloride, monazite, and at least one salt selected from the nitrates, permanganates and chlorates of the alkali and alkaline earth metals.

12. A process of improving the combustion of solid fuels, compris n the addition to the fuel. of a'small amount of a mixture containing at least one alkali chloride, monazite, and at least one salt, selected'from the nitrates, permanga- 10 nates and chlorates of the alkali and alkaline earth metals and at least one oxide of a metal which can form different degrees of oxidation, selected from the oxides of manganese, iron, lead and coppe 15 EUGENE LUBOVI'I'CH. 'JEAN MIDOR FIESC'HI.