US1438542A - Process and apparatus for producing carbon black - Google Patents

Description

C. MATLOCK.

PROCESS AND APPARATUS FOR PRODUCING CARBON BLACK APPLICATION FILE D MAR, I4. 1921.

Patented Dec. 12, 1922.

glwoqnlio'o Ukawncey Mailocfi,

293, @a/zz%w Patented Dec. 12, 1922.

"umrrao 1,433,542 PATENT OFFICE,

CHAUNCEY MA'rLOoK; or BROOKLYN, NEWIYORK, ASSIGNOR T0 MONROE-LOUISIANA CARBON COMPANY, OF MONROE, LOUISIANA, A CORPORATION OF DELAWARE PROCESS AND.APPARATUS FOR- PRODUCING CARBON BLACK;

Application filed March 14, 1921. Serial NO. 452,291.

To all whomjt may concern:

Be it known that I, CHAUNCEY MATLOCK, a citizen of the United States, residing at 207 Park Place, Brooklyn, county of Kings, State of New York, have invented certain new and useful Improvements in Processes and Apparatus for Producing Carbon Black, of which I declare the following to be a full, clear, and exact description.

The presentinvention relates to the production of carbon black and more particularly to a process and apparatus for the production of carbon black by the partial combustion of hydrocarbon.

Carbon black has been customarily produced heretofore by burning natural gas or other gaseous hydrocarbons in a large number of small burners in such a manner that the outer part of the flame received sufficient air for complete combustion while the inner portion of the flame was subjected to a dissociating temperature and insufficient air for complete combustion. Through the dissociation and partial combustion of the hydrocarbons in the interior of the flame a small amount of free carbon, together withsome incompletely dissociated hydrocarbons was formed. This carbon was collected, and the further oxidation of the hydrocarbons and destruction of the carbons thus formed,

through the access of air through the upper I the carbon produced. These deposits of.

tarry matters were further decomposed on the chilled plates by continued heating and.

formed a denser carbon having a lower coloring power, lower orosity and being otherwise undesirable or many purposes.

An object of the present invention is to provide an efficient process of producing car bon black of high quality.

Another object of the present invention 15 to provide a process for the production of a carbon black free from deposits of moisture or other condensates or impurities.

W 1th these and other objects in view the lnvention consists in the process described in the following specification and defined in the claims.

The various features of the invention are lllustrated in the accompanying drawing whlch shows a view, partly in vertical section, of a preferred form of an apparatus for carrying on the present invention;

In the present invention the hydrocarbons which are to be used for the production of the carbon black are burned in comparatively large flames in which a complete and thorough mixture of air for the partial combustion of the hydrocarbons is permitted, and the degree of oxidation of the hydrocarbons is controlled by regulating the air supply and the temperature conditions throughout the flame to break up or dissoclate and partially oxidize all of the hydrocarbon and form a'maximum of free carbon particles. To this end a'regulated quantity of hydrocarbon gases is supplied to the lower part of a closed combustion chamber or furnace through a number of burners and is mixed with a regulated supply of air whlch is forced into the furnace below the burners by means of a blower or other air,

supply means. Upon passing upwardly in the furn ace the air and gas are mixed and lgmted and the hydrocarbons are dissociated and burned to form carbon and gaseous products of combustion. A body of hot products of combustion is preferably maintained in the furnace and the combustion of the hydrocarbons takes place within and surrounded by this body of hot products. of combustion, the air and hydrocarbons being thoroughly mixed and the complete combustion of the carbon produced being avoided by limiting the air supply to the minimum required to dissociate'the hydrocarbons and sustain combustion. Throughout the combustion the mixture of hydrocarbons and air is surrounded by hot gases and the combustion reaction is not efi'ected by contact with cold surfaces or in any other manner which would check the complete dissociation of the hydrocarbons.

As the burning gases reach the upper part of the combustion chamber the dissociation completed and the hot gases and suspended carbon are thereupon rapidly removed and quickly chilled to prevent any further heating, reoxi'dation or other modification of the carbon already formed. The chilling of the products of combustion and carbon 1s carried to a point at which the carbon may be separated from the gaseous products of combustion but the temperature of the chilled products is always maintained above the dew point of water and other condensable products in the gaseous products of combustion. The carbon is separated from the cooled products of combustion by means of bag filters or other suitable means, the temperature during this separation being of course maintained above the dew point.

Referring more particularly to the accompanying drawing, a regulated supply of gaseous hydrocarbons is admitted to a furnace 1 through a supply pipe 2 and a controlling valve 3 and is distributed throughout the lower part of the furnace by burners 4. A regulated supply of air suflicient to afi'ect only a partial combustion of the hydrocarbons is forced by means of a fan or blower 5 through'a supply condult 6 and controlling damper 7 into the furnace l at a short distance below the burners 4:.-

As the air passes upwardly into contact with the streams of hydrocarbon gases issuing from the burners 4. it is permitted to mix with the hydrocarbons and upon the completion of the mlxture the gases are burned in the furnace at a short distance above the'burners. A body or blanket 8 of hot ori ncandescent products of combustion is preferably maintalned in thefurn'ace extending upwardly from. ashort distance above the burners 4: and'the completion of the mixture of the gas and air and. the combustion of the hydrocarbons takes place in this body or blanket of hot gases. Through this manner of treatment the hydrocarbons are subjected in the body gases to a substantially uniform temperature throughout out of contact with cold surfaces or cold gases. The dissociation and combustion of the hy-' drocarbons is therefore, not affected through a local chilling or cooling of the Asthe gases reach the upper part. of the furnace the desired reaction-will have been completed and the gases are therefore quickly withdrawn through an outlet pipe 10 by means ofa' fan 12 and are forced ata high velocity through a cooling pipe 14.

The pipe'14is cooled by means of streams of water supplied from distributing or drip ipes 16 or by other suitable cooling means y which, .a moderate and uniform chilling of the pipe may be .attained. Through the rapid passage of the gases and carbon the filter they are freed from t the gases is produced, which taken in con 'nection with the velocity of the gases, hinders the settling and collection in the cooling pipe of deposits of carbon.

The temperature to which the gases are cooled is determined by means of a thermometer 18 in a pipe 20 leading from the cooling pipes 14 to a carbon separating. device 22. The temperature to which the gases are cooled is indicated by the thermometer and is regulated by controlling the quantity of gases entering the pipe 10 by adjusting the opening of a damper 24 in the pipe 10 and by controlling the quantity of water supplied through a control valve 26 to the distributing pipe 16. The temperature of the gases passing in contact with the thermometer 18 is adjusted so that it is slightly above the dew point for moisture and other condensable vapors produced in the combustion of the hydrocarbons and contained in the products of combustion.

The dew point for any particular case may of course be determined in the usual manner by cooling the gases to a point at which a deposit of dew or any condensable product is produced. In case the dew point produced in the combustion of any particular hydrocarbon is a' temperature above that at which the carbon may be conveniently separated from the gaseous products of combustion, it maybe lowered by admitting into the cooled, or partly cooled gases, a

sufiicient amount of air or other dry gas, care being taken, however, not tobring the air into'contact with the partly burned gases at a temperature high enough to bring. about a secondary combustion.

' The carbon may be separated from the cooled gaseous products of combustion by any sultable separating {apparatus but a bag filter of the type illustrated in the acends of which are fastened to openings 30 in a horizontal partition 32 dividing the separator 22; As the gases ass through c suspended particles of carbon and are withdrawn from the upper" part of the separator through an.

outlet pipe. 34, a fan 36 being preferably provlded' to create a suction and draw the gases through the filter bags. When a'de posit of carbon has been formed on the inner surface of thebagsto such an extent as to hinder the passage of gases therethrough the carbon vis detached from the bags by giving the upper part of the bags a circulatory movement. To this end the tops of the bags are supported by blocks 38 sus pended from a frame 44) which maybe os- 2130 cillated or given a circulatory movement by means of an eccentric shaft 42 and a crank 44. To assist in the removal of the deposits of carbon, chains 46 are suspended from blocks 38 and as the blocks are given a circulatory movement the chains are thrown against the sides of the bags and assist to detach the carbon. The carbon detached from the bags drops into a hopper 46, forming the lower part of the separator 22, and may be removed by withdrawing a slide 48 in an opening 50.

While only the preferred embodiment of the invention has been described in this specification, it will be apparent that the form and type of carbon separating device may be modified'and that other changes in the apparatus and modification of the processmay be made without departing from the broader features of the invention.

Having described the invention what is claimed as new is: Y

-1. A process of producing carbon black which comprises burning hydrocarbons with an amount of-air sufficient to form a substantial amount of free carbon from said hydrocarbon, maintaining a uniform mixture' of air and hydrocarbons and uniform temperature conditions throughout said burning, removing the products of combustion'and suspended carbon particles resulting from said combustion, cooling said gases I ture at which substantial amounts of tarry substances tend to form, removing said gas and suspended carbon particles resulting from said combustion, cooling said gases and carbon, filtering said suspended'c'arbon from said gases and maintaining said gases above the dew point-of condensable vapors in said gases during said treatment and said i filtering. '3. A process of producing carbon black which comprises burning a mixture of hydrocarbons with an amount of air-insuflicient to oxidize all of the carbon of said hydrof carbons, completing the partial combustion of said hydrocarbons out of contact with cooling surfaces, withdrawing theproducts ofeombustion and carbon from said furnace, cooling said products of combustion and carbon to a temperature above th? dew point of water vapor and condensable above the dew point of water and condens-' able vapors in said gases-filtering the carbon fromthe gaseous products of combustion and maintaining the temperature of said products of combustion above said dew point during the filtration of said carbon from said gaseous products of combustion.

5. A process of producing carbon black which comprises partially oxidizing hydrocarbons to form suspendedparticles of freev carbon, withdrawing said carbon suspended in the gaseous products of combustion, cooling said gases and said; carbon to a point somewhat above the dew point of condensable vapors in said gases and separating the,

carbon from the cooled gases. 1

6. A' process of roducing carbon black; which comprises ma'ntaining a body of hot products of combustion, introducing into said mass of products of combustion hydrocarbons and air in insuflicient quantitiesto completely oxidizesaid hydrocarbons, said air and hydrocarbons being in intimate contact, effecting the partial combustion of saidjhydrocarbons in said hot products of combustion, withdrawing the gases and carbon resulting from said combustion, cooling said products of combustion and carbon to a temperature above the dew point of con densable vapors in said products of combustion and separating said carbon from said gaseous products of combustion while maintaining the temperature ofv said products above said dew point.

i 7. A process of producing carbon black which comprises effecting the partial combustion of hydrocarbons in an atmosphere of hot products of'combustion, withdraw.- ing hot products of combustion and suspended carbon, cooling said products of combustion and carbon to a temperature but slightly above the dew pointlof said products of combustion and separating said carbon from the gaseous products of combustion while maintaining said products of combustion and carbon at a" temperature above said dew'point.

8. A process of producin carbon black which comprises burninghy rocarbons with tered or otherwise separated from the hot gases Without precipitating moisture or oils and separating said carbon from said gases 10 at said temperature.

In testimony-whereof I aflix my signature.

CHAUNCEY MATLOCK.

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