US2122764A - Production of blown asphalt - Google Patents

Description

July 5, 1938. J. s. WALLIS ET AL PRODUCTION OF BLOWN ASPHALT Filed Jan. 31, 1950 INVENTORS J \444; i

aka; 4,} 1 #vrATToRNEY than 20 Baum.

Patented July 5, 1938 PATENT OFFICE PRODUCTION OF BLOWN ASPHALT John Samuel Wallis, New York, and Harry R. Swanson, White Plains, N. Y., assignors to Foster Wheeler Corporation, New York, N. Y., a corporation of New York Application January 31, 1930, Serial No. 424,918

8 Claims. (01. 196-74) Our invention relates to treatment of hydrocarbon for the production of asphalt.

The practice in the past in treating heavy hyrdrocarbons for the production of asphalt has been to treat hydrocarbons in a suitable process as a result of which a component derived will be suitable for further treatment to produce asphalt. This asphalt component, or we might say, the residual flux oil from crude distillation, is then conducted to a horizontal cylindrical member which we may term a still, but which is hollow inside and without any internal constructions for flow of liquids so that the liquid all exists in one body as a large pool in such horizontal still. This liquid is then treated by blowing into it an oxidizing material such as air or superheated steam, and after this process has gone on for a while, the supply of air or superheated steam is shut off and the batch is withdrawn and another batch introduced. We may term this a batch process.

Indistinction to the batch process, we propose a continuous process for the production of blown asphalt, and to that end we propose to utilize a different type of structure in which a different process takes place. The structure may be of various forms and may be described by saying that it is similar to a fractionating tower. The purpose of using a tower similar to a fractionating tower is to obtain continuous flow of the hydrocarbon liquid downwardly overv a series of trays and to have continuous upflow of the oxidizing gas in contact intermittently with liquid bodies of the hydrocarbon.

As a further feature of our novel process, we utilize the heat developed due to the exothermic character of the reaction to carry on the process. The hydrocarbon used for this purpose is a hydrocarbon of high secifiv gravity, for example, greater The supply of oxidizing fluid is regulated in such a manner as to give a temperature such that the process takes place below the vaporizing point of the hydrocarbon, but above the point wher reaction begins to take place so that the p cess is one of reaction as distinguished from the mere formation of a physical mixture as by absorption.

The invention will become apparent and the nature and advantages thereof will be readily understood by reference to the following specification which describes the process, in conjunction with the diagrammatic showing of an apparatus on the accompanying drawing, it being drawing is for illustrated purposes only in an aid to understanding the invention.

Referring to the drawing:

Reference character designates a heater comprising tubes ll through which the hydrocarbon may be passed for the purpose of its .being heated. This is on the assumption that the process begins with a cold hydrocarbon. The hydrocarbon is passed through the pipe [2 and pipe l3 and enters the tower 14. Tower II contains a series of bubble trays l5 which may be of any various known constructions. The oil is shown as introduced on the top tray, but may be introduced at various points in the tower. The oil cascades downwardly from tray to tray in the tower in known manner.

Reference character i6 designates a separately fired heater containing tubes il in which the oxidizing fluid is heated. The oxidizing fluid may be air or steam. The oxidizing fluid enters through the pipe l8, passes through the separately fired heater and through pipe l9 into the lower part of the tower, where it may be introduced through a perforated pipe arrangement 20.

The oxidizing gas passes upwardly through the tower and successively through the ports of the bubble, trays, thus flowing in intimate contact with the continuously downwardly cascading hydrocarbon.

If the temperature is too low in the tower, reaction will not take place. Our process contemplates the existence in the tower of so high a temperature that reaction takes place and the oxygen chemically unites with the hydrocarbon as distinguished from mere absorption. Furthermore, the temperature must not be so high that the hydrocarbon vaporizes to any material extent since the purpose of the process is to maintain the hydrocarbon of suitable constituency to produce desired quality of asphalt. Consequently, we maintain the temperature between the limits indicated, which may be, for example, between 300 degrees Fahrenheitand 700 degrees Fahrenheit, depending upon the nature of the hydrocarbon used.

Gases, principally non-condensible gases derived from the oxidizing medium, are removed from the top of the tower through pipe 2| and pass to a cooler 9 in which any condensible gases may be liquefied.

The finished product is withdrawn from the bottom of the tower through the pipe 23 and passes through a heat exchanger 24 and to a point of storage. The incoming hydrocarbon may be pumped by a pump 25 through the heat exchanger 24 and thence to the tubes ll of the heater.

great extent upon the nature of the fluids used. To illustrate, in event that the hydrocarbon is received from the previous distillation process, it may be necessary to cool the hydrocarbon rather than to heat it, and in such case the heater l0 may be replaced by a cooler. Also, the temperature of the oxidizing gas is important, and

in order to obtain a regulation of this factor we provide a by-pass pipe 22 around the heater I6.

The nature of our process, within the limits of temperature indicated, is such that the reaction is exothermic, and we utilize the heat internally developed to maintain the temperature. Assuming that the oil has first been heated in a heater Ill, the temperature will rise in the tower to the point where it is necessary to diminish the heating. Also, we provide a by-pass 21 around the heater and the process may go on in such manner that no heat is supplied, the exothermic heat supplying all the heat that is necessary. Suitable valves are obviously provided to take care of the flow through the various pipes so that when, for example, the by-pass 21 is being used, flow is cut off through the heater Ill. Obviously, the flow may be proportioned as between the by-pass pipe and the heater I0.

We may further control the process by inserting a temperature-regulating coil at one or more points in the tower as indicated at 28. We may control the flow of a cooling fluid or a heating fluid through such cooling coil in order to maintain the temperature within desired limits. Obviously, it is possible toautomatically control the flow of cooling fluid, such as water, through the cooling coil 28 in response to temperature at one or a number of points in the tower so as to maintain a desired temperature automatically. To illustrate this, we have indicated diagrammatically a temperature-responsive element 29 within the tower as controlling a valve 30 regulating the flow offluid through the coil 28.

Obviously, the quality of the product obtained can be governed by the relative proportions of hydrocarbon and oxidizing fluid supplied to the tower. Furthermore, this may be regulated by adjusting the flow on the trays. For a higher degree of oxidation, either the time of flow of the hydrocarbon through the tower may be extended over a greater period of time or the amount of oxidizing fluid may be increased to give the desired product.

We prefer to carry out our process at substantially atmospheric pressure and regulate the product by control of the temperature. It is obviously possible, however, to-vary the pressure within the tower, and variations of pressure will effect temperature values in manner depending upon known laws of fluids.

It will be seen from the above that we may term the inside of the tower a reaction zone.

What we claim is:

1. The process of oxidizing an asphalt component of a hydrocarbon fluid for the production of blown asphalt which consists in continuously cascading the asphalt component downwardly through a reaction zone, continuously passing an oxidizing gas upwardly through the reaction zone in intermittent and direct contact with the downwardly cascading asphalt component to thereby oxidize the asphalt component and regulating the temperature at an intermediate point in the reaction zone to maintain thetemperature within limits below temperature of substantial vaporization of the asphalt component and suificiently It will be seen that the process depends to a I high to eiiect chemical reaction between the asphalt component and the oxidizing gas.

2. The process of oxidizing an asphalt compooxidize the asphalt component and automatically regulating the temperature at an intermediate point in the reaction zone to maintain the temperature within limits below temperature of substantial vaporization of the asphalt component and sufficiently high to eifect chemical reaction between the asphalt component and the oxidizing gas.

3. The process of oxidizing an asphalt component of a hydrocarbon fluid for the production of blown asphalt which consists in continuously cascading the asphalt component downwardly through a reaction zone, continuously passing an oxidizing gas upwardly through the reaction zone in intermittent and direct contact with the downwardly cascading asphalt component to thereby oxidize the asphalt component, utilizing the heat produced in the reaction zone as a result of the oxidation for carrying on the process and regulating the temperature at an intermediate point in the reaction zone to maintain the temperature within limits below temperature of substantial vaporization of the asphalt component and sumciently high to eifect chemical reaction between the asphalt component and the oxidizing gas.

4. The process of oxidizing an asphalt component of a hydrocarbon fluid for the production of blown asphalt which consists in continuously cascading the asphalt component downwardly through a reaction zone, continuously passing an oxidizing gas upwardly through the reaction zone in intermittent and direct contact with the downwardly cascading asphalt component to thereby oxidize the asphalt component, utilizing the heat produced in the reaction zone as a result of the oxidation for carrying on the process and automatically regulating the temperature at an intermediate point in the reaction zone to maintain the temperature within limits below the temperature of substantial vaporization of the asphalt component arid sufliciently high to eflect chemical reaction between the asphalt component and the oxidizing gas.

5. The process of oxidizing an asphalt component of a hydrocarbon fluid for the production of blown asphalt which consists in continuously cascading the asphalt component downwardly over bubble trays in a tower, continuously passing an oxidizing gas upwardly through said towerin direct contact with the downwardly cascading asphalt component to thereby oxidize the asphalt component and regulating the temperature at an intermediate point in the tower between bubble trays to maintain the temperature within limits below temperature of substantial vaporization of the asphalt component and sufliciently high to effect chemical reaction between the asphalt component and the oxidizing gas.

6. The process of oxidizing an asphalt component of a hydrocarbon fluid for the production of blown asphalt which consists in continuously cascading the asphalt component downwardly over bubble trays in a tower, continuously passing an oxidizing gas upwardly through said tower in direct contact with the downwardly cascading asphalt component to thereby oxidize the asphalt component, utilizing the heat produced in the tower as a result of the oxidation for carrying on the process and regulating thetemperature at an intermediate point in the tower between bubble traysto maintain the temperature within limits below temperature of substantial vaporization of the asphalt component and suiliciently high to effect chemical reaction between the asphalt component and the oxidizing gas.

7. Apparatus for treating an asphalt component of a hydrocarbon fluid to produce blown asphalt comprising a tower, bubble trays in said tower, means for supplying asphalt component to 'said tower to cascade downwardly over the bubble trays, means for regulating the tempera ture of the asphalt component comprising a first heater and a by-pass around said heater, means for supplying a gaseous oxidizing agent to said tower to flow upwardly in direct contact with the downwardlycascading asphalt component, means for regulating the temperature of the gaseous oxidizing agent comprising a second heater and a by-pass around said second heater, a conduit in said t wer between bubble trays.

conduit and means responsive to temperature between bubble trays in said tower for regulating flow or cooling medium through said conduit.

8. Apparatus for treating an asphalt component of a hydrocarbon fluid to produce blown asphalt comprising a tower, bubble trays in said tower, means for supplying asphalt component to said tower to cascade downwardly over the bubble trays, means for regulating the temperature of the asphalt component comprising a first heater and a by-pass around said heater, means for supplying a gaseous oxidizing agent to said tower to flow upwardly in direct contact with the downwardly cascading asphalt component, means for regulating the temperature of the gaseous oxidizing agent comprising a second heater and a by-pass around said second heater, cooling means in the intermediate portion of said tower and means responsive to temperature in the intermediate portion 01 said tower for controlling said cooling means.

0 JOHN SAIMUEL WALLIS. HARRY R. SWANSON.

, means for supplying a cooling medium to said

Images