US1709302A - Treating hydrocarbon oils - Google Patents

Description

April 1929. o. BEHIMER TREATING HYDROCARBON OILS Filed Aug. 11, 1925 CUNDENSER Baz amvemto'c 1? A); Elwyn w Patente'd Apr. 16, 1929.

UNITED STATES PATENT OFFICE.

OTTO BEHIMER, OF PORT ARTHUR, TEXAS, ASSIGNOR, IBY MESNE ASSIGNMENTS, TO THE TEXAS COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

TREATING HYDROOARIBON OILS.

Application filed August 11, 1925.

This invention relates to apparatus for treating hydrocarbon oils.

One of the objects of my invention is to provide means for pumping hot oil and for maintaining the pumping means in effective operating condition by maintaining the pump piston and packing relatively cool. In one of its more specific aspects my invention contemplates the use of a pump for pumping hot liquids and the provision of means for maintaining the liquid in the pump at a relatively low temperature. Still more specifically my invention provides means for introducing a cooling medium into the pump for overcoming any increase of temperature of the oil, which is'or may be caused by convection of heat from the hot condensate, or otherwise.

As a still further feature of my invention, I have provided a pump constructed with a surge line interposed between the valve chamber and the piston cylinder for handling hot oils, which comprises a valve casing or chamber and a pump cylinder separated from the valve casing by a column or columns of oil, and means for positively introducing into the column of oil a cooling medium, such for example, as fresh charging stock, for maintaining the liquid columns at a relatively low temperature.

My invention further contemplates the provision of means on the. surge line adjacent the valve casing for preventing any material loss of heat through radiation.

Other objects, features and advantages of my invention will appear as the detailed description thereof proceeds.

The illustrated example of my invention shows a pump for handling hot reflux or condensate from a condenser or dephlegmator. In carrying on the decomposition or cracking of hydrocarbon oils it is sometimes sought to subject the generated vapors to a condensing or fractionating or dephlegmating operation for the purpose of separatmg the heavier insufficiently converted products from the lighter products, such as gasoline, and return the heavier products while still i in a heated condition to the cracking zone for retreatment. Difiiculty has been experienced in pumping the hot reflux or backtrap due to the fact that gas sometimes accumulates in the lines of the pump so as to inter Serial No. 49,503.

fere with its operation and the liquid in the pump connections and cylinder frequently becomes overheated. In the practice of my invention a surge pump is employed to handle the hot reflux or backtrap'and a relatively cool oil, such as fresh charging stock, is introduced when necessary into the surge lines so as to displace gas accumulated therein and 7 so as to reduce the temperature of the liquid in,the surge lines and thus protect the pump mechanism from excessive heat. The introduction of the fresh charging stock has the further advantage that since this oil is ordinarily of a greater viscosity than the reflux condensate being int'roducedby the surge pump.it is thus possible to maintain in the surge lines and in contact with the moving elements of the pump mechanism an oil of better lubricating qualities than the reflux condensate being pumped back to the crackmg zone.

In Figure 1, I have shown diagrammatically a representative apparatus for treating hydrocarbon oil, wherein my invention is employed.

Figure 2 is a diagrammatic plan view, somewhat enlarged, of a part of the apparatus shown in Figure 1, while Figure 3 is a view in elevation of one of the valve casings shown diagrammatically'in Figure 2, a portion of the casing having been broken away to show the details of the valve structure.

Figure 4 is an enlarged view in elevation of a portion of the surge line.

Referring to the drawing, and for the present more particularly to Figure 1, a charging pump 10 isshown having a connection leading to a source of oil supply. The discharge side of the pump connects with a charging line 11 which leads to a heating coil 12 in a furnace 13. The furnace 13 may be heated by meansof oil or gas burners, or otherwise, and the waste heat may, if desired, be passed to an economizer (not shown) to preliminarily heat the charging oil passing therethrough. The oil in transit through the heating coil 12, may, if desired, be heated to a cracking temperature. The heated oil is passed through a valved pipe 14 and is discharged into a still 15, the still being positioned within a furnace 16 and maintained at a cracking temperature and pressure. If desired, the still may be insulated to prevent loss of heat and all of the heat required for the cracking operation supplied in the heating coils.

The vaporous products of decomposition and distillation are drawn from the still 15 through a valved vapor line 17 and are introduced into ,a fractionating tower 18 wherein a separation of the high and low boiling fractions is efi ected. The vapors and gases remaining after the separation are passed through a pipe 19 to a condenser box 20, the ultimate distillate passing from the condensate box 20 to a receiving drum 21. The drum is provided with a valved gas outlet 22 and a valved liquid outlet 23.

The still is provided with a valved drawotl' line 24 which may, if desired, lead to a heat exchanger (not shown) for preliminarily heating the oil pumped through the charging line 11.

The fractionating tower 18 is provided with a valved draw-off line 25 which leads to and connects with a manifold 26 having branches 27 connecting with the inlet or suction sections of valve casings 28 of a surge pump indicated generally by the numeral 29. The outlet or discharge connections of the several valve casings 28 are each connected by a line or pipe 30 to a manifold 31 connecting with a backtrap line 32 which connects with the charging line 11 and through which the backtrap from the fractionating tower 18, while still hot, is pumped into heating coil 12 for further treatment.

Each valve casing 28 is connected to one end of a surge line 33, the opposite ends of all of the surge lines being connected with theliquid end 34 of a steam pump indicated generally by the numeral 35. The steam end of the pump is indicated at 36, and a piston 37 reciprocates in the liquid end 34 to produce a surge of the liquid in the lines 33.

As shown in Figure 4, the surge line 33 is formed with an inclined portion, the water jacketed portion of the line being at a lower level than the insulated portion. Thus, there is little tendency for the hot oil in the insulated section, which naturally tends to rise, to mix with the cool oil in the lower water jacketed section, and accordingly there is a decided conservation ofheat in the hot oil which effects a real economy in operation.

A. pipe 38 is connected at one end to the charging line 11 at a convenient point intermediate the pump 10 and heating coil 12, the pipe being provided with a valve 39. The opposite end of the pipe 38 may be connected to one of the surge lines 33 and a branch pipe 40, controlled by a valve 41, may connect the pipe 38 with the other surge line 33 so that it at any time during the operation of the pump there is an accumulation of gas or light oil in the surge lines or the fluid becomes excessively hot, or in danger of becoming too hot, the valve or valves 39 or 41 may be opened a greater or less extent to permit any desired quantity of the charging oil, prior to its being heated, to be pumped into either or both of the surge lines. Thus it is a simple matter to control and regulate the temperature and character of the oil in the surge lines 33 and by maintaining the oil at a relatively low temperature the pump packing is not subjected to undue heat, as it otherwise would be, and the life of the packing is thus prolonged and the operating efficiency of the surge pump is increased accordingly.

The surge lines 33 are covered with suitable heat insulating material, as indicated at 42, at the ends connecting with the valve casing. The insulating material extends only throughout a portion of the length of the surge lines and prevents loss of heat from the hot fluid from the valve casing as the fluid-is drawn into the surge line on the suction stroke of the surge pump. The opposite end of the surge 1ine,--the end adjacent the steam pump 35,-is water acketed as at 43 to maintain the fluid in that end of the surge line relatively cool so that the fluid drawn into the fluid end 34 of the pump will not impair the pump packing.

The valve casings 28 are each provided with a lower passageway 44 connecting with the pipe 27, an upper passageway 46 connecting with the pipe 30, and an intermediate passageway connecting with one of the surge lines 33. A port 47 is provided between the lower and intermediate passageways 44 and 45, the port being provided with a suction valve 48. Another port 49 connects the intermediate and upper passageways 45 and 46 and the port is provided with a pressure valve 50. On the suction stroke of the surge pump the valve 48 opens and the hot condensate from the pipe 25 is drawn through the lower passageway 44 into the intermediate passageway 45. On the pressure stroke of the surge pump, the valve 48 closes, valve 50 opens, and the condensate is forced from the intermediate to the upper passageway and on through pipes 30, 31 and backtrap line 32 to the heating coil 12.

The invention has been described specifi- 'cally herein with special reference to that phase of the invention involving the cyclic return to a heating or cracking zone of reflux condensate obtained in the decomposition of hydrocarbon oils and although the preferred embodiment of the invention has been set forth in connection with apparatus having a particular construction and arrangement of parts and mode of operation, it is obvious that various changes and modifications may be made therein, while securing to a greater or less extent some or all of the benefits of the invention, without departing from the spirit and scope thereof. Therefore, only such limitations should be imposed as are indicated inthe appended claims.

What I claim is:

1. Apparatus for treating hydrocarbon oils comprising a charging line, a pump for forcing oil through the charging line, means for heating the oil in transit, a still wherein distillation of the heated oil is effected, a fractionating tower for separating the vapors evolved in the still, a surge pump having a surge line for pumping the hot condensate from the fractionating tower back to the heating means, and meansfor positively introducing a cooling medium into the surge line of the surge pump to maintain the liquid therein cooler than the oil being pumped.

2. Apparatus for treating hydrocarbon charging line, a still wherein the heated oil is treated, means for withdrawing products of the treatment from the still, means for separating the lighter constituents of the products withdrawn as a final product, a surge pump having a surge line for returning heavier constituents while still hot to the heating means, and means for introducing fresh charging stock from the charging line into the surge line to lower the temperature of the oil therein.

' In Witness whereof I have hereunto set my hand and seal this 6th day of August, 1925.

OTTO BEHIMER.

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