US1864722A

US1864722A - Synchronous gap potential control for treaters

Info

Publication number: US1864722A
Application number: US217680A
Authority: US
Inventors: Harmon F Fisher
Original assignee: Petroleum Rectifying Co California
Current assignee: Petroleum Rectifying Company of California
Priority date: 1927-09-06
Filing date: 1927-09-06
Publication date: 1932-06-28
Anticipated expiration: 1949-06-28

Description

June 28, 1932. F, lsHER I 1,864,722

SYNCHRONOUS GAP POTENTIAL CONTROL FOR TREATERS Original Filed SeptvG. 1927 HTTORjx/EK I I E x/TOR:

Patented June 28 31932 entree stares ATWE terrace HARMON F. FISHER, 0F LUNG- BEACH, CALIFQRNIA, ASSIGNOR T0 PETRQLEUBEE RECTI- FYING CQEZZEANY OF CALIFORNIA, 0F IDS ANGELES, CALIFORNIA, A CQBPORATION 0F CALIFORNKA SYNCHNOUS GAP PUTENTIAL CONTRQL F03 TREAS Application filed September 6, 1927, Serial NeQMZGBO. Renewed @otober 13, 1981..

This invention relates to electrical treating apparatus commonly used for die-emulsifying petroleum emulsions. A common form of apparatus used for this purpose consists of a tight container in which a grounded elec.

trode and a live electrode insulated from the container are-supported. An electric field is established in the space between the electrodes by suitable means and the emulsion consisting of petroleum and particles of water is passed through this treating space wherein the water particles are coalesced into masses of suficient size to gravitate from the oil. The water and other residue are removed through an outlet pipe at the bottom of the container and the dry oil is taken from the container near the upper end thereof.

This invention relates particularly to an electrical dehydrator especially adapted for use in treating very we emulsions; that is, emulsions having large water content. The common form of electrical dehydrator, as described above, is not suitable for treating very wet emulsions but it has been demonstrated that such emulsions may be successfully treated if the apparatus is designed to im ress a high potential on the treater periodlcally for short durations of time. The theory of this action is that the sudden increase of potential to a very high degree will set up a local potential diiference in the field between the electrodes which is sufficient to treat a small quantity of the emulsion. This action is carried on until the emulsion becomes dry enough to establish a large difference of potential entirely across the treating gap.

It is an object of this invention to provide an electrical treating apparatus in which an extremely high potential is periodically impressed on the treater.

It has been my experience that diflerent types of emulsions treat best at difierent potentials; in other words, some emulsions would be treated much more eficiently if they were subjected to a constant field intensity of a certain magnitude and other emulsions would be treated best if they were subjected to a constant field intensity of a difi'erent magnitude.

It is accordingly one of the objects of this ing current source,

invention to provide a treating apparatus of the character mentioned in which the mag nitude of the potential impressed on' the treat er may be controlled.

My invention comprehends the use of a high tension reactance in the circuit of the treater. This high tension reactance may be shunted out by means of a shunt which extends around it in the circuit. Automatic means is provided for closing the shunt circuit so that the full potential produced by the transformer is impressed on the treater.

It is a salient advantage of this invention to provide a treating apparatus in which the full potential may be impressed on the treater at any point of the alternating current cycle.

Other objects of the invention and the advantages thereof will be pointed out in the ensuing description.

My invention may be best understood by reference to the accompanying drawing, in which Fig. 1 is a diagrammatic view illustrating a preferred form of the invention.

Fig. 2 is a diagram showing a wave form of the potential impressed on the treater.

Referring to the drawing in detail and particularly to Fig. 1, the treater of the invention is designated by the numeral 11. This treater 11 has a tight shell 12 in which a grounded electrode 13 is supported by suitable straps 14. Hung on a cable 15 above the grounded electrode 13 is a live electrode 16. The cable 15 extends through an insulation bushing 17 whereby it is insulated from the shell 12. Emulsion to be treated is introduced into the lower part of the treater 11 below the grounded electrode 13 by means of an emulsion inlet pipe 19. Treated oil is withdrawn from the upper end of the treater 11 by means of an oil outlet pipe 20, and water and other residue is withdrawn from the lower part of the treater 11 by means of a drain pipe 22.

My invention utilizes an electricity supply means which is preferably in the form of a step-up transformer 25 having a primary winding 26 connected to a suitable alternatand a secondary winding 27. One side of the secondary winding i 27 is connected to the shell 12 by means of a conductor 28 and is consequently connected to the grounded electrode 13. This side of the secondary circuit is grounded as illustrated in the drawin The other side of the secondary winding 2 is connected by means of a conductor 30 to a otential reducing means, preferably in the orrn of a high tension reactance 31. The high tension reactance 31 is connected by a conductor 33 to the outer end of the cable 15 which is electrically connected to the live electrode 16. Connected around the high tension reactance 31 is a shunt circuit 34 which has a gap 35. In parallel with the ap 35 there may also .be a condenser 36. e gap 35 of the shunt circuit 34 is adapted to be closed" by a closing bar 37. This closing bar 37 is adapted to be rotatably operated by a suitablie motor 38, as illustrated diagramma ically in Fig. 1. When the closing bar 3 moves so that the ends are adjacent to the points of the gap 35, the high tension reactance 31 is shunted around. Shunted across the conductors 28 and 30 between the secondary winding 27a nd the high tension reactance 31 is an electrlclty storage means in the form of a maln ,condenser 40.

The operation of my invention is explained as follows:

The transformer 25 is excited so that a secondary current is set up in the circuit including the grounded and

live electrodes

13 and 16. The potential at the electrodes is considerably less than the potential at the secondary winding of the transformer because of the action of the high tension reactance 31 which chokes back the voltage. The emulsion to be treated is introduced into the tank 12 byv the emulsion inlet pipe 19, and it passes between the

electrodes

13 and 16 where an electric field is set up. The emulsion which this treater is adapted to treat is very wet and has a large water content, the water particles thereof tending to chain up so as to shortcircuit the electrodes. This chaining up action reduces the potential between the electrodes by permitting a h eaVy flow of current.

In the ordinary treater a heavy flow of current is drawn until the ,short-circuiting of chains of masses of water are broken in some manner.

In my invention the treating action is as follows: v

The condenser 40 which is connected across the wires 28 and 30 is stored withelectricity. The potential difference between the wires 30 and 33 adjacent to the high tension reactance 31 is considerable by reason of the reactance 31, and the difference in potential between the points of the ap 35 is also considerable. When the particles of water in the emulsion chain up between the electrodes and tend to draw-a heavy current, the diiference in potential of the opposite sides of the high tension reactance 31 and of the points of the spark gap 35 is considerably increased and the result is that there is a tendency for a spark to jump across the gap 35 and shunt out the high tension'reactance 31. The gap 35, however, is too large and there will be no sparking. The motor 38 being in operation rotates the closing bar 37. When the' closing bar 37 moves into closin position, in which position the ends are ad acent to the points of the gap 35, the shunt circuit 34 will be closed and the hi h tension reactance 31 will be shunted out. This provides a path around the high tension reactance and the electricity which is stored up in the main condenser 40 may flow to the treater, establishing a great potential difierence between the two

electrodes

13 and 16. This sudden rise in potential diiierence is suficient to cause a high localized potential gradient in the treating gap between the electrodes and scient to treat a small amount of emulsion. T have found that better results are obtained when the condenser 36 is used than when it is not, this condenser tending to produce a more sudden rise of potential. This condenser 36, however, is not indispensable.

Referringto Fig. 2, the numeral 41 represents a wave form of the potential which is impressed on the treater 11. The ordinary Wave form is indicated by dotted lines 42 and is the potential ordinarily impressed on the treater with the high tension reactance included in the circuit. on the shunt circuit 34 is closed and the high tension reactance 31 is sorted from the circuit, a high potential peak 43 occurs having an extremely steep wave front, which of course denotes an instantaneous increase in potential. The duration of the peak 43 is ordinarily very short and is usually very high so that the efiect on the emulsion is such as to treat a small amount thereof. This instantaneous rise in potential is absolutely necessary in order to establish a localized difference in potential of a potential gradient suficient to have a de-emulsifying eflect on the emulsion.

The duration of the wave peaks 43 is readily increased or shortened by the sizes of the end faces of the closing bar 37. I prefer to operate the closing bar 37 synchronously with the secondary "current, but it should be un- .Fig. 2. This is accomplished by causing the closing bar 37 to blose the shunt circuit 34 at a different point on the sine wave .42.

This invention is an improvement over the inventions described in my copending applications, one entitled Method of dehydrating emulsion, filed August 30,1926; Serial No. 132,375, and the other entitled Dehydrated apparatus using high tension reactance, filed Se tember 9, 1926, Serial No. 134,476.

claim as my invention: 1. In an apparatus for dehydrating emul-. sion, the combination of: a pair of electrodes;

.an electricity'supply means for supplying electricity to said electrodes ;'potential reducing means for reducing the potential im-,

pressed on said electrodes; and mechanically operated shunting means ,for'shunting out said potential reducing means.

2. In an apparatus for dehydrating emul-. sion, the combination of: a. pair of electrodes; an electrlcity supply means for. supplymg electricity to said electrodes; a reactance for reducing the potential impressed on aid electrodes; and mechanically operated shunting means for shunting out said reactance.

3. In an apparatus for dehydrating emul-.

sion, the combination of: a pair of electrodes; an electricity suppl means for supplying electricity to said e ectrodes; poten-'. tial reducing means for reducing the potential impressed on said electrodes; mechanically operated shunting means for shunting out said potential reducing" means; and an electricity supplI'y means.

,- sion, the combination of: a pain of electrodes; an electricity supply means for supplying electricity to said electrodes; :1. reactance for reducing the tential impressed on .said electrodes; mec anically operated shunting means for shunting out said reactance; and an electricity storage means connected to said sup 1y means.

5. In an apparatus or dehydrating emulsion, the combination of: a pair of electrodes; an electricity supply means for supplying electricity tosaid tialreducing means for reducing the potential impressed on said electrodes; a shunt circuit around said potential reducing means,

ing said gap for periodically closing said said shunt having a gap; and means for closshunt.

sion, the com ination of; a pair of electrodes; an electricity sup ly means for supplying electricity tp sa1 electrodes; a reactance for reducing the potential impressed on said electrodes; a shunt circuit around said gap for periodicaliy storage means connected tosaid' an apparatus for dehydrating emulctrodes; potenmeans for closing closing said shunt circuit; and an electricity storage means connected to said sup ly-means.

8. In an apparatus or dehydrating emulsaid shunt having a ga sion,. the combination of: a pair of electrodes; an electricity suppl means for supplying electricity to said e ectrodes; potentialjreducing means for reducing the potential impressed on said electrodes; and shunting means for said potential reducing means and driven in synchronism with the electricity supplied to said electrodes. A

9. In combination: a pair of electrodes; supply. means for supplying electricity to said electrodes; a potential reducing means for reducing the potential supplied to said v electrodes to a fraction of the potential of said supply means; means operating in synchronism with said potential of said su ply means for successively shunting sa d potential reducing means; and means cooperating with said potential reducin means to form an oscillating potential w en the synchronously driven means shunts said po-' tential reducing means. v

10..'In an apparatus for treating an emuls sion, the combination of: -a pair of lectrodes between whichis positioned the emulsion to be treated; a supply means for iiflpressin a potential diflerence between said electro es; circuit means'for connecting said supply means to said electrodes; a potential re ucmg means connected ,to said circuit.

1 means and through which moves the current i reaching said electrodes whereby the voltage drop across said potential reducingmeans; decreases the potential applied to said electrodes; and a synchronous gap connected around said drlven 1n syn 'plotential reducing means and ronism with the current, su .l

plied to said electrodes ion-periodical shunting. said potential reducingmeans.

In testimony whereof I have hereunto set 111 hand at Los Angeles, California, this" 26th ay of August, 1927.

Ill

HARMON- FISHER.

6. In an a aratus for dehydratin emul- Pg 7 g