US1823470A - Separator - Google Patents

Description

Sept. 15, 1931, V, A ROHLlN 1,823,470

SEPARATOR Filed March 26, 1927 l [lll/,111.1111

Patented Sept. k15, 1931 `VICTOR A. ROBLIN, OF PHILADELPHIA, PENNSYLVANIA.

surnnnrron i Application mea March 26, 1927.y Serin No. 178,685.

HMy invention relates to the separation of suspended matter from a gaseous or vapor stream and more particularly to the separation ota suspended liquid, as water, from a g8 vapor, as,y for example, steam. y

rkMy invention resides in the method of, and apparatus for, causing a gaseous or vapor streamA to'assume the form of a ribbon orsheet traveling ata relatively high velocvl0 ity, ychanging-the direction of said sheet to elfect the separation of suspended matter, more'particularly, a liquid, as water, and thereafter providing separate paths for said 'separated vmatter and said stream. v l YMy i-nvention further resides in a method and apparatus of the character above described in which thepressure or" the vapor afternthe removal of a suspendedy liquid, is increased so that the initial and final pressures of said vapor are substantially equal.

Further, my invention resides in `the method of, and apparatus for,progressively increasing the velocity of a gaseous or vapor stream, more particularly in a vdownward direction, in a path having an increasing rate` et change `of direction in onedirection toeffect theseparation of suspended matter, morerspecically, a liquid, as water, from the stream, providing separate paths for the separated matter and thestream, and thereafter permitting the streamy t0 progressively decrease in velocity, more particularly'in an upward direction. e t

yStill further, my 'invention resides in a method and apparatus of the character above described in vwhich a pressure, substantially equal to theinitial pressure of the stream, is created in the outlet passage for the separatedmatter, and more particularly, in `which such a'pressure is created by the locationyof the outlet passage with respect tothe stream. f

Myinvention further resides in the method and apparatus hereinafter described and claimed. t f' Y For an illustration of a form my invention may take, referencey is made to the accompanying drawings, in which: 50 Fig. 1 is an elevational view, in section, of

my linvention as applied to the outlet of a boiler taken on line 1 1 of Fig. 2. Fig. 2 is an end elevational view, partly in section, of the structure disclosed in Fig. ltaken on line 2--2 of Fig. 1.

Referring to Fig. 1, the boiler drum 1 is provided with a steam outlet pipe 2 which terminates within the boiler, in an inverted T having each end of its cross-arm open and connected to a separator 3. For convenience but one separator is shown, which in some installations may be sufficient, although it is to be understood that in the illustration herein disclosed and describedtwo separators which are substantial duplicates are utilized. The curved casing members 4 preferably metal castings, as of iron, are provided at each end with a flange 5 which in each in-` stance determines the position ofy one of the' partition members 6 extending the length of the casing defined by the members 4 and the end capsor plates 7 and 7 a, preferably also ot cast iron, fastened, such as 'by machine screws 2O lto them. The' major part of the inner face of the'cas'ing 4 is a portion of a curve having a progressively changing radius of curvature, such as, for example,-a parabola. The surface ot' the partition mem-4 ber @adjacent the casing is curved and cooperates withV the curved inner face of the casing to form a passage 11 of gradually decreasing Vcrosssectional area from' top to bottom. The plate 7a may be dispensed with if the flange of the steam outlet pipe 2 is designed to serve as an end wall of the sep# arator.

An inclined plate Shaving its lower end substantially in alignment with the bottom of a wide slot 15 in the end plate 7 and its higher end substantially in registration with the -upper side of the steam outlety opening,y extends lengthwise of the casing dividing it into an'upper or inlet chamberl and a lower or outlet chamber 17. Extending centrally of the plate 8 is a raised portion corresponding inshape to .a segment of a hollow cone, dividing it into two troughs-18 which increase in width as they approach the drainopening or slot 15. The outlet chamber 17 is of increasing cross-sectional area as the steam outlet is approached.

As shown more clearly in Fig. 2, the lianges having notches21 also locate and Support a dividing rib member which extends lengthwise of the bottom of the casing and cooperates with the partition members 6 and'with the casing members 4L to form two pairs of diverging passages. Thefpassages 12 comprising one pair increase in cross-sectional area as they approachthei-rterminationin-the outlet chamber 17. The passages 13 comprising the other pair may either discharge directly to the inside of the boiler,.to. the inside of the boiler through the drip chamber 14 provided with tapped holes 14a, or toay point outside the boiler through pipes, not shown,

threaded, into theholesallla. .-The drip chamber Vwhen ,usedVK is fastened to the lower sur- Jface of the separator casingpby any suitable means such-as machine screws 19. The passagesv 11 and 12, substantially rectangular in cross-seetion,`form"a U-shaped Venturi-tube rical with respect jto the center line. of Fig. 2 for convenience, the description of.

operationofv the device will be directed to that portion shown in section in Fig. 2. As the steam-enters at. the top and at` the open vend ot the separator, much of the Jreewater drops Vupon the inclined plate 8 and is returned to the boiler by the trough 18. The steam and the remain-ing water travelingv at a relatively low velocity enter the. mouth 22' of the passage 11. :The larger Orl-heavier particles of water lstrike the.` curved wall in the region denoted generally byX and ow downfitv torthe drip port 13. `Due tothe shape of the passage 11, the velocity of the stream increases progressively and in a path having aprogressively increasing curvature. As the momentum of the lighter and still lighter water particles increases, vdue tothe increase of the stream velocity, and a's'the curvature of the path increases, the particles in turn, according to their mass, separate from the streamV proper and flow down the curved wall' to the dripport. By this'fcon- 'secutive separat-ion of particles according to -their mass',an'dby havingthe'particles strikingl the wall tangentially, there is no spatter- 'ingdueto vany ldirect impact of free water travelingat high velocity, which would ordinarily result in the returning of a quantity of separated water to the stream which would then carry it to the outlet as Vfree water. Moreover the separation of each particle isv accomplished at the lowest velocity that will accomplish separation of particles of its size, which` further reduces the tendency to spatter.

-The lightest remaining particles' areV carried across the thin sheet of steam as the passage reverses its direction at or immediately beyond the throat 11a, By positioning the separator as shown s0 that the velocity is increased in a downward direction and decreased in an upward direction, it is evident that the particles are first given an acceleration in a downward. direction by the combined yeitect of the stream velocity or iow and the relatively small effect of gravity.y As the stream reverses its direction, the water particles to be carried to the outlet would have to be given a vertical acceleration in an opposite, that is, an upward. direction, bythe.' stream. During the reversal, there is a period inwhich the particles have no vertical velocity due to the stream, and are traveling inv a horizontal path. Gravity, which continues to impart a vertical acceleration to the particles, increases the extent of their downward travel, increases the period of substantially zero vertical velocity due to the streamv flow, and yretards their acceleration in an upward direction. The net result is that the accelerationrot gravity contributesV to the separationand makes it possible to realize a higher degree of separation than if the tangential action of the stream' alone was utilized. v

The passage or drip port 18 which conducts, the'separated water is so located that the waterleaves the steam path immediately after it. has attained" its highest velocity whichjmay be from 5,00() to '10,000 Jfeet per minute at rated load.` vIt is also'so positioned with respect to the vcurved-steam path that it is, in eifecta Pitot tube onvthe high pressure side of alcurved path offlow, and consequently the pressure therein closely approximates the original .pressure of the steam.

To explain more fully; assuming that the flow is in' a straight line,and neglecting friction, the pressure. in a Pitot tube is constant regardless of whether-it is located in the center of the stream or at a point intermediate the center and the side, and is equal to the s um of the static pressure andvelocity head of 'the stream. Further, if there has been a gradual increase ofv velocity from the source,'the pressure in the Pitot tube is Asubstantially .equal A to the pressurev of the source. K

lf, however, the flowis in a curved path, the pressure will vary across the width 0f thestream, being lowest at the side nearest the center of curvature and highest at the opposite side. The centrifugal force cre- 'atedH by the changey of" direction cause's a greater stream density at the latter which is indicated by a higher reading in the Pitot tube. It is therefore possible by so placing the tube in a curved stream, to compensate or over-compensatethe effect of frictional resistance, so. that the pressure produced is practically the same as that ofthe original source. As the ypoint of high velocity in a Venturi tube islikewise the point of low pressure, it would ordinarilybe impracticabley to effect a transfer from this point to one ofhigherr pressure. I-Iowever, in my invention by reversing the direction of flow at the wthroat and in positioning the water discharge passage so that there is a pressure created as above dscribed, it is usually possible toydischarge the separated water directly into the boiler. In vany event, the difference in pi'esthe wedge-shaped rib member 1'0 and the up-y wardly turned extension of partition 6, so that the pressure in the outlet chamber is but slightly less than the initial pressure at the inlet. `The dry steam then passes from outlet chamber 17 through pipe 2 to the point of its application to useful work.

While the operation of my separator has been described asapplie'd to the sepa-ration of water from steam, its use is not rso restricted andthe methodk and structure may be applied in other instances in which it is desired to effect thek separationL of a solid or a liquid in suspension, from a Huid, either a vapor or a-gas.y When used forthe purpose herein described, the separator is preferably located within theboiler drum, although it is to be understood that it may be elsewhere in the outlet system.

What I claim is: l. Apparatus for separating moisture from a vapor comprising yarcuate members forming fluid passages, each passage having a progressively converging inlet, said arcuate members converging to a narrow slit longitudinally of the axis of said apparatus, and a separating member disposed opposite the discharge ends of said fluid passages and forming with said ,arcuate members diverging outlets for said vapor and escape outlets for the separated moisture. u

2. Apparatus for separating moisture from a vapor comprising sheetlilie arcuate members forming fluid passages, said passages first diverging and then converging towardsy each other, each passage having a progressively converging inlet, ysaid arcuate members converging to a narrow slit longitudinally of the axis of said apparatus, and a separating member disposed opposite the discharge ends of said fluid passages and forming with saidarcuate members diverging outlets for said vapor and escape outlets for the separated moisture.

3. Apparatus for separating moisture from avapor comprising arcuate members forming iiuid passages, each passage having a progressively converging inlet, a member disposed beneath said inlets and between said passages forming a chamber with the oppositely disposed arcuate members, said arcuate members converging to a narrow slit longitudinally of the axis of said apparatus, and a separating member disposed opposite the discharge ends of said fluid passages and forming with said arcuate members diverging outlets into said chamber and escape outlets for the separatednioisture.

4. In apparatus for drying a vapor, arcuate members forming .a pair of progressively converging passages, each of said passages i converging to a narrow slit longitudinal with respect to the axis of said apparatus and having its concave side facing the other, and means for abruptly changing the direction of iow of said vapor after passing through said slits, said means forming passages with the arcuate members for moisture and dry vapor respectively, the vapor passage having diverging walls.

Y 5. In apparatus for drying a vapor, arcuate walls forming a pair of converging passages, a member extending between said walls and forming therewith the upper wall of a chamber for leading off the dry vapor, said wall being inclined and .adapted to drain off excess moisture separated from the vapor before entering said passages. and separating structure forming the lower part of said chamber for separating moisture from the vapor and forming dry vapor passages leading into said chamber.

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