US3672958A

US3672958A - Industrial dry cleaning cooker-still

Info

Publication number: US3672958A
Application number: US9698A
Authority: US
Inventors: Albanis P Mccandlish
Original assignee: McGraw Edison Co
Current assignee: McGraw Edison Co
Priority date: 1970-02-09
Filing date: 1970-02-09
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27

Abstract

An industrial dry cleaning cooker-still for salvaging solvent such as perchlorethylene from oil residues comprises a cylindrical tub mounted horizontally and provided with heating ducts on the outside wall of the lower half portion thereof and with a surrounding jacket to form an air chamber open at the bottom and top for causing the upper half portion of the tub to be heated by convection. A rotor in the tub has a series of blades successively spaced along and around the rotor shaft which are set oblique to provide a screw propeller effect on the contents. The blades have outer arcuate edges adjacent to the wall of the tub and have leading and trailing cutter fins. The rotor is driven back and forth in opposite directions so that it will churn and cut up the contents while shifting the same back and forth along the tub. A scouring powder is added to the oil residue to keep the walls of the tub clean of encrustation. Upon driving the rotor in one direction only the contents are propelled out an unloading door.

Description

INDUSTRIAL DRY CLEANING COOKER-STILL 4 Sheets-Sheet 1 Filed Feb.

INVENTOR ALBANIS P. MCCANDLISH AGENT June 27 1972 l A. P. MCCANDLISH 3,612,958

INDUSTRIAL DRY CLEANING COOKER-STILL Filed Feb. 9, 1970 4 Sheets-Sheet 2 CONDE/USER Bax INVENTOR ALBANIS P. MCCANDLISH AGENT AME /A/LET as STE/7M DUC 7" 4 Sheets-Sheet 5 A. P. MGCANDLISH INDUSTRIAL DRY CLEANING cooKER-STILL June 27, 1972 Filed Feb.

Al M E E a, Wp 3 l A/ el. VP L n 6 d H||IE M \m= mf uw 4 e 6 5 T01 4 m 2 2 IAT 4 7 w.: E@ 2 4 L 8T@ 2 m f D Ilm ww .E S nn uw Mm m mw ff 2; F9 r 4 5 s 2 2 |H|Iu n A G m W 12E: 5 m m E. Mm g A 6 L ww, we 3 2 Ma J am 2 O L mdf .Il "Il m l l l n l l l I l f- INVENTOR ALBAN|5 P- MCCANDLSH BY /LvL 7V- AGE T June 27, A. P- INDUSTRIAL DRY CLEANING COOKERSTILL 4 Sheets-Sheet 4 Filed Feb. 9, 1970 INVENTOR ALBANIs P. MCCANDUSH AGENT United States Patent O 3,672,958 INDUSTRIAL DRY CLEANING COOKER-STILL Albanis P. McCandlish, Cincinnati, Ohio, assigner to McGraw-Edison, Elgin, Ill. Filed Feb. 9, 1970, Ser. No. 9,698 Int. Cl. B01d 3/02, 3/ 00, 1 /00, 1/30; B011? 11/60;

Dof 29/00 U.s. cl. 2oz- 17o 2 Claims ABSTRACT OF THE DISCLOSURE An industrial dry cleaning cooker-still for salvaging solvent such as perchlorethylene from oil residues comprises a cylindrical tub mounted horizontally and provided with heating ducts on the outside wall of the lower half portion thereof and with a surrounding jacket to form an air chamber open at the bottom and top for causing the upper half portion of the tub to be heated by convection. A rotor in the tub has a series of blades successively spaced along and around the rotor shaft which are set oblique to provide a screw propeller effect on the contents. The blades have outer arcuate edges adjacent to the wall of the tub and have leading and trailing cutter fins. The rotor is driven back and forth in opposite directions so that it will churn and cut up the contents while shifting the same back and forth along the tub. A scouring powder is added to the oil residue to keep the walls of the tub clean of encrustation. Upon driving the rotor in one direction only the contents are propelled out an unloading door.

An object of the invention is to provide a novel form of such cooker-still which has improved operating eiciency and an improved action which maintains the tub walls clean of encrustation to avoid the need for any difficult manual cleaning operations.

Another object is to provide such cooker-still which when the motor is driven in one direction only will propel the contents out through an unloading door at one end of the still.

These and other objects and features of the invention will be apparent from the following description and the appended claims.

In the description of my invention reference is had to the accompanying drawings of which:

FIG. l is a perspective view of the present cooker-still;

FIG. 2 is a rear View with parts broken away;

FIG. 3 is a vertical section taken on the line 3-3 of FIG. 2;

FIG. 4 is a fractional side View showing the heating ducts; and

FIG. 5 is a perspective view partly broken away of the rotor blade arrangement.

The present cooker-still comprises a cylindrical tub (FIGS. 2 and 3) welded at the ends to rectangular walls 11 and 12 (FIG. 3). The top corner portions of the front and back end walls are joined at the sides of the tub by inverted U-shaped angle iron structures 13 (FIG. l). These angle iron structures are joined at the ends of the tub by lateral angle irons 14 (FIGS. 2 and 3). The lower corner portions of the front and back end walls are joined at the sides of the tub by upstanding U-shaped angle iron structures 15. The latter structures 15 extend below the end plates to form a pair of legs by which the cooker-still is set on a Hoor or other support. At the axis of the tub there are end bearings 16 and 17 (FIG. 3) in which a rotor shaft 18 is journaled. The shaft has an outward eX- tension at one end provided with a drive sprocket 19 coupled by a chain 20 to a drive sprocket-21 (FIG. 2) of a motor 22. The motor is supplied with power as from a "ice 110 volt A.C. line via a switch box and reversing timer 22a (FIG. l) typically of the small motor-operated cam type. Typically, the motor will drive the rotor shaft at about 3 r.p.m. and the timer will reverse the motor about twice per minute. The reversing timer may however be cut out at will as by pressing a push button 22b so that then the motor will drive the rotor in one direction only for unloading the tub as is later described.

The rotor shaft 18 (FIGS. 2 and 3), which is square in cross section except for its journaled end portions, has a series of U brackets 23 riveted thereto at equal intervals therealong with each being advanced by from the preceding one. Secured to these U brackets are radial arms 24 the outer ends of which have oblique slots receiving respective blades 25. Each blade has an arcuate cutter edge 26 uniformly spaced from the inside wall of the tub. These blades are provided with cutter fins 27 and 28 (FIGS. 3 and 5) at the leading and trailing edges with the cutter fins being positioned at right angles to the shaft 18. The blades are all set oblique in the same direction so that when the shaft is turned in one direction only they will have a screw propeller effect on the contents to move the same along the tub while at the same time the arms 24 have a churning effect and the

fins

27 and 28 have a cutting effect to avoid conglomerating the contents into any one large mass which might stall the drive motor. However, during the operation of the cooker-still the drive motor is reversed at regular intervals, as above-mentioned, the effect of which is to shift the contents back and forth along the tub while churning and cutting up the same.

In the front end wall 11 there is an unloading door 29 (FIG. l') opening to the lower half portion of the tub. This door is held closed by two diametrical extensions 30 having slots 31 extending up from the bottom and receiving screw clamps 32 to hold the door tightly closed against a sealing ring, not shown. When the screw clamps are unthreaded slightly the door can be lifted from its mounted position. When the door is opened and the drive motor is turned in an unloading direction only the contents are propelled along the tub and out of the opening by the propeller action of the blades.

The contents comprise principally a heavy oil resid-ue laden with perchlorethylene which must be heated as it is churned to drive off the perchlorethylene to be salvaged. 'Ihe oil residue is fed into one end of the tub via a pipe P, (FIGS. l and 3) and a lter powder or filter sludge containing such powder is fed into the other end of the tub via a pipe P2 (FIGS. 2 and 3). The filter powder serves to scour the inside wall of the tub` as the contents are churned back and forth by the rotor blades 25.

The tub is heated by steam ducts 33 (FIGS. 3 and 4) applied back and forth in side-by-side arrangement length- Wise of the tub over the outside wall of the lower half portion thereof. The ducts are in two groups each applied over about one-fourth the circumference of the tub. Steam from a suitable source is fed Via ducts 34 and 35 (FIGS. 1 and 2) to the upper ends of the respective groups of heating ducts. The lower ends of the two groups off ducts are joined at the bottom by a pipe 36 and provided with a common outlet 37 for the condensate.

Surrounding the tub and steam ducts in spaced relation thereto is a jacket 38 (IFIGS. l and 2) sealed at the ends to the two

end walls

11 and 12. This jacket has an air inlet opening 39 longitudinally of the tub at the bottom thereof and an air outlet opening 40 longitudinally of the tub at the top thereof. The air is thus drawn in from the bottom and expelled at the top by the heating action of the steam ducts, and may be even moved by forced circulation if desired, to cause the upper part of the tub to be heated from the steam ducts by convection.

As the oil residue contents are heated and churned back and forth the perchlorethylene vapors are driven off and fed by insulated pipes 41 and 42 (FIGS. 1, 2 and 3) through the

end walls

11 and 12 to a condenser box 43 mounted on standards 44 at the top of the tub. These condensers are provided with finned coils 45 (FIG. 3) through which cooling water is passed via inlet pipes 46 and outlet pipes 47. The vapors enter the condenser typically at 250 F. and are condensed by the cooling coils and drained as a liquid at the bottom into a water separator 48 (FIG. l1). After being freed of water content by the separator the essentially pure perchlorethylene is drained off by a pipe 49 into a suitable storage tank not shown. Since in industrial dry cleaning there is a high proportion of oil in the dirty solvent, there is a heavy concentration of oil with the filter powder after the mixture is cooled dow-n. The oil and powder settle to the bottom. The free oil is drawn olf through a spigot S ('FIG. 1) before the door 29 is opened to unload the oil saturated powder.

From the foregoing description it will be apparent that novel features of the invention reside in a cylindrical tub horizontally mounted so that it is adapted for automatic cleaning and unloading, in a unique agitator which is reversed periodically to mix, churn and shift the contents back and forth while cutting up the contents into small masses for efficient removal of the perchlorethylene, in heating the lower half of the tub by steam ducts while providing a surrounding jacket for air ow effective to heat the upper part of the tub by convection, in churning and agitating the contents by oblique scraper blades which continually scour the inside wall of the tub to keep the walls clean of encrustations and in driving the rotor blades in one direction only during unloading to move the contents out of one end of the tub by a screw propeller action. These features have not only proven to give a very efficient distilling action but by tests and field operation they are found to eliminate the necessity for hand scraping and chiseling of baked-on residue as has been required with commercial dry cleaning cookerstills of the prior art.

The embodiment of my invention herein particularly shown and `described is intended to be illustrative and not necessarily `limitative of my invention, since the same is subject to changes and modifications without departure from the scope of my invention, which I endeavor to express according to the following claims.

I claim:

1. An industrial cooker-still comprising a cylindrical tub for a content of solvent, oil residue and scouring powder, means mounting said tub in an axially horizontal position, a rotor shaft in said t-ub journaled at the axis thereof, narrow radial arms on said shaft having relatively wide blades mounted on the outer portions thereof, said blades having outer arcuate edges adjacent to the 4 inside wall of said tub, said blades being set oblique relative to the circumferential paths of travel thereof giving a screw propeller effect during rotation of the shaft while said radial arms have a churning effect on said contents, means for driving said rotor shaft alternately in opposite directions whereby to agitate and concurrently shift said contents back and forth with a scrubbing action along the wall of the tub, and said blades being pro- 'vided respectively at their leading and trailing side edges with leading and trailing cutter fins at right angles to said shaft for cutting the contents into small masses as the rotor shaft is turned in either direction.

2. An industrial cooker-still comprising a cylindrical tub for a content of solvent, oil residue and scouring powder, means mounting said tub in an axially horizontal position, a rotor shaft in said tub journaled at the axis thereof, narrow radial arms on said shaft having relatively wide blades mounted on the outer portions thereof, said blades having outer arcuate edges adjacent to the inside wall of said tub, said blades being set oblique relative to the circumferential paths of travel thereof giving a screw propeller effect during rotation of the shaft while said radial arms have a churning effect'on said contents, means for driving said rotor shaft alternately in opposite directions whereby to agitate and concurrently shift said contents back and forth -with a scrubbing action along the wall of said tub, and cutter fins on said blades in line with the direction of travel of the blades to slice up the oil residue with said scouring powder and prevent the same from conglomerating into large masses which might stall the drive of the rotor.

References Cited UNITED STATES PATENTS 3,169,537 2/ 1965 Fuhring 134-111 2,318,455 5/ 1943 Black 202-170 1,935,183 11/1933 Hapgood 202-181 X 2,123,439 7/1938 Savage 202-170 D 2,140,623 12/ 1938 Hetzer 68-18 2,427,718 9/1-947 Denys 203--89 X 2,779,723 1/1957 Prymek 202-170 2,801,958 8/1957 Fortenbacher et al. 202-170 2,832,726 4/1958 Norment 202-181 1,775,017 9/11930 Carleton 219'38 2,484,070 10/ 1949 Boyce 259--45 2,563,937 8/1951 'Keight et al. 259-9 3,273,863' 9/ 1966 Lodige et al 259-9 3,368,723 2/ 1968 Hardeman 259-39 NORMAN YUDKOFF, Primary Examiner I. SOFER, Assistant Examiner U.S. Cl. XB.