US3808631A

US3808631A - Device for removing a sludge from a surface

Info

Publication number: US3808631A
Application number: US00230948A
Authority: US
Inventors: K Shibata; Y Seika; S Kondo; I Sakamoto; K Yamada
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 1969-11-13
Filing date: 1972-03-01
Publication date: 1974-05-07
Anticipated expiration: 1991-05-07

Abstract

A device for removing a sludge from the surface of a liquid or from a floor such as a deck of a tanker includes a shovel which is adapted to be moved along the sludge with its opened mouth positioned to receive the sludge. The construction includes a connection for directing a high velocity liquid jet into the shovel in the vicinity of the mouth to impinge upon the sludge and to break it up into a slurry and, in addition, means are provided for withdrawing the slurry upwardly through a conduit for discharge at a remote location. The discharging connection advantageously includes a liquid ejector which is operated partly by the conduit connected for supplying the high velocity jet of liquid to the shovel and which is connected to the shovel for providing a withdrawing suction or pumping action on the slurry which is formed in the shovel. In a further embodiment, the interior of the shovel is provided with a screen or grate across the shovel interior onto which the slurry is directed and against which the high velocity liquid jet is directed. The action breaks up the slurry elements into finer elements for withdrawal through the discharge conduit. A still further embodiment includes an intermediate chamber at the rear of the shovel which is adapted to receive the slurry after it is first acted upon by the high velocity jet and which includes a plurality of turning water streams which are directed in a whirling flow to cause a rotation and further pulverizing of the slurry material before it is delivered through the discharge conduit.

Description

United States Patent [191 Shibata et al.

[ DEVICE FOR REMOVING A SLUDGE FROM A SURFACE [75] Inventors: Katsuhiko Shibata; Yajuro Seika,

both of Nishisono'gi-gun; Iwao Sakamoto, Nagasaki; Kango Yamada, Nagasaki; Setsuo Kondo, Nagasaki, all of Japan [73] Assignee: Mitsubishi Jukogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Mar. 1, 1972 [21] Appl. No.: 230,948

Related US. Application Data [63] Continuation of Ser. No. 876,371, Nov. 13, 1969,

i451 May 7, 1974 Primary Examiner Robert W. Jenkins Assistant ExaminerAlan 1. Cantor Attorney, Agent, or Firm-John J. McGlew [57 ABSTRACT A device for removing a sludge from the surface of a liquid or from a floor such as a deck of a tanker includes a shovel which is adapted to be moved along the sludge with its opened mouth positioned to receive the sludge. The construction includes a connection for directing a high velocity liquid jet into the shovel in the vicinity of the mouth to impinge upon the sludge and to break it up into a slurry and, in addition, means are provided for withdrawing the slurry upwardly through a conduit for discharge at a remote location. The discharging connection advantageously includes a liquid ejector which is operated partly by the conduit connected for supplying the high velocity jet of liquid to the shovel and which is connected to the shovel for providing a withdrawing suction or pumping action on the slurry which is formed in theshovel. In a further embodiment, the interior of the shovel is provided with a screen or grate across the shovel interior onto which the slurry is directed and against which the high velocity liquid jet is directed. The action breaks up the slurry elements into finer elements for withdrawal through the discharge conduit. A still further embodiment includes an intermediate chamber at the rear of the shovel which is adapted to receive the slurry after it is first acted upon by the high velocity jet and which includes a plurality of turning water streams which are directed in a whirling flow to cause a rotation and fur ther pulverizing of the slurry material before it is delivered through the discharge conduit.

3 Claims, 7 Drawing Figures Mummy 1 m 3.808531 SHEET 1. OF 2 INVENTORS KATSUHIKO SHIBATA YA'JURO SEIKE IWAO SAKAMOTO KANGO YAMADA SETSUO KONDO 7M4] MW ATTORNEYS DEVICE FOR REMOVING A SLUDGE FROM A SURFACE This is a continuation, of application Ser. No. 876,371 filed Nov. 13, 1969; now abandoned.

SUMMARY OF THE INVENTION This invention relates in general to the construction of devices for removing sludges and in particular, to a new and useful device for removing accumulated matter such as sludge, sand and other from petroleum and which accumulate at the bottom of a tank of an oil tanker.

When an oil tanker enters the dock during a period of overall for unloading prior to entering into a ship yard the lifting of any sludge which has accumulated on the bottom of the oil tanker is effected. l-leretofore the sludge is removed by very primitive methods and by many workers entering the cargo oil tank after it is cleared of gases. The material is removed by shovels,

buckets and winches driven by an air motor. In recent large and the bottom area of a tank and the depth of a tank have been increased and therefore many workers and working hours have come to be spent for the operation of removing sludges from tanks of such large vessels. In addition, because of the shortage of personnel, development of more efflcient methods of sludge removal is very desirable.

In accordance with the present invention there is employed a shovel or scope member having an opening at one end which may be oriented toward the sludge material to be removed and which includes means for directing a high pressure liquid jet against the surface of the sludge as it is being scoped up'by movement of the slurry into the sludge material. The jet causes the ellapse of the sludge material and forms it into aslurry. The shovel itself is associated at its other end with a discharge conduit which is put under negative pressure preferably by an ejector which is actuated partly by a branch of the high velocity jet stream of liquid. In one embodiment the shovel is advantageously provided with a screen across its interior in order to provide an impounding surface for the sludge against which the high velocity jet is directed to ensure that the sludge is broken up into small particles. In a further embodiment the shovel includes an after chamber into which the slurry is directed after first being acted upon by the high velocity jet. In the after chamber means are provided to direct liquid tangentially against the slurry and whirl it so as to ensure that it is pulverized into smaller particles before it is delivered through the discharge of the shovel.

Accordingly, it is an object of the invention to provide an improved device for removing slurries from the floor of a tank or the surface of a liquid and which includes a shovel or scope having an opened end which may be oriented toward the slurry and which includes means for directing a high velocity jet against the slurry which is picked up by the shovel, and wherein the shovel includes means for removing the picked up slurries through a discharge.

A further object of the invention is to provide a slurry removal shovel which includes a shovel head having an opening which is adapted to be positioned to scope up the sludge material and which also includes means for directing a high velocity jet against the sludge material to form it into a slurry and preferably to direct it against stream means for ensuring its being broken up into small pieces and which further includes means for turning the slurry in a water stream to provide a further comunuting of the materials, the construction including an ejector which is worked by a high velocity liquid to provide a negative pressure in the shovel for facilitating the discharge of the slurry.

A further object of the invention is to provide a sludge removal device which is simple in design, rugged in construction, and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its op erating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a top plan view of a sludge removal device constructed in accordance with the invention;

FIG. 2 is a partial front elevational view of the device indicated in FIG. 1;

FIG. 3 is a side elevational view of the device;

FIG. 4 is a section taken along the line IV-IV of FIG. 1; and

FIGS. 5, 6 and 7 are side elevational views of three separate alternate embodiments of the invention.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, in particular, the invention embodied therein in FIGS. 1 to 4, comprises a sludge removal devicegenerally designated 50 which is adapted to be moved along a surface or floor l to position sludge material into a front opening 52 of a shovel or scoop generally designated 7. The front opening 52 of the shovel 7 is provided with a forward flexible skirt l3 and side skirts I1 and 12. The skirt 13 is made shorter than the side skirts in order to accommodate the sludge material 2 which is to be picked up through the front end. The interior of the shovel 7 defines a mixing chamber 6.

In accordance with a feature of the invention, the shovel 7 is provided with a high pressure water conduit 3 which is connected to discharge liquid through an adjusting valve 5 at a connecting conduit 54 through one or more nozzles 4 which are oriented to direct the liquid downwardly against the slurry 2 which is delivered through the open end 52 and in a manner to cause it to be whirled and broken up in the mixing chamber 6. A branch conduit 56 extends from the high pressure water conduit 3 backwardly in a curve to discharge a portion of the high velocity water into a diffuser 8. The conduit 56 defines a narrow throat section or venturi 9 which is placed under negative pressure by the discharge of the liquid through the conduit 56 into the diffuser, so that the slurry which is formed in the mixing chamber 6 is directed upwardly through the diffuser 8. The shovel 7 is provided with a valve control and manipulating handle 10 and it includes a coupling 14 for connecting the high pressure conduit 3 to a water hose or flexible connection 15. The diffuser 8 is also provided with a coupling 16 for connecting this part of the device to a discharge hose connection I7.

The shovel 7 may be manipulated by one or two workers manually or by means an overhead lifting device to position it so that it moves along the entire surface of the deck I to lift up the sludge 2. The valve 5 is adjusted to provide the desirable removal action through the mixing chamber 6 and also to provide the desired jet force comminuting action on the sludge by liquid exiting through the nozzles 4. The action of the nozzles 4 causes a breaking down of the sludge 2 into smaller particles and the formation of a slurry. A further breaking down of the sludge layer is effected within the mixing chamber due to the whirling action in this chamber. The slurry is continuously removed through the venturi 9 and into the diffuser for the discharge through the discharge connection I7. The pressure of the water which acts upon the sludge and which provides the negative pressure for the discharge of the slurry may be regulated by the valve 5 and normally the pressure within the range of 7 to 8 killograms per square centimeter will be sufficient.

The shovel 7 of the invention permits removal of sludge by one or more workers who may rapidly move the shovel over the surface to be cleaned without re-- quiring the use of shovels or buckets and lifting winches which were required before the present invention.

In the embodiment illustrated in FIG. 5, there is provided a sludge removal device generally designated 60 which includes parts which are similar to the first embodiment and which are designated with the same number but with the addition of a prime. This construction differs from the embodiment indicated in FIG. I, principally in respect to the location of the diffuser 8 at a remote location from the shovel 7. The diffuser 8 is supplied with a high velocity jet of liquid through a valve 62 and a conduit 64 which is connected to the high velocity liquid conduit The liquid from the conduit 64 is discharged through conduit 9 to form an ejector action and a negative pressure on a flexible discharge connection I9' between the shovel 7 and the diffuser 8'. The diffuser 8 has a discharge which is connected to a flexible hose 17.

In the embodiment of FIG. 6, parts which are similar to the embodiments of FIGS. 1 and 5 are similarly designated but with double primes and the principle distinction of this construction over that indicated in FIG. 5 is that the shovel includes a filter or screen which is disposed across the width thereof at the interior to provide an impounding screen or grate onto which the slurry is directed and against which the high velocity liquid is directed from the nozzles 4". The mesh size of the screen 20 is advantageously such that the length of the diagonal is about 90 percent of the internal diameter of the slurry discharge pipe 19". The filter 20 prevents the movement of lumps through the device and provides an impounding surface on which the lumps may be broken down by the water jet issuing from the nozzles 4. The filter member 20 also carries out a control of the concentration slurry which is over a certain size as determined by the mesh of the screen.

In the construction indicated in FIG. 7, there is provided a sludge removal device generally designated 60. In this embodiment, parts which are similar to that of the other embodiments are similarly numerically designated but with the addition of a triple prime. In this construction, the shovel 7" is provided with a first stage mixing chamber 6" and a second stage chamber 66" which receives the slurry from the chamber 6" and which provides a further comminuting or pulverizing action on the sludge material. To obtain this action the apparatus includes a branch conduit 70 which connects to a ring conduit 72 having a plurality of nozzle elements 22 which whirl liquid into a tubular member 21 defining the chamber 66. The nozzles 22 provide water turning streams providing a whirling and breaking action on the sludge material to ensure that the whole mass is formed into a uniform slurry which is delivered through a flexible conduit 19. The turning chamber 66 ensures that the sludge will be delivered through the discharge connection 17" in a very fine form without any lumps.

What is claimed is:

l. A device for removing sludge particularly from the bottoms of oil tanks, comprising a shovel having a head defining an interior sludge receiving chamber with an opening which is adapted to be advanced into the sludge material to be removed, said shovel having an inclined bottom wall terminating in an engagement edge which is engageable into the sludge and with a wall inside said head defining an oblique impounding surface and a top wall with a front downwardly extending edge at the opposite side of the opening spaced forwardly of said bottom edge, nozzle means at said front edge including a nozzle oriented rearwardly toward said impounding surface for directing a high velocity jet of liquid downwardly against said impounding surface to loosen the sludge ahead of said bottom wall to permit it to enter into said receiving chamber to break up the sludge material and form it into a liquid slurry, discharge conduit means for the discharge of the slurry from said receiving chamber connected to said receiving chamber at a spaced location from the opening of said shovel head, and venturi means connected to said discharge conduit means to provide withdrawal pressure for moving the slurry through said discharge conduit means.

2. A device for removing sludge particularly from the bottoms of oil tanks, comprising a shovel having a head defining an interior sludge receiving chamber with an opening which is adapted to be advanced into the sludge material to be removed, said shovel having an inclined bottom wall terminating in an engagement edge which is engageable into the sludge and a top wall with a front downwardly extending edge at the opposite side of the opening spaced forwardly of said bottom edge, nozzle means at said front edge for directing a high velocity jet of liquid downwardly at a spaced location ahead of said bottom edge to loosen the sludge ahead of said bottom wall to permit it to enter into said receiving chamber to break up the sludge material and form it into a liquid slurry, discharge conduit means for the discharge of the slurry from said receiving chamber connected to said receiving chamber at a spaced location from the opening of said shovel head, and venturi means connected to said discharge conduit means to provide withdrawal pressure for moving the slurry through said discharge conduit means, said head including a screen extending across the interior thereof and defining an impounding surface against which the sludge material is received, said nozzle means including a nozzle directed to discharge against said screen.

3. A device, according to claim 2, wherein said nozzle means includes a nozzle mounted on said head, a

high pressure liquid conduit connected to said nozzle, conduit and being connected intermediate its length to said venturi means including a conduit at a remote losaid head at a location spaced from the opening cation from said head connected to said high pressure thereof.

liquid conduit, a diffuser surrounding one end of said

Claims

1. A device for removing sludge particularly from the bottoms of oil tanks, comprising a shovel having a head defining an interior sludge receiving chamber with an opening which is adapted to be advanced into the sludge material to be removed, said shovel having an inclined bottom wall terminating in an engagement edge which is engageable into the sludge and with a wall inside said head defining an oblique impounding surface and a top wall with a front downwardly extending edge at the opposite side of the opening spaced forwardly of said bottom edge, nozzle means at said front edge including a nozzle oriented rearwardly toward said impounding surface for directing a high velocity jet of liquid downwardly against said impounding surface to loosen the sludge ahead of said bottom wall to permit it to enter into said receiving chamber to break up the sludge material and form it into a liquid slurry, discharge conduit means for the discharge of the slurry from said receiving chamber connected to said receiving chamber at a spaced location from the opening of said shovel head, and venturi means connected to said discharge conduit means to provide withdrawal pressure for moving the slurry through said discharge conduit means.

3. A device, according to claim 2, wherein said nozzle means includes a nozzle mounted on said head, a high pressure liquid conduit connected to said nozzle, said venturi means including a conduit at a remote location from said head connected to said high pressure liquid conduit, a diffuser surrounding one end of said conduit and being connected intermediate its length to said head at a location spaced from the opening thereof.