US3527384A - Equipment and method for unloading liquids - Google Patents

Equipment and method for unloading liquids Download PDF

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Publication number
US3527384A
US3527384A US728277A US3527384DA US3527384A US 3527384 A US3527384 A US 3527384A US 728277 A US728277 A US 728277A US 3527384D A US3527384D A US 3527384DA US 3527384 A US3527384 A US 3527384A
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US
United States
Prior art keywords
tank
oil
liquid
unloading
auxiliary tank
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US728277A
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English (en)
Inventor
Susugu Koyama
Takeji Kyogoku
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Application granted granted Critical
Publication of US3527384A publication Critical patent/US3527384A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B27/00—Arrangement of ship-based loading or unloading equipment for cargo or passengers
    • B63B27/24—Arrangement of ship-based loading or unloading equipment for cargo or passengers of pipe-lines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D9/00—Priming; Preventing vapour lock
    • F04D9/04—Priming; Preventing vapour lock using priming pumps; using booster pumps to prevent vapour-lock
    • F04D9/06—Priming; Preventing vapour lock using priming pumps; using booster pumps to prevent vapour-lock of jet type
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/6851—With casing, support, protector or static constructional installations
    • Y10T137/6966—Static constructional installations

Definitions

  • Equipment for unloading liquids such as oil from oil tankers, is comprised of an auxiliary tank disposed near the bottom of the tank to be unloaded.
  • a piping system containing a jet pump connects the auxiliary tank and the tank to be unloaded.
  • Liquid flows from the tank into the auxiliary tank and is withdrawn by means of a main pump and discharged to another vessel or point of use.
  • the auxiliary tank is provided with control means for regulating the level of liquid within it which in turn regulates a control valve in the line discharging liquid from the main pump. Liquid can be bypassed from between the main pump and the discharge control valve and is used as the driving fluid for the jet pump.
  • the jet pump is used for completely unloading the liquid from the tank.
  • the present invention is directed to a method of and equipment for unloading liquid from a tank or a similar vessel and, more particularly, it is directed to an arrange ment for completely unloading the liquid from the tank.
  • Another object of the invention is to combine the use of a main centrifugal pump which alone performs the majority of the unloading operation with a jet pump which assists in completing the unloading operation when the liquid level drops to the lower part of the tank.
  • the liquid circulated by the main pump is employed to drive the jet pump.
  • the present invention is intended to overcome the various disadvantages which have been experienced in the past and to accord a method of and equipment for completely unloading liquid from a tank in a fast and efiicient operation.
  • a piping system including an auxiliary tank for effecting liquid-gas separation is located in the bottom of the ship roughly at the level of the bottom of the tanks to be unloaded.
  • a jet pump is positioned in the piping system between the auxiliary tank and the tank to be unloaded. When in use the jet pump is driven by a portion of the liquid discharged from a main pump and a by-pass line is provided from the discharge line from the pump to the jet pump.
  • the by-pass line contains a valve for controlling flow to the jet pump.
  • a control valve is disposed in the discharge line from the main pump and is operated by control means which regulate the level of the oil within the auxiliary tank.
  • an air discharge pipe is connected to the upper end of the auxiliary tank and extends upwardly opening to the atmosphere or into the upper end of the oil tank being unloaded.
  • an oil tanker is schematically illustrated containing a number of oil tanks 1 extending between an upper deck 2 and the bottom 4 of the ship with partition walls 3 separating the tanks.
  • a main pipe system .6 extends between the oil tanks to be unloaded and an auxiliary tank 9 wherein any gas mixed with the oil is separated from it.
  • a branch pipe 8 extends from the main pipe system 6 downwardly toward the bottom of the oil tank 1 and has a bell-mouthed inlet 7 located just above the bottom 4 of the ship through which the oil passes into the piping system.
  • the auxiliary tank 9 is connected to the main oil pump and a discharge line 12 extends from the pump 10 to another receiving vessel or point of use of the oil, not shown. Extending upwardly from the top of the auxiliary tank 9 is an air discharge pipe 11, the upper end of which is arranged to discharge into the atmosphere.
  • a control valve 13 is located in the discharge line 12 from the pump 10. Positioned between the pump 10 and the control valve 13 is the inlet to a by-pass line 14 which extends to a jet pump 16, of a known type, located in the main pipe system 6 between the branch pipe 8 and the auxiliary tank 9. In the by-pass line .14, a valve member is arranged to control flow to the jet pump 16.
  • Control means 17 are mounted on the auxiliary tank 9 to detect the level of oil within the tank and to adjust the control valve 13 for regulating the amount of oil passing through the discharge line 12, whereby the oil level within the auxiliary tank 9 can be maintained at a selected level.
  • the main pump 10 is employed in unloading the oil from the tanks 1, because the oil level within the auxiliary tank 9 is maintained at a suflicient level without utilizing the jet pump 16.
  • the main pump 10 withdraws the oil from the auxiliary tank 9 and discharges it to a point of use or storage through the discharge line 12.
  • the valve 15 in the by-pass line 14 is closed and the control valve 13 in the discharge line 12 is kept open.
  • the control means 17 are maintained in the off position and this may be accomplished by a manually operated switch, not shown. While this part of the unloading operation proceeds the jet pump merely acts as a part of the main pipe system 6 supplying the oil from the tanks 1 into the auxiliary tank 9.
  • the oil level within the auxiliary tank 9 is maintained at its predetermined height and the main pump 10 continues to work uninterruptedly because any gas or air in the auxiliary tank is discharged through the line 11.
  • the control means 17 is activated and the control valve 13 regulates the flow through the discharge line 12 so that a portion of the flow from the pump 10 passes into the by-pass line .14 and with the bypass valve member 15 opened, enters and drives the jet pump 16 for assisting in pumping out the bottom of the oil tanks 1.
  • the discharge pipe .11 opens to the atmosphere, it is more advantageous to locate the outlet from the discharge pipe in the upper end of the oil tank 1 since no problems will develop if the oil flows into the discharge pipe caused by any fluctuation in the oil level within the auxiliary tank.
  • the main pump is provided in the bottom of the ship and it is arranged to continue to operate for as long as possible during the unloading operations before the jet pump is placed in operation.
  • the jet pump Since the efliciency of the jet pump is inferior to that of the main pump, the longer the jet pump is used, the more will the efliciency of the overall unloading equipment decrease. Accordingly, though the jet pump is indispensable for completing the stripping operations within the individual tanks in the oil tanker, it is preferable to limit the extent to which it is required. If the auxiliary tank is positioned on the deck of the tanker the discharge pressure for the jet pump is increased and the operating load on it is increased. On the contrary if the auxiliary tank is positioned in the bottom of the tanker the discharge pressure on the jet pump is maintained at a low value and similarly its operating load is kept at a low value. Therefore, the efliciency of the overall equipment is reduced by only a small amount when the jet pump is operated.
  • the oil is circulated continuously through the main pump, the jet pump and the auxiliary tank, and though a considerable amount of air is drawn through the bell-mouthed inlet into the line supplying oil to the auxiliary tank the flow of oil continues until the stripping of the tank is completed and during this period the main pump does not receive any air from the auxiliary tank. Further, as soon as the unloading operation within one tank is completed the equipment can be switched to another tank without stopping.
  • the efliciency of the jet pump is considerably less than that of the main pump if the amount of use of the jet pump is limited, the overall efficiency of the unloading equipment will be greater. Therefore, by positioning the main pump, the jet pump, and the auxiliary tank at approximately the level of the bottom of the oil tanks in the tanker, the use of the jet pump can be limited to the greatest extent possible and the eificiency of the unloading equipment maintained at a maximum. Moreover, since the jet pump is only placed in operation when the level of the tank drops to a certain point during most of the unloading operation the capacity of the main pump is maintained at a high level.
  • the equipment in the present invention is simple in construction, it is low in manufacturing cost, it is easy to maintain, it is simple and safe in operation, and it requires little in the way of maintenance and repair. While the invention has been described with reference to an oil tanker it will be appreciated that it may be applied to unloading various types of liquids whether from a floating vessel or on land and can be used advantageously in a number of industries.
  • Liquid unloading equipment for pumping liquid, such as oil and the like, in a two-stage pumping operation from tanks wherein the tanks can be filled to a considerable height and the location of the tanks requires the liquid being unloaded to be lifted for approximately the height of the tanks in the unloading operation, comprising a conduit system for removing liquid from the tank to be unloaded and for supplying the liquid to an unloading station, an auxiliary tank is arranged in said conduct system exteriorly of the tank containing the liquid to be unloaded for separating gas from the liquid to be unloaded, said auxiliary tank having an inlet thereto and an outlet therefrom spaced above and in the vicinity of the bottom of the tank to be unloaded so that at least a major portion of the liquid to be unloaded when the tank is filled can fiow by gravity feed into said auxiliary tank, said conduit system comprising a first conduit and a second conduit, and first conduit connected to be the inlet to said auxiliary tank and extending into the tank to be unloaded for conveying the liquid into said auxiliary tank and having its opposite
  • Liquid unloading equipment as set forth in claim 1, wherein a gas discharge pipe is connected to the upper end of said auxiliary gas tank and extends upwardly therefrom for discharging gas separated from the liquid flowing through said auxiliary tank.
  • said first conduit comprises a branch conduit secured to said first conduit and extending downwardly therefrom Within the tank to be unloaded, and a bellmouth inlet member secured to the lower end of said branch conduit and being arranged to be positioned at the bottom of the tank to be unloaded.
  • a method of unloading liquid from a tank in a twostage unloading operation such as unloading oil from the tanks in an oil tanker and the like, where the liquid is lifted for the height of the tank in the unloading operation

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Loading And Unloading Of Fuel Tanks Or Ships (AREA)
  • Jet Pumps And Other Pumps (AREA)
  • Cleaning Or Clearing Of The Surface Of Open Water (AREA)
US728277A 1967-05-24 1968-05-10 Equipment and method for unloading liquids Expired - Lifetime US3527384A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3293467 1967-05-24

Publications (1)

Publication Number Publication Date
US3527384A true US3527384A (en) 1970-09-08

Family

ID=12372744

Family Applications (1)

Application Number Title Priority Date Filing Date
US728277A Expired - Lifetime US3527384A (en) 1967-05-24 1968-05-10 Equipment and method for unloading liquids

Country Status (5)

Country Link
US (1) US3527384A (enrdf_load_stackoverflow)
FR (1) FR1565965A (enrdf_load_stackoverflow)
GB (1) GB1226383A (enrdf_load_stackoverflow)
NL (1) NL6807425A (enrdf_load_stackoverflow)
SE (1) SE346280B (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4269619A (en) * 1976-05-14 1981-05-26 Kerr-Mcgee Chemical Corporation Ilmenite beneficiation process and a digester method
US4336763A (en) * 1973-11-01 1982-06-29 Wolff Robert C Marine vessel transfer system
US20140360058A1 (en) * 2011-12-22 2014-12-11 Ihc Engineering Business Limited Pump Apparatus and Underwater Trenching Apparatus
CN111664358A (zh) * 2020-05-18 2020-09-15 天津加马电潜泵有限责任公司 一种船用电泵的系统总成及其工作方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2651259A (en) * 1949-05-20 1953-09-08 Alanson P Brush Apparatus for controlling the operation of domestic water systems
US3128709A (en) * 1961-06-17 1964-04-14 G & J Weir Ltd System for pumping liquids into and out of tanks
US3253746A (en) * 1963-01-09 1966-05-31 Phs Van Ommeren N V Pumping system for tanks in ships

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2651259A (en) * 1949-05-20 1953-09-08 Alanson P Brush Apparatus for controlling the operation of domestic water systems
US3128709A (en) * 1961-06-17 1964-04-14 G & J Weir Ltd System for pumping liquids into and out of tanks
US3253746A (en) * 1963-01-09 1966-05-31 Phs Van Ommeren N V Pumping system for tanks in ships

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4336763A (en) * 1973-11-01 1982-06-29 Wolff Robert C Marine vessel transfer system
US4269619A (en) * 1976-05-14 1981-05-26 Kerr-Mcgee Chemical Corporation Ilmenite beneficiation process and a digester method
US20140360058A1 (en) * 2011-12-22 2014-12-11 Ihc Engineering Business Limited Pump Apparatus and Underwater Trenching Apparatus
US9719232B2 (en) * 2011-12-22 2017-08-01 Ihc Engineering Business Limited Pump apparatus and underwater trenching apparatus
CN111664358A (zh) * 2020-05-18 2020-09-15 天津加马电潜泵有限责任公司 一种船用电泵的系统总成及其工作方法

Also Published As

Publication number Publication date
FR1565965A (enrdf_load_stackoverflow) 1969-05-02
NL6807425A (enrdf_load_stackoverflow) 1968-11-25
DE1756458A1 (de) 1971-07-15
DE1756458B2 (de) 1973-01-04
SE346280B (enrdf_load_stackoverflow) 1972-07-03
GB1226383A (enrdf_load_stackoverflow) 1971-03-24

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