JPS59145684A - Discharger of slop tank liquid for chemical tanker - Google Patents

Abstract

PURPOSE:To uniform slop tank liquid efficiently by providing an agitation vane on the bottom of slop tank while providing a holed tube surrounding said vane and a convection promoting guide. CONSTITUTION:An agitation vane 22 journaled through a drive section 13 is provided on the bottom in the center of slop tank 7 while a holed tube 24 is provided while surrounding said vane 22 and a guide plate 27 for promoting convection is provided between tank wall and holed tube 24. Slop liquid having high specific gravity is moved upward by said agitation vane 22 to produce convection by the holed tube 24 and guide plate 27 thus to uniform slop efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention temporarily stores tank cleaning liquid that is generated when cleaning a chemical tanker tank in a slop tank.
The present invention relates to a homogeneous discharge device for slop tank liquid when the slop tank liquid is dumped in the open ocean.

Unlike oil tankers, chemical tankers are generally used to transport various types of chemicals, such as inorganic acids, alkaline liquids, and organic products such as molasses, in small quantities. After unloading the chemicals loaded in the chemical tank of the chemical tanker at the port, the chemical tanker cleans the inside of the tank and temporarily places it in a part of the ship's hull in order to load other types of chemicals in the next loading ditch. The cleaning water is stored in the slop tank,
After leaving the port, it will be dumped in the open sea! are doing. This washing water contains a large number of residual cargo chemicals, and if the cargo chemicals are water-insoluble, the remaining cargo, which is heavier than the washing seawater, will be at the bottom of the tank, the washing seawater will be in the middle, and the washing water will be at the top. It is often separated in a slop tank into multiple layers, such as three layers, of residual cargo that is lighter than seawater.

Regarding the ocean dumping of chemical cleaning water in recent years, international regulations regarding discharge methods, concentrations, discharge pumps used, flow rates, etc.
5 The MARPOL Treaty was concluded21. The regulations regulated by this treaty are expected to come into effect soon.

Therefore, when the cleaning liquid in the slop tank is dumped into the ocean, it is required to homogenize it by means such as stirring so that the concentration in the dumped liquid does not exceed the average concentration of 125 cm.

Conventionally, the devices shown in Figs. 1 and 2 have been used to meet the above requirements.
A homogeneous discharge system for the slop tank liquid of a chemical tanker as shown in the figure has been developed. Figure 1 is a schematic diagram of the homogeneous discharge device for the slop tank liquid;
The figure is a plan view of FIG. 1.

In FIGS. 1 and 21, a main body case 1 of the apparatus is placed inside a slop tank, and a cleaning liquid inflow opening 2 is bored in a part of the surface of the main body case 1 (in the area of the E-port). The liquid introduced through the 2 mm opening is stirred by the gentle rotation of a shaft 6 having six rotating blades 4.
A mechanism is provided for uniformly discharging the liquid through a discharge port 5 formed at the bottom and on the opposite side of the inflow opening 2. Busy: The homogeneous insect ejecting device requires a large amount of power to rotate the shaft 6 mentioned above, and requires a seal between the rotating blade 4 and the case 1, and generally a slot 1L.

As described above, in response to the demand for uniform discharge of slop tank liquid, the present invention was created as a result of research into a homogeneous discharge device that can replace the prior art.

The gist of the present invention is to provide an apparatus for storing liquid in a slop tank and discharging all of the liquid from the slop tank using a pump. A perforated cylinder is provided in the center and surrounds the stirring device, and a guide grate for promoting convection is provided between the tank wall and the perforated cylinder, and the slop tank liquid is discharged from the bottom of the tank.・/Located in the slop tank liquid discharge device of the Mikal tanker.

The present invention will be explained below based on examples.

FIGS. 6 and 4 are schematic diagrams showing a plane and side view of a chemical tanker, and FIGS. 5 and 6 are schematic diagrams for explaining a slop tank.

As shown in Figures 6 and 4, the slop tank 7 of a chemical tanker is usually the engine room 8 in the stern of the chemical tank.
Two tanks 21-C and 1o are the ballast tanks at the bow of the ship, with the pontoon bloom 9 sandwiched between them.

Therefore, the slop tank 7 as shown in FIGS.
A large longitudinal 12 is provided on the bottom of the ship for reinforcement in the bow and stern direction.
FIG. 1 is a schematic diagram of a slop tank on the starboard side as seen from arrow A in FIG. 1.

After the loaded chemicals in the chemical tank 6 are unloaded at the port, the inside of the chemical tank 6 is washed with overwater or warm seawater, and the washing liquid is pumped into the slop tank 7 (separately equipped, 1 The cleaning liquid in the transferred slop tank must be discharged after leaving the port to a homogeneous concentration, that is, within 125 cm of the average discharge concentration. Inside, the liquid is separated into three liquid layers: an upper liquid layer with a specific gravity lighter than seawater, an intermediate liquid layer with the same density as seawater, and a bottom liquid layer with a higher specific gravity than seawater.
Until then, it is not possible to discharge large quantities of homogeneous concentration.

Therefore, in order to achieve homogeneous discharge, it is necessary to mix the liquids, but in this case, the problem is how to mix the liquids that have a heavy specific gravity and a high liquid concentration at the bottom.

The present inventor solved the above problems by developing a homogeneous discharge device as shown in FIGS. 7 to 13.

FIG. 7 is a schematic diagram of a slop tank liquid homogenizing device of the present invention, and FIG. 8 is a schematic diagram showing a plan view of the slop tank liquid homogenizing device.

In FIGS. 7 and 8, a stirring device 16 is provided in the center of the slop tank 7, and the stirring device 16 has a motor 20 placed on the upper deck 14, and the motor shaft and the bottom 11 are connected to each other. The rotating shaft 21 is pivotally supported between the provided shaft bearings 23, 2t,
In addition, the rotating blade 22 is pivotally supported at the lower part of the rotating shaft 21, so that the configuration is IL. Further, in order to increase the stirring efficiency of the stirring blade 22, a perforated cylinder 24 as shown in FIG. 9 is provided surrounding the stirring blade 22 of the stirring device 13. No. 91□□
□ is a schematic diagram of a perforated cylinder 24, in which holes 25 are bored in the cylinder, and the number of holes and the degree of opening may be arbitrarily changed depending on the ratio of the separated liquid layer or the liquid quality. Furthermore tank wall 2
A guide plate 27 is welded between the cylinder 6 and the perforated cylinder 24 on the longitudinal 12 at the bottom of the entire tank, and the liquid in the 7t IJ tube rises due to the rotating blade 22. The liquid phase shown in the figure is stored in the longe 12 and has a large specific gravity, which is then effectively introduced to the stirring blade 22 and mixed homogeneously.

Another example is shown in FIG. 10 and prisoner 111.

No. 10111-j: In order to further improve the stirring efficiency, a low-head right conical or pyramidal nozzle 26 as shown in FIG. This is effective because it increases the convection force of the slop tank liquid, and allows the liquid with a heavy specific gravity to be homogeneously mixed by applying an upward force through the nozzle 26. Also the first
2 and 16 show other embodiments of the guide grating. In other words, Fig. 12 shows that when a slop tank is installed on the side as shown in Figs.
) The incoming liquid flow is guided along the longitudinal axis 12, and the chevron-shaped perforated guide grate 27' is connected to the tank wall 26 and the perforated cylinder 24.
It is preferable to provide the longitudinal 12 in between, taking into consideration the direction in which it is attached to the ship's bottom 11, to further achieve homogenization of the liquid.

After operation, the slop tank liquid is homogenized by a homogeneous mixing device with an upward configuration. After operation, the liquid is guided to the liquid quality monitor 28 through a sample collection tube from the bottom of the tank, and the target liquid quality is confirmed by the liquid quality monitor. After that, the pulp 29 is opened. It is dispersed and dumped into the sea below the water line 16 from a discharge nozzle 61 by a discharge pump 61 via a suction pipe 60. It is preferable that the satayon pipe 60 has a suction port facing downward and discharged at the bottom of the tank.

It is also possible to automatically control the operation of the discharge pump 61 and the valve 29 using the control signal from the liquid quality monitor 28.

The slop tank liquid discharge device of the present invention can mix and stir all of the slop tank liquid in the homogenizer, and since batch operation is the principle, reliable homogenization is possible in a short time, and it is possible to avoid dumping the slop tank liquid into the sea. This is a useful invention that fully complies with legal regulations.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of a conventional homogenized slop tank liquid discharge device, Figure 2 is a dry (cross-sectional) view of Figure 1, Figure 6 is a schematic diagram showing a side view of a chemical tanker, and Figure 4 is a schematic diagram of a side view of a chemical tanker. 6 is a schematic diagram showing a plane, FIG. 5 is a schematic diagram showing a side surface of a slop tank, FIG. 6 is a view taken in the direction of arrow A in FIG. 5, and FIG. 7 is a schematic diagram of a slop tank liquid homogenizing device of the present invention. , Fig. 8 is a schematic diagram showing the plane of Fig. 7, Fig. 9 is a schematic diagram of a cylinder with a hole, and Fig. 10'
The figure is a schematic diagram showing the positional relationship of a cylinder with a hole, a nozzle, and an impeller, FIG. 11 is a schematic diagram of a nozzle, FIG.
FIG. 3 is a schematic diagram for explaining the guide plate shown in the figure. 6...Chemical tank, 7...Slop tank, 1
DESCRIPTION OF SYMBOLS 1...Bottom, 12...Longi, 16...Agitator, 14...Upper deck, 20...Motor, 21...Rotating shaft) 22...Agitation blade, 24...Hole Bright cylinder, 25
．． 25...hole, 26...nozzle, 27.27'...
・Guide plate, 28...Liquid quality monitor, 60...
・Suction pipe, 61...Discharge pump, 62...
・Discharge nozzle. 483 Figure 1 Figure 2

Claims (1)

[Claims] In a device that uses a pump to discharge the slop tank liquid stored in the slop tank, the slop tank is
7. A stirring device having stirring blades is provided in the center of the tank, a perforated cylinder surrounding the stirring device, and a guide grate for promoting convection between the tank wall and the perforated cylinder are provided to control the slop tank liquid. A device for discharging liquid from a slop tank of a chemical tanker, which discharges liquid from the bottom of the tank.