JPH063895U - Sludge accumulation prevention device for oil tank - Google Patents

Abstract

(57) [Summary] [Object] To provide a sludge accumulation prevention device for an oil tank, which can effectively prevent accumulation of a significant portion of sludge accumulation even in an oil tank. [Structure] A nozzle 10 is provided in the vicinity of the bottom of the oil tank 1 in the circumferential direction of the tank to eject a co-oil into the stored oil to generate a swirl flow. And a discharge pipe 11 for discharging sludge at the center of the swirling flow.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sludge accumulation prevention device for an oil tank that prevents accumulation of sludge that precipitates from the oil in the oil tank, and in particular, an oil that can effectively prevent accumulation of a significant portion of sludge accumulation in the oil tank. It relates to a sludge accumulation prevention device for tanks.

[0002]

[Prior art]

 An oil tank for storing oil is generally composed of a skeleton that is formed in a cylindrical shape with a bottom with an open top to store the liquid storage, and a floating roof that floats above the liquid storage surface and can move up and down inside the skeleton. To be done.

When oil is stored in the oil tank, sludge precipitates from the oil and stays or accumulates at the bottom of the tank. The accumulated sludge hardens and deteriorates the storage efficiency of the oil tank. Therefore, the oil tank needs to remove the accumulated sludge.

Conventionally, in order to remove the sludge, after all the stored liquid has been discharged at the time of regular inspection, etc., a worker is put in the oil tank to perform the cleaning work. However, since cleaning work is so-called 3K labor that is tough, dirty, and dangerous, it tends to be avoided in recent years.

On the other hand, the oil tank is provided with a means for preventing the accumulation of sludge. To prevent sludge accumulation, either prevent sludge from settling or remove the sludge that has settled.

Conventionally, there is an oil tank provided with an electric mixer or a jet nozzle to prevent sludge from settling. Electric mixers and jet nozzles agitate the oil in the reservoir and prevent sludge settling. In addition, the oil tank equipped with such an electric mixer and jet nozzle is provided with a side discharge port for sludge removal. The side outlet is provided near the tank bottom on the outer periphery of the skeleton. Since the settled sludge can be discharged from the side discharge port, the accumulation of sludge can be prevented.

In addition, a base heater that heats the stored oil is provided in the oil tank that stores the oil having a high pour point, such as heavy oil. The base heater is a heater provided with a steam pipe formed in an annular shape or a hairpin shape concentric with the body near the bottom of the tank. The base heater warms the oil in the storage to improve the fluidity and generates convection to prevent the accumulation of sludge.

[0008]

[Problems to be solved by the device]

 A problem with the above-mentioned conventional sludge accumulation prevention device is that sludge is likely to stay in the central portion of the device equipped with the electric mixer and the jet nozzle. This is because when agitating with an electric mixer or jet nozzle, a flow of oil in the tank is generated that swirls in the tank in the circumferential direction. When a swirl flow occurs, sludge tends to collect at the center of swirl, that is, at the center of the tank. However, since the conventional side discharge port is provided on the outer periphery of the body, sludge collected in the center of the tank is not easily discharged from the side discharge port.

On the other hand, an oil tank provided with a base heater for heating has a problem that sludge is accumulated under the base heater. That is, the oil heated to about 60 ° C by the base heater can generate convection on the upper side of the base heater to obtain a stirring action, but almost no heat is generated on the lower side of the base heater because there is no convection. I can't get it. The bottom of the tank is in contact with the foundation and receives cold heat. For this reason, the oil near it loses its fluidity, for example, in winter, when it reaches about 15 ° C. Generally, the base heater is provided at a position of about 1 to 0.5 m from the bottom plate of the tank, so that sludge will be deposited within the range of 1 to 0.5 m.

Therefore, an object of the present invention is to solve the above problems and to provide a sludge accumulation preventing device for an oil tank, which can effectively prevent accumulation of a significant portion of sludge accumulation even in the oil tank.

[0011]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention is provided with a nozzle that is opened in the vicinity of the bottom of an oil tank in the circumferential direction of the tank and that ejects co-oil into the stored oil to generate a swirl flow. A discharge pipe is provided which has an opening at the center of the tank bottom and discharges the sludge at the center of the swirling flow.

Further, in an oil tank provided with a base heater for heating oil in the vicinity of the bottom of the oil tank, the tank corner bottom or bottom plate is faced between the base heater and the tank bottom, Nozzles for ejecting steam, high-temperature water, or high-temperature co-oil were arranged in the above.

[0013]

[Action]

 With the above configuration, a swirling flow is generated in the oil by the co-oil ejection from the nozzle, and the sludge gathers in the center. Since the opening of the discharge pipe is located in the center of the bottom of the tank, sludge collected in the center of the swirling flow is discharged.

Further, by injecting a high temperature co-oil from a nozzle provided between the base heater and the tank bottom, the oil near the tank bottom plate is heated and agitated, so that sludge is accumulated. To be prevented.

[0015]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 (a) and 1 (b) are a plan sectional view and a side sectional view of an oil tank equipped with a sludge accumulation prevention device according to the present invention.

As shown in FIG. 1, the oil tank 1 has a skeleton 2 having an open top and formed in a bottomed cylindrical shape. The skeleton 2 includes a side plate portion 3 and a bottom plate portion 4. The corner bottom portion 5 is composed of the above, and the vicinity where the side plate portion 3 and the bottom plate portion 4 are joined. A floating roof 6 that covers the upper opening is accommodated in the body 2. The floating roof 6 is provided so as to float above the liquid storage surface, and is vertically movable along the side plate portion 3. The floating roof 6 is provided with a plurality of roof supports 7 extending downward by a predetermined length. The roof support 7 is configured to hit the bottom plate portion 4 at a position where the floating roof 6 is most lowered.

A nozzle pipe 8 is provided below the lowermost position of the floating roof 6 so as to be inserted into the side plate portion 2 from the outside of the oil tank 1. The nozzle pipe 8 is connected to a pump 9 or the like, and the pump 9 is connected to the outside of the system such as another oil tank. At the end of the nozzle pipe 8 on the inner side of the tank, a nozzle 10 is attached, which extends a predetermined length with its opening facing the angle θ with respect to the radial direction of the tank. The nozzle 10 can generate a swirling flow by ejecting common oil into the stored oil. As shown in the figure, in this embodiment, the nozzles 10 are provided on both sides of the tank at an angle of approximately 25 ° with respect to the radial direction of the tank, which maximizes the sweeping effect.

A drain pipe 11 is provided at the bottom of the tank so as to be inserted into the side plate portion 2 from the outside of the oil tank 1. The discharge pipe 11 extends in the radial direction of the tank, and has an opening 12 facing the bottom plate 4 at the center of the tank bottom. The other end of the discharge pipe 11 is connected to the outside of the system such as another oil tank.

Next, the operation of the embodiment will be described.

By the function of the pump 9 or the like, the same type of oil as the main oil tank is introduced as co-oil from another oil tank outside the system. The common oil is ejected from the nozzle 10 into the oil. Since the nozzle openings are oriented in the circumferential direction, the swirling flow A is generated in the oil by the co-oil ejection from the nozzle 10. When the swirl flow A is generated in the oil, the sludge is attracted to the center and gathers near the center of the bottom plate 4. Since the opening 12 of the discharge pipe 11 is located at the center of the bottom of the tank, the sludge collected at the center of the swirling flow flows into the discharge pipe 11. In this way, the sludge is discharged from the discharge pipe 11.

Next, another embodiment will be described with reference to FIG. 2 (a) and 2 (b) are a plan sectional view and a side sectional view of the floating roof tank, respectively.

The floating roof tank 1a shown in FIG. 2 is composed of a skeleton 2 including side plate portions 3, bottom plate portions 4 and corner bottom portions 5 and a floating roof 6 as in the oil tank 1 described in FIG. There is. Oil having a high pour point such as heavy oil is stored in the skeleton 2.

FIG. 2B shows a state in which the floating roof 6 is at the most lowered position. The support 7 hits the bottom plate portion 4. A base heater 13 composed of a steam pipe formed in an annular shape concentric with the body 2 is provided at a position approximately 1 to 0.5 m above the bottom plate portion 4. The base heater 13 can warm the stored liquid by introducing steam of about 140 ° C. into the tube.

Between the base heater 13 and the bottom plate portion 4, a common oil pipe 14 formed in an annular shape concentric with the body 2 is provided. Although not shown, the common oil pipe 14 is supported by a support or the like from the bottom plate portion. The common oil pipe is connected to the pump outside the oil tank by the nozzle pipe 8. In this embodiment, the common oil pipe 14 is divided into two parts in a semi-annular shape, a lid plate is welded to each pipe end, and a nozzle pipe 8 is connected to each common oil pipe 14. There is. The pump can take out the same type of oil from another oil tank or the like and supply it to the common oil pipe 14 as common oil. This co-oil is supplied after being heated to a high temperature by a heater or the like. The common oil pipe 14 is provided with a large number of nozzles 15 at predetermined intervals. The nozzles 15 are inclined slightly outward or inward with respect to the circumference formed by the common oil pipe 14, and are arranged so that the nozzle openings are directed downward. Therefore, the ejection direction of each nozzle 15 faces the bottom 5 of the tank corner or the center of the bottom plate.

The common oil pipe 14 is configured so that a pipe for introducing high temperature water or steam can be connected in addition to the pipe from the pump.

During operation of the floating roof tank 1 a, when heating is performed by the base heater 13, high temperature co-oil is ejected from the nozzle 15. The ejection destinations of the nozzle 15 are the tank corner bottom portion 5 and the bottom plate portion 4 to which the heating of the base heater 13 does not reach. Therefore, the oil in the tank corner bottom portion 5 and the bottom plate portion 4 is heated and agitated, and the accumulation of sludge is prevented.

On the other hand, at the time of periodical inspection and the like, the stored liquid is discharged, the floating roof 6 is lowered most, and the roof support 7 hits the bottom plate portion. Here, common oil, high-temperature water, or water vapor is introduced into the common oil pipe 14. This common oil, high-temperature water or steam is used to wash the sludge ejected from the nozzle 15 and adhering to the tank corner bottom portion 5 and the bottom plate portion 4.

[0029]

[Effect of device]

 The present invention has the following excellent effects.

(1) It is possible to prevent the accumulation of a significant portion of sludge accumulation even in the oil tank, which effectively prevents sludge accumulation.

(2) The nozzle and co-oil pipe that prevent sludge accumulation during operation can be used for cleaning water during inspection, which is convenient.

[Brief description of drawings]

FIG. 1 is a plan sectional view and a side sectional view showing an embodiment of the present invention.

FIG. 2 is a plan sectional view and a side sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1 Oil tank 10 Nozzle 11 Discharge pipe

Claims (2)

[Scope of utility model registration request] 1. A nozzle is provided in the vicinity of the bottom of the oil tank in the circumferential direction of the tank, which is provided with a nozzle for ejecting co-oil into the stored oil to generate a swirling flow, and is opened at the center of the tank bottom. A sludge accumulation prevention device for an oil tank, comprising a discharge pipe for discharging sludge in the center of the swirling flow. 2. An oil tank having a base heater for heating oil near the bottom of the oil tank, wherein the base heater and the tank bottom face a tank corner bottom or a bottom plate between the base heater and the tank bottom. An apparatus for preventing sludge accumulation in an oil tank, characterized in that nozzles for ejecting steam, high temperature water, or high temperature co-oil are arranged.