CN111701964A

CN111701964A - Method and system for cleaning storage tanks using multiple devices

Info

Publication number: CN111701964A
Application number: CN202010176305.3A
Authority: CN
Inventors: 蔡瑞碘丹尼
Original assignee: Cai Yongcai International Ltd
Current assignee: Cai Yongcai International Ltd
Priority date: 2019-03-18
Filing date: 2020-03-13
Publication date: 2020-09-25
Also published as: PH12020050043A1; WO2020190209A1; SG10201902401YA

Abstract

The present invention relates to a method and system for cleaning storage tanks using multiple devices. The method includes positioning a first device at a first location of the storage tank; controlling the first device to move at the bottom and removing impurities at the bottom; connecting a second device to a second location of the storage tank; controlling the second device to move on an inner side wall and remove the impurities on the inner side wall; and controlling the first means to remove the foreign substances dropped on the bottom due to the second means removing the foreign substances on the inner sidewall.

Description

Method and system for cleaning storage tanks using multiple devices

The application claims priority of singapore patent with application number SG10201902401Y and application time of 2019, 3 and 18 months.

Technical Field

The present invention relates to a method and system for cleaning storage tanks using a variety of devices.

Background

The following discussion of the technical background is intended to facilitate an understanding of the present invention only. It should be noted that the discussion is not an acknowledgement or admission that any of the material referred to in the discussion was published, known or part of the common general knowledge of a skilled person in any jurisdiction as at the priority date of the invention.

Storage tanks are used in various industries to store various materials, such as petroleum, asphalt, and the like.

The storage tanks typically need to be cleaned or serviced periodically or for certain events. When inspecting the storage tank, it may be necessary to first perform cleaning in order for an inspector to inspect the storage tank. When the storage tank is damaged, it may need to be cleaned first to keep the storage tank free of steam for subsequent storage tank repair.

If a new product is planned to be stored that is different from the product originally in the tank, the tank may have to be cleaned. For example, if the product is converted from an unrefined product (e.g., bitumen/asphalt) to a refined product (e.g., diesel), thorough cleaning of the entire storage tank is required to remove impurities or undesirable particles, including debris, sludge, waste, contaminants, poisons, etc., from the bottom and side walls of the storage tank that the new product may directly contact to avoid any contamination of the new product.

Conventionally, cleaning the storage tanks requires manpower. Typically, such storage tanks can be up to several tens of meters in diameter and height. It is necessary to set up a scaffold or scaffolding for workers to clean the high side wall portion. When the side walls have been cleaned from the height, workers have to remove the scaffolding. In this respect, cleaning the storage tanks is time consuming and costly. Furthermore, since the worker must climb up the scaffolding to clean the high points of the side walls, there is a risk of the scaffolding collapsing and a safety hazard that the worker may fall from the scaffolding.

In view of the above, it is desirable to minimize the labor required to clean the storage tank. There is also a need to further provide solutions that meet the above needs or at least alleviate the above problems.

Disclosure of Invention

In this document, unless the context requires otherwise, the term "comprise" or variations such as "comprises" or "comprising", are intended to imply the inclusion of any stated integer or group of integers but not the exclusion of any other integer or group of integers.

Herein, unless the context requires otherwise, the term "comprise" or variations such as "comprises" or "comprising", are intended to imply the inclusion of any stated integer or group of integers but not the exclusion of any other integer or group of integers.

The present invention aims to provide a method of cleaning a storage tank with a minimum of manpower. The present disclosure provides a method of cleaning a storage tank using a plurality of devices (e.g., a first device and a second device). The device may include, but is not limited to, one or more of the following: a robot, a machine, a device and a vehicle.

The first device is used for cleaning the bottom of the storage tank, and the second device is used for cleaning the inner side wall of the storage tank. The first device may further be used to re-clean the bottom to remove impurities resulting from the operation of the second device. The first device and the second device are operable by a user via a remote control. The present invention thus enables cost and time savings and reduces the risks associated with conventional cleaning methods using manpower and scaffolding.

In one aspect of the present invention, there is provided a method of cleaning a storage tank using a plurality of devices, comprising: positioning a first device at a first location in the storage tank; controlling a first device to move at the bottom and remove impurities at the bottom; connecting a second device to a second location of the storage tank; controlling the second device to move on the inner wall and remove the impurities on the inner wall; controlling the first means to remove the impurities falling on the bottom due to the second means removing the impurities on the inner sidewall.

In some embodiments, the first location is on a surface proximate to a rim of the storage tank.

In some embodiments, the surface comprises the bottom and the inner sidewall.

In some embodiments, the second location is on the inner sidewall.

In some embodiments, the second means comprises at least one magnet to magnetically climb the inner sidewall.

In some embodiments, the second device comprises a water jet for rinsing the inner side wall to remove the impurities.

In some embodiments, the method further comprises a step of controlling the second device to remove stains caused by water mist generated by the water sprayer after the second device removes the impurities on the inner side wall.

In some embodiments, the second device is pneumatically operated.

In some embodiments, the method further comprises a step of providing a pump on the second device and controlling the pump to remove the impurities on the inner sidewall together with the second device.

In some embodiments, the pump comprises an ultra-high pressure (UHP) pump.

In some embodiments, at least one of the third and fourth means is disposed at the top of the storage tank.

In some embodiments, the method further comprises a step of spraying water inside the storage tank using the at least one of the third device and the fourth device.

In some embodiments, the method further comprises a step of spraying a chemical inside the storage tank using the at least one of the third and fourth devices to reduce the viscosity of the impurities.

In some embodiments, at least one of the third and fourth means comprises a nozzle operable to spray the chemical onto the inner side wall to flow the chemical to the bottom of the storage tank.

In some embodiments, the nozzle may be rotated at a predetermined angle at a predetermined time.

In some embodiments, the method further comprises a step of rotating the storage tank to allow the chemical to stir and react with the impurities.

In some embodiments, the method further comprises a step of disposing at least one filter tank outside the storage tank to capture at least a portion of the impurities pumped out during the rotation.

In some embodiments, the method further comprises a step of introducing the first device into the storage tank after the filtration tank captures the at least a portion of the impurities to remove residual impurities from the bottom.

In some embodiments, the method further comprises a step of introducing the second device into the storage tank to remove the residual impurities on the inner sidewall.

In some embodiments, the first device is introduced into the storage tank through a manhole in a sidewall of the storage tank by a lever.

In some embodiments, at least one of the plurality of devices is operated by a remote control.

In another aspect of the present invention, there is provided a system for cleaning a storage tank using a plurality of devices, comprising: a first device installed at a first position of the storage tank, configured to move at a bottom and remove impurities at the bottom; a second device connected to a second position of the storage tank and configured to move on an inner sidewall and remove impurities on the inner sidewall; wherein the first means is further operable to remove impurities falling to the bottom due to the second means when removing the inner sidewall impurities.

In some embodiments, the surface comprises the bottom or the inner sidewall.

In some embodiments, the second location is on the inner sidewall.

In some embodiments, the second device is configured to remove contaminants on the inner sidewall resulting from water mist from the water jet after removing the contaminants on the inner sidewall.

In some embodiments, the second device is pneumatically operated.

In some embodiments, a pump is provided in the second device, and the pump is controlled to remove impurities on the inner sidewall together with the second device.

In some embodiments, the pump comprises an ultra-high pressure (UHP) pump.

In some embodiments, the method further comprises a step of spraying water in the storage tank using the at least one of the third device and the fourth device.

In some embodiments, the at least one of the third and fourth means is disposed at the top of the storage tank.

In some embodiments, the method further comprises a step of spraying a chemical within the storage tank using the at least one of the third device and the fourth device to reduce the viscosity of the impurities.

In some embodiments, the at least one of the third and fourth devices includes a nozzle operable to spray the chemical onto the inner side wall to flow the chemical to the bottom of the storage tank.

In some embodiments, the storage tank may be rotated to allow the chemical to stir and react with the impurities.

In some embodiments, at least one filter canister is disposed outside the storage tank to capture at least a portion of the impurities pumped out of the storage tank during the rotation.

In some embodiments, the first means is introduced into the storage tank after the filtration tank captures the at least a portion of the impurities to remove residual impurities from the bottom.

In some embodiments, the second device is introduced into the storage tank to remove residual impurities on the inner sidewall.

In some embodiments, the first device is introduced into the storage tank through an access hole in a sidewall of the storage tank using a lever.

Other aspects of the disclosed subject matter will become apparent to those skilled in the art from a review of the following detailed description of the disclosed subject matter when taken in conjunction with the drawings.

Drawings

The technical solution of the invention will now be described, by way of example only, with reference to the accompanying drawings:

fig. 1-3 illustrate a method of cleaning a storage tank according to one embodiment of the present invention.

Fig. 4 and 5 illustrate a method of moving a first device according to one embodiment of the present invention.

Fig. 6-12 illustrate a method of cleaning a storage tank according to another embodiment of the present invention.

Figure 13 shows an example of how a vacuum truck and a waste bin with a powerful suction pump can be operated.

Fig. 14-18 illustrate a method of cleaning a storage tank according to another embodiment of the present invention.

Other arrangements of the presently disclosed subject matter are possible and, accordingly, the drawings are not to be taken as an alternative to the foregoing general description of the presently disclosed subject matter.

Detailed Description

In the manufacturing and/or distribution industry, it is often desirable to store products, such as materials, unrefined products, and/or refined products. The petroleum industry is one example. In the petroleum industry, products such as bitumen/asphalt, diesel, crude oil or gasoline are stored in storage tanks.

The present invention takes into account the need to clean the storage tank for various reasons. For example, if the product to be stored changes (e.g. from bitumen/asphalt to diesel), the storage tank needs to be thoroughly cleaned to avoid contamination of the new product.

As described above, conventionally, the manual operation is directly required when the storage tank is cleaned. In order to minimize the time and cost of cleaning storage tanks and eliminate the risks associated with conventional cleaning methods using manpower and racks or scaffolding, the present invention aims to provide a method of cleaning storage tanks using a variety of devices. These matters will be further explained with reference to fig. 1 to 18 below.

Fig. 1-3 illustrate a method of cleaning a storage tank 200 in accordance with one embodiment of the present invention.

The storage tank 200 includes, but is not limited to: an underground storage tank and an underground storage tank. In some embodiments, the storage tank 200 may be several tens of meters in diameter and height.

The apparatus 100 includes, but is not limited to: a robot, a machine, a device and a vehicle. As shown in fig. 1-3, the apparatus 100 may include a first apparatus 110 and a second apparatus 120.

In the storage tank 200, there is a contaminant 300 that needs to be removed. The impurities 300 may include undesirable particles such as sludge, waste, contaminants, poisons, and the like.

To clean the storage tank 200, the first device 110 may be introduced into the storage tank 200. Once the first device 110 is introduced into the storage tank 200, the first device 110 is installed at a first location of the storage tank 200. The first position may be on a surface proximate to a rim of the storage tank 200. The surface may comprise the bottom or an inner sidewall of the storage tank 200. For example, as shown in fig. 1, the first device 110 is located at the bottom of the storage tank 200. Thereafter, the first device 110 may move at the bottom and remove the impurities 300 from the bottom. For example, the first device 110 may be used to extract the impurities 300 from the bottom.

Although not shown, in some embodiments, the storage tank 200 further comprises one or more pipes above the bottom of the storage tank 200. For example, some pipes are located several inches or a foot above the bottom of the storage tank 200. In some embodiments, the first device 110 can remove the impurities 300 from the pipeline. In other embodiments, the user may remove the foreign matter 300 from the pipe.

In some embodiments, the first device 110 may include at least one camera, such as an explosion-proof camera, that may capture the cleaning status and record the cleaning status. The user can control the first means 110 to move on the bottom and suck out the foreign substances 300 outside the storage tank 200 while capturing a clean state using the camera. The user may control the first device 110 using a remote control. In some embodiments, the user may physically move to the manhole 210 to control or view the first device 110, if necessary.

In some embodiments, the first device 110 can include a water sprayer to clean the bottom to remove the impurities 300. For example, the first device 110 can spray water in various pressure ranges (e.g., up to 20000 psi). In other embodiments, the first device 110 is compatible with at least one external device (e.g., a pump and a sprinkler). The user can control the external device using the remote controller.

As shown in fig. 2, once the impurities 300 are removed from the bottom by the first device 110, the second device 120 may be introduced into the storage tank 200. Although not shown, it is understood that the second device 120 may be introduced into the storage tank 200 while the first device 110 is removing the impurities 300 from the bottom.

In some embodiments, the second device 120 can be carried by one or more users for introduction into the storage tank 200. For example, the second device 120 is about 62kg, and two users can carry the second device 120. The second device 120 is mounted in a second position. For example, the second position is located on an inner sidewall of the storage tank 200. In another example, the second location is at the bottom. The second device 120 is connected to an inner sidewall of the storage tank 200, and is movable on the inner sidewall to remove the impurities 300 from the inner sidewall. The second device 120 comprises at least one magnet, e.g., at least two magnetic tracks, and can magnetically climb the inner sidewall. For example, the magnetic force is sufficient to carry the weight of one or several users, such as one or two users.

In some embodiments, the second device 120 may comprise at least one camera, such as an explosion-proof camera, which may capture the cleaning status and record the cleaning status. The user can control the second device 120 to move on the inner sidewall from the outside of the storage tank 200 to suck the foreign substances 300, and at the same time, the user can monitor the cleaning state using a camera. The user may also control the second device 120 using a remote control.

In some embodiments, the user may detect the foreign matter 300 while manually moving the second device 120 on the inner sidewall to remove the foreign matter 300. Although not shown, in other embodiments, the second device 120 can detect the impurities 300 and automatically move on the inner sidewall to remove the impurities 300. In other embodiments, the second device 120 may move on the inner sidewall in a predetermined path and remove the impurities 300. In some embodiments, the second device 120 can include a water jet for cleaning the inner sidewall to remove the impurities 300. For example, the second device 120 can spray water at various pressure ranges (e.g., up to 36000psi) depending on the nature and/or cleaning status of the impurities. In some embodiments, to prevent the second device 120 from losing balance, the pressure of the second device 120 may be controlled to gradually increase or decrease.

In some other embodiments, the second device 120 can be compatible with external devices (e.g., pumps and sprinklers). The user can control the external device using the remote controller. For example, the user may set the pump on the second device 120 and control the pump to remove the foreign substances 300 on the inner sidewall together with the second device 120. The pump may include, but is not limited to: an ultra-high pressure (UHP) pump 121 (not shown). The UHP pump 121 is operable with the second device 120 to remove the impurities 300 on the inner side wall. The UHP pump 121 may pump water onto the second device 120 to remove the impurities 300.

The UHP pump 121 can operate at various pressure ranges (e.g., 10000 to 40000psi), depending on the nature and/or cleaning status of the impurities. In some embodiments, if the impurities 300 to be removed are harder and more tenacious, such as a solid paint, the UHP pump 121 can be operated at high pressure to remove the solid paint. As another example, if the impurities 300 remaining on the inner sidewall are less, the UHP pump 121 may be operated at a low pressure. In some embodiments, the change in pressure range can be accomplished by replacing a transition fitting of the plunger of the UHP pump 121.

In some embodiments, to prevent the second device 120 from losing balance, the pressure of the UHP pump can be controlled to gradually increase or decrease.

When the second device 120 removes the impurities 300 on the inner sidewall, the water mist of the sprinkler may generate stains. The second device 120 is further operable to remove the stain caused by the water mist. Thus, the second device 120 may be deployed to clean the inner sidewall twice.

In some embodiments, the second device 120 may be pneumatically operated and thus adapted to operate in a confined space environment such as the storage tank 200. The second device 120 can be safely operated because there is no risk of a short circuit.

Although not shown, in some embodiments, the storage tank 200 may include one or more columns and/or one or more internal pipes therein. The user may manually clean the columnar structure and/or the conduit using a water spray.

Although not shown, in some embodiments, the storage tank 200 further comprises one or more outlets, such as within the interior of the column and/or pipe. These outlets are also contaminated by the impurities 300. For example, the impurities 300 may be flushed using a High Pressure (HP) pump (not shown) to clean the outlet. For example, the HP pump may have a pressure of up to 20000 psi. The HP pump may include at least one flushing nozzle to flush the impurities 300 at the outlet. The nozzle may be connected to a hose and inserted into the column and/or pipe. In some embodiments, a sprayer may be used to flush the impurities 300 when the depth of the outlet is below a predetermined depth. The liquid spray may comprise a spray gun for hydraulic spraying. The sprayer can be connected to the HP pump and/or UHP pump and manually operated by the user.

The water pressure required by the HP pump may depend on one of the depth of the outlet, the nature of the impurities 300 or the amount of the impurities 300.

Although not shown, the second device 120 may be removed from the storage tank 200 after the impurities 300 are removed from the inner sidewall. In some embodiments, the user may detach the second device 200 from the inner sidewall and remove the second device 200 from the storage tank 200. In some embodiments, the user can control the second device 120 to reduce the magnetic force to easily detach the second device 200 from the inner sidewall.

When the second device 120 removes the foreign substances 300 from the inner sidewall, some of the foreign substances 300 fall on the bottom of the storage tank 200. Thus, final cleaning can be performed. As shown in fig. 3, the first device 110 may be used to remove the impurities 300 at the bottom. The impurities 300 further comprise products from water mist produced by the water spray. For example, the first device 110 may be used to extract the impurities 300.

Although not shown, in some embodiments, the first device 110 may further be used to remove the impurities 300 from the low-lying pipes and/or columns of the storage tank 200.

Fig. 4 and 5 are a method of moving the first device according to one embodiment of the present invention.

As shown in fig. 4, the storage tank 200 includes at least one manhole 210. For example, the manhole 210 may be positioned on a sidewall of the storage tank 200. Although not shown, the manhole 210 may be covered by a cover. It is understood that the manhole 210 is covered by the cover when the storage tank 200 stores a product.

After removing the cover from the manhole 210, the first device 110 may be introduced into the storage tank using a lever 211. The lower side of the manhole 210 may serve as a fulcrum of the lever 211. The center of the lever 211 may be placed at a lower side of the manhole 210 so that one side of the lever 211 may be placed inside the storage tank 200 and the other side of the lever 211 may be placed outside the storage tank 200. Then, the first device 110 is positioned at the other side of the lever 211. A force is applied to one side of the lever 211 so that the lever 211 tilts and raises the first device 110. The tilting of the lever 211 introduces the first device 110 into the storage tank 200.

In some embodiments, the first device 110 may be removed from the storage tank 200 at a predetermined time (e.g., at the end of each day of work). The storage tank 200 may be covered or boxed to prevent fumes or vapors from escaping during the night. In some other embodiments, the lever 211 may be used to carry the first device 110 away from the storage tank 200 after the first device 110 removes the impurities 300 remaining at the bottom and the final cleaning is completed. As shown in fig. 5, a lower side of the manhole 210 may serve as a fulcrum of the lever 211. The center of the lever 211 may be placed at a lower side of the manhole 210 so that one side of the lever 211 may be located inside the storage tank 200 and the other side of the lever 211 may be located outside the storage tank 200. Then, the first device 110 is disposed at one side of the lever 211. A force is applied to the other side of the lever 211 so that the lever 211 tilts and raises the first device 110. The tilting of the lever 211 causes the first device 110 to be removed from the storage tank 200.

Fig. 6-12 illustrate a method of cleaning the storage tank 200 according to another embodiment of the present invention.

Figure 13 is an example showing how a vacuum truck and a waste bin with a powerful suction pump can operate.

As shown in fig. 6 to 9, the apparatus 100 may further include at least one of a third apparatus 130 and a fourth apparatus 140. At least one of the third device 130 and the fourth device 140 may be used with the first device 110 and the second device 120 to clean the storage tank 200. The use of the third device 130 and/or the fourth device 140 may be determined according to the size of the storage tank 200. For example, if the size of the storage tank 200 is greater than a predetermined size, the third device 130 may be used. The fourth device 140 may be used if the size of the storage tank 200 is smaller than a predetermined size.

In this manner, the third device 130 and/or the fourth device 140 may be used to clean the storage tank 200. In particular, one or both of the third device 130 and the fourth device 140 may be used together to clean the storage tank 200. It is understood that either or a combination of the third device 130 and the fourth device 140 may be used to clean the storage tank 200.

For example, the third device 130 or the fourth device 140 may be disposed at the top of the storage tank 200. As shown in fig. 6 and 8, the third device 130 or the fourth device 140 may be hung on the top of the storage tank 200. The third device 130 or the fourth device 140 may be hung in the center of the top of the storage tank 200 so that the

chemicals

131, 141 can reach the entire inner sidewall.

As another example, although not shown, both the third device 130 and the fourth device 140 are disposed together at the top of the storage tank 200. As another example, the third device 130 and the fourth device 140 may be hung on the top of the storage tank 200.

Although not shown, one or more third devices 130 and/or one or more fourth devices 140 may be used to clean the storage tank 200. In particular, for example, a plurality of third devices 130 may be used to clean the storage tank 200. In another example, a plurality of fourth devices 140 may be used to clean the storage tank 200. In another example, a single third device 130 may be used with a plurality of fourth devices 140 to clean the storage tank 200. In another example, a plurality of third devices 130 may be used with a single fourth device 140 to clean the storage tank 200. In another example, a plurality of third devices 130 and a plurality of fourth devices 140 may be used together to clean the storage tank 200.

In some other embodiments, the third device 130 and/or the fourth device 140 may be in the form of a vehicle, for example, may be a flying unmanned vehicle, such as a drone. It is understood that when the third device 130 and/or the fourth device 140 sprays the

chemicals

131, 141, the storage tank 200 may be closed and sealed, and the manhole 210 may be covered with a cover.

As shown in fig. 7, the third device 130 may include a container 132 for holding chemicals 131 and a self-rotating nozzle (also referred to as a "tip") 133 for spraying the chemicals 131 onto the inner sidewall so that the chemicals 131 flow down to the bottom of the storage tank 200. The self-rotating nozzle 133 may be rotated at a prescribed angle at a prescribed time. In some embodiments, the self-rotating nozzle 133 may be automatically rotated at a prescribed angle at a prescribed time. In some other embodiments, a user may control the self-rotating nozzle 133 to rotate at a specific angle at a specific time. The user may also control the third device 130 using a remote control.

As shown in fig. 9, the fourth device 140 may include a container 142 for holding the chemical 141 and at least one nozzle 143, for example, four (4) nozzles, for spraying the chemical 141 onto the inner sidewall such that the chemical 141 flows down to the bottom of the storage tank 200.

In some embodiments, the angle between the

containers

132, 142 and the

nozzles

133, 143 in the third device 130 and/or the fourth device 140 is 90 °. This arrangement may allow for cleaning of the light industrial products and/or

spray chemicals

131, 141 in the storage tank 200 without the need for human labor. In this case, the third device 130 and/or the fourth device 140 may preliminarily wash the bottom and the inner sidewall of the storage tank 200. Accordingly, the third device 130 and/or the fourth device 140 may allow the first device 110 and the second device 120 to easily remove the impurities 300.

The

chemicals

131, 141 may be materials that can react with the impurities 300. The user may select the

chemicals

131, 141 suitable for cleaning the storage tank 200 according to the nature of the impurities 300. In some embodiments, the

chemicals

131, 141 are a light yellow viscous but pourable liquid, with a slightly nutty taste. The

chemicals

131, 141 may be mixed with a non-ionic surfactant. The

chemicals

131, 141 can be used as a major component in petroleum remediation activities for soil remediation or as a base component in surface cleaners and degreasing systems. In some other embodiments, the

chemicals

131, 141 are light yellow formulated liquids with a slight citrus odor. The

chemicals

131, 141 may be formed by mixing a nonionic surfactant and a solvent. The

chemicals

131, 141 can be used as cleaning products for removing light tar and grease deposits or as general cleaning agents.

The impurities 300 may react with the

chemicals

131, 141. In this regard, the

chemicals

131, 141 may reduce the viscosity of the impurities 300, thereby enabling the impurities 300 to be pumped out. In this case, the foreign substances 300 can be easily removed without manually discarding the foreign substances 300 in the storage tank 200.

In some embodiments, the

chemicals

131, 141 may be used with other chemicals. For example,

chemicals

131, 141 may be used with biodiesel in a 1:4 ratio. In this regard, the

containers

132, 142 may hold a mixture of

chemicals

131, 141 and biodiesel. In some embodiments, the

chemicals

131, 141 may inhibit vapor within the storage tank 200 when the biodiesel or diesel reacts with the

chemicals

131, 141.

In this manner, the third device 130 and/or the fourth device 140 can at least reduce the viscosity of the impurities 300 in the storage tank 200. When the

chemicals

131, 141 react with the impurities 300, the impurities 300 become able to be pumped out, and thus the impurities 300 can be easily removed. Accordingly, the third device 130 and/or the fourth device 140 may allow the first device 110 and the second device 120 to easily remove the impurities 300.

After the third means 130 and/or the fourth means 140

spray chemicals

131, 141 into the storage tank 200, a loop is established inside and outside the storage tank 200. In one example, the cycling process may take about two weeks. Although not shown, in some embodiments,

more chemicals

131, 141 or a mixture of

chemicals

131, 141 and biodiesel may be introduced into the storage tank 200 during the cycle.

Air is circulated in the storage tank 200 to assist in venting the vapor to the atmosphere. Although not shown, one or more ventilation fans are installed to some of the manholes to remove air from the storage tank 200. Air from the outside will automatically enter the storage tank 200 from other manholes by the operation of the fan.

Although not shown, the impurities 300 after reaction with the

chemicals

131, 141 may be discharged using a vacuum truck or a high power suction pump. Since the impurities 300 after reaction can be pumped out, a vacuum truck or a high power suction pump can pump out the impurities 300 during the circulation.

After the third device 130 and/or the fourth device 140 flushes the storage tank 200, the first device 110 and the second device 120 may be introduced into the storage tank 200 to remove the impurities 300. As shown in fig. 10-12 below.

As shown in fig. 10, the first device 110 may be introduced into the storage tank 200 and disposed at the first location of the storage tank 200, for example, at the bottom. Thereafter, the first device 110 may move at the bottom and remove the impurities 300 from the bottom. Since the third device 130 and/or the fourth device 140 preliminarily flush the bottom of the storage tank 200, the first device 110 may concentrate on removing the harder and more stubborn impurities 300 that are not removed by the third device 130 and/or the fourth device 140. Thus, the first device 110 is capable of spraying water over a range of pressures suitable for removing the harder and more stubborn impurities 300.

As shown in fig. 11, the second device 120 may be introduced into the storage tank 200 and connected to the second location of the storage tank 200, for example, on the inner sidewall. The second device 120 may move on the inner sidewall and remove the impurities 300 on the inner sidewall. The second device 120 can climb the inner sidewall by magnetic force. Since the third device 130 and/or the fourth device 140 preliminarily washes the inner sidewall of the storage tank 200, the second device 120 may concentrate on removing the harder and more stubborn impurities 300 that are not removed by the third device 130 and/or the fourth device 140. Therefore, the UHP pump 121, which is arranged on said second device 120, is able to spray water within a pressure range suitable for removing said harder and more stubborn impurities 300.

When the second device 120 removes the impurities 300 from the inner sidewall, some of the impurities 300 fall to the bottom of the storage tank 200. Therefore, a final cleaning is required. As shown in fig. 12, the first device 110 may be used to remove the impurities 300 at the bottom. The impurities 300 further may include products resulting from water mist caused by the water spray.

Although not shown, in some embodiments, the first device 110 may further be used to remove the impurities 300 from the low-lying pipes and/or columnar structures of the storage tank 200.

As shown in fig. 13, in some embodiments, the impurities 300 flushed by the third device 130 and/or the fourth device 140 may be removed using a vacuum truck 410 or a high power suction pump 420 of a trash bin 430 before the first device 110 and the second device 120 are introduced into the storage tank 200.

Since the third device 130 and/or the fourth device 140 preliminarily washes the bottom of the storage tank 200 and the impurities 300 washed down have been removed by the vacuum truck 410 or the powerful suction pump 420, the first device 110 may concentrate on removing the harder and more stubborn impurities 300 that are not removed by the third device 130 and/or the fourth device 140. In addition, since the third device 130 and/or the fourth device 140 preliminarily washes the inner sidewall of the storage tank 200 and the washed foreign substances 300 have been removed by the vacuum truck 410 or the high power suction pump 420, the second device 120 may concentrate on removing the harder and more stubborn foreign substances 300 that are not removed by the third device 130 and/or the fourth device 140.

Fig. 14 to 18 show a method of cleaning a storage tank 200 according to another embodiment of the present invention.

As shown in fig. 14 and 15, the apparatus 100 may further include the third apparatus 130 and/or the fourth apparatus 140. The third device 130 and/or the fourth device 140 may be used with the first device 110 and the second device 120 to clean the storage tank 200. Although not shown in fig. 14-18, the third device 130 and/or the fourth device 140 may be used with the first device 110 and the second device 120.

As shown in fig. 14 and 15, at least one filter tank 240 may be provided outside the storage tank 200 to filter and capture the foreign substances 300 pumped out by the first pump 231 during circulation. Therefore, the foreign substances 300 pumped by the first pump 231 may be removed from the storage tank 200. In some embodiments, the second pump 232 may send the

chemicals

131, 141 back to the third device 130 and/or the fourth device 140.

When the pumped foreign substances 300 are regarded as having been removed by the filter tank 240, the foreign substances 300 remaining inside the storage tank 200 may be removed. Since the remaining impurities 300 are harder and more persistent, a powerful pump may be required to remove the remaining impurities 300 from the storage tank 200.

At this stage, as shown in fig. 16, the first device 110 may be introduced into the storage tank 200 to perform a suction work at a different position of the bottom of the storage tank 200. The first device 110 may move at the bottom and remove the residual impurities 300 at the bottom. Since a portion of the impurities 300 have been removed by the filter canister 240, the first device 110 may focus on removing the harder and more stubborn impurities 300 that were not removed by the filter canister 240. Thus, the first device 110 is capable of spraying water over a range of pressures suitable for removing the harder and more stubborn impurities 300.

Although not shown, in some embodiments, the storage tank 200 further comprises one or more pipes above the bottom of the storage tank 200. For example, some pipes are located several inches or a foot above the bottom of the storage tank 200. These conduits may be cleaned by the first device 110. In another example, these conduits may be cleaned by a user when the second device 120 cleans the interior sidewalls or after the second device 120 cleans the interior sidewalls. Most of the stain has been removed by the

chemicals

131, 141.

As shown in fig. 17, the second device 120 may be introduced into the storage tank 200. In some embodiments, the second device 120 may be introduced into the storage tank 200 after the first device 110 removes the residual impurities 300 from the bottom. In some other embodiments, the second device 120 may be introduced into the storage tank 200 while the first device 110 is removing the residual impurities 300 at the bottom.

The second device 120 may be connected to the inner sidewall of the storage tank 200. The second device 120 may move on the inner sidewall and remove the impurities 300 on the inner sidewall. The second device 120 can climb the inner sidewall by magnetic force. Since at least a portion of the impurities 300 have been removed by the filter canister 240, the second device 120 may focus on removing the harder and more tenacious impurities 300 that were not removed by the filter canister 240.

In some embodiments, the UHP pump 121 disposed on the second device 120 is capable of spraying water at a pressure range suitable for removing harder and more stubborn impurities 300. The water spray may remove remaining impurities 300, such as residue, on the inner sidewall.

Although not shown, in some embodiments, the storage tank 200 further comprises one or more outlets, such as within the interior of the column and/or pipe. These outlets are also contaminated with impurities 300. For example, the impurities 300 may be flushed using a High Pressure (HP) pump (not shown) to clean the outlet. The HP pump may include at least one flushing nozzle to flush the impurities 300 at the outlet. The nozzle may be connected to a hose and inserted into the column and/or pipe. In some embodiments, when the depth of the outlet is below a predetermined depth, a sprayer may be used to flush the impurities 300.

The water pressure required by the HP pump may depend on the depth of the outlet and the nature and/or quantity of the impurities 300. In some embodiments, the impurities 300 at the outlet may come into contact with the

chemicals

131, 141, thereby becoming easily removed. In this regard, high water pressure may no longer be required. For example, the required water pressure may be less than 10,000 psi.

When the second device 120 removes the foreign substances 300 from the inner sidewall, some of the foreign substances 300 drop on the bottom of the storage tank 200. Thus, final cleaning can be performed. As shown in fig. 18, the first device 110 may be used to remove impurities 300 that have fallen to the bottom. The impurities 300 further may include products resulting from water mist caused by the water spray.

Although not shown, in some embodiments, the first device 110 may further be used to remove impurities 300 from the low-lying channels and/or columnar structures of the storage tank 200.

To prevent any contamination that may subsequently occur, the storage tank 200 needs to be properly cleaned. As depicted in fig. 14-18, most of the impurities 300 may be removed from the inner walls of the storage tank 200 using

chemicals

131, 141. The

chemicals

131, 141 may reduce the viscosity of the impurities 300, thereby allowing the impurities 300 to be easily pumped without the need for manual or equipment removal. Because, at normal and room temperature, the impurities 300 continue to remain in a liquid state after reaction with the

chemicals

131, 141, at least until cleaning of the storage tank 200 is completed.

Further, since the steam is caused by the product in the storage tank 200, it is necessary to suppress the steam in the storage tank 200. Such products (vapors) may have a low ignition point (i.e., a temperature that would ignite a flame) and the pressure of such vapors may initiate a fire and/or explosion. It is also desirable to have the storage tank 200 in a gas-free state to allow personnel access (inspection, etc.) at a later time. The

chemicals

131, 141 may inhibit the vapor in the storage tank 200.

Those skilled in the art will appreciate that variations and combinations of the above-described features, which are not alternatives or alternatives, may be combined to form further embodiments within the scope of the invention.

Claims

1. A method of cleaning a storage tank using a plurality of devices, the method comprising the steps of:

positioning a first device at a first location of the storage tank;

controlling the first device to move at the bottom and removing impurities at the bottom;

connecting a second device to a second location of the storage tank;

controlling the second device to move on the inner side wall and remove the impurities on the inner side wall;

controlling the first means to remove the impurities falling to the bottom due to the second means removing the impurities on the inner sidewall.

2. The method of claim 1, wherein the first location is on a surface proximate to a rim of the storage tank.

3. The method of claim 2, wherein the surface comprises the bottom and the inner sidewall.

4. The method of claim 1, wherein the second device is located on the inner sidewall.

5. The method of claim 1, wherein the second device comprises at least one magnet to magnetically climb the inner sidewall.

6. The method of claim 5, wherein the second device comprises a water jet for rinsing the inner sidewall to remove the impurities.

7. The method of claim 6, wherein the method further comprises a step of: controlling the second device to remove the stain caused by the water mist generated by the water sprayer after the second device removes the impurities on the inner side wall.

8. The method of claim 6, wherein the second device is operated pneumatically.

9. The method of claim 5, wherein the method further comprises a step of: and arranging a pump on the second device, and controlling the pump and the second device to remove the impurities on the inner side wall.

10. The method of claim 9, wherein the pump comprises an Ultra High Pressure (UHP) pump.

11. The method of claim 1, wherein at least one of a third device and a fourth device is disposed at a top of the storage tank.

12. The method of claim 11, wherein the method further comprises a step of: spraying water inside the storage tank using the at least one of the third device and the fourth device.

13. The method of claim 11, wherein the method further comprises a step of: spraying a chemical inside the storage tank using the at least one of the third and fourth devices to reduce the viscosity of the impurities.

14. The method of claim 13, wherein said at least one of said third device and said fourth device comprises a nozzle operable to spray said chemical onto said inner sidewall to flow said chemical to said bottom of said storage tank.

15. The method of claim 14, wherein the nozzle is rotatable at a predetermined angle at a predetermined time.

16. The method of claim 13, wherein the method further comprises a step of: rotating the storage tank to allow the chemical to stir and react with the impurities.

17. The method of claim 16, wherein the method further comprises a step of: disposing at least one filter canister outside the storage tank to capture at least a portion of the impurities pumped out during the rotation.

18. The method of claim 17, wherein the method further comprises a step of: introducing the first device into the storage tank to remove residual impurities from the bottom after the filtration tank captures the at least a portion of the impurities.

19. The method of claim 18, wherein the method further comprises a step of: introducing the second device into the storage tank to remove the residual impurities on the inner sidewall.

20. The method of claim 1, wherein said first means is introduced into said storage tank through a lever through an access opening in a sidewall of said storage tank.

21. The method of claim 1, wherein at least one of the plurality of devices is operated by a remote control.

22. A system for cleaning a holding tank using a plurality of devices, comprising:

1) a first device located at a first location of the storage tank and configured to move and remove impurities at the bottom;

2) a second device connected to a second position of the storage tank and configured to move on an inner sidewall and remove impurities on the inner sidewall;

3) wherein the first means is for removing the foreign substances dropped on the bottom due to the second means removing the foreign substances on the inner sidewall.