ES2578953T3 - Use of a cleaning fluid to clean a fluid transport apparatus and a cleaning fluid - Google Patents

Abstract

Use of a cleaning fluid (12, 112) to clean a fluid transport apparatus (10) in which, outside or through it a fluid can flow, the cleaning fluid (12, 112) comprises: a volume of liquid (14, 114) and fiber particles (16, 124) comprising paper fibers, or fiber particles derived from newspaper and / or paper, the cleaning fluid (12, 112) has low viscosity and comprises fiber particles distributed in the volume of liquid (14, 114) in an amount that does not exceed the transport capacity of the particles of that volume of liquid and has sufficient fiber particles (16, 124) distributed in the volume to provide a cleaning action during use, the cleaning action comprises additional particles (18, 118) collected and transported together with the cleaning fluid in the volume when the cleaning fluid (12, 112) flows through the fluid transport apparatus (10) .

Description

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DESCRIPTION

Use of a cleaning fluid to clean a fluid transport apparatus and a cleaning fluid

The present invention relates to the use of a cleaning fluid to clean a fluid transport apparatus. In a particular embodiment, the invention provides a cleaning fluid.

A fluid transport apparatus, such as fluid transport tubes, storage tanks or containers, are widely known for use in a number of industrial applications. In road constructions, materials may have to be transported from a storage location to a place on the road where it may be necessary to build a road surface. In the gas and oil industry, an apparatus in the form of tubenas is used to move hydrocarbon products between locations, often separated over long distances. In addition, oil and recovered gas are typically transported by a sequence of sections of tubena as they are pumped from the well, in the installation of the well, and in the tubena for export to a refinery. In addition, the recovered hydrocarbons can be treated in a well installation or a refinery where the product can also be moved through different types of tanks, for example, separation tanks to separate different gases, or light and heavy oils.

Therefore, in the production of oil and gas, a hydrocarbon product will typically be passed through numerous pipe systems.

Over time, unwanted residues, waxes and dirt can accumulate inside the fluid transport apparatus. The solids that can be transported together with the fluid can fall and deposit inside the apparatus, and some substances can even get to adhere to the internal surfaces of said apparatus.

These unwanted particles and residues can contaminate a product that passes through a pipeline, and after a long period of accumulation can adversely affect the performance of a pipeline system. Therefore, it is convenient to periodically remove these partroulas and waste to clean the system. It may also be convenient to treat a cleaning system with a coating to protect and resist the accumulation of such waste.

Therefore, occasionally, the interiors of such tuben systems need to be cleaned to remove residues adhered to the internal surfaces of the pipe system and to collect loose deposits that settled from the fluid, and be treated with protective coatings.

There are a number of difficulties that arise in order to clean such systems. For example, a problem is how to access the inner surfaces of the fluid transport apparatus. An additional difficulty is how to carry out cleaning and / or treatment effectively.

At present, the cleaning and treatment of tubenas is often carried out through the use of Tube Inspection Calibrators (pigs), which are pumped through a tubena. The pigs can be equipped with brushes or scrapers that extend to interact with the inner surfaces of the tubena to remove the material. The material removed from the walls of the tubena or deposited in the tubena is pressed along the tubena in front of the pig and removed at an additional access point along the tubena. Other elements can be used to coat a tubena wall.

The pig technique has significant drawbacks. One difficulty is that the pig is designed with a specific diameter to fit a tubena section with a corresponding diameter. Thus, any pig cannot be adapted for cleaning or treatment when the tubena diameter changes along its length, or when the tubena is transferred to other types of fluid transport apparatus, such as tanks, in other parts of the system . Therefore, Pigs are likely to get stuck in a tubena. This can be a particular problem when any rest is present in the tubena.

In addition, because the pigs have limited dimensions, the cleaning and / or treatment elements may not be effective in accessing and cleaning the cavities, dimples or wrinkles, which can typically be formed on the internal surfaces of the tubena.

On the other hand, the pigs themselves need to be maintained and removed from the tubena typically after use. To achieve this, a launch and reception set of a pig that connects to the tubena can be provided, and allows manual access to prepare, launch, replace or recover the pigs. Such launching and recovery operations can be inconvenient, time consuming and therefore expensive.

Another specific method of cleaning involves a gel that is pumped through a tubena. However, this technique is problematic because the gels are highly viscous, so that particles or dirt removed from the sides of a tubenail accumulate on an outer surface of the gel so that while the gel moves along, dirt accumulated sticks more against the inner surfaces of the tubena. So, after using a gel,

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a second cleaning operation is often required to eliminate waste caused by the use of the gel itself. In addition, the viscous nature of the gels can lead to obstructions, particularly when the material is pressed in front of the gel and in restrictions in the tuben system. Moreover, gels are expensive, and prohibitive, if required to clean long-distance tubenas.

Furthermore, the removal of accumulated material in a tube or tubena system, for example, the paraffin wax accumulated in an oil pipe, is known to be carried out by passing specific solvents through the pipe to dissolve the material. However, this technique suffers in that the solvent is often unevenly imparted to the surface of the tubena and it can be difficult to recover the solvent completely. In addition, high volumes of solvent are often needed, which can be expensive.

In addition, difficulties may be encountered in relation to fluid transport pumps where solid particles, such as sand, are suspended in the fluid and settle due to gravity, and may cause the pump to capture them and stop working particularly when The pump goes out. In this way, solid particles that settle can cause the pump to capture and stop working, and repair costs are typically high because pumps of this nature typically need to be disassembled into component parts and replaced, which It is a time-consuming process. In addition, it may be necessary to stop dependent industrial processes while the pump is out of operation.

WO00 / 29711 of PALMER describes a method for removing unwanted fluids from a well. More specifically, it describes a method for cleaning underground wells such as hydrocarbon wells by using platelets and / or specific translocation fibers.

Document DE10142917 of SCHOTT GLAS describes a suspension for polishing surfaces that includes polishing elements and an additional constituent in the form of fibers.

Document US5704991 of MARCUS describes a composition and a washing method. More specifically, it describes a process for cleaning vehicles, especially automobiles, with an alkaline washing composition, which preferably comprises one or more surfactants, where the washing composition is combined with an aqueous solution of a cellulose derivative that forms a semi-stable composition that freeze and absorb / adsorb dirt particles removed from the surface when the composition is rinsed.

DUFFY document US4605329 describes the hydraulic transportation of objects. More specifically, it describes a method and an apparatus for the hydraulic transportation of objects, by using a support material such as a quantity of flexible fibers mixed in a liquid.

Document DE19855255 of KAERCHER GMBH & CO ALFRED describes a detergent. More specifically, it describes a cleaning agent that facilitates the contactless removal of the gray coloration of surfaces to be cleaned, the cleaning agent contains cellulose in fibrous form.

WO9519326 of ALVAREZ describes a composition based on micronized sepiolite, and the preparation, process and application to the cleaning and restoration of buildings and monuments.

RYOBI document EP0767010 describes a system and method for cleaning a liquid passage by negative pressure.

Document US6419019 of PALMER describes a method for removing particulate material from a well by using platelets and / or translocation fibers. More specifically, it describes the use of specific fibers to aid in the transport of the partroule material.

DAVIS document EP0867495 describes a method for removing remains from a well. More specifically, it describes a method for cleaning debris from a well and includes the steps of injecting hydrophilic fibers selected from the group consisting of polyolefins, polyesters and nylon, suspended or dispersed in a petroleum-based liquid or water-based liquid in a well.

MEYER US3852200 describes a perforation liquid containing microcrystalline cellulose. More specifically, it describes a drilling liquid for use in abrasive blasting.

USIB29575 of WEIBEL describes the drilling of wells and production fluids that use cellulose from parenchymal cells. More specifically, it describes drilling fluids of circulating and non-circulating wells.

According to a first aspect of the invention, a cleaning fluid is provided for cleaning a fluid transport apparatus, as claimed in claim 15 and the dependent claims.

Such cleaning fluid may comprise abrasive particles and fiber particles mixed in the liquid.

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Therefore, the cleaning fluid can be applied to collect and transport additional particles in the volume of the liquid, such as contaminants, residues, sediments or other solids that may be present and / or deposited inside the tubenas, containers, tanks of sedimentation or other fluid transport apparatus. That way, the cleaning fluid can clear the extra particles.

The fiber particles and / or any of said additional particles collected by the fluid can be suspended in volume.

The fiber particles and / or any of said additional particles collected by the fluid can be suspended in volume.

The cleaning fluid may take the form of a suspension to be pumped through a tubena, canena, tank, container or other fluid transport apparatus to interact with the interior surfaces of said fluid transport apparatus.

The cleaning fluid may comprise:

0.5-10% w / w fiber particles; and 90-99.5% w / w of liquid.

Preferably, the liquid comprises water. The liquid may comprise a liquid saline solution, such as salt water. The liquid may comprise an oily base, to take the form of an oil-based liquid.

The cleaning fluid may include a treatment agent to treat a surface of the fluid transport apparatus. The treatment agent may comprise a lubricant or corrosion inhibitor. The treatment agent can be adapted to apply a protective coating to the surface.

The cleaning fluid may include a solvent to treat a surface of the fluid transport apparatus.

In one embodiment, the cleaning fluid can be adapted to erode an inner surface of a fluid transport apparatus. More specifically, the cleaning fluid may comprise abrasive particles. The abrasive particles can be adapted to abrasively remove said residues lining a tubena wall, for example, through a scraping action.

The abrasive particles can be dispersed and / or suspended in the volume of the liquid. In this embodiment, the fiber particles dispersed in the liquid volume can provide support to allow the abrasive particles to be suspended in the volume. Thus, during use, the cleaning fluid can scrape, stir, and remove solid waste by the presence of abrasive particles, while the fibers dispersed in the volume allow the particles that have been removed to be collected and transported along the volume. .

The cleaning fluid may comprise:

0.5-10% w / w fiber particles;

0.5-10% w / w abrasive particles; and 80-99% w / w of liquid.

The abrasive particles may comprise gravel, sand, clay, quartz, diamond, and / or tungsten carbide particles. The abrasive particles may comprise particles of different dimensions, shapes, and / or sizes to facilitate the cleaning of dimples or cavities formed in a wall of a fluid transport apparatus and which may be of different scales.

The cleaning fluid is further adapted to allow additional particles to mix in volume during use. For example, the cleaning fluid can be adapted to act as a low viscosity fluid to facilitate mixing of additional particles in the volume. Thus, since the additional particles, such as solid waste, are removed and / or collected, the additional particles are easily mixed in the volume so that the cleaning fluid acquires a new constitution that includes the additional particles. In this way, the contaminating particles can be effectively incorporated into the volume to be carried / transported with the cleaning fluid, for example, when pumped through a fluid transport apparatus.

In a specific embodiment, the cleaning fluid may take the form of a mixture of paper mache, wherein the volume of liquid comprises water and the fiber particles comprise particles of fibers derived from paper and / or newspaper, in admixture.

The fluid transport apparatus may include pumps, tanks, containers, tubes, tubenas or the like.

According to a second aspect of the invention, there is provided a method of using a cleaning fluid of

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according to the first aspect of the invention in the cleaning of a fluid transport apparatus, as claimed in claim 1 and the dependent claims.

The method may comprise the step of adding abrasive particles to the mixture.

The fluid transport apparatus may include a pump, a tank, a canena or the like.

The method may comprise the step of mixing constituents to form a low viscosity cleaning fluid. In this way, the additional particles, such as contaminants, of the fluid transport apparatus are effectively mixed and can be transported with the volume of the cleaning fluid.

The method may comprise the step of pumping the pressure cleaning fluid to force the cleaning fluid through the fluid transport apparatus to collect additional particles such as waste or solid deposits. The method may comprise the step of pumping the cleaning fluid in contact with interior surfaces of the fluid transport apparatus to scrape debris from the surfaces and / or collect and transport loose debris.

The cleaning fluid may be a cleaning fluid according to the first aspect of the invention.

In one embodiment, a treatment fluid is provided comprising a liquid and sufficient particles in admixture with it to treat a fluid transport apparatus, wherein the fiber particles are dispersed in a volume of the liquid in an amount not exceeding particle transport capacity of that volume of liquid.

The fluid may comprise a treatment agent for applying a protective coating to a surface of a fluid transport apparatus. The treatment agent may include a corrosion inhibitor.

The liquid and the particles in mixture can initiate a cleaning action within a fluid transport apparatus. The fluid transport apparatus may include a pump.

Other features of this additional aspect of the invention can be defined with reference to any one, or more, of the features and stages of the corresponding method according to the case of the first to the second aspect of the invention.

Modes of the invention will now be described by way of example only with reference to the following drawings, in which:

Figure 1 is a cross-sectional representation of a tubena with a cleaning fluid, which is pumped through it to remove loose solid particles from the tubena according to an embodiment of the invention. Figure 2 is a cross-sectional representation of a tubena with a cleaning fluid that is pumped through it to remove solid residues formed in the internal walls of the tubena according to an additional embodiment; Y

Figure 3 is a close-up representation of sand particles of different sizes of the cleaning fluid of Figure 2.

Referring first to Figure 1, a fluid transport pipeline 10 is generally shown. Figure 1 shows a cleaning fluid 12 introduced to the pipeline 10 during use, while a pressure is supplied through the pipeline 10 in the direction of arrow 11 to remove loose solid particles 18 and clean the pipe 10.

In this example, the cleaning fluid 12 comprises water 14 (constituting a "liquid") and newspaper particles 16 (constituting "fiber particles") in admixture.

Newspaper particles 16 are dispersed in water 14, and are generally presented in their entire volume. In this case, the cleaning fluid is prepared from 1% w / w of newspaper particles, and 99% w / w of water. Newspaper particles appear as "suspended" in the volume. The resulting distribution of the newspaper particles allows the loose solid particles 18 (which constitute "additional particles"), to rise in volume when the cleaning fluid moves through the tubena, to be suspended or transported along with the fluid Cleaning, in volume.

The cleaning fluid 12 acts as a thick liquid or "suspension" in the tubena 10. However, its total viscosity is low and sufficient, so that the loose particles 18 are collected, extracted and mixed in the volume of the fluid 12 as it moves along the tubena 10. Thus, the cleaning fluid 12 changes its composition and acquires additional constituent particles as it progresses through the tubena; the additional particles 18 themselves and the newspaper particles 16 are mixed in the water 14. The newspaper particles help to transport or suspend the loose particles of the tubena in the cleaning fluid.

In Figure 2, a tubena 100 is generally shown with a cleaning fluid that is pumped through in a manner similar to that described with reference to Figure 1. However, in this example, the cleaning fluid 112 is prepared in its initial constitution to comprise newspaper particles and additionally abrasive particles 122 in

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mixing in the volume of water 114. More specifically, the cleaning fluid 112 is formed from a first volume comprising 99% w / w of water 114 mixed with 1% w / w of newspaper particles 124 (identical to the cleaning fluid 12 described above), and a second volume of sand particles 122 (constituting the "abrasive particles") that is equal to the first volume.

The newspaper particles 116 help to transport or suspend the sand particles 122 of the tubena in the volume of water, and the cleaning fluid 112 as a whole acts as a suspension and functions during use in a manner similar to that described. in the example of Figure 1.

In addition, the cleaning fluid 112 in this example works during use to scrape the tartar covers 126 or unwanted or embedded debris onto an inner wall 120 of the tubena 100. As the cleaning fluid 112 is pumped under pressure through the tubena, the sand particles 122 scrape and erode the debris to remove them from the wall of the tubena.

The waste or inlay material that is removed from the tubena wall is also mixed in the volume of water and transported through the tubena in the volume along with the fluid. The loose solid particles acquired in the volume, together with the sand particles, and newspaper particles are present again in the mixture in the volume of water.

With reference in addition to Figure 3, the sand particles 122 are shown in more detail. The particles have different sizes so that the composition can effectively clean the cavities and dimples 130 formed in internal walls of the tubena 120. This Figure demonstrates that larger sand particles 128 are not suitable for cleaning although they have a strong action abrasive However, smaller abrasive particles 129 can access smaller cavities and dimples 130 to clean them more effectively.

The cleaning fluid as described in the present examples is prepared manually by measuring adequate amounts of the fiber particles, water and abrasive particles if necessary, these constituents are located together in a receptacle, and mixed by manual agitation. Of course, it will be appreciated that a mechanical arrangement could be used to automate these tasks and prepare sufficient amounts of the cleaning fluid. The ingredients do not need to be added in any particular order.

In other embodiments, it should be understood that instead of water, an oil-based liquid is used. In addition, it should be understood that other types of fibers or abrasive particles may be used instead of those described in the specific examples. In particular, it should be understood that although the examples describe the use of the cleaning fluid in relation to the tubenas, it could also be applied to clean another fluid transport apparatus, such as tanks, pumps, containers, or other apparatus.

In another example, the mixture of liquid and fiber particle of Figure 1 includes a corrosion inhibitor in the liquid. The corrosion inhibitor has a "sticky" constituent that allows it to separate from the fluid and naturally adhere to a surface of the tubena when it comes into contact with the surface of the tubena. Thus, as the fluid is pushed along the pipeline at a certain pressure so that the fluid makes contact with the sides, a coating of a protective corrosion inhibitor is applied uniformly over the surface.

It will be appreciated that the corrosion inhibitor could typically be introduced into the fluid towards the end of a cleaning process, particularly after the abrasives used to remove unwanted residues have been introduced and applied to the fluid. Thus, it will be more generally appreciated that the constituents of the fluids described in the present description can be introduced at different times as long as they are needed to achieve particular cleaning or treatment effects.

In another illustrative variant that is not of the invention as currently claimed, a mixture of liquid and fiber particles constituting fluid 12, as indicated above with reference to Figure 1, is used as a means of transport for transporting aggregates. of road from one place to another. In this example, a storage tank containing aggregate materials is provided at a roadside location, and the mixture is supplied to the tank and mixed with the aggregated materials so that the materials are transported in the volume of the liquid. Then, the fluid that includes the aggregate is pumped to move the aggregates typically more easily than previously possible, from the tank to the road where the aggregate material can be equalized to form a roadbed.

The present invention provides a number of advantages. The cleaning fluid that has fiber particles and mixed water provides a suspension-type mixture capable of collecting and transporting loose solids along the pipeline to remove them and clean the pipeline. In addition, providing the cleaning fluid with abrasive particles that are transported in a volume of fluid and dispersed in the volume, allows scraping the accumulated scale on the inner surfaces of the tubena, and also dragging on the volume to remove them from the tubena.

In addition, unwanted particles and residues mix easily in and disperse in the volume of the fluid due to its low viscosity (facilitated by the use of water), so the cleaning fluid is an effective means of transport for

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Particulate and efficient to separate dirt from the lateral surfaces of the tubena, and outside the front part of the flow. In turn, this helps to clean the tubena in a single pumping process, potentially by using a single batch of cleaning fluid, and avoid clogging. In addition, cleaning fluid components are readily available and therefore the technique is cost effective, so that tubenas can be cleaned over long distances.

In the examples where the fluid transport apparatus includes a pump, the cleaning fluid described above is particularly effective for transporting solid particles so that sedimentation in the pump is avoided, and thus preventing the pump from getting stuck.

In other examples, the cleaning fluid includes a solvent that helps remove solids from the surface of the tubena. The solids that are removed are suspended in the fluid due to the presence of the fiber particles, and in this way the fluid forms a "solvent" suspension. This suspension is advantageous because it guarantees a relatively uniform application of the solvent on the surface of the tubena, decreases the amount and volume of use of the expensive solvent, facilitates the recovery of the solvent in comparison with the traditional solvent techniques in the prior art.

In addition, the ability of the cleaning fluid to withstand abrasive particles of various different sizes, together with its general fluidity as described above, allows access to cavities, wrinkles, corners, dimples and areas around other irregularities in the transport apparatus of fluid, to clean it, and treat it effectively.

Various improvements and modifications can be made within the scope of the invention described in the present description. In particular, it will be appreciated that in other embodiments the water particle to fiber ratios (for example, newspaper particle) indicated may differ from the specific illustrative relationship referred to in the present description. For example, the cleaning fluid may contain 5% w / w of newspaper particles and 95% of water. In other cases, the cleaning fluid may contain 50% w / w of newspaper particles. The fiber and water composition used for a particular application will typically be dependent on the weight, size and suspension capacity of the selected fibers, and the required fluid viscosity.

Claims (18)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 Claims 1. Use of a cleaning fluid (12, 112) to clean a fluid transport apparatus (10) in which a fluid can flow out or through it, the cleaning fluid (12, 112) comprises: a volume of liquid (14, 114) and fiber particles (16, 124) comprising paper fibers, or fiber particles derived from newspaper and / or paper, the cleaning fluid (12, 112) has low viscosity and comprises particles of fibers distributed in the volume of liquid (14, 114) in an amount that does not exceed the transport capacity of the particles of that volume of liquid and has sufficient particles of fiber (16, 124) distributed in the volume to provide a cleaning action during use, the cleaning action comprises additional particles (18, 118) collected and transported together with the cleaning fluid in the volume when the cleaning fluid (12, 112) flows through the fluid transport apparatus (10). 2. Use of a cleaning fluid (12, 112) as claimed in claim 1 wherein the cleaning fluid (12) is in the form of a suspension for pumping through the fluid transport apparatus (10) to interact with the inner surfaces of said fluid transport apparatus. 3. Use of a cleaning fluid (12, 112) as claimed in claim 1 or 2 wherein the cleaning fluid (12) changes its composition, acquiring the additional particles (18, 118) as additional custom constituent particles flowing through the fluid transport apparatus (10). 4. Use of a cleaning fluid (12, 112) as claimed in any of the preceding claims wherein the cleaning fluid comprises: 0.5-10% w / w in fiber particles (16, 124); and 90-99.5% w / w of liquid (14, 114) optionally, the cleaning fluid (12, 112) comprises: 5% w / w fiber particles 16, 124; and 95% w / w of liquid (14, 114), optionally, the cleaning fluid (12, 112) comprises: 1% w / w fiber particles (16, 124); and 99% w / w of liquid (14, 114). 5. Use of a cleaning fluid (12, 112) as claimed in any preceding claim in which the liquid comprises water or salt water or the liquid (14, 114) comprises an oil-based liquid. 6. Use of a cleaning fluid (12, 112) as claimed in any one of the preceding claims wherein the liquid (14, 114) comprises water or salt water, and the cleaning fluid is in the form of a mixture of paper mache. 7. Use of a cleaning fluid (12, 112) as claimed in any of the preceding claims wherein the cleaning fluid (12, 112) includes a treatment agent for treating a surface of the fluid transport apparatus, or The cleaning fluid (12, 112) includes a treatment agent for applying a protective coating to the fluid transport apparatus. 8. Use of a cleaning fluid as claimed in claim 7 wherein the treatment agent comprises a lubricant or corrosion inhibitor, and / or wherein the treatment agent comprises a solvent to treat the interior surfaces of the transport apparatus of fluid 9. Use of a cleaning fluid (112) as claimed in any preceding claim wherein the cleaning fluid (112) comprises abrasive particles (122) and fiber particles (124) in admixture in the liquid (114), and wherein the abrasive particles (122) are dispersed and / or suspended in the volume of the liquid (114) with the fiber particles (124) dispersed in the volume of the liquid (114) that provides support to allow the abrasive particles to be suspended in the volume. 10. Use of a cleaning fluid as claimed in claim 9 wherein the cleaning fluid comprises: 0.5-10% w / w fiber particles (124); 0.5-10% w / w abrasive particles (122); and 80-99% w / w of liquid. 11. Use of a cleaning fluid (112) as claimed in claim 9 to 10 wherein the abrasive particles (122, 128, 129) comprise gravel, sand, clay, quartz, diamond, and / or carbide particles of tungsten and / or wherein the abrasive particles (122, 128, 129) comprise particles of different dimensions, shapes, and / or sizes to facilitate the cleaning of dimples or cavities (130) formed in a wall of a fluid transport apparatus (10) and can be of different scales. 5 10 fifteen twenty 25 12. Use of a cleaning fluid (12, 112) as claimed in any preceding claim comprising the step of pumping the pressure cleaning fluid to force the cleaning fluid through the fluid transport apparatus (10). 13. Use of a cleaning fluid (12, 112) as claimed in any preceding claim comprising: - introducing a cleaning fluid comprising the first constituents at first, - introduce other constituent (s) to the cleaning fluid at different times (s). 14. Use of a cleaning fluid (12, 112) as claimed in claim 13, wherein the cleaning fluid comprises abrasive particles as a first constituent, and wherein a corrosion inhibitor is introduced as an additional constituent at the end of the cleaning process. 15. A cleaning fluid (12, 112) for flowing through a fluid transport apparatus (10) in use of any of claims 1 to 16 comprising: - a volume of liquid (14, 114); Y - fiber particles (16, 124) comprising paper fibers, or fiber particles derived from newspaper and / or paper, - the cleaning fluid (12, 112) has low viscosity and comprises distributed fiber particles (16, 124)
in the volume of liquid (14, 114) in an amount that does not exceed the transport capacity of
particles of that volume of liquid and have enough fiber particles distributed in the volume of liquid to provide a cleaning action during use; the cleaning action comprises additional particles (18, 118) that are collected and transported together with the
cleaning fluid in the volume while the cleaning fluid flows through a transport device fluid. 16. Cleaning fluid according to claim 15 comprising any of the fluid characteristics of claims 2 to 14.