GB2573615A

GB2573615A - Fluid collector

Info

Publication number: GB2573615A
Application number: GB1903026.1A
Authority: GB
Inventors: Ibbotson Colin
Original assignee: Manvers Engineering Ltd
Current assignee: Manvers Engineering Ltd
Priority date: 2018-03-06
Filing date: 2019-03-06
Publication date: 2019-11-13
Anticipated expiration: 2039-03-06
Also published as: GB201903026D0; GB2573615B; GB201803602D0

Abstract

A fluid collection surface 3 with upstanding walls 2, 2’ is configured to support 4 a vehicle, equipment or machinery. The surface is provided with a sump 3 or well into which liquids that are spilt, leaked or dripped during refuelling, washing or maintenance of the vehicle can be collected and retained for appropriate disposal. The surface may be sloped toward the collection well, the well preferably having an opening (14, Fig.6) to allow the drainage of water. The collector may have a primary (15, Fig.6) and secondary (16, Fig.6) absorbent material such as a sponge, foam, nonwoven material for the absorption of liquids. Preferably, the nonwoven material is a polypropylene based felt.

Description

FLUID COLLECTOR

FIELD OF INVENTION [0001] The present invention relates to a receptacle that collects fluids such as fuels, oils, hydrocarbons that may be spilt when being introduced to or washed from vehicles, equipment or machinery.

BACKGROUND ART [0002] Vehicles, equipment and machinery require many types of fluids to operate or for their cleaning and maintenance. This fluids may be introduced into the vehicles or may be applied to their surfaces temporarily or semipermanently. In every type of application there is always the risk of inadvertent fluid spillage either minor through dripping when coupling or decoupling filing equipment or major through a leak or failure of a seal or container.

[0003] Such leaks and spillages may be aesthetically unsightly and are often hazardous. These hazards may take the form of fire or explosion risks or result in operators or vehicles being exposed to personal hazards or operation risks suchas contamination, slip hazards and loss of vehicle control. In addition such leakages and spillages may pose a threat to the environment and contaminate waterways and natural habitats and endanger wildlife and vegetation.

[0004] A further problem with such leakages and spillages is that they may occur in the presence of water either through a cleaning process where the aqueous cleaning fluids are contaminated with the fuel or hydrocarbon or more usually when any leakage and spillage is exposed to rainfall or other forms of precipitation and this then provides a mixture of fuel or hydrocarbon in water. One particular problem area is fuel filling stations that may be stationary or semi-permanent and which are used to fuel and re-fuel a large number of vehicles with regular coupling and decoupling activities. In these arrangements there is a high risk of leakage and spillage and they are often exposed to ambient precipitation which compounds the leakage and spillage related problem.

[0005] A further problem with this area is that even if a spillage or leakage is accommodated many solutions then have the additional challenge of disposal or the retained material after leakage or spillage either in its relatively pure form or in combination with a collection device or material.

[0006] Various devices and methods have been devised to alleviate the problem of liquid leakage or spillage. These have typically taken the form of drip mats or drip trays or a combination thereof.

[0007] Whilst in many cases these devices and solutions have a positive effective in limiting the impact of leakage and spillage there is still a need for useful solutions to the problem of leakage and spillage of fuels and hydrocarbons especially when combined with aqueous contamination.

DISCLOSURE OF THE INVENTION [0008] The fluid collector of the present invention provides a means for trapping and collecting accumulated occasional minor spillages or leaks and also to prevent wider loss of fluid under catastrophic leakage conditions due to for example liquid filing failures.

[0009] The fluid collector at its core provides a fluid collection surface preferably a tray form arrangement that comprises an impermeable collection surface floor with upstanding walls at two opposing edges of the floor and a sump arrangement located at one or more of the transverse opposing edges. If there is only one sump arrangement then the second opposing transverse edge may also have an upstanding wall. It is preferred that both of the opposing transverse edges are associated with a sump arrangement. By definition the sump arrangements will have the majority of their volume located below the plane of the tray surface so that during use any liquid that enters the tray will ordinarily flow off of the surface of the tray floor and into the sump arrangement. The upstanding walls will prevent liquid from escaping from the tray and ensure it is directed to and deposited into the sump arrangements. The upstanding walls may continue into the sump arrangements to provide the upper wall surfaces of the sump arrangements. In one embodiment the tray may be replaced by a collection surface that comprises a single sump arrangement located at its periphery. In such an arrangement any liquid that falls upon the collection surface flows off that surface and into the sump at the collection surfaces periphery.

[0010] In a preferred embodiment the fluid collector further comprises vehicle or equipment support means located above the fluid collection surface. Preferably this support means is porous. Ina further preferred embodiment the fluid collector is arranged and is of dimensions that a transportation vehicle may be driven not and supported by the fluid collector Preferably this support means takes the form of transverse beams secured permanently, semi-permanently or temporarily to the side wall of a tray form arrangement. The support surface may be in the form of a grill. It is preferred that the effective bottom surface of the support surface defines a primary separation region with the collection surface, which is therefore located between the effective bottom surface of the support surface and the contact surface, and into which may be placed absorbent and/or adsorbent materials (hereinafter referred to collectively as absorbent/adsorbent materials). This primary separation region is open at points on its periphery to allow the introduction of absorbent/adsorbent materials into the primary separation region. Such absorbent/adsorbent materials are preferably located across the whole width and length of the support means and preferably are located above and cover the whole of the collection surface located below. This will ensure that any leakage of spillage from a vehicle or machinery resting upon the support means will pass through the support means into the primary separation region and will either be absorbed/adsorbed by the adsorbent/adsorbent material or must pass through it to make contact with the collection surface. This primary separation region accommodates what may be therefore be termed as the primary separation materials. Preferably the primary separation material is in the form of a web of material that may be introduced into the fluid collector and into the primary separation region via one or more openings of the separation region located at the edges of the collection surface. Preferably these openings are located at the sump edges of the collection surface or alternatively they and the collection surface edge extend over the sump arrangement. Preferably the web of primary separation material is pulled into and through the primary separation region by means of a wire and pully arrangement and it may equally be removed after use through the same arrangement.

[0011] In one embodiment the vehicle or equipment support means has a fixed or semi-permanent region and at least one region that is removable or may be opened to expose in part the primary separation region. These removable or openable regions may preferably be located at one or more of the sumps. When close or in place they may cover the sump region and a part of the primary separation region and being removable or capable of being opened provide access through the support surface to the primary separation region and the sump or sumps. These support means may therefore comprise a pivoted section that may be opened about its pivot point to expose the sumps and primary separation region for access to both.

[0012] In a preferred embodiment the top of the collection surface is not planar but has a surface that is arranged so that any liquid which falls upon its surface will travel under the influence of gravity towards and be collected in the sump or sumps of the collector. Ideally the collection surface is simply sloped so that liquid impinging upon its surface flows towards its edge and into the sump or sumps. In a preferred embodiment the collection surface is in the form of two sloping surfaces joined at an apex and providing gravity induced liquid flow to sumps located at or under the bottom edge of each slope.

[0013] The sumps may simply act as a liquid collection sump or preferably they act as a secondary separation region and preferably may contain secondary absorbent/adsorbent. In a preferred embodiment this secondary absorbent/adsorbent is selected to provide both a general fluid absorption and or adsorption function to capture and remove low levels of fuel or oil and a deluge function where it effectively forms a plug or barrier to large quantities of fuel or oil escaping from the fluid collector. It is preferred that any water that may into the sump arrangements is able to exit these sump arrangements substantially free of any hydrocarbon or other organic or chemical contamination.

[0014] In one embodiment the sumps may be impermeable and any liquid that flows or falls into them will be contained until removed. In a further embodiment the sumps are arranged to have openings that allow some liquid to pass out of the sump and in particular to allow decontaminated water to pass out of the sumps. In this arrangement the sump will comprise secondary absorbent/adsorbent with dual function; during operation of the collector water with oil or fuel contamination will initially pass through the primary absorbent/adsorbent material and only trace levels of contamination will remain in the aqueous material that passes through the primary absorbent/adsorbent. This low level contaminated aqueous liquid will then pass into the sumps and through the secondary absorbent/adsorbent material where the traces of fuel or oil are removed before the aqueous stream leaves the sump and to conventional drainage. The secondary absorbent/adsorbent may take the form of a sponge or foam or nonwoven material that is formed and shaped to fit tightly within the sumps to ensure that all of the liquid entering the sumps will pass therethrough. It is also possible that the secondary absorbent/adsorbent material is in the form of a powder or particles that fill the sump but this is not preferred as it adds further complications for maintenance and replacement of the secondary absorbent/adsorbent materials.

[0015] In one embodiment the collector further comprises one or more and preferably two ramp sections that may be integral with the main body of the collector or which may be placed adjacent and secured to the main body of the collector when in position for use. Preferably the ramp sections are integral with the main body of the collector. The function of these ramp sections is to enable vehicles to access the vehicle support means located above the fluid collection surface. Any suitably arranged ramp is sufficient and preferably the ramp will comprise perforated material so that any liquid precipitation does not accumulate on its surface. In addition the ramps may have roughened surfaces to assist traction. When the collector of the present invention is not for use with mobile vehicles then the ramps may be dispensed with.

[0016] The fluid collector of the present invention may be manufactured from any suitable material that is robust enough for the function of the collector. Typically the collector may be manufactured from metal such as mild steel or aluminium or it may be manufactured from engineering polymers or composites. In a preferred embodiment the collector is designed to be easily installed and to be easily removed and relocated. To this end it is preferred that the collector comprises lift guides for accommodating the use of a fork lift truck to install or move the collector. In a preferred embodiment these lift guides are located towards the bottom of the main body of the collector and are transverse to the longest axis of the collector.

[0017] In general use the fluid collector of the present invention may be operated as follows. The fluid collector may be placed adjacent to a stored source of fuel or oil or other liquid for transfer. Any vehicle requiring to be refiled with a particular fluid is driven onto the vehicle support surface typically via the ramps. The vehicle is then coupled using any appropriate coupling or filing arrangement to enable fluid transfer from the storage facility to the vehicle. The required amount of liquid is transferred from the storage facility to the vehicle and then the coupling or filler is decoupled from the vehicle. It is typically at this point that residual liquid on the coupling or filing hose escapes and is normally spilt. With the present invention this liquid passes through the porous vehicle support surface and impinges upon the primary absorbent/adsorbent material located within the primary separation region of the collector and is absorbed/and or adsorbed into the material. The vehicle is removed from the collector to and the collector is then dormant until the next liquid transfer operation. During this dormant period the collector may be exposed to precipitation such as rainfall. This precipitation will fall upon the collector and pass through the vehicle support surface and impact the primary absorbent/adsorbent material, which may have absorbed/adsorbed fuel, oil or similar. The precipitation may then be able to pass through the primary absorbent/adsorbent and will contact the fluid collection surface and because it is sloped towards the sumps of the collector will cause the precipitation to flow towards and into the relevant sump. On entering the sump this liquid may simply be retained in the sump, potentially with low levels of fuel or oil contamination until it is removed during servicing of the collector. Alternatively the contaminated water may pass through a secondary absorbent/adsorbent so that low levels of fuel and oil are removed; the servicing requiring the simple removal of the secondary absorbent/adsorbent with absorbed fuel or oil. Alternatively the water that enters the sump may after passing through the secondary absorbent/adsorbent pass through drainage points within the sump and out of the collector. In one embodiment and under normal operational conditions the secondary and primary absorbent/adsorbent materials retain low levels of contamination and allow precipitation to pass through. In further embodiments the primary absorbent/adsorbent material may be highly oleophilic and any water that impinges upon its surface flows off that surface and into the sump arrangements. In a further embodiment the secondary absorbent/adsorbent material may be hydrophilic enough and porous enough such that water with low levels of hydrocarbon may be able to pass through the secondary absorbent/adsorbent material ensuring high levels of contact with the surfaces of the secondary absorbent/adsorbent material, which is oleophilic enough to remove traces of hydrocarbon and or organic materials in the water. If there is a major spillage or discharge of fuel or oil then their secondary function of completely preventing further flow to or from the sump may be activated and major leakage may be prevented.

[0018] The primary absorbent/adsorbent material is preferably in the form of a web comprising materials that absorb and or adsorb the components of fuel or oil and/or react with fuel and oil components. This may be a web of layered materials one of which comprises the material for absorbing/adsorbing fuel or oil and/or reacting with fuel and oil.

[0019] The adjacent layers may comprise woven and/or non-woven materials and preferably comprise non-woven materials. Preferably these layers are non-woven fibrous layers that are oleophilic and are hydrophobic and porous enough so that water with or without hydrocarbon contamination may pass therethrough. In one embodiment the bottom layer may be mechanically bonded to or replaced by a hydrophilic layer and this layer may be a non-woven material. In this embodiment any water and hydrocarbon/oil mixture will first pass through the top layer and a proportion of the oil/hydrocarbon may be retained in the layer and separated from the water. The oil/hydrocarbon contaminated water remaining may then pass through to the middle reactive/ absorbent/adsorbent layer and remaining oil/hydrocarbon is removed from this mixture. Purified water is then able to pass from this layer with ease into and through the bottom layers and especially the hydrophilic layer, which whilst allowing water to pass therethrough repels the oil/hydrocarbon and forces this back into the oil reactive/absorbing layer. This stack of mechanically bonded multiple layers is able to therefore act as a graduated filter for the removal of oil/hydrocarbon from water. In an alternative embodiment the top layer may be mechanically bonded to or replaced by a hydrophilic layer and this layer may be a non-woven material.

[0020] The porous adjacent non-woven layer materials may be broadly defined as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically. They are flat or tufted porous sheets that are made directly from separate fibers, molten plastic or plastic film. They are not made by weaving or knitting and do not require converting the fibers to yam.

[0021] These nonwovens are typically manufactured by putting small fibers together in the form of a sheet or web and then binding them either mechanically (as in the case of felt, by interlocking them with serrated needles such that the inter-fiber friction results in a stronger fabric), via adhesive, or thermally often with use of a binder material. Examples of suitable non-woven materials include staple nonwovens, melt-blown nonwovens, spun laid nonwovens, flash spun, spun jet, air-laid, wet-laid and other well-known forms. In many of these forms the laid fibre requires further treatment in the form of bonding of fibres to provide physical integrity to the nonwoven layer. Several bonding methods may be used and include be used: thermal bonding, hydro-entanglement, ultrasonic pattern bonding, needle punching/needle felting, chemical bonding with binders and meltblown, where fiber is bonded as air attenuated fibers intertangle with themselves during simultaneous fiber and web formation.

[0022] All nonwoven materials made by these techniques and which may be further processed to form a mechanical bond with an adjacent layer sandwiching a hydrocarbon absorbing and/or reactive material may be used in the present invention.

[0023] One suitable nonwoven is a polypropylene based felt material typically used in the manufacture of oil/hydrocarbon absorbing pads or matts and preferably is 4 denier polypropylene fiber in a nonwoven layer. Another suitable non-woven material is Geotextile-NW12, which is a polypropylene, staple fiber, needle-punched, nonwoven geotextile made with a proprietary additive. The fibers are needled to form a stable network that retains dimensional stability relative to each other. One preferred nonwoven material for one or more of the layers is a spun bond felt.

[0024] The hydrocarbon absorbing and/or reactive material layer may be a contiguous sheet of material as in a woven layer of material or may be a noncontiguous layer of material in the farm of fibres and/or particulate materials. It is preferred that this layer comprises non-contiguous particulate and/or fibrous material and most preferably non-contiguous particulate material. This material being retained and secured between two layers of non-woven material that are mechanically interlocked with each other preferably through needle punching. The position of the particulate material is effectively fixed after needle punching and interlocking of the two adjacent non-woven layers and through this arrangement the particles and groups of particles are in fixed isolation from each other. Hydrocarbons/oil and water may pass through the non-woven layer and when the hydrocarbon/oil makes contact with the hydrocarbon absorbing and/or reactive material it is removed and isolated whilst ensuring that the reacted material remains in fixed isolation within the layer. This arrangement maintains the flow of liquid through the layer and ensures maximum effective utilization of the absorbing/reactive material.

[0025] If desired the composite material of the present invention may comprise multiple layers hydrocarbon absorbing and/or reactive material separated by non-woven layers that are mechanically bonded to each other. In addition, the hydrocarbon absorbing and/or reactive material of the present invention may be incorporated into other layered structures where the additional layers have other functions or properties e.g. wear resistance. The composite material of the present invention may be in the form of a replaceable web or a fixed web.

[0026] This composite material in the correct form may be used as the secondary absorbent/adsorbent of the present invention for insertion into the sumps. This may be in the form of a stack of separable layers of absorbent/adsorbent material layers. During servicing and depending on the level of contamination captured in the sumps only the highly contaminated top layers of the stack may need to be replaced.

[0027] With reference to the primary and secondary absorbent/adsorbents for use in the present invention any fuel or oil absorbing and/or adsorbing fuel material may be used. In embodiments of the present invention the primary and secondary absorbent/adsorbents for use in the present invention are hydrocarbon swellable and/or hydrocarbon reactive polymeric material which imbibes and/or reacts with hydrocarbon organic liquids may be used. The polymer should imbibe and/or react with hydrocarbons under deluge conditions in order to form a hydrocarbon impenetrable plug of material by any suitable mechanism.

[0028] Preferably the oleophilic material for use in the sumps comprises a porous foam material and most preferably a reticulated foam material of the correct size and form. It may also comprise a layered stack of suitable materials.

[0029] The hydrocarbon absorbing/adsorbing and/or reactive materials may comprise any material or combination of materials that either absorb and or adsorb and/or react with hydrocarbons/oil to immobilize the hydrocarbon/fuel/oil and when present as a contaminant to remove the hydrocarbon/fuel/oil from a solvent or liquid such as water. Reaction is used in the broadest sense and includes materials that may dissolve in hydrocarbons/fuel/oils and in doing so cause the hydrocarbon/oil to solidify and become immobilized. Materials the separate the hydrocarbon/fuel/oil through absorption and/or adsorption are typically organic polymers or may be natural polymeric materials in the form of a sponge and/or woven material. These will typically be selected for the desired balance of hydrophilic and oleophilic properties for the level of hydrocarbon/fuels/oils that need to be absorbed/adsorbed. They may be in the form of mixtures of materials as foams and nonwoven materials for example as a composite to secure the desired balance of hydrophilic and oleophilic properties given any level of spillage and or contamination of aqueous streams. Suitable reactive materials are described below.

[0030] One suitable material is the commercially available material Green Rhino CG1 Polymer, supplied by Capture Green Limited, The Old Stables, The Gattinetts, East Bergholt, CO7 6QT, United Kingdom. This material is a blend of polymers that is specifically blended to capture and retain hydrocarbons such as oil, diesel, petrol, hydraulic fluid, transformer liquid and more. The polymers are capable of completely solidifying the hydrocarbon until it becomes a solid mass that will not teak - this offers an effective method for managing and removing unwanted waste oils from the environment. The polymers in the form of a white granular powder work by having a physical attraction with hydrocarbons. On contact with the hydrocarbon the viscosity increases creating a solid rubber like substance that will not leak, even under applied pressure. Once the polymers are activated by contact with hydrocarbon, the oil is locked in permanently and cannot be released.

[0031] A further suitable material is the commercially available material called C.I.Agent polymer as manufactured and sold by C.l. Agent Solutions® of 11760 Commonwealth Drive, Louisville, KY 40299, United States of America, [0032] A further suitable material is the commercially available material called Petroguard-D as supplied by Guardian Environmental Technologies, Connecticut, USA. This material takes the form of a dry white granular high capacity instant solidifying absorbent. This reacts with hydrocarbons/oil to form a solid. This material is typically provided commercially as granular particles of 20 to 60 mesh (approximately 0.84 to 0.25 mm). It is preferred that in all embodiments and aspects of the present invention that this material and other materials for this feature of the invention are ground so as to have a particle size that is less than 0.25 mm, preferably less than 0.20 mm and most preferably less than 1.5 mm. This reduced particle size provides better performance within the composites of the present invention.

[0033] A further suitable material is the commercially available material is called Deurex PURE as supplied by DEUREX AG, Dr.-Bergius-StraBe 8-12 06729 Elsteraue, Germany. This material is described as a hydrophobic wax cotton which has a high surface area and strongly adsorbs hydrocarbons/oils. It is a fibrous material.

[0034] Generally, there are at least three different types of oil-solidifying substances, including polymer sorbents, cross-linking agents, and polymers with cross-linking agents. Polymer sorbents, sometimes called super-sorbents, adsorb oil into spaces between polymers, and oil is held in these spaces by van der Waals forces, which are weak attraction forces between molecules. Examples of polymers that are capable of being solidifiers include, block copolymers such as styrene butadiene and related polymers, poly-tertiary-butylstyrene, polyacrylo-nitrile butadiene, polyisoprene (rubber), polyethylene and polypropylene, poly isobutylene and related polymers.

[0035] Cross-linking agents are chemical products that form chemical bonds between two hydrocarbons to solidify the oil. The reaction is that of a chemical one and typically can release a small amount of heat or absorb that amount of heat depending on the chemical used. Examples of cross-linking agents include norbornene, anhydrides, and a series of oil treating agents created by Pelletier and Siron (1999) (Environmental Technology and Chemistry, May 1999, Vol. 18, Issue 5, Pages 811-1075), that are prepared by reacting surfactants, alcohols or carboxylic acids with alkychlorosilanes in light hydrocarbon solvents.

[0036] Polymers with cross-linking agents also form chemical bonds. These types of solidifiers combine a polymeric sorbent with a cross-linking agent, and the purpose of this combination is to gain the advantages of both polymers and cross-linking agents. An example of this type of solidifier includes a product called RigidOil by British Petroleum. The agent consists of two liquids which are generally mixed shortly before applying to the oil. The one liquid consists of a 10% maleinized polybutadiene of molecular weight 8000 with 50% of odorless kerosene plus ester, as a diluent. The other liquid consists of a cross-linking agent, zinversate diethanolamine also in 50% kerosene/ester (9:1).

[0037] A general description of polymer-based oil-solidifying substances may be found in the Environmental Protection Agency's (EPA's) National Response Team (NRT) and Regional Response Team (RRT) factsheet entitled “Application of Sorbents and Solidifiers for Oil Spills” (February 2007), and a description of the three above-mentioned oil-solidifying substances may be found in Fingas, “A Review of Literature Related to Oil Spill Solidifiers 199013

2008” (September 2008), the teachings of both of which are incorporated herein by reference in their entirety.

[0038] In a further embodiment, the specific hydrocarbon/oil reactive polymers useful in the practice of the present invention are any polymers which are water insoluble and which swell and/or solidify on contact with organic liquids. Useful polymers may also swell on contact with water. However, additional swelling must occur when contacted with an organic liquid. Selection of a polymer for use with any organic liquid is readily accomplished by determining a swelling index for the polymer particles. Beneficially, such a swelling index is readily determined by immersing a particulate polymer to be evaluated in water until the polymer has reached equilibrium swelling and subsequently adding the desired organic liquid and determining the volume per unit weight of polymer after a period of 30 minutes with water and organic liquid and the volume per unit weight of the polymer when in equilibrium with water. The ratio of the volume per unit weight with organic liquid and water to volume per unit weight of the polymer with water provides the swelling index. If the polymer is soluble the swelling index is infinite. If the swelling index is greater than about 1.2 the polymer particles are useful in the practice of the present invention. Beneficially for most applications a swelling index of at least 1.5 and preferably greater than about 3 is desirable. It is not critical to the practice of the present invention to employ a cross-linked polymer which swells but does not dissolve. If the polymer swells in the presence of the organic liquid with or without water it is suitable for the practice of the present invention. However, it is desirable to employ a polymer which is cross-linked to a sufficient degree that it exhibits a swelling index between about 1.5 and 50 and preferably between about 3 and 50. By utilizing the cross-linked polymer the hazard of dissolution of the polymer over extended periods of time is eliminated.

[0039] Thus, in the present invention a wide variety of polymeric materials are employed with benefit in the swellable layer. Such polymers include polymers of styrenes and substituted styrenes; copolymers of vinyl chloride such as a copolymer of 60 weight percent vinyl chloride and 40 weight percent vinyl acetate; vinylidene chloride copolymers such as a copolymer of 75 percent vinylidene chloride and 25 percent acrylonitrile; acryllic polymers such as polymers of methylmethacrylate, ethyl acrylate and the like. In general, the chemical composition of the polymers is not critical. The polymers preferably show significant swelling; that is, at least a 25 percent increase in volume in a period of at least 10 minutes in the organic liquid to which the polymers are required to respond under desired service conditions of temperature and pressure. Particularly advantageous materials which respond to a wide variety of organic liquids are polymers of styrene such as polystyrene and polymers of styrene and divinylbenzene containing up to about 10 weight percent divinylbenzene. For general use with aliphatic and aromatic hydrocarbons, alkylstyrene polymers are of particular benefit. Such alkylstyrene polymers swell very rapidly on contact with aliphatic and/or aromatic hydrocarbons. Generally, the more rapid the swelling of the polymer the more rapid the shutoff when the organic hydrocarbon liquid is contacted. Alkylstyrene polymers usually show substantial swelling when in contact with organic hydrocarbon liquids in less than 1 minute.

[0040] Preferably, cross-linked polymers of styrenes, and advantageously of tertiary-alkylstyrenes, are utilized as the imbibing agent in the middle layer of the containment pad of this invention. Those alkylstyrenes which can be used to prepare these polymers have alkyl groups containing from four to 20, and preferably from four to 12, carbon atoms, such as: tertiary-alkylstyrenes including for example, p-tert-butylstyrene, p-tert-amylstyrene, p-tert-hexylstyrene, p-tert-octylstyrene, p-tert-dodecylstyrene, p-tert-octadecylstyrene, and p-tert-eiscosylstyrene; n-alkylstyrenes including for example n-butylstyrene, namylstyrene, n-hexylstyrene, n-octylstyrene, n-dodecyl-styrene, noctadecylstyrene, and n-eicosylstyrene; sec-alkystyrenes including for example sec-butylstyrene, sec-hexylstyrene sec-octylstyrene, sec-dodecylstyrene, secoctadecylstyrene, and sec-eicosylstyrene; isoalkyl-styrenes including for example isobutylstyrene, iso-amylstyrene, isohexylstyrene, isooctylstyrene, isododecyl-styrene, isooctadecylstyrene, and isoeicosylstyrene; and copolymers thereof.

[0041] Especially preferred for use in the practice of this embodiment of the invention are cross-linked copolymers of such alkylstyrenes as heretofore described and an alkyl ester derived from C1 to C18 alcohol and acrylic or methacrylic acid or mixture thereof.

[0042] Suitable monomers which may be employed as comonomers with the alkylstyrene include such materials as vinylnaphthalene, styrene, .alpha.methylstyrene, ring-substituted .alpha.-methylstyrenes, halostyrenes, arylstyrenes and alkarylstyrenes; methacrylic esters, acrylic esters, fumarate esters and half esters, maleate esters and half esters, itaconate esters and half esters, vinyl biphenyls, vinyl esters of aliphatic carboxylic acid esters, alkyl vinyl ethers, alkyl vinyl ketones, .alpha.-olefins, isoolefins, butadiene, isoprene, dimethylbutadiene, acrybnithle, methacrylonitrile and the like.

[0043] It is desirable that the polymers used in the swellable layer of the containment pad of the invention contain a slight amount of cross-linking agent, preferably in the range of from about 0.01 to 2 percent by weight. The most efficient imbibition of organic liquid contaminants occurs when the level of cross-linking agent is less than about 1 percent since this permits the polymers to swell easily and imbibe a substantial volume of the organic hydrocarbon material.

[0044] Cross-linking agents which can be used in preparing the imbibing polymers suitable for use in the present invention include polyethylenically unsaturated compounds such as divinylbenzene, diethylene glycol dimethacrylate, diisopropenylbenzene, diisopropenyldiphenyl, diallylmaleate, diallylphthalate, allylacrylates, allylmethacrylates, allylfumarates, allylitaconates, alkyd resin types, butadiene or isoprene polymers, cyclooctadiene, methylene norbornylenes, divinyl phthalates, vinyl isopropenylbenzene, divinyl biphenyl, as well as any other di- or poly-functional compound known to be of use as a cross-linking agent in polymehca vinyl addition compositions. Normally, the polymer containing the cross-linking agent swells with the imbibed organic hydrocarbon material. If there is too much cross-linking agent, the imbibition takes an unreasonably long time or the polymer is unable to imbibe a sufficient quantity of the organic. If the imbibitional polymer contains no cross-linking agent or too little cross-linking agent, then it will dissolve eventually in the organic material resulting, for example, in a non-discrete, non-particulate mass of polymer-thickened organic liquid. However, for many applications where closure of a line is quickly noticeable uncross-linked material is satisfactory.

[0045] Swellable polymers for use in the present invention may be prepared by any convenient technique, either suspension, emulsion or mass polymerization. Generally, the method of preparation is selected to provide polymer in the most convenient form for any particular application. Thus, suspension polymerization is employed to provide a plurality of small beads. If it is desired to obtain a maximum amount of polymer surface and a relatively high permeability rate toward water carrying an organic liquid, it is oftentimes desirable to employ an emulsion polymerization technique and recover the polymer by spray drying. If it is desired to obtain a body of predetermined configuration, it is oftentimes beneficial to employ a mass polymerization technique wherein a polymer-insoluble diluent is employed. Techniques for the preparation of such porous polymers are disclosed in U.S. Pat. No. 3,322,695, the teachings of which are herewith incorporated by reference. Such porous polymers can also be prepared by either suspension or mass polymerization. Alternately, satisfactory layers may be prepared by mass or suspension polymerization with subsequent comminution of the polymer prepared by the mass technique. The particle size of such polymers is selected in accordance with the desired application. For most applications, such particles are from about 0.1 to 5 millimeters in diameter. Alternately, porous polymer layers may be polymerized in desired shapes in the manner of U.S. Pat. No. 3,322,695.

[0046] Further preferred examples of suitable swellable polymers that may absorb and imbibe organic hydrocarbons are as described in Hall et al., U.

S . patent No. 3, 750, 688, which on contact with the organic hydrocarbon substance, swell as it is absorbed or imbibed. A coating on a particulate material such as described in Larson et al., U. S. patent 4, 302, 337, may be employed. It may not be critical to employ a cross-linked polymer that swells but does not dissolve. However, cross-linked organic hydrocarbon liquidimbibing polymers are preferred. Suitable polymers include polymers of styrenes and substituted styrenes; copolymers of vinyl chloride including a copolymer of vinyl chloride and comonomers such as vinyl acetate, vinylidene chloride, acrylonitrile, methacrylonitrile, acrylates, methacrylates and acrylic polymers such as polymers of methylmethacrylate, ethyl acrylate. Particularly advantageous materials which respond to a wide variety of organic hydrocarbon liquids are the polymers of styrene such as polystyrene and copolymers of styrene and divinylbenzene containing up to ten weight percent divinylbenzene. For general use with aliphatic and aromatic hydrocarbons, and halogenated hydrocarbons, alkylstyrene polymers and copolymers are of particular benefit. Alkylstyrene polymers usually show substantial swelling in less than a minute when in contact with organic hydrocarbon liquids. Crosslinked polymers of styrenes, notably tertiary-alkylstyrenes, are used to advantage as the imbibing polymer. Those alkylstyrenes which can be used to prepare these imbibing polymers have alkyl groups having one to twenty, especially four to twelve, carbon atoms, examples of which include methylstyrene; ethylstyrene; dimethylstyrene; p-tert-butyl, m-tert-butyl, secbutyl, and/or iso-alkyl styrenes such as of butylstyrene; amlystyrene; hexylstyrene; octylstyrene to include 2-ethyl-hexylstyrene, iso-octylstyrene and di-t-butylstyrene; dodecylstyrene; octadecylstyrene; and eiscosylstyrene. Further, cross-linked copolymers of such alkylstyrenes as aforementioned and an alkyl ester derived from a one to twenty-four carbon alcohol and acrylic or methacrylic acid or mixture thereof. Suitable monomers which can be employed as comonomers with the alkylstyrene include such materials as vinylnaphthalene, styrene, alpha-methylstyrene, methylstyrene , methylstyrene, ring-substituted alpha-methylstyrenes , halostyrenes, arylstyrenes and alkarylstyrenes , methacrylic esters , acrylic esters , and cyclohexyl and isobornyl esters of acrylic and methacrylic acids ; esters and half esters of fumaric, maleic , itaconic acids ; vinyl biphenyls , alkyl vinyl ethers , alkyl vinyl ketones , alpha-olefins , iso-olefins , butadiene, isoprene, dimethylbutadiene , acrylonitrile, and methacrylonitrile. As previously described a slight amount of cross-linking agent can be contained in the polymer, say, in the range about from 0.01 to two percent by weight. A highly efficient imbibition of organic hydrocarbon liquid contaminants occurs when the level of cross-linking agent is less than about one percent by weight since this permits the polymers to swell easily and imbibe a substantial volume of the organic hydrocarbon material. Suitable cross-linking agents include polyethylenically unsaturated compounds such as divinylbenzene, diethylene glycol dimethacrylate, diisopropenylbenzene, diisopropenyldiphenyl, diallylmaleate, diallylphthalate, allylacrylates , allymethacrylates , allylfumarates , allylitaconates, alkyd resin type cross-linking agents , polybutadiene or polyisoprene polymers , cyclooctadiene, methylene norbornylenes , divinyl phthalates , vinyl isopropenylbenzene , divinyl biphenyl, as well as any other di- or polyfunctional compounds known to be of use as a cross-linking agent in polymeric vinyl addition polymer compositions . If there is too much cross-linking agent, the imbibition takes an unreasonably long time, or the polymer is unable to imbibe a sufficient quantity of the organic liquid, and interstitial spaces in the swellable layer are not completely closed when contacted with organic hydrocarbon. If the imbibitional polymer contains none or too little cross-linking agent, then it may well eventually dissolve or partially dissolve to a loose gel in the organic material resulting, for example, in a non-discrete, non-particulate mass of polymer-thickened organic liquid. However, for the present invention uncrosslinked material may be satisfactory under the minimal ambient pressure conditions associated with a containment device. Preferably, the swellable layer of the present invention comprises as absorbent IMBIBER BEADS® type of particles, which are made of lightly crosslinked alkylstyrene copolymers, and thus are hydrophobic and oleophilic in general, and appear to the naked eye as a powder, having a particle size distribution of about from forty to four hundred microns, for example, as available from Imbibitive Technologies Corp, USA.

[0047] Preferred swellable and/or reactive polymers for the middle layer of the containment pad are commercially available as Petroguard-D (Guardian Environmental technologies, USA), Imbiber Beads® (Imbibitive Technologies Corporation, USA), ZEP-O-ZORB (Zep Inc, Atlanta USA) and C.l. Agent polymer (CJ.Agent Solutions, Kentucky, USA). Materials such as PetroguardD, are highly preferred as they react with hydrocarbons to form a rubber like product; these are high capacity super absorbent polymers that instantly absorbs and solidifies oil and other hydrocarbons. These materials provide a highly effective plug in the containment pad of the present invention. In a preferred embodiment, the swellable polymer is in the form of a beads in the containment pad middle layer and are immobilized within a permeable matrix of preferably polymer material. In this arrangement, the particles are able to absorb and swell in contact with hydrocarbon materials but do not coalesce together in a localized plug but remain dispersed across the containment pad and ensure that the whole pad volume is filed with individually swollen absorbing and reacting polymer particles. Such a matrix also aids in the handling of the particulate polymer materials and the manufacture of the containment pad and device. This matrix material, whilst supporting the polymeric particles is of a form and density that it does not significantly inhibit the swelling of the particles and formation of the shut-off plug within the containment pad.

[0048] It should be understood that all and any aspects and embodiments as described herein may be combined in any number of combinations. Embodiments of the disclosure will become more fully apparent from the following detailed description, and the accompanying drawings in which like reference numerals identify similar or identical elements.

[0049] FIG. 1 shows a perspective view of the fluid collector according to the present invention;

[0050] FIG. 2 shows a top view of a fluid collector according to the present invention;

[0051] FIG. 3 shows a side view of a fluid collector according to the invention, [0052] FIG.4 shows a sectional view along the axis x, x’ identified in Figure 1 of a fluid collector of the present invention;

[0053] FIG. 5 shows the region A as indicated in Figure 4 of a fluid collector of the present invention, and [0054] FIG. 6 shows the region A as indicated in Figure 4 of a fluid collector of the present invention with primary and secondary absorbent/adsorbent indicated.

DETAILED DESCRIPTION [0055] As previously indicated under the disclosure of the invention the present invention relates to a fluid collector that provides a means for trapping and collecting accumulated occasional minor spillages or leaks and also to prevent wider loss of fluid under catastrophic leakage conditions due to for example liquid filing failures. One embodiment of this invention is described below with reference to the drawings.

[0056] With reference to Figure 1 the fluid collector (1) consists of upstanding side walls (2, 2’) secured to a fluid collection surface (3), located above this surface is a vehicle support means (4), which is this embodiment consists of a series of spaced apart angled metal struts (5) that are arranged transverse to the walls (2,2’) and are secured thereto. At either end of the collector (1) there is a section (6) of the vehicle support means (4) that may be opened by articulation around a pivot point (7) to expose the fluid collection surface (3) and a sump (8). The fluid collection surface (3) and the vehicle support means (4) are separated by a gap that is the primary separation region (9) which is a passage that traverses underneath the vehicle support means (4) for the full length of the vehicle support means (4). The primary absorbent/adsorbent that would be located in this passage and the secondary absorbent/adsorbent that would be located within the sump are not shown in this Figure. Also indicated are ramps (10, 10’) and fork lift guides (11. 1T).

[0057] With reference to Figure 2 the fluid collector (1) Is shown in plan view with the same features indicated as in Figure 1. In addition it can be seen that the fluid collection surface (3) is bisected in this embodiment along a central point (13). In addition the fluid collection surfaces (3) will slope upwards from their sump (3) ends towards a central apex (12). The primary absorbent/adsorbent material (not shown) will extend over the complete surface of the fluid collection surface (3).

[0058] With reference to Figure 3, the general side profile of the fluid collector (1) can be seen with the location of the apex (12) clearly indicated.

[0059] With reference to Figure 4, the general side profile in section of the fluid collector (1) ca been seem, which more clearly shows the primary absorption region (9) located between the vehicle support surface (4) and the fluid collection surface (3). Also, it can be seen are the angled metal struts (5) that span the upstanding side walls (2, 2’) and constitute the vehicle support surface (4). These features are evident in the expanded view of region A as illustrated in Figure 5, which also indicated the location of a drain point (14) from the sump (8). In Figure 6 the collector (1) is illustrated with the primary (15) and secondary (16) absorbent/adsorbents in-situ [0060] With reference to the Figures and particularly Figure 6, during use of the collector (1) a vehicle (not shown) will be stationary upon the support surface (4), which is in the form of metals struts (5) with the articulated section (6) closed in the down position. Any fuel that may be lost from the refueling activity of the vehicle will fall onto and through the support surface (4) and will impinge upon the primary absorbent/adsorbent (15) located within the primary separation region (9). This fuel will be absorbed/absorbed within the primary absorbent/adsorbent (15). Once the vehicle has been removed from the collector (1), the whole of the support surface (4) is exposed to the elements and if there is any precipitation such as rain this will fall upon the collector (1) and impinge upon the primary absorbent/adsorbent (15) containing fuel. This rain may flow off of the surface of the primary absorbent/adsorbent (15) and into the sump areas (8) and/or may pass through the primary absorbent/ adsorbent(15) and make contact with the collection surface (3) and flow along that surface and into the sump arrangements (8). In this passage from and/or through the primary absorbent/adsorbent (15) layer the water may pick up small levels of hydrocarbon or other organic fuel or oil components and this contaminated water is what enters the sump arrangements (8). This contaminated water will then pass through the secondary absorbent/adsorbent material (16) located within the sump (8) and the secondary absorbent/ adsorbent (16) will remove the low levels of oil/fuel contaminants present in the contaminated water before it exits the sump (8) at the drain point (14).

[0061] All of the features disclosed in this specification for each and every embodiment (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Claims

1. A fluid collector comprising a vehicle support surface and a fluid collection surface that comprises an impermeable collection surface floor with upstanding walls at two opposing edges of the floor and a sump arrangement located at one or more of the transverse opposing edges.

2. A fluid collector as claimed in claim 1, wherein the sump arrangements have the majority but not all of their volume located below the plane of the collection surface.

3. A fluid collector as claimed in any one of the preceding claims, wherein the upstanding walls continue into the sump arrangements to provide the upper wall surfaces of the sump arrangements.

4. A fluid collector as claimed in any one of the preceding claims, wherein the effective bottom surface of the support surface defines a primary separation region with the collection surface, this region being located between the effective bottom surface of the support surface and the contact surface.

5. A fluid collector as claimed in claim 4, wherein a primary separation material is located within the primary separation region.

6. A fluid collector as claimed in claim 1, having a vehicle or equipment support means and one region of that means is removable or may be opened to expose in part the primary separation region.

7. A fluid collection device as claimed in any one of the preceding claims, wherein the collection surface floor is sloped towards the sump arrangement.

8. A fluid collection device as claimed in any one of the preceding claims, wherein the sump arrangements comprise one or more secondary separation materials.

9. A fluid collection device as claimed in any one of the preceding claims, wherein the sump arrangements comprise one or more openings that allow some liquid to pass out of the sump.

10. A fluid collection device as claimed in claim, wherein the secondary absorbent/adsorbent is in the form of a sponge or foam or nonwoven material that is formed and shaped to fit tightly within the sump.

11. A fluid collector as claimed in claim 5, wherein the primary separation material is an absorbent/adsorbent material is in the form of a web.

12. A fluid collector as claimed in claim 11, herein the web is a nonwoven material in the form of a polypropylene based felt material.