GB2539376A

GB2539376A - Apparatus for separating hydrocarbons from a liquid

Info

Publication number: GB2539376A
Application number: GB1507088.1A
Authority: GB
Inventors: Edward Sacree Richard
Original assignee: ADLER & ALLAN Ltd
Current assignee: ADLER & ALLAN Ltd
Priority date: 2015-04-27
Filing date: 2015-04-27
Publication date: 2016-12-21
Anticipated expiration: 2035-04-27
Also published as: GB201507088D0; GB201718655D0; GB2539376B; GB2555540B; GB2555540A

Abstract

An apparatus for separating hydrocarbons from a liquid, comprises a housing having at least one housing inlet 118 and at least one housing outlet 120 located in a lower portion of the housing. At least one separation chamber 128 is disposed in the housing in fluid communication with the at least one housing inlet 118 and the at least one housing outlet 120. At least one support surface 136 is located in the separation chamber 128 for supporting a filter assembly (600, Fig 6) having a filter inlet region (608, 610, Fig 6) and a filter outlet region such that, in use, the at least one housing inlet is in fluid communication with the filter inlet region and the filter outlet region is in fluid communication with the at least one housing outlet. The apparatus may be used to separate hydrocarbons such as oil from a liquid such as surface water to enable separated water to enter drainage systems and the water course. A further invention directed to a filter assembly for a hydrocarbon separator is also disclosed.

Description

APPARATUS FOR SEPARATING HYDROCARBONS FROM A LIQUID

Field of the Invention

The present invention relates to apparatus for separating a hydrocarbon/s from a liquid. In particular, but not exclusively, the present invention relates to an oil separator and a filter assembly for use in such a separator for separating oil from a liquid, such as water, to enable the water to safely enter a drainage system and/or the water course.

A conventional oil separator is typically installed below ground and connected into surface water drainage systems to enable otherwise contaminated surface water to safely enter a drainage system and/or watercourse and thus protect the environment from pollution by oils for example. Conventional oil separators are typically used, for example, in forecourts of vehicle fuelling stations or with bund systems surrounding high voltage electrical transformers in substation compounds, to separate oil from water and contain any run-off oil leaks from vehicles, plant machinery and/or aboveground storage tanks, or accidental spillages, until the oil is safely removed. Oil separators are interchangeably known as oil interceptors. As used herein, the term 'separator' includes separators and interceptors.

Conventional separators are employed to arrest the flow of oil leaks or spillage into the environment by physically preventing the 'oil' phase from entering the aqueous waste stream. Coalescent filters are known in the art that are manufactured to fit into separators. Such coalescent filters work on the principle that when two liquids are immiscible or not soluble in each other, they can form an emulsion or a colloidal suspension. In these types of mixtures the dispersed liquid (water) forms droplets in the continuous phase (oil or fuel). For example, in a water/ transformer oil mixture, the transformer oil is in the continuous phase and the water will exist as droplets of various sizes.

Conventional separators include gravity separators which are used in liquid-liquid systems to promote the coalescing of the dispersed phase. In these systems, the differences in the densities of the two liquids cause droplets to rise or fall according to -2 -their buoyancy. The greater the differences in densities the easier the separation is, as rising or falling droplets (water) are acted upon by frictional forces exerted by the viscosity of the continuous phase. This mechanism is governed by Stoke's Law. When the movement of the continuous phase (oil or diesel fuel) is slow, as in a gravity settler, the effect of the inertial force is reduced and the buoyant force and the gravity force are equal. This is termed as the terminal velocity droplet. A critical factor in a gravity (static) settler is the residence time. It has to be long enough to allow for the passive process of merging smaller droplets into larger ones.

A conventional oil separator includes a relatively large cylindrical separation tank having an inlet at one end and an outlet at the other end. The inlet and outlet are both located on top of the tank or proximal an upper surface of the tank such that the inlet and outlet extend above ground level for connecting respective inlet and outlet pipes thereto. A conventional separator tank typically has a diameter of about around 1026mm, an overall length of about around 2319mm and an overall height of about around 1655mm including a raised inspection turret. The separator includes a filter assembly mounted on a docking structure located in the base of the separation tank. The filter assembly is typically cylindrical and oriented on one end on the docking structure. Surface water flows under gravity or by pumping directly into the tank and, zo when at a certain level above the docking structure, flows through a filter element located inside the filter assembly. The filtered water then flows down through an opening in the docking structure which is coupled by a pipe to the outlet which is connected to a drainage system or the watercourse. The operating liquid level in the tank is at the top of the tank for the filtered water to exit the outlet located at the top of the tank.

An automatic closure device (ACD) is typically located in the tank to automatically prevent water exiting the tank via the outlet when a maximum threshold amount/level of oil is present in the tank. The ACD may be located outside or inside the filter assembly and typically comprises a ball valve mechanism to close the opening in the docking structure in the event of excess oil in the tank, i.e. low levels of water, to prevent excess oil exiting the tank via the outlet. The separator also typically includes an oil probe for detecting a maximum threshold level of oil in the tank and a silt probe -3 -for detecting the presence of silt in the tank. Each probe typically activates an alarm when excess oil or silt is detected in the tank. The separator may also include an access cover for inspecting the condition of the filter and/or an oil level in the tank and/or taking a sample of liquid in the tank and/or maintaining/replacing the filter element or ACD.

However, in view of the required size of a conventional separator, and thus the distance from the access cover to the bottom of the tank, the ACD and/or filter assembly is not always visible for sufficient inspection and a faulty or blocked ACD may not be detected resulting in oil exiting the tank via the outlet and undesirably entering the drainage system or watercourse. In view of the required size of conventional separators to achieve the necessary residence time, conventional separators are also difficult and expensive to transport, store, handle and install. They also require expensive and time consuming excavation and lifting gear to be installed below ground, e.g. in a fuelling station forecourt or a high voltage electrical substation compound. Furthermore, conventional filter assemblies typically include a so-called 'block form' filter which is known to block easily in the presence of silt before excess silt is detected by a silt probe. Other conventional filter assemblies include so-called 'wrap around' filters which are prone to the ingress of oil between the upper plate and cylindrical side wall of the filter body. Conventional filter assemblies also include a filter body which is generally tubular and having a number of slotted apertures therein in an attempt to reduce the risk of blocking. However, such slotted apertures tend to compromise the integrity and strength of the filter assembly. Conventional filter assemblies are also difficult to handle particularly when lowering towards or lifting away from the docking structure located in the bottom of a conventional separator tank.

In addition, the close proximity of high voltage cables, both below ground and above ground cables, within a constricted high voltage electrical substation compound for example often prohibits the installation of a conventional separator. -4 -

Summary of the Invention

It is an aim of the present invention to at least partly mitigate the above-mentioned problems.

It is an aim of certain embodiments of the present invention to provide an oil separator that is relatively small and easy to transport, store, handle and install, whilst ensuring the required residence time is achieved for efficient and safe separation.

It is an aim of certain embodiments of the present invention to provide an oil separator that can be installed on or above ground level whilst being a gravity separator without any moving parts such that the separator requires little maintenance.

It is an aim of certain embodiments of the present invention to provide an oil separator that can be installed on or above ground level and which minimises the amount of pipework required to connect the separator to a drainage system or water course.

It is an aim of certain embodiments of the present invention to provide an oil separator is lightweight whilst being relatively rigid and strong.

It is an aim of certain embodiments of the present invention to provide a filter assembly for an oil separator that is relatively strong and easy to handle, has a reduced risk of blocking/silting, whilst ensuring maximum oil separation efficiency and required flow levels are maintained.

According to a first aspect of the present invention there is provided apparatus for separating hydrocarbons from a liquid, comprising: a housing having at least one housing inlet and at least one housing outlet; at least one separation chamber disposed in the housing in fluid communication with the at least one housing inlet and the at least one housing outlet; and at least one support surface located in the separation chamber for supporting a filter assembly having a filter inlet region and a filter outlet region such that, in use, -5 -the at least one housing inlet is in fluid communication with the filter inlet region and the filter outlet region is in fluid communication with the at least one housing outlet; wherein the at least one housing outlet is located in a lower portion of the housing.

Aptly, the at least one housing inlet is located in an upper portion of the housing.

Aptly, the at least one housing outlet is located proximal a base region of the housing.

Aptly, the housing is substantially elongate and the at least one housing inlet is disposed in a first end wall of the housing and the at least one housing outlet is disposed in a further end wall of the housing.

Aptly, the apparatus further comprises a first partitioning member extending between opposed side walls of the housing to define an outlet chamber located downstream of the separation chamber.

Aptly, the first partitioning member comprises a first aperture to couple at least one opening in the support surface in fluid communication with the outlet chamber.

Aptly, the first aperture is located at the base region of the housing.

Aptly, the support surface is spaced apart from a base region of the housing to define at least one plenum below the support surface such that the at least one opening in the support surface is in fluid communication with the first aperture of the first partitioning member.

Aptly, the support surface extends substantially horizontally from the first partitioning 30 member partially along the separation chamber towards the at least one housing inlet. -6 -

Aptly, the support surface extends between the opposed side walls of the housing and at least one wall portion extends substantially downwardly from the support surface to the base region of the housing.

Aptly, the apparatus further comprises at least one baffle member located in the outlet chamber and extending substantially upwardly from the base region of the housing and spaced apart from an upper edge region of the housing.

Aptly, the apparatus further comprises a further partitioning member extending between the opposed side walls of the housing to provide an inlet chamber located upstream of the separation chamber.

Aptly, the further partitioning member comprises a further aperture to couple the at least one housing inlet in fluid communication with the separation chamber.

Aptly, the further aperture is located at the base region of the housing.

Aptly, a volume of the separation chamber is greater than a volume of each of the inlet chamber and the outlet chamber.

Aptly, the volume of the separation chamber is about around twice the volume of each of the inlet chamber and the outlet chamber.

Aptly, the first and further partitioning members extend from a base region of the housing to an upper edge region of the housing.

Aptly, the housing comprises at least one removable lid portion to gain access to at least the separation chamber.

According to a second aspect of the present invention there is provided a filter assembly for a hydrocarbon separator, comprising: a hollow support body having a wall portion extending substantially downwardly from an upper portion of the support body, wherein a lower portion of the support body defines a filter outlet region and at least one aperture disposed in at least one of the wall portion and the upper portion defines a filter inlet region; and -7 -at least one filter element located on an outer surface of the support body at the filter inlet region.

Aptly, the at least one aperture comprises a first set of spaced apart apertures in the wall portion and a further set of spaced apart apertures in the upper portion, and the at least one filter element extends substantially over the wall portion and the upper portion.

Aptly, the first set of apertures in the wall portion each have a diameter that is greater than a diameter of each of the further set of apertures in the upper portion.

Aptly, each of the first set of apertures has a diameter of about around 50mm and each of the further set of apertures has a diameter of about around 30mm.

Aptly, the support body and the at least one filter element are substantially cylindrical and arranged concentrically with respect to each other.

Aptly, the filter assembly further comprises a handle portion for handling the filter assembly.

Aptly, the filtering element comprises a reticulating foam material.

According to a third aspect of the present invention there is provided a system for separating hydrocarbons from a liquid, comprising apparatus according to the first aspect of the present invention and at least one filter assembly according to the second aspect of the present invention.

Aptly, the system further comprises a pump coupled to the housing inlet of the apparatus by a first conduit.

Aptly, the system further comprises a further conduit coupling the housing outlet of the apparatus to a drainage system and/or watercourse. -8 -

According to a fourth aspect of the present invention there is provided apparatus substantially as described herein with reference to the accompanying drawings.

According to a fifth aspect of the present invention there is provided a filter assembly substantially as described herein with reference to the accompanying drawings.

Brief Description of Drawings

Embodiments of the present invention will now be described hereinafter, by way of example only, with reference to the accompanying drawings in which: Figure 1 illustrates an isometric view of an oil separator including a removable lid according to certain embodiments of the present invention; Figure 2 illustrates an isometric wireframe view of the oil separator of Figure 1; Figure 3 illustrates a plan view of the oil separator of Figure 1 with the lid removed; Figure 4 illustrates section B-B of the oil separator of Figure 3; zo Figure 5 illustrates section A-A of the oil separator of Figure 3; and Figure 6 illustrates a cross section through a filter assembly in accordance with the certain embodiments of the present invention.

Description of Embodiments

In the drawings like reference numerals refer to like parts.

Figure 1 illustrates an oil separator 100 according to certain embodiments of the present invention for separating hydrocarbons (oil) from a liquid such as surface water.

The separator 100 includes a substantially rectangular box housing 102 having a base 104, a pair of spaced apart and opposed side walls 105,106 and a pair of spaced apart and opposed end walls 107,108. The housing 102 includes a peripheral flange 110 that outwardly extends from an upper edge region 112 of the housing. The flange -9 -includes a number of holes 114 for removably attaching a lid 116 to the housing for preventing the ingress of water or dirt into the housing whilst enabling access into the housing for inspection and maintenance purposes.

As illustrated in Figures 2 to 5, the separator 100 includes a housing inlet 118 located in one end wall 107 of the housing 102 and proximal the upper edge region 112 of the housing 102 for connecting an inlet conduit (not shown) to. The inlet conduit may couple the housing inlet 118 to a pump located in a sump, for example, of a drainage system that protects an area at risk to contaminated surface water and/or accidental leaks and spillages. The separator 100 includes a housing outlet 120 located in the other end wall 108 of the housing 102 and proximal the base 104 of the housing 102. The housing outlet 120 of the separator as shown in the Figures is located at a lowermost point of the end wall 107 such that only a relatively small step up from the base 104 to the outlet 120 exists. The separator 100 includes two substantially parallel partitioning members 122, 124 that extend substantially laterally between the side walls 105,106 of the housing and extend substantially vertically up from the base 104 to the upper edge region 112 of the housing. The partitioning members 122, 124 divide an internal space of the housing 102 into an inlet chamber 126, a separation chamber 128 and an outlet chamber 130. Each partitioning member 122,124 has a slotted aperture 132,134 at its lower edge to allow liquid to pass under the partitioning member 122,124 and into the respective downstream chamber.

A support surface 136 extends substantially horizontally from the 'downstream' partitioning member 124 in an upstream direction towards the housing inlet 118. The support surface 136 extends between the side walls 105,106 of the housing 102 and a substantially vertical support member 138 extends from an upstream edge of the support surface 136 to the base 104 of the housing 102. The support surface 136 is raised above the base 104 of the housing 102 to define a plenum 140 under the support surface 136. The support surface 136 has at least one centrally located opening 142 such that the separation chamber 128 is in fluid communication with the plenum 140 and liquid can only enter the plenum 140 from the separation chamber 128 via the opening 142 in the support surface 136. The raised plenum 140 allows -10 -suitable storage capacity for settled silts without affecting the operational function of the apparatus and in particular the filter assembly 600 further described below.

Any one or more of the slotted apertures 132,134 of the partitioning members 122,124 and the opening 142 in the support surface 136 may include a mesh-like structure to prevent silt or other debris entering into a downstream one of the chambers 128,130 or the plenum for example.

The support surface 136 acts as a docking platform for mounting a filter assembly 600 as shown for example in Figure 6. The support surface 136 may be any suitable shape and size for mounting a filter assembly above the base 104 of the housing 102 and to define the plenum 140 below the support surface 136. For example, the docking platform may be substantially box-like wherein the support surface 136 does not extend the entire width of the housing and instead includes straight or curved side wall portions that extend downwardly from edges of the support surface to the base of the housing. Equally, the at least one opening 142 in the support surface 136 may be any suitable size and shape that allows liquid to flow from the separation chamber, through the filter assembly 600 located over the opening 142 and into the plenum 140. The support surface 136 includes a projecting portion 137 for engaging a lower portion of the filter assembly 600 to retain the filter assembly on the support surface 136 at least in a horizontal direction. Alternatively, the support surface 136 may include a recessed portion (not shown) that corresponds in shape with a lower portion of the filter assembly to receive the filter assembly 600 when docked on the support surface 136. The projecting portion 137 or recess may be any suitable shape to correspond with a shape of the filter assembly. For example, where the filter assembly is substantially cylindrical, the projecting portion 137 or recess may be substantially circular. A substantially circular projecting portion 137 aptly has a diameter that is slightly smaller than a diameter of the filter assembly 600 such that a substantially cylindrical lower portion of the filter assembly is mounted over and around the projecting portion. The projecting portion 137 (spigot) is aptly sized relative to a lower end region (socket) of the filter assembly 600 such that an interface fit is achieved to securely locate the filter assembly 600 on the support surface 136. Alternatively, the lower end region of the filter assembly may act as the spigot and the projecting portion 137 may be sized to act as the socket of such an arrangement.

A filter assembly 600 according to certain embodiments of the present invention is shown in Figure 6. The filter assembly 600 has a support body 602 comprising a substantially cylindrical wall portion 604 and an upper disc-shaped portion 606. The upper portion 606 may be attached by welding or the like to the wall portion 604 or the wall portion 604 and upper portion 606 may be integral. The support body 602 is a plastics material, such as PVC, but may be any suitable material such as aluminium, steel or the like. The support body 602 has an external diameter of about around 205mm and a wall thickness of about around 2.5mm. The height of the support body is about around 345mm. The wall portion 604 and the upper portion 606 each include a plurality of spaced apart through holes 608,610. The through holes 608,610 are substantially circular but may be any suitable shape to allow liquid into the central space 612 of the filter assembly 600. The through holes 608 in the wall portion 604 each have a diameter of about around 50mm and the through holes 610 in the upper portion 606 each have a diameter of about around 30mm. Aptly there are about around eight through holes 608 located around the wall portion 604 and about around four through holes 610 located in the upper portion 606. The through holes 608,610 define an inlet region of the filter assembly 600 for liquid to enter into the central space 612 of the filter assembly 600. An open lower region 613 of the filter assembly 600 defines an outlet region of the filter assembly 600 for liquid to exit the central space 612 and enter into the plenum 140 via the opening 142 in the support surface 136 of the separator 100, as described further below.

The filter assembly 600 includes a filter element 614 located substantially over an outer surface 615 of the support body 602. The filter element 614 comprises a sleeve portion 616 located around the wall portion 604 and a disc portion 618 located on the upper portion 606 of the support body 602. The sleeve portion 616 and disc portion 618 are concentrically arranged on the support body 602 with respect to a longitudinal axis 619 of the filter assembly 600. The sleeve portion 616 and disc portion 618 may be formed separately and adhered together, for example, or may be integrally formed. The sleeve portion 616 and disc portion 618 each have a thickness of about around -12 - 50mm and an outer diameter of about around 305mm. The sleeve portion 616 has a height of about around 340mm.

The filter element 614 aptly comprises a polyether foam material and may include one or more layers. The filter assembly 600 as shown in Figure 6 is one possible embodiment of the filter assembly that may be utilised in the separator according to certain embodiments of the present invention. For example, the filter assembly 600 may be constructed as multiple layers using reticulated polyester foam and/or reticulated polyester foam impregnated with activated carbon and may take the form of the coalescing filter as described in the International patent application W02015/015192 A1.

The filter assembly 600 further includes a handle 620 for handling the filter assembly such as when lowering the filter assembly on to the support surface 136 of the separator 100 or when lifting the filter assembly out of the separator for maintenance or replacement. The handle 620 includes a shaft portion 622 extending substantially downwardly from an upper grip portion 624 which may be a plate-like member or a rod-like member oriented substantially perpendicularly to the shaft portion 622. A user grips the grip portion 624 when handling the filter assembly. The handle 620 also includes an outwardly extending lower portion 626 which abuts an inner surface 628 of the upper portion 606 of the support body 602. The shaft portion 616 is slidably located in a central aperture 626 that extends through the upper portion 606 and disc portion 618 such that the handle 620 can be slidably moved between a retracted position when the filter assembly is not being handled and a deployed position when the filter assembly is being handled. A plate-like grip portion 624 aptly closes the central aperture 626 when the handle 620 is in the retracted position. An alternative embodiment of the handle 620 may comprise a curved strip of material, such as aluminium, steel or plastic, or the like, that is attached at each end by welding, mechanical fasteners or the like to the wall portion 602 of the support body 602. The handle may be a suitable material, such as a plastic or stainless steel. The coalescing filter components 616,618 are aptly preassembled then bonded to ensure that there is no risk of possible cross contamination of hydrocarbon being discharged.

-13 -The outlet chamber 130 of the separator 100 includes a baffle member 144 extending laterally between the side walls 105,106 of the housing 102 and substantially vertically towards the upper edge region 112 of the housing. An upper edge of the baffle member 144 is located in an upper half of the housing whilst being spaced apart from the upper edge region of the housing. A working level of liquid in the separator 100 is about around the level of the upper edge of the baffle member 144 which acts as a choke to ensure the correct flow rate through the separator and desired residence time is achieved for maximum separation efficiency for the reduced volume of the oil separator 100 in accordance with certain embodiments of the present invention.

The separator 100 aptly also includes one or more oil, silt and/or liquid sensors (not shown) to detect a predetermined threshold level of oil and water in the separator and an undesirable build-up of silt in the base of the housing respectively. One or both of the oil and silt sensors may be connected to an alarm which is sounded when a predetermined level of oil or silt is detected in the separator. In addition, each sensor may be connected to a controller that automatically stops a pump located in a sump, for example, of a drainage system located upstream of the separator to prevent further liquid being pumped into the separator.

In use, contaminated surface water, for example, enters the inlet chamber 126 via the housing inlet 118 and impacts the upstream partitioning member 122 which acts as a baffle to direct the contaminated water towards the base 104 of the housing 102 by displacement whilst preventing excessive turbulence which would otherwise undesirably mix the hydrocarbons (oil) and water together in the inlet chamber 126 which in turn would adversely affect the separation process. The contaminated water then passes into the separation chamber 128 via the slotted aperture 132 in the upstream partitioning member 122. When at a predetermined level, the contaminated water in the separation chamber 128 flows through the filter assembly, e.g. 600, where separation of oil from water occurs. Clean water exits the filter assembly 600 and passes through the opening 142 in the support surface 136 of the docking platform to thereby enter the plenum 140. The clean water then flows from the plenum 140 through the slotted aperture 134 in the downstream partitioning member 124 and into the outlet chamber 130. The clean water in the outlet chamber 130 weirs over the baffle member 144 which retains the required capacity of the system, particularly upstream in the separation chamber 128. Clean and safe water then flows from the separator via the housing outlet 120 to a drainage system or the watercourse.

In accordance with certain embodiments of the present invention, the partitioning members 122, 124 and baffle member 144 increase the rigidity and structural strength of the housing 102. The upstream partitioning member 122 acts as a first baffle to urge liquid entering the housing 102 via the inlet 118 towards the base 104 of the lo housing 102 without causing turbulence. The relative dimensions of each chamber ensures a residence time of about around 6 minutes, or a flow rate through the separator of about around 6 litres per second, is achieved for maximum separation efficiency. The outlet baffle member 144 acts as a further baffle or choke to ensure a predetermined capacity of the separator and desired flow rate therethrough is achieved. This in turn ensures the desired residence time is achieved for efficient separation whilst minimising the overall size and weight of the separator. The baffle member 144 is sized such that filtered water in the outlet chamber 130 weirs over the baffle member before exiting the separator via the housing outlet 120 located at the base 104 of the housing 104. This allows for a sample of filtered water to be easily taken from the outlet chamber after removing the lid 116 from the separator 100. The lid 116 may aptly include a separate access cover (not shown) which is located above the outlet chamber 130 for quick and easy access to the outlet chamber 130 without having to remove the entire lid 116 from the housing 104. The baffle member 144 also allows the housing outlet 120 to be located at or proximal to the base of the housing which in turn reduces the length of pipe required to connect the separator to a drainage system or water course and also reduces a bend radius of, and therefore stress on, a pipe connected to the housing outlet which would otherwise be relatively high for an outlet pipe connected to a housing outlet undesirably located proximal an upper edge of the separator.

The size, dimensions and arrangement of the separator according to certain embodiments of the present invention are aptly suitable to meet the current code of practice PPG3 whilst ensuring the size and weight of the separator are minimised and -15 -the efficiency of separation is maximised. Example dimensions of the separator as illustrated in the Figures will be now described which is based on a flow rate to the separator of about around 0.125 litres/second and about around 50mm rainfall and to provide a retention time of about around 6 minutes for efficient separation.

The housing 102 aptly has a height of about around 610mm, a width of about around 550mm and a length of about around 1025mm. The wall thickness of the housing 102 is about around 5mm. The lid 116 aptly has a width of about around 550mm and a length of about around 1125mm. The inlet 118 is located about around 460mm above lo the base 104 of the housing and centrally located between the side walls 105,106 of the housing. The outlet 120 is located about around 10mm above the base 104 of the housing and centrally located between the side walls 105,106 of the housing. The inlet 118 has an outer diameter of about around 25mm and a length of about around 80mm. The outlet 120 has an outer diameter of about around 50mm and a length of about around 80mm.

The inlet chamber 126 aptly has a length of about around 205mm, the separation chamber 128 aptly has a length of about around 574mm, and the outlet chamber 130 aptly has a length of about around 246mm. The upstream and downstream partitioning members 122,124 both have a height of about around 610mm and a width of about around 450mm. The slotted apertures 132,134 in each partitioning member 122,124 has a width of about around 310mm and a height of about around 55mm. The outlet baffle member 124 has a height of about around 435mm and a width of about around 450mm.

The support surface 136 aptly has a length of about around 355mm and is raised above the base 104 of the housing 102 by about around 100mm. The projecting portion 137 aptly is about around 30mm high and has an internal diameter of about around 205mm. The opening 142 in the support surface 136 has a diameter of about around 180mm.

The housing and partitioning/baffle members may all be made from the same material or a combination of different materials. For example, the housing may be a metals -16 -material, such as stainless steel or aluminium or the like, and the partitioning/baffle members may be formed from a plastics material such as glass reinforced polyester or polyethylene or the like, or vice versa. Aptly, the separator according to certain embodiments of the present invention is made of the same material which is aptly a plastics material, such as GRP or polyethylene.

Certain embodiments of the present invention may therefore provide apparatus for separating hydrocarbons from a liquid that is relatively small, lightweight and structurally strong. Certain embodiments of the present invention may provide a separator that is easy to install on or above ground level and which is easy to repair, maintain and inspect. The arrangement of the apparatus according to certain embodiments of the present invention may ensure an optimum liquid retention time is achieved for maximum separation efficiency, whilst minimising the size and weight of the apparatus and allowing the apparatus to support and protect a wide range of surface areas and applications. The apparatus according to certain embodiments of the present invention may also reduce the amount of connecting pipework and stresses subjected thereto in use.

Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to" and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Features, integers, characteristics or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (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 the features and/or steps are mutually exclusive. The invention -17 -is not restricted to any details of any foregoing embodiments. The invention extends to any novel one, or novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

Claims

-18 -CLAIMS: 1. Apparatus for separating hydrocarbons from a liquid, comprising: a housing having at least one housing inlet and at least one housing outlet; at least one separation chamber disposed in the housing in fluid communication with the at least one housing inlet and the at least one housing outlet; and at least one support surface located in the separation chamber for supporting a filter assembly having a filter inlet region and a filter outlet region such that, in use, the at least one housing inlet is in fluid communication with the filter inlet region and the filter outlet region is in fluid communication with the at least one housing outlet; wherein the at least one housing outlet is located in a lower portion of the housing.
2. The apparatus as claimed in claim 1, wherein the at least one housing inlet is located in an upper portion of the housing.
3. The apparatus as claimed in claim 1 or 2, wherein the at least one housing outlet is located proximal a base region of the housing.
4. The apparatus as claimed in any preceding claim, wherein the housing is substantially elongate and the at least one housing inlet is disposed in a first end wall of the housing and the at least one housing outlet is disposed in a further end wall of the housing.
5. The apparatus as claimed in any preceding claim, further comprising a first partitioning member extending between opposed side walls of the housing to define an outlet chamber located downstream of the separation chamber.

-19 -
6. The apparatus as claimed in claim 5, wherein the first partitioning member comprises a first aperture to couple at least one opening in the support surface in fluid communication with the outlet chamber.
7. The apparatus as claimed in claim 6, wherein the first aperture is located at the base region of the housing.
8. The apparatus as claimed in claim 6 or 7, wherein the support surface is spaced apart from a base region of the housing to define at least one plenum below the support surface such that the at least one opening in the support surface is in fluid communication with the first aperture of the first partitioning member.
9. The apparatus as claimed in claim 8, wherein the support surface extends substantially horizontally from the first partitioning member partially along the separation chamber towards the at least one housing inlet.
10. The apparatus as claimed in claim 9, wherein the support surface extends between the opposed side walls of the housing and at least one wall portion extends substantially downwardly from the support surface to the base region of the housing.
The apparatus as claimed in any of claims 5 to 10, further comprising at least one baffle member located in the outlet chamber and extending substantially upwardly from the base region of the housing and spaced apart from an upper edge region of the housing.
12. The apparatus as claimed in any of claims 5 to 11, further comprising a further partitioning member extending between the opposed side walls of the housing to provide an inlet chamber located upstream of the separation chamber.

-20 -
13. The apparatus as claimed in claim 12, wherein the further partitioning member comprises a further aperture to couple the at least one housing inlet in fluid communication with the separation chamber.
14. The apparatus as claimed in claim 13, wherein the further aperture is located at the base region of the housing.
15. The apparatus as claimed in any of claims 12 to 14, wherein a volume of the separation chamber is greater than a volume of each of the inlet chamber and the outlet chamber.
16. The apparatus as claimed in claim 15, wherein the volume of the separation chamber is about around twice the volume of each of the inlet chamber and the outlet chamber.
17. The apparatus as claimed in any of claims 12 to 16, wherein the first and further partitioning members extend from a base region of the housing to an upper edge region of the housing.
18. The apparatus as claimed in any preceding claim, wherein the housing comprises at least one removable lid portion to gain access to at least the separation chamber.
19. A filter assembly for a hydrocarbon separator, comprising: a hollow support body having a wall portion extending substantially downwardly from an upper portion of the support body, wherein a lower portion of the support body defines a filter outlet region and at least one aperture disposed in at least one of the wall portion and the upper portion defines a filter inlet region; and at least one filter element located on an outer surface of the support body at the filter inlet region.

-21 -
20. The filter assembly as claimed in claim 19, wherein the at least one aperture comprises a first set of spaced apart apertures in the wall portion and a further set of spaced apart apertures in the upper portion, and the at least one filter element extends substantially over the wall portion and the upper portion.
21. The apparatus as claimed in claim 20, wherein the first set of apertures in the wall portion each have a diameter that is greater than a diameter of each of the further set of apertures in the upper portion.
22. The apparatus as claimed in claim 21, wherein each of the first set of apertures has a diameter of about around 50mm and each of the further set of apertures has a diameter of about around 30mm.
23. The filter assembly as claimed in any of claims 19 to 22, wherein the support body and the at least one filter element are substantially cylindrical and arranged concentrically with respect to each other.
24. The filter assembly as claimed in any of claims 19 to 23, further comprising a handle portion for handling the filter assembly.
25. The filter assembly as claimed in any of claims 19 to 24, wherein the filtering element comprises a reticulating foam material.
26. A system for separating hydrocarbons from a liquid, comprising apparatus as claimed in any of claims 1 to 18 and at least one filter assembly as claimed in any of claims 19 to 25.
27. The system as claimed in claim 26, further comprising a pump coupled to the housing inlet of the apparatus by a first conduit.
28. Apparatus substantially as described herein with reference to the accompanying drawings.-22 -
29. A filter assembly substantially as described herein with reference to the accompanying drawings.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWSCLAIMS: 1. Apparatus for separating hydrocarbons from a contaminated liquid, comprising: a housing having a base region, first and further opposed end regions, first and further opposed side regions, at least one housing inlet for contaminated liquid to enter the housing and at least one housing outlet for decontaminated liquid to exit the housing, wherein the at least one housing inlet is located in an upper portion of the first end region relative to the base region, and the at least one housing outlet is located in the further end region and proximal the base region; at least one separation chamber disposed in the housing in fluid communication with the at least one housing inlet and the at least one housing outlet; at least one support surface located in the separation chamber for supporting a filter assembly having a filter inlet region and a filter outlet region, the at least one support surface comprising at least one opening such CD that, in use, the at least one housing inlet is in fluid communication with the filter inlet region and the filter outlet region is in fluid communication with the at least one housing outlet; a first partitioning member extending substantially upwardly from the base region and between the first and further opposed side regions of the housing to define an outlet chamber located downstream of the separation chamber and comprising a first aperture located proximal the base region of the housing to couple the at least one opening in the support surface in fluid communication with the outlet chamber; a further partitioning member extending substantially upwardly from the base region and between the first and further side regions of the housing to define an inlet chamber located upstream of the separation chamber and comprising a further aperture located proximal the base region of the housing to couple the at least one housing inlet in fluid communication with the separation chamber; and at least one baffle member located in the outlet chamber and extending substantially upwardly from the base region and between the first and further side regions of the housing.2. The apparatus as claimed in claim 1, wherein the housing is substantially elongate and the at least one housing inlet is disposed in a first end wall of the housing and the at least one housing outlet is disposed in a further end wall of the housing.3. The apparatus as claimed in claim 1 or 2, wherein the first aperture is located at the base region of the housing.4. The apparatus as claimed in any preceding claim, wherein the support surface is spaced apart from the base region of the housing to define at least one plenum below the support surface such that the at least one opening in the support surface is in fluid communication with the first aperture of the first partitioning member.5. The apparatus as claimed in claim 4, wherein the support surface extends substantially horizontally from the first partitioning member partially along the separation chamber towards the at least one housing inlet.6. The apparatus as claimed in claim 5, wherein the support surface extends between opposed side walls of the housing and at least one wall portion extends substantially downwardly from the support surface to the base region of the housing.7. The apparatus as claimed in any preceding claim, wherein the at least one baffle member is spaced apart from an upper edge region of the housing.8. The apparatus as claimed in any preceding claim, wherein the further aperture is located at the base region of the housing.9. The apparatus as claimed in any preceding claim, wherein a volume of the separation chamber is greater than a volume of each of the inlet chamber and the outlet chamber.10. The apparatus as claimed in claim 9, wherein the volume of the separation chamber is substantially twice the volume of each of the inlet chamber and the outlet chamber.The apparatus as claimed in any preceding claim, wherein the first and further partitioning members extend from the base region of the housing to an upper edge region of the housing.12. The apparatus as claimed in any preceding claim, wherein the housing comprises at least one removable lid portion to gain access to at least the separation chamber.13. A system for separating hydrocarbons from a liquid, comprising apparatus as O claimed in any of claims 1 to 12 and at least one filter assembly.14. The system as claimed in claim 13, further comprising a pump coupled to the housing inlet of the apparatus by a first conduit.15. Apparatus substantially as described herein with reference to the accompanying drawings.