FR2788229A1 - Floating sump for collecting oil and water mixture for separation without air entrainment - Google Patents

Abstract

Liquid which is to be sucked from a vessel is collected in a sump (1) floating on the surface of the liquid. The height of the sump can be adjusted by varying the position of its floats (4) on their supports (5), and the height of a collar (10) on the sump. This ensures the sump remains at a level whose liquid can enter via notches (2) in its rim.

Description

The present invention relates to a floating strainer, intended to be

  mounted upstream of any separator of immiscible liquids, of different densities, in particular with extraction of the lightest liquid, and recycling in a closed circuit of the liquid

  heaviest, by aspiration of the liquid to be treated without aspiration of air.

  Thus, the invention can be applied to the separation of liquid phases consisting of hydrocarbons and water, organic phases and water, or of all immiscible liquids,

  this in various industrial fields, including the food industry.

  Various types of strainers are known which can be adapted to all devices for the separation of immiscible liquids, these strainers having the drawback of absorbing, in addition to the liquids to be separated, the ambient air charged with the surrounding bacterial flora, thus promoting the

contamination of the medium to be treated.

  Also known, from international patent application N WO 96/20772 and from French national application N 79 04196, strainers based on the

  particulate separation of suspended solids in the liquid to be treated.

  In total opposition to this state of the art, the present invention provides a strainer whose operation is based on the admission only of liquids, by the acceleration and the entrainment of the flow of surface liquids to be separated, generated by cavities. created on the circumference of the emerging part of the strainer, whose shape by width and depth are in line with the diameter of the tube, of round section in

  the present description, according to a preferred embodiment of the invention, the latter

  obviously not being limiting, and accepting any form of collector

of surface.

  To this end, the subject of the invention is a suction strainer, floating on the surface of the liquid to be treated contained in the tank or the storage tank, the suction strainer consisting of a collector immersed in the liquid to be treat, and comprising one or more notches or cutouts at its upper part, just below the level of the liquid, these notches or cutouts making it possible to feed and maintain a full level and

  constant of the submerged strainer, its lowest part being closed and sealed.

  The submerged collector consisting of a tube closed at its lower part, and comprising the abovementioned notches or cutouts, is kept immersed in the liquid to be treated by four floats in the example described, the number of floats being a function of their unit capacity of floatation in relation to the weight of the volume of liquid contained in the submerged collector, the floats being fixed to supports on which slide the respective fixing of each by means of an orifice on a watertight fixed tab and adjustable by a

clamping screw.

  The float fixing system is connected and maintained to the body of the manifold by a clamp on the diameter of the manifold, and adjustable over the height of the manifold below the level of the notches or cutouts, to allow fine adjustment of the assembly. the floating strainer just at the level of the liquid to be treated, the notches or cutouts being thus immersed for the continuous supply of the collector by the liquid to be treated without

ambient air intake.

  The liquid intake capacity to be treated by suction through the notches or

  cuts is equal to the processing capacity of the oil separator.

  A tube of appropriate size for the flow rate of the separator of immiscible liquids, plunging into the body of the strainer for the suction of the liquid to be treated by a pump by way of example, to supply the separator, not being part of the present invention,

  is shown in the sketch of the vertical section for understanding.

  The operating principle is as follows: the liquid to be treated is withdrawn by a free tube plunging into the liquid contained and permanently renewed in the submerged collector, thus authorizing an amplitude equal to the height of the collector and the

  plunging part of the suction pipe in the collector body.

  The sampling tube is connected to the oil separator to supply the latter.

  According to one embodiment of the invention, the strainer is maintained at a constant level on the surface of the liquid by at least two sealed floats whose content, lighter than water, such as air for example, adjustable in height and corresponding in thrust according to Archimedes' law, at least to the weight of the volume of the liquid displaced and

  contained in the strainer manifold.

  Liquid bodies immiscible with water present on its surface, are entrained by the aqueous flow in the body of the floating strainer and directed into the separator of non-liquid liquids.

  miscible which separates the two phases.

  The means for supplying the fluid to be treated can include means for

  pumping, taking the fluid to be treated contained in a tank or a storage tank.

  The liquid leaving the separator can be returned to the tank or the

  storage, for recycling of treated fluid, in a "closed" circuit.

  The invention will in any case be better understood with the aid of the description which follows, in

  reference to the appended schematic drawings showing, by way of example, an embodiment of this strainer to be mounted at the suction of a separator of immiscible liquids: Figure I is a vertical sectional view of a strainer d suction according to the present invention showing the detail thereof; Figure 2 is a plan view from above of the strainer, in correspondence with the

figure 1.

  The floating strainer, to be mounted upstream of a separator of immiscible liquids, of which Figures I and 2 give an overall view, comprises a manifold 1, comprising one or more notches or cutouts 2 at its upper part, its part lowest 3

being closed and waterproof.

  The submerged collector I consisting of a tube closed at its lower part 3, and comprising the aforementioned notches or cutouts 2, also comprises four floats 4 in the example described, the number of floats being a function of their unitary floating capacity in relation with the weight of the volume of liquid 7 contained in the submerged collector 1, the floats 4 being fixed to supports 5 on which slide the respective fixing lug 8 of each by means of an orifice 9 on the lug 8 fixed waterproof and adjustable through

a clamping screw 6.

  The fastening system 5 of the floats is connected and maintained to the body of the manifold I by a clamp 10 on the diameter of the manifold, and adjustable over the height of the

  collector 1 below the level of the notches or cutouts 2.

  A tube 11, not part of the present invention, is shown in Figure I for understanding. The overall operation of the floating strainer, described so far, is as follows: Depending on the material or materials with which it is made, the floating strainer undergoes a pre-adjustment of the height of the floats 4 on the fixing system 5, by the screws 6 for tightening the fixing lug 8 of the floats themselves, this assembly also being adjustable by

  the fixing collar 10 sliding in force on the outside of the body of the manifold 1.

  The strainer thus preset is immersed in the fluid to be treated, and the fine and final adjustment as a function of the density of the fluid concerned, is effected on the position of the float (s) 4, by the tightening screw (s) 6, by sliding of the latter on the support (s) 5, and by "refining" by displacement of the flotation assembly using the collar

  mounting 10 on the body of the manifold 1.

  The floating strainer is thus positioned on the surface of the fluid to be treated, in such a way that the level of this arrives exactly at the upper level of the body of the manifold 1, the notches or cutouts 2, one or more, being so

submerged.

  The surface of the notch (s) or cutouts 2 on the top of the collector body 1, have a (total) surface ensuring permanent filling of the collector body 1, according to the capacity of the separator of immiscible liquids on which is mounted upstream the strainer which is the subject of the present invention, that is to say the flow rate of the fluid to be treated, without air intake, the fluid to be treated being extracted from the body of the submerged collector I, by the plunging tube 11, not forming an integral part of the floating strainer, connected to the separator of immiscible liquids by a flexible hose as

example.

  The suction of the fluid to be treated may or may not be continuous.

  The fluid to be treated can be recycled or not, depending on the performance of the liquid separator

  immiscible, and the desired result.

  The floating strainer, previously described, and used for its loading with a separator of immiscible liquids, is applicable inter alia to: - oil / water separation in the machine tool sector - separation of hydrocarbons in the petroleum industry , - the separation of fatty substances encountered in the food industry, the separation of sea water and crude oil during the emptying of ships

tankers, etc ...

  It goes without saying that the invention is not limited to the sole embodiment of this floating strainer which has been described above, by way of example; on the contrary, it embraces all of the variant embodiments and applications respecting the same principle. Thus, one would not depart from the scope of the invention by replacing the supply of the floating strainer to be treated by pumping, as specified above, by a gravity supply or by any other forced injection system, or again by replacing the intake manifold 11 plunging into the strainer, with an integral bellows and then forming an integral part of

  the strainer, and connectable to the hydraulic circuit of the separator of immiscible liquids.

Claims (4)

  I-Floating strainer for fitting upstream a separator of immiscible liquids, characterized in that it essentially comprises a main body (1), of vertical axis, comprising at its upper part one or more notches or cutouts (2), its lowest part (3) being closed and sealed, also comprising one or more floats (4), the number of floats being a function of their unitary flotation capacity in relation to the weight of the volume of liquid (7) contained in the submerged collector (1), the float (s) (4) being fixed to one or more supports (5) on which slide a fixing lug (8) by means of an orifice (9) on the lug (8) fixed tight and adjustable by a clamping screw (6).  2-Floating strainer to equip upstream a separator of immiscible liquids according to claim 1, characterized in that the main body (1), and the float holding assembly, are connected and made integral by a collar (10) adjustable on the manifold body (1), intended to adjust the position of the floating strainer at the level of the surface of the fluid to be treated.   3- Floating strainer to equip upstream a separator of immiscible liquids according to claim 1 or 2, characterized in that the means for extracting the fluid to be treated, by a plunging tube (11) independent, or by a bellows or other tubing integral with the floating strainer, drawing from the main body (1), include pumping means, withdrawing the fluid to be treated contained in a   any tank or storage tank.   4-Floating strainer to equip upstream a separator of immiscible liquids   according to all of claims 1 to 3, characterized in that the collector (1) is   externally provided, in the present nonlimiting example, with a collar (10), which carries, at two diametrically opposite points, adjustment fixing members for the floats (4), a total of four and grouped in pairs, both floats (4) of each pair being connected by a horizontal crosspiece (1 2), provided in the middle with a fixing (13), adjustable   vertically, which connects it to the collar (10).   - Floating strainer to equip upstream a separator of immiscible liquids   according to any one of claims 1 to 4, characterized in that the one or more   notches or cutouts (2), made on the upper part of the manifold (l), have an intake surface for the fluid to be treated allowing a flow equivalent to that of the separator   immiscible liquids without admitting air to the suction.