IL32218A

IL32218A - Treatment of solids with fluids

Info

Publication number: IL32218A
Application number: IL32218A
Authority: IL
Original assignee: Welch R
Priority date: 1968-05-14
Filing date: 1969-05-13
Publication date: 1971-11-29
Also published as: ES367191A1; GB1276541A; JPS4947832B1; CH518120A; US3522659A; FR2009890A1; NL6907487A; IL32218A0; BE733026A; GB1230915A; BR6908742D0; DE1919888A1

Description

Treatment of solids with fluids RALPH ARTHUR WELCH . The present invention is concerned with a device, and method of treating solids, such as fibrous or particulate solids with fluids such as pressurized gas.

The invention makes available a family of mater al treating devices, useful in many material treating processes, wherein it is desired to agitate solid material in either particulate or fibrous form by directed streams or jets of pressurized gas or liquid.

The invention provides a device for treating material with a fluid under pressure, the device having a chamber for receiving material to be treated, the chamber being defined at least in part by outer and inner boundary surfaces of revolution about aligned axes, the outer boundary surface having a relatively large diameter first end portion and a relatively small diameter second end portion, the second portion defining a chamber outlet, the inner boundary surface being at least in part of substantially conical shape having a base portion adjacent the outer boundary first end ' portion and having an end of reduced diameter facing the chamber oitletj and at least one fluid inlet passageway, opening into the chamber at a point in the zone of the 'outer boundary first end portion and the inner boundary base portion, so that a stream of fluid admitted therethrough under pressure makes initial surface engagement with one of the boundary surfaces along a line oblique to the. boundary surface axes.

In the devices of the invention, treatment of material can be effected by placing the material in the chamber and introducing one or more defined streams or jets of pressurized ga(s or liquid into the chamber into surface engagement with orje of the boundary surfaces. It is believed that the design of the devices of the invention is such that the boundary surface with which the fluid makes initial contact functions to at least initiall guide the gas along defined paths towards the chamber outlet, while the other boundary surface /serves to restrict or control expansion of the introduced gas and to prevent or reduce the occurrence of. flow bypass areas within the receiving chamber. Depending upon the process for which the devices are to be used, the gas introduced into the receiving chamber may be either inert or reactive with the material being treated and may be at any desired operating temperature.

Preferably, the cross-sectional area of the chamber varies from minimal values adjacent the areas of the gas inlet(s) and chamber outlet(s) to a maximum value in the area of the reduced diameter end portion of the inner boundary surface. This permits maximum expansion of the pressurized gas adjacent the reduced diameter end portion of the inner boundary surface and this is believed to permit maximum surface contact of the pressurized gas with the material being treated.

In one embodiment of the present invention, one (or more) defined stream(s) of pressurized gas is introduced into the receiving chamber in initial surface engagement with the conically shaped portion of the inner boundary surface along a line oblique to the boundary surface axes.

In a second embodiment, the outer boundary surface is the surface of revolution of a line having compound curvature about the boundary surface axes, wherein the respective ends of such line are parallel to such axes and define first and second end portions of the outer boundary surface. The first end portion of the outer boundary surfa.ce is adjacent to the base portion of the conically shaped inner boundary surface and the second end portion of the outer boundary surface defines a chamber outlet. In this embodiment, one (or more) defined stream(s) or jet(s) of pressurized gas is directed into initial surface engagement with the first portion of the outer boundary surface along a line which is oblique to the boundary surface axes.

Preferably, the line along which each stream of pressurized gas is directed into engagement with the respective boundary surface also lies as nearly as possible within a plane parallel to such surface at the point of initial engagement therewith.

The devices of the invention may be used to treat material within the chamber in either a batchwise or continuous manner. When batchwise treatment is' desired, a measured quantity of material may be initially introduced into the receiving chamber and subsequently introduced jets of gas employed to treat and then eject the treated material through the chamber outlet. When a continuous material treating process is desired, the devices may be modified by providing a material inlet passageway which terminates at the reduced diameter end portion of the inner boundary surface and is aligned with the chamber outlet. Material to be treated and the pressurized gas may then be simultaneously and continuously introduced into the receiving chamber and exit through the chamber outlet.

In order to demonstrate the general utility of the present invention, several diverse material treating processes are hereinafter described. In a first process, material to be treated is in the form of a pov/dered solid and jets of inert pressurized gas employed to fluidize the powdered solid and thereafter expel the solid from the receiving chamber in a fluidized stream. This procedure is useful, for example, in the application of controlled dosages of pov/dered medicaments entrained within an inert carrier gas in the treatment of humans or animals and particularly in the treatment of bovine mastitis which occurs in dairy cattle.

In a second process, textile yarns are continuously introduced into and withdrav/n from the material receiving chamber and subjected to directed jets of pressurized gas v/hile disposed within such chamber in order to perform either mechanical yarn treatments, e.g. , entanglement or chemical yarn treatments, e.g. dyeing.

The invention will now be described in the following Examples and with reference to the accompanying drawings. In the Examples "Freon" is a Registered Trade Mark In the drawings .:- Fig. 1 is a sectional view illustrating a first embodiment of the invention Fig. 2 is a sectional view along the line 2-2 of Fig. j Fig. 3 is a fragmentary view showing flow passages provided in the embodiment illustrated in Fig. lj Fig. 4 is a sectional view illustrating a second embodiment of the invention; Fig. 5 is a side elevational view of the con-ically shaped flow guide shown in section in Fig. 4; and Fig. 6 is a fragmentary sectional view of a modification applicable to the first and second. embodiments to adapt them for continuous operation.

To facilitate understanding of the present invention, the first and second embodiments thereof, which are shown in Figs. 1-3 and Figs. 4 and 5, respectively, will be described with particular reference to their use in treating solid material in powdered or other particulate form in a batchwise manner. More particularly, reference is made to their use in applying accurately controlled dosages of powdered medicament in the treatment of bovine mastitis, where- in pressurized gas from any suitable source (not shown), is used.. to fluidize the medicament and inject it in a fluidized stream into the udder of a cow. In practice, any suitable pressurized or carrier gas such as carbon dioxide, nitrous oxide, and fluorinated or fluoro-chlor-inated saturated hydrocarbons may be employed.

Illustrative of those medicaments which may.be used in the treatment of bovine mastitis are steroids, such as prednisolone, dexamethasone , hydrocortisone, cortisone, prednisone and their derivatives, i.e. salts, esters or aldehydes thereof; nitrofurans, such as nitro-furazone; sulfur drugs, such as sulfisoxazole and sulfamer-a'zine; and antibiotics such as polymixin, bacitracin, pro-caine; pencillin G, dihydrostreptomycin , streptomycin, neomycin, tetracycline, chlortetracycline , kanamycin, novobiocin, oxy tetracycline , chloramphenicol, erythromycin and their salts and derivatives. However, any medicament effective against bovine mastitis may be used.

It is preferred, however, to use a mixture of nitrofurazone and sulfisoxazole having a particle size of from 1G to 100 microns. The amount of medicament employed will, of course, vary depending upon the severity of the disease to be treated.

Referring to Fig. 1 there is provided a device, generally designated as 1, which includes an integrally formed molded plastic body 2 having a through axially extending opening 3 which is adapted to receive a flow guide, generally designated as 4, and a nozzle or tube 5. Opening 3 is defined by a tapered wall mounting portion 6, a cylindrical wall portion 7, a second tapered wall portion 8 having a plurality of slot recesses 9, a second cylindrical wall portion 10, a third tapered wall portion 11, and a stepped nozzle supporting wall portion 12.

Device 1 may be connected to a suitable source of pressurized gas (not shown) by any suitable means such as frusto-conical mounting plug 13, which is received within opening 3 in frictional surface engagement with tapered wall mounting portion 6. Other possible coupling arrangements, will be readily apparent to the skilled engineer By referring to Fig. 1, it will be understood that plug 13 is provided with an end surface portion 14 which cooperates with projections 18 on second tapered wall portion 8 to facilitate positioning of flow guide 4, in a' manner hereinafter more completely described and a through axial bore 15 to afford flow communication between a source of pressurized gas and the interior 25 of flow guide 4.

Flow guide 4 as shown in Figs. 1 and 2 includes a cylindrical wall portion 16 having a plurality of circum-ferentially spaced, radially extending spacing projections 17 and axially extending spacing projections 18 and a conically . shaped wall portion 19 having a reduced diameter end portion 20. Guide 4 is frictionally retained within opening 3 with the cylindrical wall 16 thereof maintained in a centered spaced relationship with respect to opening cylindrical wall portion 7 by radially extending spacing projections 17. When thus positioned, the surfaces of wall portions 7 and 16 cooperate to define an annular pressurized gas flow passageway 21, and the surface of conically shaped wall portion 19 is in a parallel abutting relationship with second tapered wall jportion 8 and laterally closes slot recesses 9 provided therein. If desired, permanent positioning of flow guide 4 within opening 3 may be effected by thermal or adhesive bonding.

When the device is assembled in the manner described, there is defined a materialrreceiving chamber.22 having an outer boundary surface of revolution formed by body opening wall portions 10 and 11, and an inner boundary surface of revolution formed by the conically shaped surface 19 of flow guide 4, the axes of the respective boundary surfaces being disposed in alignment. The outer boundary surface is shown in Fig. 1 as having a first end portion of relatively large diameter, designated as A, which is adjacent the base of the conically shaped inner boundary surface, and a second end portion of relatively small diameter, designated as B, which defines the outlet for chamber 22.

Slot recesses 9, when laterally closed by the conically shaped surface of guide 4, define a plurality of passageways which are adapted to direct gas passing through flow passageway 21 in the material receiving chamber 22 as defined streams or jets of pressurized gas along flow lines oblique to the axes of the inner and outer boundary surfaces. Preferably, the- flow lines lie within planes disposed sub- stjantially parallel to the conically shaped inner boundary surface adjacent the outlet ends of recesses 9. Thus, the gas streams which initially engage that portion of flow guide 4 which defines the inner boundary surface at the outlet ends of recesses 9 tend, due to surface effects, 'to follow the contour of the conical shaped inner boundary surface along spiral-like paths v/hich eventually tend to merge into one radially defined gas stream adjacent the outlet 23 of chamber 22, It has been found that by. providing a conically shaped flow guide, wherein the cone angle is approximately 90°, in combination with gas streams or jets arranged j_n the manner described, there is obtained an unexpected increase in the fluidizing capabilities of such streams over those obtained when such streams are merely directed into chamber 22 along paths disposed obliquely of the axes of the inner and outer boundary surfaces.

While flow guide 4 is shown in Fig. 1 as being conical, it will be understood that it may be frusto-conical , as indicated in the case of the modification shown in Fig. 6 wherein the flow guide has the external overall shape of a frusto cone. In this respect, it appears that the most critical, design consideration is to provide a conical flow guide section immediately adjacent the point at which gas is introduced into chamber 22 in order to achieve a desirable initial gas flow pattern, coupled with a chamber design v/hich prfovides maximum chamber cross-sectional area and thus maximum flow expansion adjacent- the reduced diameter end portion 20.

When device 1 is mounted on mounting plug 13, axially extending projections 18 of flow guide 4 are in abutting engagement with surface 14 of plug 13 and cooperate therewith to define radially extending . passageway 24, and to positively maintain flow guide 4 in surface engagement with second tapered wall portion 8. The rearwardly facing surface of flow guide 4 is hollowed out to form a cavity 25, the sidewalls of which tend to equalize distribution of gas passing through plug aperture 15 radially through passageway 24. Thus, pressurized gas is relatively uniformly distributed in sequence to passageway 21 and recesses.9.

Material to be treated may be placed in chamber 22 prior to positioning of flow guide 4 within body opening 3. Alternatively, material may be placed in chamber 22 the after positioning of/flow guide either through tube 5 or through apertures, (not shown) provided in either plastic body 2 or flow guide.4.

Figs. 4 and 5 illustrate a second embodiment of the invention wherein the ..treating device, generally designated as 100, incorporates various possible design variations of the structure of treating unit 1. Further, in Fig. 4, dissimilar device mounting means are shown as including a fitting 13' which is provided with a threaded, cup-shaped mounting portion 13'', which additionally functions to define a pressurized gas distributing cavity 25'. Fitting 13' is further provided with a bore opening 15' to permit pressurized gas to be admitted into cavity 25', and a jforwardly facing annular surface 14'.

Treating device 100 includes an integrally formed body 101 having an integrally formed radially extending flange portion 102 and a through axially extending opening. 103 which receives a flow guide 104 and a tube or nozzle 105, Opening 103 is defined by a cylindrical wall portion 106, a radially extending shoulder defining wall portion 107, a curved wall portion 108, and a wall portion 1.09 which threadably receives tube 105.

Flow guide 104 in the form of a solid body having a conically shaped surface portion 110 which defines reduced diameter end portion 111, and a radially extending flange portion 112 which is provided with a pair of slot recesses 113 which define through flow passages between flange surfaces 114 and 115. Flow guide 104 is centered within through opening 103 by cylindrical wall portion.106 in abutting engagement with radially extending wall portion 107. When so positioned, cylindrical wall portion and radially extending wall portion 107 laterally close slot recesses 113 to define a plurality of pressurized gas directing passageways extending between guide flange surfaces 114 and 115.

Body 101 and flow .guide 104 cooperate to define a material receiving chamber 116 having an outer boundary surface of revolution formed by curved wall portion 108 and an inner boundary surface of revolution formed by the conically shaped surface 110 of flow guide 4 the axes of the respective boundary surfaces being aligned. As in the case of treating device 1, the outer boundary surface has a first end portion of relatively large diameter, designated as A, which is disposed adjacent the base of the conically shaped inner boundary surface, and a second end portion of relatively small diameter, designated as B, which defines outlet 117 of chamber 116.

The outer boundary surface formed by curved wall portion 108 is defined by revolving about the axis of body 101 a line of compound curvature having its respective ends which define the first and second end portions of the outer boundary layer, disposed parallel to the body axis. While various curved surface designs are possible, it has- been found that excellent results are obtained by revolving a compound curved line having the coordinates tabulated below, · wherein point 0 is designated as A, point 10 is designated as B and the radius is measured from the axis of body 101 to an appropriate point on the curve.

Points Radius 0 .437 1 .421 2 .406 3 .390 4 .312 .250- 6 .187 7 .125 8 .093 9 .062 .062 In the above tabulation, the distance between points is 0.125 inches and the radius is measured in inches. An inner boundary surface having utility with an outer boundary surface approximated by the above tabulation would include a cone having an angle a of 60° wherein the reduced diameter portion or apex is positioned on' the boundary surface axes radially of point 4.

Material receiving chamber 116 may be modified to accomodate either increased or decreased gas flows by multiplying both the spacing betv/een points and the radii given above by any desired common factor and employing a cone height sufficient to maintain the apex portion of the inner boundary surface at approximately point 4.

Device 100 is mounted on fitting 13* by a threaded locking ring 118, which clamps flange 102 in fluid sealing engagement with surface 14' of mounting portion 13'·.

' In operation of the second embodiment, filling of the material receiving chamber may be effected in the same manner as in the first embodiment. However, in the second embodiment, pressurized gas introduced into cavity 25' from a suitable source of pressure (not shown) is directed into material treating chamber 116 by recesses 113 into initial surface engagement with the outer boundary surface along line oblique to the boundary surface axes and lying within planes which are substantially parallel to the first end portion of the outer boundary surface at points adjacent the outlet ends of recesses 113. Thus, streams or jets of gas upon emerging from recesses 113 tend to follow or be guided by the outer boundary surface along spiral-like paths which eventually tend to merge adjacent chamber outlet 117.

Also, as in the first embodiment, the inner and outer boundary surfaces of revolution cooperate to define a material receiving chamber which functions to produce a reverse venturi effect, that is, to produce a greater flow cross-section adjacent the mid-point of the chamber, which is in the area of the reduced diameter portion 111, than adjacent the inlet and outlet ends thereof. This results in both increased gas volume and reduced gas velocity. at such mid-point. Such variable flow cross-sectional design, coupled with the gas streams directed in the' manner described produces unique gas flow patterns having excellent fluid-izing and opening capabilities.

In operation of either of devices 1 or 100, the quantity of material placed within the receiving chamber thereof determines the pressure and quantity of the gas to be admitted into the receiving chamber for the purpose of effecting complete fluidization and discharge of such material 'through the chamber outlet as a fluidized stream. When em- / ploying these devices in a process for treating bovine mastitis, the quantity of medicament placed within the treating chamber is determined by the seriousness of the infection to be treated.

EXAMPLE I A thoroughly mixed medicament consisting of 200 milligrams of nitrofurazone and 400 milligrams of sul- fisoxazole having a size average of 20 microns was introduced into the chamber 22 of device 1. Tube 5 was introduced into the udder to be treated and thereafter 20 cc of "Freon" 12 at about 70 psi was introduced into chamber 22. The medicament was found to be completely fluidized and discharged from the chamber and the medicament uniformly distributed throughout the udder. The milkout time for several like treatments was found to vary from between one and three days.

EXAMPLE II A thoroughly mixed medicament consisting of 200 milligrams of nitrofurazone,.400 milligrams of sulfisoxazole and 250 milligrams of lactose having an overall size average of about 50 microns was introduced into chamber 116 of device 100. Tube 105 was introduced into the udder to be treated and thereafter 20 cc of "Freon" 12 at about 70 psi was introduced into the chamber 116. The nned icament was found to be completely fludized and discharged from the chamber and the medicament uniformly distributed throughout the udder. The !milkout time for several like treatments was found to vary between about one and three days.

Fig. 6 illustrates how the several embodiments of the present invention and the second embodiment in particular, may be modified to permit material to be continuously introduced into material receiving chamber 116. In this modification, flow guide 104 has a through axial bore 119 in alignment with the axes of the respective boundary surfaces and having an outlet end in the zone of the reduced diameter end portion 111. A tube 120, in axial alignment with bore 119 and fixed to flange surface 114, prevents contact of the material to be treated with the pressurized gas during passage of the material through fitting cavity 25'. The device of Fig. 1 may be similarly modified by providing an axially extending bore opening in flow guide 4 and a suitable material conveying tube fixed to the flow guide and extending rearv/ardly through bore opening 15.

While the modification illustrated in Fig. 6 may, if desired, be employed to either continuously or intermittently introduce powdered or particulate solid material into receiving chamber 116 in accordance with the method pf treating bovine mastitis mentioned above, it has been found to have particular utility in the treatment of multiple filament and staple textile yarns.

For instance, multifilament yarn may be treated by the apparatus shown in Fig. 6 to produce a textured yarn having alternate thick and thin portions spaced along the length of the treated yarn bundle. To achieve such a textured yarn, a gas, such as air under pressure, may be continuously introduced into cavity .25· and multifilament yarn would be continuously fed into chamber 116 through tube 120 and withdrawn therefrom through tube 105 along a straight line path by forwarding rollers. The speed of the forwarding rollers may be intermittently adjusted to permit the rate of feed to intermittently exceed the rate of yarn withdrawal, thereby permitting the individual filaments of overfed portions of the yarn to be freely separated from each other and whipped around by the gas flow to form convolutions or loops which are thereafter retained in the yarn upon withdrawal from chamber 116. The convolutions or loops impart bulkiness to the yarn by maintaining the filaments in spaced relation.

It has also been found that the treating devices of the invention may be employed to effect the interlacing or entanglement of yarn continuously along the length thereof by continuously drawing multifilament yarn under slight tension through tube 120, chamber 116 and tube 105; introducing a first pressurized gas, such as air, continuously into cavity 25', and continuously introducing a jet of pressurized gas, such as air, into chamber 116 through a nozzle (not shown) I substan ially perpendicular to the path of yarn through the chamber at a point between reduced diameter portion 111 and outlet 117. In operation, the pressurized gas introduced into cavity 25· acts upon the filaments of the conveyed yarn I to effect opening thereof and the jet of gas introduced through ! ! the side wall of chamber 116 reorient individual filaments within the opened yarn bundle to effect relative displacement and interlacing thereof.

Alternatively, both multifilament and staple yarns may be subjected to dyeing treatment within the treating chambers defined by the devices of the present invention by continuously passing the yarns to be treated through the chamber and continuously introducing either a vaporized dyeing agent or a finely divided dyeing agent entrained within a pressurized gas into the chamber in order to effect both opening of the yarn and intimate association of the dyeing agent, with the individual yarn filaments or fibers.

Still further, the devices of the present invention may be employed to produce a wrapping on a core yarn. When used in this manner, a core yarn is continuously fed axially through the treating chamber under slight tension and a wrap, either in continuous filament or staple form, is introduced through a suitable opening in the side wall of the . chamber. Rotating movement of the core yarn caused by action of the pressurized gas jets acts to draw the wrap into the wrapping chamber and effect/thereof about the core.

Claims

■ What I Claim is: i

1.' A device for treating material with a fluid under pressure, the device having a chamber for receiving material to be treated, the chamber being defined at least in part by outer and inner boundary surfaces of revolution about aligned axes, the outer boundary surface having a relatively large diameter first end portion and a relatively small diameter second end portion, the second portion defining a chamber outlet, the inner boundary surface being at least in part of substantially conical shape having a base portion adjacent the outer boundary first end portion and having an end of reduced diameter facing the chamber outlet; and at least one fluid inlet passageway, opening into the chamber at .a point in the zone of the outer boundary first end portion and the inner boundary base portion, so that a stream of fluid admitted therethrough under pressure makes initial surface engagement with one of the boundary surfaces along a line oblique to the boundary surface axes.

2. A device as claimed in Claim 1, wherein the end of reduced diameter has an aperture through which. material to be treated can be admitted to the chamber.

3. A device as claimed in Claim 1 or 2, wherein the fluid inlet is such that fluid admitted therethrough makes initial surface engagement v/ith the outer boundary surface.

4. A device as claimed in any preceding claim wherein the outer boundary surface is the surface of revolution of a outer-^ line of compound curvature about the axis of the^boundary , the end portions of the line, which correspond to the first I being and second end portions of the boundary surface .^parallel to the outer boundary axis.

5. A device as claimed in Claim 1 or 2, wherein """" . the fluid inlet is such that fluid admitted therethrough makes initial surface engagement either v/ith the inner bound ary surface and is directed along a line within a plane substantially parallel to the inner boundary surface at the point of initial surface engagement therewith, or with the first end portion of the outer boundary surface.

6. A device as claimed in any preceding claim wherein the conical shaped part of the inner boundary surface is carried on..-.a flow guide which engages the outer boundary surface and is located so that at least a part of the con-i'cally shaped part thereof is within the volume described by the outer boundary surface and in axial alignment therewith.

7. A device according to Claim 6, wherein the flow guide and the outer boundary surface define the fluid inlet passageway.

8. A device according to Claim 6 or 7, wherein the flow guide has a through bore in axial alignment with the surface axes, passing through the reduced diameter end portion of the cone, through which bore material to be treated can be admitted to the chamber.

9. / A d evice- as claimed in Claim 7, wherein said first and second surfaces of revolution are connected by a substantially radially extending annular wall, the flow guide bejing provided with a radially extending annular flange adjacent the base of the conically shaped surface portion, the flange having a radially facing marginal surface portion engaging the outer boundary surface and axially spaced first and second side faces, the first side face engaging the radially extending annular wall, fluid inlet passageway being defined by a slot in the radially facing marginal surface and extending between the side faces thereof along a line oblique to the surface axes,

10. A device as claimed in any preceding claim wherein the passageway is such that a stream of pressurized fluid admitted therethrough makes initial surface engagement with the first end portion of the outer boundary surface.

11. A device as claimed in any of Claims 1 to 8 wherein the inner surface of revolution is flared radially outwardly, with respect to the first end portion of the outer surface of revolution, so that a frustro-conical annular outer boundary surface portion is in surface engagement with the conically shaped inner boundary portion, and the passageway is formed by a slot in the frustro-conical annular surface, and the slot being such that fluid admitted through the passageway makes initial surface engagement with the conically shaped surface portion of the inner boundary.

12. A device according to Claim 11, wherein the flow guide includes a substantially cylindrically shaped ortion adjoining the base of the conical ly shaped portion, and the outer boundary surface includes a third surface of revolution adjoining the first surface of revolution at a point radial to the flow guide cylindrical surface portion, the flow guide being centered in axial alignment with the surfaces of revolution of the outer boundary by spacers between the third surface of revolution and the flow guide cylindrical surface portion the space provided there^between allowing fluid to be fed therebetween to the slot.

13. A device according to Claim 1 substantially as described with reference to the accompanying drawings.

14. A method of treating a particulate solid with a gas or liquid under pressure -which comprises placing the solid in the chamber of a device as claimed in any preceding claim and directing a defined stream of pressurized fluid into the chamber through the inlet passageway.

15. A method as claimed in Claim 14 wherein the solid · and fluid are continuously and simultaneously passed into the chamber. A method as claimed in Claim 14 or 15 substantially described in the foregoing/Examples. For the Applicants DR. REINKCLD COliN AND PARTNERS