DE2252421A1 - MIXING PROCESS AND DEVICE FOR CARRYING OUT THE PROCESS - Google Patents

Description

Albright & Wilson Limited, PO Box Fo. 3, Oldbury , Warley, Worcestershire, England

Mixing process and device for carrying out the

Procedure

The invention relates to a mixing method and a Mixing device. In particular, the Er-. Finding the rapid mixing of solids with liquids, e.g. in the production of H-P-K fertilizers.

A.US of the published Dutch patent application 69 06224 is known that when mixing potassium chloride with an HP melt for the production of a H-P-K fertilizer with a high content of K die The viscosity of the mixture increases rapidly after mixing. To get one through in a satisfactory manner Drying from the melt to produce granular fertilizer, it is necessary to mix it up as much as possible to be carried out quickly, so that the mixture can be granulated from the melt before the viscosity has a exceeds certain critical limit. The said Dutch patent application proposes a cyclone mixer apply, with the HP melt tangential

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in a vertical cylindrical container with a funnel-shaped base is injected, and a stream of potassium chloride along the axis of the container is admitted.

While the mixer described in the Dutch patent application is satisfactory to manufacture some grades of melt granulated fertilizers have been found not to work at the Production of such fertilizers works satisfactorily, which have very high contents of potash.

Efforts have been made for a long time "to produce granular fertilizers with a high potassium content based on potassium chloride from the melt, for example those with a weight ratio H: P ₂ O: K ₂ O of 15:15:21, 15:15: or yourself Attempts to make such products on an industrial scale using the mixing device described in the Dutch patent application failed because of incomplete mixing, the formation of clogs and the longer time required to turn the product to allow Miechvorrlohtungen to flow through.

The highest industrially achieved Y / erto of K “0 at a melting ratio IT: PpOf- ^of 1 · 1 v / earth represented by a ratio ΤΓ: P _n 0_: ICO of 15:15:19 using the one described in the Dutch patent application Miscliois.

The founding creates: ο a device for premixing of "liquid coiton with particulate solids, which is characterized by oin funnel-shaped

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Lower part with an essentially vertical axis, Injectors for the liquid arranged to provide a stream of liquid can introduce tangentially into the mixer and thereby there is a liquid at least in the lower part of the

61Ώ.6Γ

Make funnel-shaped lower part / insertion device for the solid, which is arranged such that a flow of the solid is substantially along the Axis of the funnel is introduced, a baffle substantially on the axis of the funnel below the introduction device for the solid is arranged, preferably at the level or below the Height of the injectors, and shaped so that the solid particles radially outward into the vortex be deflected when the device is operating and forming a mixture, and an outlet for the mixture at lower end of the funnel.

The mixer can optionally preferably have a vertical cylindrical part above the funnel. The injectors can be either or preferably several tangential feed openings in the wall of the mixer. The feed openings are preferably arranged essentially horizontally, however, can alternatively be arranged so that they have both a downward and a horizontal, imparting tangential component to the liquid flow The number and the geometric 'arrangement of the injection openings are determined by necessity dictates to form a continuous vortex covering at least substantially the entire inner wall of the lower part of the funnel.

It is believed that one of the main reasons for the

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blockages occur in all known mixers consisted in the fact that spiral currents formed in the cylindrical part of the ink and solids formed non-moistened and at intervals or insufficiently moistened '.Yand parts accumulated what was completely it leads to the formation of bridges of the material in the mix. A continuous vortex is formed in at least the funnel-shaped part of the mixer, if so fed a sufficient number of streams with a sufficient tangential velocity will

3s it was found that the optimal conditions for Mixing can be obtained when the liquid is continuous, rapidly moving Film over the entire conical surface of the 3 I.Iischer forms up at least up to the highest point which the ricocheting pesticide particles the vortex to encounter. Preferably the film is at least one inch thick at the point where the particulate matter occurs hit the vortex. Preferably, therefore, the vortex should be downwards and most preferably extending into the discharge opening]. this is easily reached when the discharge opening

The fluid is sufficiently large and the speed of movement is sufficiently high.

According to a typical embodiment, the funnel wall can form an angle of essentially 20 ° with the Form verticals, although larger or smaller angles also allow the device to work. The angle to the vertical can be, for example, as large as 80 ° or as small as 5 °, but is usually

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between 10 and 45 °. ! For a given cowardice the Tric'ater wall becomes the diameter of the \ ustra-ge opening determine the optimal! throughput of the mixer. This should preferably be at least sufficiently large to allow the total amount of the mixture to pass through the opening under the influence of gravity flows through without a substantial amount of mixture being built up in the funnel.

The optimum number and size of the feed openings to achieve a "continuous vortex depends on the viscosity and the fluid flow rate desired. It is preferred to have two feed openings, although three, four or even more could be used. The feed openings preferably have an opening that is sufficiently narrowed to the I · ^'1 üssigkeitsströme reshuffle to tangential jets. ■

Expediently, the total cross-sectional area of all feed openings is essentially smaller than that Cross-sectional area of the Iu3trageaufnahme and according to a typical embodiment is less than that Half and preferably less than 1/4 »e.g." 1/8 of this opening. The minimum cross-sectional area of each ■ The drainage opening depends on the viscosity of the Vlüssigkoit and the pressure that can be built up in the injectors to achieve the desired flow rate achieve. The feed openings can be arranged in the wall of the funnel or in an upper cylindrical part or they can be inserted through the top of the I.

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The Einspoisovorriohtung for the stat of fe l: can consist expediently of a vertical ⁷ IoUr ¹ with θ in on of ionon Undo, dn3 is arranged essentially coaxially in the Π-ffttf) and by some suitable device, like oinem Birndfördoror orlor -chnockonför— which is fed. The l'iins ^ oinovorriciitnng for the ji ^l _e statoffo is arranged in such a way that it arcngliclrb that a stream of solids falls into the funnel.

The baffle surface l: nnn aweclcmäni ^ non-vertically adjustable in such a way that its T, ago is optimally adapted ontoprocbond to the feed-in-the-windiglcoiten of 7ost? Itoffon and PlUssiglceit. :) io Prallfinoiio preferably benefits the solid particles around the funnel. :) ine 2woclonal porm of a.? rall area represents a cone, the vertex of which is directed upwards in the east of the dome falling from the dome, eg by means of a TJtange, which is usually angled along the Llisolierachee. Such a cone is preferably shaped in such a way that '-'orralodo.i v / ird that postal matter falls directly through the opening on the lower part of the funnel. This is corrected if the maximum diameter of the cone is greater than the diameter of the outlet opening, or if the cone is wide enough to catch the London air and in oinor- nol foils inside. Uutorbalb the] '] inspei3oöf.fnung for the D'eststofΓα is arranged that the falling ι Voststoffe have a sufficient kinetlscho Tinoi.'gie ingoiionirion that they are deflected on the i'richtarwand. If necessary, the cone can be vibrated in order to prevent or inhibit the accumulation of a pesticide deposit.

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Preferably "facilities are provided that prevent clnss the 17? .itssiglceit on the impact surface. /j.Β. a protection can be installed above and outside the cone be provided edging. According to a typical concept » the form of management can be spread outwards, in such a way that the protective enclosure "and the cone go together form an outwardly directed passage through which the solid material hits the judge wall «,

An alternative: the shape of a baffle, which can sometimes be preferred to a static or vibrating cone, is a rotatable centrifugal plate. In a typical ":""naf exercise, this is a horizontal" angle, usually, though not necessarily, circular, which can be rotated with the aid of a suitable rotor about some parts located in the. Ichse the deleted device is. the plate threatens sufficiently quickly to all "Joilchen that o ^f their ergriffe"! against the Irichterwand by Sentrifu'T 1 learned to row oars. The plate can be rotated in the same "lic '^' jung odor preferably in the opposite direction to the '.7IrIjO ¹ · - ·. Ih" .o sio-τ rotating ^r; cV.Ieudnrvorrichtung l: ^r : t de :: Tortnil, r> B Rio dasu contributes to a uniform radial 7e :: toi "'ir :." the rebounding rope echo "protrudes - ""■ rin: .-: eT.

'"■ π · ..". ■: ■? Co rrof' ^. '^. E "!, rl ^ a the electrostatic charge the" pests with ^TT with the help of a highly charged tip opens up by the grounded metal body dos

IrJCh "" - ¹ * ^{5 is} isolated, a particularly effective form of lead or ricochet action, which is a particularly preferred embodiment of the invention.

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The principle of electrostatic deflection has of course been used in separators to remove pesticides introduced in streams of guests and in the Dispensing and application of paints and powder coatings applied. However, it is believed that the application according to the invention represents the first proposal, this method for the awakening of the mixing to use a pesticide with a liquid. According to this embodiment of the invention, a linear conductor, such as a wire, which is insulated from the rest of the device and essentially longitudinally the axis of a protective mantle, which is in, one typical embodiment is cylindrical, and arranged below the feed opening for the solids is charged to a voltage high enough that a peak on-load charge compared to the grounded Protective coat is produced. The stream of falling pesticides is preferably in a freely falling annular shape Curtain that surrounds the linear conductor, e.g. by means of a cone that extends above the Conductor and is arranged below or within a concentric feed tube. The particles become electrostatically charged, and many will after outside on don 7 / irbel from the melt *, the inside the earthed hopper wall flows, repelled. The charged particles repel each other, whereby Thorough dispersion ensures that what eats the wetting speed of the particulate Increased solids and iodine agglomeration tendency Solid particles inhibited. A particularly beneficial effect that has been observed is that the finer particles cause a further deflection from their downward path than the coarser ones

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! Particles are brought. This also increases the lienotsun ^ egoschwindiglceit of temporarily educated flowing "islands" from the particulate! solid.

.Gemäß a v / Eiteren / Uisführungsform the invention there is provided a method of mixing particulate Peststoffen and Plüssigteiten, which is characterized in that a liquid is / shaped irbel kontinuie to a ¹ ^, a current of Peststoffes substantially along the axis of the The vortex is dropped and the pesticide deflected outwardly into the vortex, preferably from a location at or below the level at which the continuous vortex is formed.

Preferably, the liquid becomes a continuous, rapidly rotating PiIm over the entire area at least the lower part of a funnel-shaped surface is formed with the vortex extending downwards extends up to an outlet channel on "the underside of the funnel or preferably into this.

The liquid is preferably a melt of nitrogen- and phosphorous-containing substances (ϊΤ, Ρ-melt), and the pesticide is potassium chloride. The ΙΤ, Ρ melt can be produced in the usual way, which is described, for example, in the above-mentioned Dutch patent application. G _e Mäss a typical embodiment, a mixture of ammonium nitrate and phosphoric acid ITaß-treated at boiling point with kmmoniakgas until it reaches a pH of 2.7 to 3.0 (screened eat in 10biger V7äßriger solution). The I / 'dsuhg is then evaporated to a level of 0.3 to 1.0 $, and

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the melt is fed into the mixer at an appropriately elevated temperature and pII-Y / ert. The potassium chloride is preferably vorerwrrnit and the Torrichtung including ^T! Inspei3eöffnu! I ;; en FTTR the i'lüsoigkeit and sparsely post material and the funnel can soin surrounded by a Dampfheismantel, keep the mixture fluid enough zn.

According to a particularly precautionary form of implementation the invention provides a method for mixing particulate pesticides and liquids, which is characterized by the liquidity is formed into a substantially continuous vortex, a Spitsenson charge in the ITLIhο des Y / irbels caused a current of the solids to be passed through the tip discharge, causing the plague Is electrostatically charged and the ^ solids flow into a dispersed / oil of electrostatic charged particles are transformed and the particle cloud is guided into the vortex.

The device according to the invention is described below described on the basis of the drawings. 3s show

Pig. 1 a cut through a Porm nines mixer according to the invention and

Pig. 2 and Pig. 3 schematic sections of filtering forms of impact surfaces.

The device according to Pig. 1 comprises a cylindrical one Mixing chamber 1 with a 30 cm (1Π ") high funnel-shaped Lower part 2, which is in a Y / inch of

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20 a ir-? Perpendiculars with an upper diameter of 33 cm (13 ") down onto a vertical exit pipe Tapered 3 "by 10 cm (4") diameter · The Ilischer is provided with 2 diametrically opposed tangential feed openings 4, which ge ^ reils a diameter 3/4 "(19 minutes), only one of which is shown. A vertically axially disposed inlet tube 5 provides access to the interior of the chamber 1 through the top of the "Hischers. The top of the Mixer is provided with an inlet 6 for ITsseowater. A conical baffle 7 extends sieve coaxially within the funnel-shaped rope 2 of the hischer and below the level of the feed openings 4 by means of a rod "which is coaxial within the coaxial Inlet pipe 5 is arranged. The »rod °. can sliding can be adjusted so that the baffle 7 can be raised or lowered. Sine edging or apron Above the conical baffle 7 surrounds the coaxial inlet pipe 5. The lower part of the skirt 9 is outward bent so that the skirt 9 and the impact surface 7 together point outwards and inwards Form an annular passage.

^T line \ lternative to the conical baffle 7 is a lengthy. 2 and comprises a circular horizontal impact plate 10 which is attached to the lower end of a vertical rotatable "IYeIIe 11, which lies coaxially within the coaxial inlet tube 5 and can be threatened by means of a solderer 12.

"line another alternative." .. embodiment, which is explained in 3Pig. 3, comprises a thin electrically conductive *! Dr ^ .ht ■ "?, which is arranged along the axis of the coaxial skirt 9. The upper 'ieil dos wire 13 is in

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an insulating jacket or an insulating rod 14 enclosed, made of a material such as polytetrafluoroethylene or silicone rubber, which withstands the working temperatures. The insulating jacket lies coaxially within a tubular ileal cavity 15, with the aid of which a conical flow regulator 16 below or within the coaxial inlet pipe 5 and is arranged above the lower non-insulated part of the wire 13. The wire 13 is on top End with a high voltage electrical source 17 connected and can optionally be closed at the lower end by a small ball of insulating material 13.

If the mixer is working according to FIG. 1, a Liquid, like a !!, P melt, into the mixing chamber through the tangential inlet openings 4 with sufficient Speed that a continuous vortex is formed in the hopper 2, fed. A stream of solids is allowed to fall into the mixing chamber 1 through the coaxial inlet pipe 5 and, when he meets the impact surface 7, deflected outward into the vortex in the funnel 2. The whirling mixture out Liquid and contaminant are discharged from the mixer through the outlet pipe 3.

In the embodiment according to FIG. 2, the falling stream of solids is gripped by the baffle plate 10, soft is rotated sufficiently quickly by means of the motor 12 that the solid particles through to the outside into the vortex Centrifugal forces are thrown.

According to the embodiment of Fig. 3, the falling stream of particulate matter becomes an annular curtain passed around the wire 13 through the cone 16.

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The `` isher '' that contains the apron 9 is earthed, and the wire 13 is charged to a high electric voltage to generate a peak discharge. the falling particles take on an electrostatic charge and are repelled outwards, like a disper- yawed cloud, into the vortex in funnel 2.

The invention is further illustrated by the following example explained.

example

There was a 93 to 95 $ strength Lösun'g of ammonium nitrate with cold phosphoric acid with a content of 49 to 53 y Pp ⁰ '"" ^ ^{1 s} ^ ^nem mixed ratio such that the final product has a weight ratio H: -from PPO, Had 1: 1. The mixture was treated with gaseous ammonia in a neutralizing vessel at boiling point and atmospheric pressure until a j & uivalenty. ^e: ^ Bl ~ V _i rert from 2.7 to 3.0 erielcht. A little concentrated sulfuric acid was added to increase the temperature and to prevent the crystallization of honoammonium phosphate. The 1T, P solution, which contained 4 to 8% water, was evaporated at 0.1 to 0.15 ata pressure, whereby a melt was formed which contained 0.3 to 1.0% v / water. The pII value was then increased with ammonia.

The hot melt from 170 to 180 ⁰ O was in Pig. 1 introduced through the tangential feed openings 4 in an amount of 8 m per hour mixer. "It was ground preheated potassium chloride into the mixer through the coaxial

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Feed pipe 5 in a Lie η ge of 7.4 t per hour initiated. The mixed ΙΤ, Ρ, Κ-Schmelse was direct through the / luslaßrohr 3 in a circumferential perforated Schinelztrockenföräerer at the top of a melt drying tower brought in. The hot melt-dried grains were obtained by raking from the bottom of the tower, sifted and cooled.

The process worked satisfactorily in producing a flawless high quality scumels dried granular product having an IT: P ₂ 0 _r : K ₂ O ratio of 15: 15: 21. *

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ORIGINAL

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Claims (20)

Pat en tan spray borrowed Method of mixing particulate Solids and liquids, characterized that a liquid is formed into a continuous, funnel-shaped vortex, a stream of a particulate solid fall along the axis of the vortex and the solid particles outwards into the eddy at a level below the level at which the continuous eddy is formed, to be distracted. 2. Yerfahren according to claim 1, characterized in that the vortex is formed in that a rotating IiIm of the liquid over substantially the entire area of at least the lower portion a funnel-shaped inner surface is generated. 3 Yerfahren according to claim 2, characterized in that that the vortex is down to an outlet channel on the lower part of the funnel-shaped surface or extends into it. 4. The method according to any one of claims 2 or 3, characterized characterized in that the vortex is formed in that at least one tangential nozzle jet the liquid is directed onto the funnel-shaped surface. 5. Embodiment of the method for mixing particulate solids and liquids according to one of claims 1 to 4, characterized in that the liquid in a substantially continuous V / eddy is formed, a peak discharge 09818/1088 "" ORIGINAL BATHROOM - near the vortex is generated, a stream of Solid particles passed through the tip discharge and thereby electrostatically charged the particles become, the stream in a dispersed particle cloud is transformed, and the particle cloud into the vortex is initiated. 6. The method according to any one of claims 1 to 5 »thereby characterized in that the liquid is a melt of nitrogen and phosphorus fertilizers and the solid is potassium chloride. 7. The method according to claim 6, characterized in that the mixture is then poured into a Schmelzgetrooknetes granular product is molded. 8. Apparatus for carrying out the method for mixing liquids and particulates Solids according to one of Claims 1 to 7, characterized by a funnel-shaped lower part (2) with an essentially vertical axis, injection devices (4) arranged in such a way that a liquid flow is introduced tangentially through this into the mixer and daduroh a continuous one Vortex is formed in at least the lower part of the funnel-shaped lower part /, one Inlet device (5) for the solid, which is arranged in such a way that a flow of solid particles is introduced into the mixture and substantially along the axis of the mixer, a baffle (7), which is essentially on the axis of the funnel below the introduction device (5) is arranged for the solid and is shaped so - 17 309818/1068 that the solid particles are deflected radially outward into the vortex when the device is operating, and form a mixture, and an outlet (3) for the mixture at the lower end of the funnel. 9. Apparatus according to claim 8, characterized in that the baffle surface (7) is not higher than the exit height of the injection device (4) for the liquid is arranged. 10. Device according to one of claims 8 or 9, characterized characterized in that the device for the liquid injection (4) consists of at least two there is tangentially arranged inlet openings. 11. The device according to claim 10, characterized in that the total cross-sectional area of the inlet openings (4) is less than half the cross-sectional area of the outlet opening (3). 12. Device according to one of claims 8 to 11, characterized characterized in that the height of the impact surface (7) is ■ adjustable. 13. Device according to one of claims 8 to 12, characterized characterized in that the baffle (7) has the shape of a cone which is directed with the tip upwards and is disposed substantially coaxially within the mixer. 14. Apparatus according to claim 13, characterized in that that the diameter of the cone (7) is at least as large as that of the outlet opening (3). - 18 - 309818/1068 15. Device according to one of claims 8 to 12, characterized characterized in that the baffle is a rotatable Baffle plate (10) is. 16. Device according to one of claims 8 to 15 »thereby characterized in that it additionally has a skirt (9) which is above and substantially coaxial is arranged around the baffle (?, 1ÖJ, um to protect the baffles (% 10) from splashes. 17. Device according to one of claims 8 to 12, characterized characterized in that the baffle represents an electrode for tip discharges (13). 18. The device according to claim 17, characterized in that the baffle consists of a substantially linear Conductor (13), which lies essentially in the axis of the mixer and is isolated from the mixer, a grounded protective sheath (15), which is essentially coaxial surrounds at least part of the conductor (13), and means (17) for sufficient charging of the conductor (13) is composed to form a peak discharge. 19. Device according to one of claims 17 or 18, characterized characterized in that above the electrode (13) for peak discharges and below the feed opening (5) a conical deflector surface (16) is arranged for the pesticides through which the falling Particles of pesticides around a circular curtain the electrode (13) and formed within the skirt (9) will. - 19 - 309818/1068 20. Device according to one of claims 8 to '19 _5, characterized in that the mixer on the. The tip of a melt drying tower is arranged and the output opening (3). is aimed directly at a rotatable, perforated melt dryer conveyor at the top of the tower. 303818/1068