DE2035883A1 - Process for solidifying molten sulfur and apparatus for carrying out this process - Google Patents

Description

PATENT LAWYERS

dr. W. Schalk dipl.-ing. P.Wirth dipl.-ing. G. Dannenberg

DR.V. SCHMIED-KOWARZIK DR. P. WEINHOLD DR. D. GUDEL

6 FRANKFURT AM MAIN

O*. EiCKiNHIlMtH STRAITI »·

Pff / Z July 17, 1970

Ernest Ralph ElIithorps 267-43rd Avenue, H.W. Calgary 47, Alberta, Canada, and

Ronald Bruce Fletcher 24 Rosery Plaoe, M. ¥. Calgary 41, Alberta, Canada

Process, molten sulfur »to solidify to bring and device for carrying out this procedure

The invention relates, generally speaking, to. a method and apparatus for solidifying molten sulfur. In general terms, the invention relates to conveying molten sulfur on the generally overhead surface of a movable member, cooling and solidifying the molten sulfur on that surface, and removing formations of predetermined size of solidified or partially solidified sulfur from the movable member.

Usually, elemental sulfur is first obtained in molten form by the Frasch process and by treating sulphurous acid obtained in conjunction with natural Gases and industrial gases occurs. The sulfur obtained, for example, by the Frasch process in mining is located in a liquid state and must solidify for shipping to be brought. Numerous procedures have already been

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beaten to rapidly solidify molten sulfur and then treat and transport the sulfur in a safe and efficient manner. However, none of the previously known methods has proven completely satisfactory. Rather, some of the methods currently in use to remove and store the molten sulfur, and the heretofore common method of storing and then recovering the sulfur for use, are highly impractical and inefficient. These methods are in need of improvement for the reason that they do not meet the general standards of today's technology in the field. Certain well-known methods of storing and recovering sulfur are actually somewhat ancient in their nature and undoubtedly require improvement. " For example, one widely used process for cooling and storing it is pouring the molten sulfur into rectangular molds that are approximately 45-7 cm high; In these molds the sulfur is then allowed to cool and solidify. The mold is lifted into it and the process is repeated until a large, solid block is obtained, often about 30 ^ 5 χ 150 m in size. If the sulfur is now to be brought onto the market, must it be taken out of the large boulder-like structure in which it is enclosed _? regained v / earth. The reclamation process usually requires a variety of operations, namely drilling, blasting, cracking or ripping, dozing, and smashing, to produce manageable structures, e.g., about three to four inches long and wide and with transportation requirements and sales correspond

This method has many serious drawbacks in its practical implementation. It is dangerous in erster.Linie · v / ecause the Operatin _t: spersonen hot molten. Must handle sulfur in the stage of formation and solidification «Since sulfur is a poor conductor of heat and an excellent

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The heat insulator is usually formed in the So-called vat or pile of molten sulfur "hot pockets", and these pockets or structures of molten sulfur remain as a result of the death Thermal insulation through the sulfur for an infinite amount of time, so to speak in your sulfur block. These hot bags make a big one Hazard to manual operators during the recovery process, and it is known that consequently accidents occur frequently. In addition, it should be noted that - even if the usual blasting with explosives It is quite dangerous - the use of dynamite to blow it up from blocks of accumulated sulfur the degree of danger still increased significantly. ', Tenn e.g. during the explosion A sufficient density of the sulfur particles is produced and the poor at the same time developed in a critical way !,! tightness or density occurs, this can result in dangerous fires or even more explosions occur. The breaking open and smashing of the Schv / ef el blocke s that with the present The recovery process used is typical, leaves a large amounts of sulfur dust are produced, which often cause dangerous, lightning-like fires. There is also the Sulfur dust consists of very small particles with a low specific weight, which often results in abrasion and rinds Abrasion particles leads at low speed, which thus brings about the disadvantage of air pollution.

It has also been known for many years that sulfur on tapes made of stainless. Steel can be hardened, which has a system of spray nozzles that spread out over about 92.5

extends up to 123 m, with speeds from 12.5 to 30.5 and run 6.2 m / minute. This process has proven useful for the production of sulfur flakes for the sulfur industry proven useful. 2s has been shown, however, that this method is extremely costly compared to the other method in which. in tubs or molds "Blocks made and then blown up. And smashed

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be to the sulfur in the manner described above to regain.

Compared with the known method can si oh the inventive method and the apparatus for carrying it out at comparatively low cost and with a high degree of security to perform so that it can be introduced readily than oe ~ friedigende solution of Hauptscnwierigiceiten and tasks during the solidification process and in the recovery of the sulfur occur.

The invention therefore aims to address the significant issues involved in the storage and recovery of sulfur today To remedy deficiencies and to create a method and a device through which one can sulfur with good. Efficiency and high security can freeze and store.

In accordance with the general principles of the invention, a method of solidifying molten sulfur and an apparatus for carrying out the method are provided. which convey a layer of molten sulfur on the usually overhead surface of a movable member, the surface of which is designed to prevent the hardened or partially solidified sulfur from adhering to the surface during its cooling and solidification. The actual cooling of the sulphate can be advantageously effected in that the surface BEZW "the bearing 5 ¹ Iaehe of the movable member of its Langserstreciomg is tilted at certain selected locations so that the molten sulfur approximately in the range of these selected Steep in the transverse direction from the one side the load-bearing surface flows off to the other. This transverse transport of the sulfur tends to cause the molten sulfur to roll and to expose a considerable part of the mass of the sulfur to direct contact with the air.

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Instead of depnori, the sulfur can cool down and solidify advantageously by being effected by the fact that the scirulfur layer several times immersed in a bath or series of baths of aqueous coolant arranged along the supporting surface of the movable member dips successively. On top of the initial sulfur layer, a further sulfur layer or several sulfur layers can be added applied to form a lamellar layer or layer of solidified sulfur; in this In the case, however, the initial sulfur layer must be sufficiently thick and be strong to support the subsequently applied layer or layers.

Below are preferred embodiments of the invention, for example, with reference to the drawings, namely shows g t

.Fig. 1 schematically shows the overall arrangement and structure an embodiment of the invention, the for tilting a belt in the transverse direction is used;

2a and 2b in the same way-the-movable and tilted one Band of the embodiment according to Fig 1 j '

Fig. 5 schematically shows a representation of the method and the device according to the invention, the BEZW. which works with successive immersions of the sulfur?

Fig. 4 is a close-up view of an embodiment ciOrm with one to cool the molten. Sulfur serving Sreppej

Fig..5 a snapshot representation of a as Damm and / or serving execution over which the molten sulfur can flow.

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Fig. 1 shows a ladder-shaped cooling system for sulfur, which is designated as a whole with 10 and which is designed so that it contains the pesohinoIzenen sulfur of 2ufu.hr-

/ en "S"
or discharge line from known devices

. takes. It can be seen that the cooling staircase 10 with Exhaust ducts are provided at each step of the staircase, which serve as' i heat outlets. Its additional cooling the molten sulfur can be effected in this stage of the process according to the invention by that you have cooling air in the desired amount on the melted sulfur inflates. The molten sulfur then flows off the cooling stairs by its own weight 10 into a receptacle 12. A sulfur pump 13 is arranged to pump the molten sulfur through line 14. The molten sulfur can by means of a dispensing valve 15 or 15 a to a weir-like overflow device 16bezw. 16 a submitted are .. The overflow devices 16 and 16 a are like that formed that gie absorbed a given volume of sulfur and the liquid sulfur on the upper

'area of a movable or Release drivable belt, which is attached under the outlet of the overflow device, to be released when the volume of sulfur contained in the overflow device has reached a predetermined level. A water bath 18 is fed by a vifasserzufuhrquelle, and, _ water can be conveyed by means of a pump 19 through a conduit 20 into a .Tasserkühler 21 and circulated. The sensed water can then be conveyed through a further line 22 to a humidifying device 23 which is attached above the surface of the driven ball 17. In this way, a film of water can very easily be applied to the surface of the belt "The higher one". and / or raised parts 24, 25, 26, 27 and 28 of the moving belt 17 are intended to convey the IGLppabsohnitte of the belt 17 provided at a distance from one another.

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which serve to allow the molten sulfur to flow across the belt in the transverse direction - alternately in the opposite direction, while it otherwise flows in the longitudinal direction on the sand 17. The system shown in Fig. 1 provides 2 separate conveying devices for the supply of molten sulfur via overflow devices 16 and 16 a. These separate conveying devices make it possible to apply a second layer of molten sulfur to the first sulfur rail, overlapping it, and to form a film-like, or laminated, leaf-like pattern on this. To produce sulfur. If desired, ν / more sulfur layers can of course be applied. ¹ Fig. 1 shows a centrifugal device 29 »which consists of a conveyor belt rotating at high speed, which, when it has solidified on the belt 17, moves the sulfur over distances of ζ ν B. 22.8 to 30.4 m Able to throw sulfur stacks. At this point the sulfur is still in a state generally referred to as the "green" state, and in this state the breaking of the solidified sulfur is reduced to an absolute minimum.

2a and 2b show an example of how the movable belt 17 can be tilted to ensure that the molten sulfur flows alternately in opposite directions. In Fig. 2b, the bottom left figure denotes a section along the line A - A and the right figure along the line 3 - B, Figure 2a, viewed in the direction of the arrow. Supporting structures not shown in the drawing are used to lift the belt and / or to tilt at the desired angle and are designed accordingly. It is of course desirable that - when the sulfur cools and

_{> (} solidifies to a greater extent, the tendency at

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Zipping can be chosen to be steeper or steeper adjustable in order to achieve the best degree of cooling effect. Of course, the tipping sections 26, 27, 28 of Fig 17 from 15.5 to 20 _seconds 4 cm. Figures 2a and 2b illustrate angles of inclination, or angles of inclination, which may be considered practical in causing the molten sulfur to flow transversely on the belt.

In another embodiment according to FIG. 3. 3, the molten sulfur, while being moved in the longitudinal direction of the belt 17, is subjected to successive immersions in baths 30 containing an aqueous coolant, for example water. A flaky or lamellar layer of sulfur can be produced by using suitable sulfur supply devices such as those described in Ii ¹ Ig. 3 are only shown schematically at 51, additional layers of molten sulfur are applied nine pump 32 is set up to convey water through a line 33 to a water sensor 34, which can be stranded with a blower or fan 35, which supports the oiling of the water . The cooled water is then returned to the wet bath 37 through a line 36 for reuse. Cutters 38 for sizing the sulfur chunks are according to Pig. 3 provided in order to cut up the solidified or partially solidified sulfur to Schwefelgebilden.reiner predetermined size. The cut ones

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Pieces of sulfur are then thrown by the spinner onto a sulfur supply pile, which is usually located near the end of the entire device. During operation and in practice, it has been found that the sulfur is advantageously fed onto the cooling staircase 10 in order to cool it temporarily before it is subjected to the solidification process on the belt 17, while the sulfur undergoes its own weight through the stages Eühltreppe 10 flows down and is finally released into the container 12, there is a rapid release of heat. If the molten sulfur is still too hot at this point in time at which the molten sulfur reaches the container 12, the sulfur can be passed to and over the cooling staircase 1o for a second pass before it is subjected to the solidification treatment. One can and will opt for the recycling of sulfur when the latter for the supply in. The container 12, for example a temperature of MENR than about 130 has ⁰ C. The molten sulfur should advantageously be cooled down as much as possible before it is transferred to the belt 17. If a greater amount of heat is extracted from the sulfur before it reaches the strip 17, it is easier to treat and to solidify. Therefore, as much heat as possible should be extracted from the sulfur before it is transferred to the belt. The molten sulfur is usually treated further; with an output starting from 118. Pur die ^{: <} Zwacke the practical implementation can according to]? Ig. 3 a tape made of stainless steel or similar plastic material can be used; however, it is necessary for the embodiment according to FIG. 1 that the band be made of a more flexible material, for example tough and heat-resistant rubber. It is clear that the one for the tape after i'ig. Must be 1 V / ork ~ used material the Eigeri3shaft have, in the iüaße to be flexible, that is sculptured or inclined set portions of the belt as they are formed in Fig. 2a and 2 are shown b skill to the '.- 'ju er to induce movement of the molten sulfur on the belt. "■

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It has been found that satisfactory results are obtained for carrying out the invention if an average of 10 to 11 t / hour is processed at a belt speed of 19 »dm / s. Experiments were run at this rate for approximately 164 hours and there was virtually no loss of sulfur. The treatment time from the start of the supply of sulfur to the recovery of the solid shaped sulfur pieces was about 1.5 _s l.iinuten the length of the tapes 17 according to the invention was approximately 50.4 π and the width was about 91 cm. It has been found that it is expedient to use 3 »8 l / minute of water and that, with a regulated supply, a water film about 0.4 mm thick or less is produced on the surface of the moving belt. '''

In i'ig. 1 it can be seen that the valves 15 and 15a are set so that they allow an inflow of sulfur to the overflow devices 16 and 16a in such a way that they remain filled to the desired overflow level The "excess of molten sulfur flows over the hand of the Überlaufw.ehree 16 resp. 16 a and flows as an evenly thin film of molten sulfur onto the moving belt 17 arranged below Makes formation of a pile of the desired thickness possible. The layer formation by lamination of the sulfur is not absolutely necessary according to the invention. It has been found that satisfactory cooling can be achieved with the method shown in FIG. 1, in which a cross flow of the sulfur is brought about ; however, if it is desired to form the laminated layers, precautions must be taken release molten sulfur onto the belt in a variety of films. In the embodiment according to tfigo 1 köanoa i% 3 »two separate layer films are advantageously released onto the belt by the sulfur stream coming from the valves 15 and 15 a through the overflow devices 16 and 16 a

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adjusts or regulates accordingly. In the same way one in the embodiment according to J? ig. 3 the sulfur stream the delivery points 31, which are distributed over the length of the moving belt 17, regulated accordingly as desired.

If the molten sulfur is conveyed on the belt 17 and formed into a plurality of overlapping separate layers and if the length is allowed to go between the application point of each of the layers to the next and to the end of the belt, it results that a larger part of the sulfur solidifies to an amorphous state. It is also to be assumed that the shrinkage of the sulfur occurring in the longitudinal direction of the strip 17 contributes to detaching the solidified sulfur from the surface of the strip. However, if a thin film of water or other aqueous coolant is applied to the tape and the Jig. 1 applied to generate cross-currents of the sulfur, the water film prevents any noteworthy adhesion of the solidified sulfur to the strip 17. In addition, the shrinkage of the solidified sulfur helps to detach the solidified sulfur from the strip. ä ^r hen a laminated layer of sulfur is to be formed, the valves 15 and 15 a suitably adjusted so that they s.uf layers, each approximately 3 mm generate the moving belt 17, one viendet the method according to Pig. 3 to immerse the sulfur in successive cooling baths, each of the layers is cooled by immersion in one of the baths 30 before the next layer is applied in an overlap on the previous layer. In this way a lamellar strand of solidified sulfur can be produced in a dide of about 9.5 m. It is preferable to ensure that the belt 17 is always moistened in an "appropriate" ./eise with a thin film of "./water or other aqueous agent." A tape could be caused if it was made of rubber or a similar material, thereby causing adhesion between the sulfur and the rubber

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and prevent the tape from being satisfactorily freed from the sulfur »

Since the solidified sulfur has very high thermal insulation properties during the layer formation ₉ the first layer of solidified sulfur, e.g. 3 mm thick, prevents a large amount of Yfärin coming from the subsequent layers from entering the band 17 and damaging it The treasure created in the first layer eliminates the aforementioned difficulties of weighing everything between the sulfur and the belt "However, this problem is not to be regarded as essential in the embodiment according to FIG. 1 with cross-flow of the sulfur." a considerable part of this material is quickly exposed to contact with the air, so that the heat of the sulfur is released more quickly to the outside and, as a result, there is practically no substantial heating of the strip »

When the sulfur has solidified, it can undergo a cutting process be subjected to, ζ «.Β- by means of the Schneid-Vorrientong. J8> by which the size dimension of these pieces of sulfur is made at this stage of the process is the sulfur in amorphous state. 3s there is practically no ICrystal lisation before, and during the cutting process a noticeable narrow of dust or fine particles arise has a considerable temperature at this stage of the process, but is in a stage of solidification »see above that he is responsible for cutting off and removing the sulfur pieces, z.3 »by the spinner 29 to a near · = located stock pile is suitable »In Figo 3 it can be seen that the cut sulfur pieces on a rising Section '39 of the belt 17 migrate upwards so that any excess of '.Yasser can drain off' for additional Drying is a fan 35 immediately above the rising Section of the belt 17 baked in order to remove the remaining moisture from the sulfur ο, ", .. ,, ..

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M ± e has already been mentioned above, the water supplied from the bath 37 can be pumped continuously through a cooler 34 in order to dissipate the heat that the cooling water has absorbed from the sulfur. It can be seen that the cooler 34 and the fan 35 can serve the dual purpose of removing this heat from the cooling water and also of drying the product in the manner indicated.

The size of the sulfur rate is determined in the invention by the width of the band. Generally speaking, it appears that a tape having a width of 122 cm a capacity of about 20.2 t / hour has for molten sulfur at temperatures von122 ° C to 160 ⁰ O. The need for water or other coolant would be what would be necessary to prevent normal evaporation.

In some systems, "the method and apparatus can be operated according to the invention in an environment Vierden which is open to the atmosphere, is not protected from the wind, for example, ^ eim suitable ratios are present, this operation may be advantageous to facilitate the cooling of the sulfur, For example, if a cool V / ind is blowing at a low speed. If, however, the system is operated in direct exposure to hot sunlight, there is a clearly inhibiting effect on the cooling process of the sulfur, and the process is and is less efficient more costly, in some cases it is therefore considered advantageous to enclose the device shown in Figures 1 and 3 in a housing or house which protects the device from the elements of the external atmosphere so that the device operates in a controlled environment The housing can also be designed so that there is space for the operator on the side of the housing onen of the system.

Correct the method and apparatus of the invention ic / ie economic ti many disadvantages and dangers of be ~

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knew plants for sulfur treatment and deliver for them a method and an apparatus which are industrially general can be used with advantage.

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Claims (16)

/ l £ 17th July 1970 godparents, tan sayings PW / ki / Z- 1. Procedure for solidifying molten sulfur, characterized in that. a) a layer of melted ice on a movable conveyor member (17) is conveyed, the surface of which is designed or coated, that it prevents the solidified sulfur from adhering firmly to it; . b) that a cooling bath made of an aqueous coolant this surface produced v / irdj c) that the molten sulfur through the Sihlmedium ■ the cooling bath is passed through, whereby the cooling * of the sulfur is accelerated and this is converted into a solid state "and d) that the cooled or partially cooled sulfur removed from the supporting surface of the conveyor link will. 2. Method of solidifying molten sulfur in particular according to claim 1, characterized in that, that a) a layer of molten sulfur on top of one movable conveyor member (17), preferably without its stages b and c, is required, its Surface is designed or coated in such a way that they solidified a firm clinging of the | Sulfur prevented her; b) the surface of the movable conveyor link selected places distributed over its length is tilted or pivoted in such a way that the layer located on the surface of molten Sulfur flows across the face from one side of the surface to the other; c) that the chilled sulfur is carried away on this surface. 3. The method according to claim 1, characterized in that a series of cooling baths (30) containing aqueous coolant 109823/1629 035883 included, atif the surface of the moving conveyor belt ^ are formed and a layer of molten sulfur is successively immersed in the cooling bath (30), will. 4. The method according to claim 1 or 3 »characterized in that the molten layer by passage is cooled by a cooling bath (30) to the extent that it is sufficient is solid in order to be able to carry a second layer of molten sulfur on 'its surface and that after P this cooling at least one additional layer of molten sulfur essentially, overlapping on the first layer applied and then Cools the door to form a solid laminated layer of sulfur layers results in » 5. The method according to any one of claims 1 - 4 »characterized in that that on the normally overhead surface of the movable conveyor member (17) a thin Film of water is formed sufficient to firmly adhere the molten sulfur to the conveying member to prevent. 6. The method according to any one of claims 1 - 5? characterized, that the molten sulfur is first subjected to a preliminary cooling by being placed on a Cooling staircase (10) is applied and it by its weight flows down the cooling stairs before a layer of the • melted sulfur on the surface of the moving Conveyor link (17) is applied » 10982 3/1629 7. The method according to claim 6, characterized in that that you get the pre-cooled sulfur from the Zühlstreppe (10) in an intermediate container (12), which is located deeper, allows it to flow and then withdraws it .aus the intermediate container and .des on the surface movable conveyor belt (17) applies. 8. The method according to claim 3 and 7, characterized in that that the sulfur from the intermediate container (12) is selectively removed and a layer of this sulfur is usually listed on the upper-surface of the moving conveyor member (17) introduced ', that / ater with a thin layer of Y _v. is provided, which is sufficient to prevent the solidified sulfur from adhering to the surface. 9. Device for performing the method, according to a of claims 1 to 8, characterized in that a) that 3 regulating bodies (15 and / or 15 a) are provided, through which the influx of molten sulfur onto the usually overhead surface of the movable Conveyor belt (17) is adjustable b) that this surface is dimensioned and designed so that it forms at least one cooling bath (30) from aqueous coolant allowed on this surface; e) that drive mechanisms are provided by the the sulfur-bearing surface of the conveyor belt (17) can only be passed through the cooling medium of the bath (30) is and d) that a device (29/39) is provided for collecting the solidified or solidified sulfur on the conveyor belt (17).
109823/1629 10. Apparatus for performing the method according to claim 9f characterized in that that a cutting device (38) is provided, through which the sulfur solidified on the conveyor belt (17) into shaped structures of predetermined dimensions can be cut and this device with a device (29/59) for discharging this Structure cooperates with the conveyor belt. 11. Method of solidifying molten sulfur, according to one of claims 1-8, characterized - that additional cooling air is blown onto the surface of the molten sulfur for cooling before it is introduced into the cooling bath (30, 37) . ·. ■ - ■ 12. Method of causing molten sulfur to solidify bring, according to any one of claims 1-8 and 11, thereby marked, that a certain amount of cooling air on the melted Sulfur is inflated after its removal from cooling baths (30, 37). 13 »Device for carrying out the procedure? after a the claims before 1-8, 11 and 12 and / or according to claim 9 or 10, characterized in that that in the longitudinal direction of the conveyor belt (17) distributed sections are formed which alternate with different angles of inclination form inclined or tiltable surfaces ^ which are so dimensioned or inclined or are inclined to alternate the molten sulfur from one inner edge of the Conveyor belt to the other and vice versa from the other 10 9 8 2 3/1629 / 3 rivers to one edge, and that organs are provided which limit the conveyor belt (17) in order to prevent the transverse flow of the molten sulfur over one edge or the other flows out. 14 · Device for performing the method according to claim 13, characterized that · a device (29/39) for discharging the partial or completely 'solidified sulfur from the production. tape (17) is provided. . 15 · "Device for performing the method according to claim 1-14, characterized in that that a Eühltreppe (10) is provided, which consists of substances over which the molten sulfur flows down by its own weight and that an intermediate container (12) the molten sulfur behind the Eühltreppe receives and that a device, preferably a pump (13) for optional removal the molten sulfur from the intermediate container (12) and for applying the sulfur to the surface of the conveyor belt (17) is provided. 16. The device according to claim 15, characterized in that that at least one overflow device (16 and / or 16a) is provided for receiving the molten sulfur from the intermediate container (12) and so from. · Is formed that by gravity a thin wilm of molten sulfur over the overflow weir can escape onto the surface of the movable conveyor belt (17). The patent attorney 109823/1629