CA1208405A - Method for the production of sulphur in granular form - Google Patents
Method for the production of sulphur in granular formInfo
- Publication number
- CA1208405A CA1208405A CA000412736A CA412736A CA1208405A CA 1208405 A CA1208405 A CA 1208405A CA 000412736 A CA000412736 A CA 000412736A CA 412736 A CA412736 A CA 412736A CA 1208405 A CA1208405 A CA 1208405A
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- Prior art keywords
- sulphur
- cooling
- temperature
- coolant
- brought
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Abstract
ABSTRACT OF THE DISCLOSURE
This invention presents a method for the production of sulphur in granular form as well as a device for the carrying out of the invention, by which sulphur can be obtained in granular form in more economic and simpler way, as an end product, having a high breaking strength with a strongly reduced dust buildup during the manufacturing process, as well as a more uniform grain size. This is made possible by providing that the sulphur is first brought to a temperature over 150°C, whereby it reaches viscosity which makes it possible to bring the sulphur to a drop-shaped particle form slowly deposited onto a cooled surface.
By cooling on a cooled surface or a belt cooler in at least two steps, due to a more suitable value of the cooling temperatures, a too rapid cooling and thus undercooling and liquid discharge of the sulphur can be avoided. As a device for carrying out the method, a rotary drop extrusion mold is provided which does not require any great structural demands and enables the granulation of the sulphur according to the method of the present invention in simpler way.
This invention presents a method for the production of sulphur in granular form as well as a device for the carrying out of the invention, by which sulphur can be obtained in granular form in more economic and simpler way, as an end product, having a high breaking strength with a strongly reduced dust buildup during the manufacturing process, as well as a more uniform grain size. This is made possible by providing that the sulphur is first brought to a temperature over 150°C, whereby it reaches viscosity which makes it possible to bring the sulphur to a drop-shaped particle form slowly deposited onto a cooled surface.
By cooling on a cooled surface or a belt cooler in at least two steps, due to a more suitable value of the cooling temperatures, a too rapid cooling and thus undercooling and liquid discharge of the sulphur can be avoided. As a device for carrying out the method, a rotary drop extrusion mold is provided which does not require any great structural demands and enables the granulation of the sulphur according to the method of the present invention in simpler way.
Description
~2~
METHOD FOR THE PRODUCTION OF SULPHUR IN GRANULAR FORM
The invention relates to a method for thè production of sulphur in granular form, wherein heated sulphur, preferably produced by the Clause - process, is divided by bead forming means and cooled.
Various methods are known for the production of sulphur in granular form or in bead form. In one known method, the sulphur produced, e.g. by the Clause process, is directly deposited onto a steel belt and is there subjected to laminar cooling. It has been shown in such methods that an easily handled dry end product is obtained which can be produced at flexible adjustments of the production capacity at a high bulk weight. However, as it turned outt the sulphur has the tendency to form dust.
In another known method, the granulation i5 effected under water, wherein, though fast cooling is obtained, the end product is wet, porous and fragile. These end products, therefore, also had the tendency of forming dust due to their fragility. Fur-ther disadvantage of this method is in water pollution and in that t~e method allows only relatively small bulkweights.
A similar known method~spray cooling in prilling towers~
provides the advantages of very high capacity and of a small dust portion, however, it still has the disadvantages that substan-tial costs are required for investment, and that, furthermore, transport losses occur. The environmental pollution by air pollution caused by the prilling towers is likewise of importance.
It is also known to choose conventional bead forming agents, by which the sulphur is formed into drops or beads. As a disadvantage o same, it has been shown that the sulphur obtained at a temperature between 140 and 150 in the Clause process is a low viscosity and possesses a low surace tension, which~ in turn, produces, on the bead formation with the conventional _ 1 ~2~1~4~5 arrangements, very flat, fragile beads. Besides, the available production capacity is lower.
It is an object of the present invention to provide a technical way whereby sulphur can be successfully produced in a simpler way and can be economically transferred into a bead form without having to cope with the disadvantages of reduced strength, a wet end product or a strong tendency to form dust.
The invention resides in that the sulphur is first heated up to a temperature above 150C and thereupon is brought into the form of drops and then solidified in at least two cool-ing steps at dif~erent cooling temperatures, wherein at no part of the cooling process a predetermined temperature difference betwe~n the sulphur and the coolant is exceeded. It has been shown that such a pxocess for the production of sulphur in granular form does not give rise to the disadvantages referred to above.
Sulphur is usually obtained in the refinery at about 145C and has a relatively low viscosity.
When sulphur is heated before the ~ormation of the drops to a temperature above 150C, preferably between 159 and 163C, it has ~een shown that the drop formation is possible without strong tendency o~ fibre pull, at higher temperatures the sulphur cannot be transformed into drops due to its increased viscosity. On lower temperatures, it has been shown that sulphur is too thin and thus cannot ~e brought to a good bead formation.
By the cooling in a number of cooling steps, good ~ead sizes and a strong end product are obtained. In so doing, a pr~determined temperature di~ference between the sulphur and the coolant is not to be exceeded. Thus, optimum cooling can be achieved since undercooling and thus li~uid discharge is avoided.
It is very advantageous when the beaded sulphur is solidified in three cooling steps. In 50 doing, it is to be observed in each cooling step that the temperature difference ~2~1;1!3~C~S
between the sulphur and the coolant does not exceed the value of at most 90C. P greater temperature difference would give rise to a too fast cooling and would result in undesired pro-perties associated with same.
In a more advantageous way, arrangements can be made that the sulphur is delivered to a first cooling zone without any coolant and then is conveyed to a cooling zone in which the cool-ing is effected by coolant haviny the temperature of between 45 and 55 C and then is further conveyed to a cooling zone wherein the coolant temperature is less than 20C. In the first cooling section, the sulphur is cooled by the surrounding air and is transformed, at a temperature still above 100, into a cooling zone in which the cooling is effected by a cool-ant whose temperature is between 45C and 55C. In the last cooling step, the cooling then proceeds with less than 20C.
The passage through the thrPe cooling zones should take at least the time period of 15 seconds. It is of advantage when a rotary bead forming mold is used for the carrying out of the method for the formation of beads, which is disposed above a conveying belt which passes through cooling ~ones of different temperatures. With such a rotary drop or bead forming mold, the method can be effected in an economic way. The rotary drop forming mold may comprise a cylindric container which is surrounded by a second container rotatable relative to the fixst container, wherein the first container is provided with openings discharging in the direction towards the conveyor belt~
which openings are cyclically aligned with the openings in the second container on the relative rotation of the containers.
The sulphur, heated up to a temperature above 150CJcan then be placed into the inner container, relative to which an outer container is rotated. When the openings of both containers are flush, the hot sulphur is extruded from the opening in :~L2~1~4~Si drop - shaped configuration and falls drop-wise onto the belt disposed below. rrhe sulphur, however, can also be brought within the container to the above mentioned temper-ature if the inner container of the rotary drop-forming mold is suitably heated. On the conveyor belt are then provided different cooling zones wherein the region immediately follow-ing that of the deposition of the sulphur does not require any cooling. The sulphur cools itself and is then passed on the belt into a second region in which the belt is sprayed e.g. by water having the temperature of between 45 and 55C.
In a third section, the conveyor belt is sprayed with water having the temperature of 17C, whereupon, after the passage through the three regions, the solidified sulphur is produced which can be easily released from the belt and, as it has been shown, has a good abrasive resistance.
In the following, the method and the apparatus for carrying out the method will be described in exemplary fashion with refexence to ~he figures. The drawing shows:
Figure 1 - a diagrammatic representation of the method by way of a block diagram;
Figure 2 - a device for the carrying out the invention; and Figure 3 - a detailed representa~ion of the device according to Figure ~.
In Figure 1, the individual method sections are readily visible. As a starting step, sulphur is provided, such as sulphur produced by the Claus~- method. Normally~ the sulphur has the temperature between 140 and 150C and has a relatively low viscosity. The sulphur is ~hen heated by means of a heating device up to a temperatuxe of preferably between 159C and 163C.
Thus, the sulphur is polymerized and increases its viscosity to a substantial degreeO The ~iscosity is still not so high as _ ~ _ ~89L~5 to give rise to the phenomenon of fibre pull during the drop formation. It can thus be formed into drops which are then cooled with a conveyor belt at different cooling zones, where-by the sulphur solidifies. Within the cooling zones, the drops are cooled at different cooling temperatures, preferably, in the first cooling zone without the addition of a coolant. A.s an end product, a solidified, bead-shaped sulphur is obtained which possesses, as a dry end product, a high strength. On a suitable drop forming, the end product also possesses the feature of uniform grain size so that no transportation or handling problems are encountered.
Figure 2 shows a device which is formed in a simple way and can be very advantageously used for carrying out the method as described above. Above a steel belt 1 is arranged a rotary drop forming mold referred to in total with reference numeral 5, to which is delivered sulphur, having suitable te~.perature greater than 150C, preferably between 159 and 163C. The device for heating the sulphur to this temperature is not shown.
The rotary mold 5 consists of an inner container 3 and a container 4 surrounding the former J wherein the outer container 4 can be rotated by a drive device ll relative to the inner container 3. Into the inner container 3 communicates a feeding sleeve 6 and an outlet sleeve 7 as we~l as inlet sleeves 8. By the feeding sleeve 6, a heating agent can be produced for the double wall of the inner container 3, which serves the purpose of obtaining the desired temperature above 160C. Over the inlet sleeve ~ r the liquid sulphur is brought into the interior of the container 3. By the rotating of the outer container 4 xelative to the inner container 3, the sulphur is discharged in a way to be described later, onto the belt l, which passes through cooling zones 12, 13 and 14 having s different temperatures. Inside the cooling zone 12, the sulphur is cooled without the input of a coolant and is then transformed into a cooling zone 13, wherein water is sprayed by a spray device onto an undersurface of the belt 1. The water temper-ature in this region should be between 45 and 55C. Before the end of the belt, one more cooling zone 14 is provided wherein water having the temperature of about 20 is sprayed from under-neath against the belt 1. As can be seen from the cross-sectional view shown in Fig. 3 of the rotary drop forming mold, along the line III - III of Fig. 2, the inner container 3 is provided with openings 15 directed towards the belt 1 and dispo-sed one behind the other. The openings 10 of the outer container extend over its entire periphery, are cyclically aligned with the openings 15 when the outer container 4 is rotated relative to the inner container 3. By this cycl.ic shearing of the sulphur flowing out of openings 15, drops are then formed which are deposited onto the belt 1 and are finally cooled in the above descrLbed way~
The use of such a rotary drop-forming mold for the carrying out of the method allows a very economic production of granular or bead-shapad sulphur, whereby a solid end pro-duct is obtained having a high strength, a uniform particle size and a reduced tendency to form dust, which until now could be ohtained only at a substantially greater expense.
METHOD FOR THE PRODUCTION OF SULPHUR IN GRANULAR FORM
The invention relates to a method for thè production of sulphur in granular form, wherein heated sulphur, preferably produced by the Clause - process, is divided by bead forming means and cooled.
Various methods are known for the production of sulphur in granular form or in bead form. In one known method, the sulphur produced, e.g. by the Clause process, is directly deposited onto a steel belt and is there subjected to laminar cooling. It has been shown in such methods that an easily handled dry end product is obtained which can be produced at flexible adjustments of the production capacity at a high bulk weight. However, as it turned outt the sulphur has the tendency to form dust.
In another known method, the granulation i5 effected under water, wherein, though fast cooling is obtained, the end product is wet, porous and fragile. These end products, therefore, also had the tendency of forming dust due to their fragility. Fur-ther disadvantage of this method is in water pollution and in that t~e method allows only relatively small bulkweights.
A similar known method~spray cooling in prilling towers~
provides the advantages of very high capacity and of a small dust portion, however, it still has the disadvantages that substan-tial costs are required for investment, and that, furthermore, transport losses occur. The environmental pollution by air pollution caused by the prilling towers is likewise of importance.
It is also known to choose conventional bead forming agents, by which the sulphur is formed into drops or beads. As a disadvantage o same, it has been shown that the sulphur obtained at a temperature between 140 and 150 in the Clause process is a low viscosity and possesses a low surace tension, which~ in turn, produces, on the bead formation with the conventional _ 1 ~2~1~4~5 arrangements, very flat, fragile beads. Besides, the available production capacity is lower.
It is an object of the present invention to provide a technical way whereby sulphur can be successfully produced in a simpler way and can be economically transferred into a bead form without having to cope with the disadvantages of reduced strength, a wet end product or a strong tendency to form dust.
The invention resides in that the sulphur is first heated up to a temperature above 150C and thereupon is brought into the form of drops and then solidified in at least two cool-ing steps at dif~erent cooling temperatures, wherein at no part of the cooling process a predetermined temperature difference betwe~n the sulphur and the coolant is exceeded. It has been shown that such a pxocess for the production of sulphur in granular form does not give rise to the disadvantages referred to above.
Sulphur is usually obtained in the refinery at about 145C and has a relatively low viscosity.
When sulphur is heated before the ~ormation of the drops to a temperature above 150C, preferably between 159 and 163C, it has ~een shown that the drop formation is possible without strong tendency o~ fibre pull, at higher temperatures the sulphur cannot be transformed into drops due to its increased viscosity. On lower temperatures, it has been shown that sulphur is too thin and thus cannot ~e brought to a good bead formation.
By the cooling in a number of cooling steps, good ~ead sizes and a strong end product are obtained. In so doing, a pr~determined temperature di~ference between the sulphur and the coolant is not to be exceeded. Thus, optimum cooling can be achieved since undercooling and thus li~uid discharge is avoided.
It is very advantageous when the beaded sulphur is solidified in three cooling steps. In 50 doing, it is to be observed in each cooling step that the temperature difference ~2~1;1!3~C~S
between the sulphur and the coolant does not exceed the value of at most 90C. P greater temperature difference would give rise to a too fast cooling and would result in undesired pro-perties associated with same.
In a more advantageous way, arrangements can be made that the sulphur is delivered to a first cooling zone without any coolant and then is conveyed to a cooling zone in which the cool-ing is effected by coolant haviny the temperature of between 45 and 55 C and then is further conveyed to a cooling zone wherein the coolant temperature is less than 20C. In the first cooling section, the sulphur is cooled by the surrounding air and is transformed, at a temperature still above 100, into a cooling zone in which the cooling is effected by a cool-ant whose temperature is between 45C and 55C. In the last cooling step, the cooling then proceeds with less than 20C.
The passage through the thrPe cooling zones should take at least the time period of 15 seconds. It is of advantage when a rotary bead forming mold is used for the carrying out of the method for the formation of beads, which is disposed above a conveying belt which passes through cooling ~ones of different temperatures. With such a rotary drop or bead forming mold, the method can be effected in an economic way. The rotary drop forming mold may comprise a cylindric container which is surrounded by a second container rotatable relative to the fixst container, wherein the first container is provided with openings discharging in the direction towards the conveyor belt~
which openings are cyclically aligned with the openings in the second container on the relative rotation of the containers.
The sulphur, heated up to a temperature above 150CJcan then be placed into the inner container, relative to which an outer container is rotated. When the openings of both containers are flush, the hot sulphur is extruded from the opening in :~L2~1~4~Si drop - shaped configuration and falls drop-wise onto the belt disposed below. rrhe sulphur, however, can also be brought within the container to the above mentioned temper-ature if the inner container of the rotary drop-forming mold is suitably heated. On the conveyor belt are then provided different cooling zones wherein the region immediately follow-ing that of the deposition of the sulphur does not require any cooling. The sulphur cools itself and is then passed on the belt into a second region in which the belt is sprayed e.g. by water having the temperature of between 45 and 55C.
In a third section, the conveyor belt is sprayed with water having the temperature of 17C, whereupon, after the passage through the three regions, the solidified sulphur is produced which can be easily released from the belt and, as it has been shown, has a good abrasive resistance.
In the following, the method and the apparatus for carrying out the method will be described in exemplary fashion with refexence to ~he figures. The drawing shows:
Figure 1 - a diagrammatic representation of the method by way of a block diagram;
Figure 2 - a device for the carrying out the invention; and Figure 3 - a detailed representa~ion of the device according to Figure ~.
In Figure 1, the individual method sections are readily visible. As a starting step, sulphur is provided, such as sulphur produced by the Claus~- method. Normally~ the sulphur has the temperature between 140 and 150C and has a relatively low viscosity. The sulphur is ~hen heated by means of a heating device up to a temperatuxe of preferably between 159C and 163C.
Thus, the sulphur is polymerized and increases its viscosity to a substantial degreeO The ~iscosity is still not so high as _ ~ _ ~89L~5 to give rise to the phenomenon of fibre pull during the drop formation. It can thus be formed into drops which are then cooled with a conveyor belt at different cooling zones, where-by the sulphur solidifies. Within the cooling zones, the drops are cooled at different cooling temperatures, preferably, in the first cooling zone without the addition of a coolant. A.s an end product, a solidified, bead-shaped sulphur is obtained which possesses, as a dry end product, a high strength. On a suitable drop forming, the end product also possesses the feature of uniform grain size so that no transportation or handling problems are encountered.
Figure 2 shows a device which is formed in a simple way and can be very advantageously used for carrying out the method as described above. Above a steel belt 1 is arranged a rotary drop forming mold referred to in total with reference numeral 5, to which is delivered sulphur, having suitable te~.perature greater than 150C, preferably between 159 and 163C. The device for heating the sulphur to this temperature is not shown.
The rotary mold 5 consists of an inner container 3 and a container 4 surrounding the former J wherein the outer container 4 can be rotated by a drive device ll relative to the inner container 3. Into the inner container 3 communicates a feeding sleeve 6 and an outlet sleeve 7 as we~l as inlet sleeves 8. By the feeding sleeve 6, a heating agent can be produced for the double wall of the inner container 3, which serves the purpose of obtaining the desired temperature above 160C. Over the inlet sleeve ~ r the liquid sulphur is brought into the interior of the container 3. By the rotating of the outer container 4 xelative to the inner container 3, the sulphur is discharged in a way to be described later, onto the belt l, which passes through cooling zones 12, 13 and 14 having s different temperatures. Inside the cooling zone 12, the sulphur is cooled without the input of a coolant and is then transformed into a cooling zone 13, wherein water is sprayed by a spray device onto an undersurface of the belt 1. The water temper-ature in this region should be between 45 and 55C. Before the end of the belt, one more cooling zone 14 is provided wherein water having the temperature of about 20 is sprayed from under-neath against the belt 1. As can be seen from the cross-sectional view shown in Fig. 3 of the rotary drop forming mold, along the line III - III of Fig. 2, the inner container 3 is provided with openings 15 directed towards the belt 1 and dispo-sed one behind the other. The openings 10 of the outer container extend over its entire periphery, are cyclically aligned with the openings 15 when the outer container 4 is rotated relative to the inner container 3. By this cycl.ic shearing of the sulphur flowing out of openings 15, drops are then formed which are deposited onto the belt 1 and are finally cooled in the above descrLbed way~
The use of such a rotary drop-forming mold for the carrying out of the method allows a very economic production of granular or bead-shapad sulphur, whereby a solid end pro-duct is obtained having a high strength, a uniform particle size and a reduced tendency to form dust, which until now could be ohtained only at a substantially greater expense.
Claims (12)
1. A method for the production of sulphur in granular form, wherein heated sulphur is distributed by bead forming apparatus and cooled, characterized in that the sulphur is first brought to a temperature between 158°C
and 163°C and thereupon is brought into a drop-shaped form and then solidified in at least two cooling steps at differ-ent cooling temperatures, wherein in none of the cooling steps a predetermined temperature difference between the sulphur and a respective coolant is exceeded.
and 163°C and thereupon is brought into a drop-shaped form and then solidified in at least two cooling steps at differ-ent cooling temperatures, wherein in none of the cooling steps a predetermined temperature difference between the sulphur and a respective coolant is exceeded.
2. A method according to claim 1, characterized in that the bead-shaped sulphur is brought to the solid-ification temperature in three cooling steps.
3. The method according to claim 1, characterized in that the temperature difference between the sulphur and the coolant does not exceed 90°.
4. The method according to claim 1, characterized in that the sulphur is delivered to a first cooling zone generally devoid of any coolant other than air and then is passed into a cooling zone wherein cooling is effected by a coolant having temperature of between 45 and 55°, and then is delivered to a cooling zone wherein the cooling temperature is about 20°.
5. The method according to claim 1, characterized in that the beaded sulfur is conveyed through the cooling stages for a time period of at least 15 seconds.
6. A method for the production of sulphur in granular form, wherein heated sulphur is distributed by bead forming apparatus and cooled, characterized in that the sulphur is first brought to a temperature between 150°C and 163°C and then is brought into a drop-shaped form and solidified in at least two cooling steps at different cooling temperatures, wherein in any of the cooling steps a temperature difference between the sulphur and a respective coolant does not exceed 90°C.
7. A method according to claim 6, characterized in that the bead-shaped sulphur is brought to the solidification temperature in three cooling steps.
8. The method according to claim 6, characterized in that the sulphur is delivered to a first cooling zone generally devoid of any coolant other than air and is then passed into a cooling zone wherein cooling is effected by a coolant having temperature between 45 and 55°C, and then is delivered to a cooling zone wherein the cooling temperature is about 20°C.
9. The method according to claim 6, characterized in that the beaded sulphur is conveyed through the cooling stages for a time period of at least 15 seconds.
10. Apparatus for carrying out the method of claim 1, characterized in that for the formation of beads a rotary bead forming mold is used which is arranged above a cooling conveyor belt passing over cooling zones of different temperatures.
11. Apparatus according to claim 10, characterized in that the rotary bead forming mold comprises a cylindric container surrounded by a second container rotatable relative to the first container, wherein the first container is provided with openings in the direction towards the conveyor belt, which are cyclically brought into communication with openings in the second container on relative rotation between the containers.
12. Apparatus according to claim 10 or 11, characterized in that water is used as the coolant, which is sprayed in different cooling zones at the corresponding temperatures against the underside of the belt.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA000412736A CA1208405A (en) | 1982-10-04 | 1982-10-04 | Method for the production of sulphur in granular form |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA000412736A CA1208405A (en) | 1982-10-04 | 1982-10-04 | Method for the production of sulphur in granular form |
Publications (1)
Publication Number | Publication Date |
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CA1208405A true CA1208405A (en) | 1986-07-29 |
Family
ID=4123710
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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CA000412736A Expired CA1208405A (en) | 1982-10-04 | 1982-10-04 | Method for the production of sulphur in granular form |
Country Status (1)
Country | Link |
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CA (1) | CA1208405A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5286181A (en) * | 1991-04-26 | 1994-02-15 | Berndorf Belt Systems, Inc. | Extrusion apparatus having a nozzle-headed drum |
US5788896A (en) * | 1997-02-27 | 1998-08-04 | Alberta Research Council | Method of producing micron sized sulphur granules |
-
1982
- 1982-10-04 CA CA000412736A patent/CA1208405A/en not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5286181A (en) * | 1991-04-26 | 1994-02-15 | Berndorf Belt Systems, Inc. | Extrusion apparatus having a nozzle-headed drum |
US5788896A (en) * | 1997-02-27 | 1998-08-04 | Alberta Research Council | Method of producing micron sized sulphur granules |
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