CA1250314A - Urea synthesizing process utilizing silicon carbide materials in its equipment - Google Patents
Urea synthesizing process utilizing silicon carbide materials in its equipmentInfo
- Publication number
- CA1250314A CA1250314A CA000375434A CA375434A CA1250314A CA 1250314 A CA1250314 A CA 1250314A CA 000375434 A CA000375434 A CA 000375434A CA 375434 A CA375434 A CA 375434A CA 1250314 A CA1250314 A CA 1250314A
- Authority
- CA
- Canada
- Prior art keywords
- silicon carbide
- equipment
- materials
- synthesizing process
- urea synthesizing
- 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.)
- Expired
Links
- 239000000463 material Substances 0.000 title claims abstract description 40
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 title claims abstract description 24
- 239000004202 carbamide Substances 0.000 title claims abstract description 24
- 230000002194 synthesizing effect Effects 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 19
- 229910010271 silicon carbide Inorganic materials 0.000 title claims description 28
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 title claims description 26
- 230000007797 corrosion Effects 0.000 claims abstract description 15
- 238000005260 corrosion Methods 0.000 claims abstract description 15
- 230000003628 erosive effect Effects 0.000 claims abstract description 11
- 239000000126 substance Substances 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000000576 coating method Methods 0.000 claims description 2
- 239000012530 fluid Substances 0.000 abstract description 12
- 238000012545 processing Methods 0.000 abstract description 9
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 7
- 229910052726 zirconium Inorganic materials 0.000 description 7
- 229910001093 Zr alloy Inorganic materials 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 229940095054 ammoniac Drugs 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 208000036366 Sensation of pressure Diseases 0.000 description 1
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000007750 plasma spraying Methods 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K25/00—Details relating to contact between valve members and seats
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/02—Apparatus characterised by being constructed of material selected for its chemically-resistant properties
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
- C07C273/04—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds from carbon dioxide and ammonia
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K27/00—Construction of housing; Use of materials therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J2219/02—Apparatus characterised by their chemically-resistant properties
- B01J2219/0204—Apparatus characterised by their chemically-resistant properties comprising coatings on the surfaces in direct contact with the reactive components
- B01J2219/0218—Apparatus characterised by their chemically-resistant properties comprising coatings on the surfaces in direct contact with the reactive components of ceramic
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Lift Valve (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
- Details Of Valves (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
Abstract Since a urea synthesizing process brings excessive corrosion to equipment caused by processing fluids, equipment coated with materials of high resistance to corrosion and cavitation-induced erosion is used in portions susceptible to excessive corrosion and cavitation-induced erosion, accord-ing to the present invention.
Description
~z j - SPECIFICATION
Title of the Invention Urea Synthesizing Process Utilizing Silicon Carbide Materials in its Equipment il f~ Background of the Invention The present invention relates to a urea synthesiz-ing process utilizing silicon carbide materials in its equipment.
Corrosion of structural materials constitutes a serious problem in a plant since a urea synthesizing process involves the handling of high temperature, high pressure and highly corrosive processing fluid. In particular, a pressure reducing valve requires the use of special material, the valve being located between a synthesizing tower in which processing fluid pressurized to 150 - 250 atoms is introduced for synthesizing urea and a decomposition vessel in which unreacted ammonium and carbon dioxide are separated and recovered. The reason why special material is requires is that highly corrosive, processing fluid of high temperature and high pressure is fed in, its pressure being reduced by the pressure reducing valve, and thereafter flows out with high velocity. Therefore, excessive chemical and physical damage arises in portions of the valve from corrosion and erosion due to cavitation, rendering the life of a pressure reducing valve of ordinary material very short.
Conventionally, stainless steel or zirconium and .,~
lZ~V314 "
zirconium alloy have been the materials used for urea synthesizing process equipment.
For instance, austenitic stainless steel, when used as a material for process equipment, has a problem because its insufficient corrosion-resistance causes the dissolution of material due to corrosion during usage, result-ing in premature failure of the pressure reducing valve.
On the other hand, zirconium and zirconium alloy have tentatively been used for actual application since they have high corrosion-resistance in the environment of synthe-sizing urea. However, the hardness of zirconium and zirconium alloy is low; for instance, the hardness of zirconium of 99.5%
purity is as low as 150 Brinell Hardness, almost the same as that of mild steel. Therefore, zirconium and zirconium alloy are vulnerable to physical attack and, for instance, in a urea synthesizing plant in which a pressure reducing valve of zirconium is installed, the valve is rapidly damaged by erosion due to cavitation during the water or ammoniac water circulation operation prior to producing urea, resulting in the loss of function of the valve. In order to alleviate the problem lately, a pressure reducing valve of such physi-cally strong material as stainless steel is used during the water or ammoniac water circulation operation, and thereafter the valve is replaced with one of highly corrosion-resistant material such as zirconium before starting the urea producing process. As heretofore mentioned, the present practice is that the valve of one material is replaced with that of another material depending on the type of fluid flowing through )314 the valve, but this practice naturally makes the operation of a urea synthesizing plant inconvenient and inefficient and, at the same time, creates the possibility of unexpect-ed damage caused by the variation of operating conditions as well as the problem of safety of a plant being operated under high temperature and high pressure conditions.
Brief Summarv of the Invention An object of an aspect of the present invention is to provide a urea synthesizing process which permits long sustaining operation with high stability irrespective of operational conditions by resolving the aforementioned problems of erosion due to cavitation and corrosion which occur in a urea synthesizing process by utilizing silicon carbide in portions vulnerable to damage.
According to one aspect of this invention there is provided a urea synthesizing process wherein materials of silicon carbides are used in equipment thereof, charac-terized in that said materials of silicon carbide are used in portions of equipment which are susceptible to corrosion and cavitation-induced erosion.
Brief DescriPtion- of the Drawing The accompanying drawing is a schematic section of an embodiment of the present invention.
Detailed Description of the Invention As heretofore mentioned, a urea synthesizing process tends to incur excessive corrosion and erosion due to cavitation in such equipment as a pressure reducing valve. In order to prevent such damages from occurring, it is necessary to use materials having high corrosion-resistance and high wear-resistance in equipment sus-ceptible to such corrosion and erosion due to cavita-tion as mentioned above. Silicon carbide 12~;~31~
is a material meeting these requirements. The silicon carbide materials include either a material which is made solely of silicon carbide (simple silicon carbide) or a coated material in which a base material of metals, cerâmics or graphite is coated with silicon carbide by such a coating technique as plasma spraying, chemical vapor depositing or physical vapor depositing. A silicon carbide material having a high density of not less than 2.9 Specific Gravity is preferable to other silicon carbide materials.
Now an embodiment of the present invention will be described hereunder, with reference to the accompanying drawing. A silicon carbide material is used in the pressure reducing valve of the embodiment. The drawing is a schematic section of the pressure reducing valve, comprising a valve body 1, fluid inlet port 2, plug valve 3 and valve seat ring 5. A processing fluid under high temperature and high pres-sure enters the valve body 1 through the inlet port 2 and flows through the clearance between the tip 4 of the plug valve 3 and the upper edge of inner surface 6 of the valve seat ring 5, the pressure of the processing fluid then being reduced. The rate of pressure reduction is controlled by up-and-down movement of the plug valve 3. In actual opera-tion, the tip 4 of the plug valve and the inner surface 6 are exposed to the processing fluid at a high speed and subject to the excessive corrosion and the erosion due to cavitation.
Thus materials having high corrosion-resistance and high wear-resistance are required to be used in those portion of the pressure reducing valve. A silicon carbide material is used .
31~
in embodiments of the present invention.
Only a pressure reducing valve was discussed in the above example, howeveT, silicon carbide materials can be used in any portion of such equipment which is exposed to highly corrosive processing fluid in urea synthesizing plants, especially being effective in areas where high velocity fluid is encountered. For instance, use of silicon carbide mate-rials is very effective in valves in recycling lines.
In regard to the present invention, processes in which silicon carbide materials are used are the conventional urea synthesizing processes.
According to the present invention, the use of highly corrosion-resistant and wear-resistant silicon carbide in urea synthesizing plants has eliminated the need for replacing valves which are damaged from corrosion or cavitation-induced erosion during operation, or the need for changing valves to those of different materials depending on the type of process-ing fluid used, these needs arising from the lack of appro-priate materials. The use of silicon carbide also has prevented damage caused by varying operational conditions from occurring, improved the safety and stability in the operation of a urea synthesizing plant under high temperature and high pressure conditions and promoted operational effi-ciency of the plant.
Title of the Invention Urea Synthesizing Process Utilizing Silicon Carbide Materials in its Equipment il f~ Background of the Invention The present invention relates to a urea synthesiz-ing process utilizing silicon carbide materials in its equipment.
Corrosion of structural materials constitutes a serious problem in a plant since a urea synthesizing process involves the handling of high temperature, high pressure and highly corrosive processing fluid. In particular, a pressure reducing valve requires the use of special material, the valve being located between a synthesizing tower in which processing fluid pressurized to 150 - 250 atoms is introduced for synthesizing urea and a decomposition vessel in which unreacted ammonium and carbon dioxide are separated and recovered. The reason why special material is requires is that highly corrosive, processing fluid of high temperature and high pressure is fed in, its pressure being reduced by the pressure reducing valve, and thereafter flows out with high velocity. Therefore, excessive chemical and physical damage arises in portions of the valve from corrosion and erosion due to cavitation, rendering the life of a pressure reducing valve of ordinary material very short.
Conventionally, stainless steel or zirconium and .,~
lZ~V314 "
zirconium alloy have been the materials used for urea synthesizing process equipment.
For instance, austenitic stainless steel, when used as a material for process equipment, has a problem because its insufficient corrosion-resistance causes the dissolution of material due to corrosion during usage, result-ing in premature failure of the pressure reducing valve.
On the other hand, zirconium and zirconium alloy have tentatively been used for actual application since they have high corrosion-resistance in the environment of synthe-sizing urea. However, the hardness of zirconium and zirconium alloy is low; for instance, the hardness of zirconium of 99.5%
purity is as low as 150 Brinell Hardness, almost the same as that of mild steel. Therefore, zirconium and zirconium alloy are vulnerable to physical attack and, for instance, in a urea synthesizing plant in which a pressure reducing valve of zirconium is installed, the valve is rapidly damaged by erosion due to cavitation during the water or ammoniac water circulation operation prior to producing urea, resulting in the loss of function of the valve. In order to alleviate the problem lately, a pressure reducing valve of such physi-cally strong material as stainless steel is used during the water or ammoniac water circulation operation, and thereafter the valve is replaced with one of highly corrosion-resistant material such as zirconium before starting the urea producing process. As heretofore mentioned, the present practice is that the valve of one material is replaced with that of another material depending on the type of fluid flowing through )314 the valve, but this practice naturally makes the operation of a urea synthesizing plant inconvenient and inefficient and, at the same time, creates the possibility of unexpect-ed damage caused by the variation of operating conditions as well as the problem of safety of a plant being operated under high temperature and high pressure conditions.
Brief Summarv of the Invention An object of an aspect of the present invention is to provide a urea synthesizing process which permits long sustaining operation with high stability irrespective of operational conditions by resolving the aforementioned problems of erosion due to cavitation and corrosion which occur in a urea synthesizing process by utilizing silicon carbide in portions vulnerable to damage.
According to one aspect of this invention there is provided a urea synthesizing process wherein materials of silicon carbides are used in equipment thereof, charac-terized in that said materials of silicon carbide are used in portions of equipment which are susceptible to corrosion and cavitation-induced erosion.
Brief DescriPtion- of the Drawing The accompanying drawing is a schematic section of an embodiment of the present invention.
Detailed Description of the Invention As heretofore mentioned, a urea synthesizing process tends to incur excessive corrosion and erosion due to cavitation in such equipment as a pressure reducing valve. In order to prevent such damages from occurring, it is necessary to use materials having high corrosion-resistance and high wear-resistance in equipment sus-ceptible to such corrosion and erosion due to cavita-tion as mentioned above. Silicon carbide 12~;~31~
is a material meeting these requirements. The silicon carbide materials include either a material which is made solely of silicon carbide (simple silicon carbide) or a coated material in which a base material of metals, cerâmics or graphite is coated with silicon carbide by such a coating technique as plasma spraying, chemical vapor depositing or physical vapor depositing. A silicon carbide material having a high density of not less than 2.9 Specific Gravity is preferable to other silicon carbide materials.
Now an embodiment of the present invention will be described hereunder, with reference to the accompanying drawing. A silicon carbide material is used in the pressure reducing valve of the embodiment. The drawing is a schematic section of the pressure reducing valve, comprising a valve body 1, fluid inlet port 2, plug valve 3 and valve seat ring 5. A processing fluid under high temperature and high pres-sure enters the valve body 1 through the inlet port 2 and flows through the clearance between the tip 4 of the plug valve 3 and the upper edge of inner surface 6 of the valve seat ring 5, the pressure of the processing fluid then being reduced. The rate of pressure reduction is controlled by up-and-down movement of the plug valve 3. In actual opera-tion, the tip 4 of the plug valve and the inner surface 6 are exposed to the processing fluid at a high speed and subject to the excessive corrosion and the erosion due to cavitation.
Thus materials having high corrosion-resistance and high wear-resistance are required to be used in those portion of the pressure reducing valve. A silicon carbide material is used .
31~
in embodiments of the present invention.
Only a pressure reducing valve was discussed in the above example, howeveT, silicon carbide materials can be used in any portion of such equipment which is exposed to highly corrosive processing fluid in urea synthesizing plants, especially being effective in areas where high velocity fluid is encountered. For instance, use of silicon carbide mate-rials is very effective in valves in recycling lines.
In regard to the present invention, processes in which silicon carbide materials are used are the conventional urea synthesizing processes.
According to the present invention, the use of highly corrosion-resistant and wear-resistant silicon carbide in urea synthesizing plants has eliminated the need for replacing valves which are damaged from corrosion or cavitation-induced erosion during operation, or the need for changing valves to those of different materials depending on the type of process-ing fluid used, these needs arising from the lack of appro-priate materials. The use of silicon carbide also has prevented damage caused by varying operational conditions from occurring, improved the safety and stability in the operation of a urea synthesizing plant under high temperature and high pressure conditions and promoted operational effi-ciency of the plant.
Claims
What is Claimed is (1) A urea synthesizing process wherein materials of silicon carbides are used in equipment thereof, charac-terized in that said materials of silicon carbide are used in portions of equipment which are susceptible to corrosion and cavitation-induced erosion.
(2) A urea synthesizing process according to Claim (1), wherein materials of silicon carbide are used in equip-ment thereof, characterized in that said silicon carbide is used as a simple substance.
(3) A urea synthesizing process according to Claim (1), wherein silicon carbide materials are used in equipment thereof, characterized in that said silicon carbide is used as a coating material.
(4) A urea synthesizing process according to any of Claims (1) through (3), wherein materials of silicon carbide are used in equipment thereof, characterized in that said materials of silicon carbide are used in pressure reducing valves.
(2) A urea synthesizing process according to Claim (1), wherein materials of silicon carbide are used in equip-ment thereof, characterized in that said silicon carbide is used as a simple substance.
(3) A urea synthesizing process according to Claim (1), wherein silicon carbide materials are used in equipment thereof, characterized in that said silicon carbide is used as a coating material.
(4) A urea synthesizing process according to any of Claims (1) through (3), wherein materials of silicon carbide are used in equipment thereof, characterized in that said materials of silicon carbide are used in pressure reducing valves.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP48641/1980 | 1980-04-15 | ||
| JP4864180A JPS56147756A (en) | 1980-04-15 | 1980-04-15 | Synthetic method of urea using silicon carbide material in apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1250314A true CA1250314A (en) | 1989-02-21 |
Family
ID=12808989
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000375434A Expired CA1250314A (en) | 1980-04-15 | 1981-04-14 | Urea synthesizing process utilizing silicon carbide materials in its equipment |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS56147756A (en) |
| BR (1) | BR8102284A (en) |
| CA (1) | CA1250314A (en) |
| DE (1) | DE3114218A1 (en) |
| FR (1) | FR2480280A1 (en) |
| GB (1) | GB2073751B (en) |
| IN (1) | IN155840B (en) |
| IT (1) | IT1137354B (en) |
| NL (1) | NL8101499A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2608234B2 (en) * | 1992-02-26 | 1997-05-07 | 東洋エンジニアリング株式会社 | Pressure reducing valve for urea synthesis plant |
| US20110033018A1 (en) * | 2009-08-10 | 2011-02-10 | Caldera Engineering, Lc | Method for bonding ceramic materials |
| US9446367B2 (en) | 2014-08-15 | 2016-09-20 | Rec Silicon Inc | Joint design for segmented silicon carbide liner in a fluidized bed reactor |
| US9238211B1 (en) | 2014-08-15 | 2016-01-19 | Rec Silicon Inc | Segmented silicon carbide liner |
| US9662628B2 (en) | 2014-08-15 | 2017-05-30 | Rec Silicon Inc | Non-contaminating bonding material for segmented silicon carbide liner in a fluidized bed reactor |
| WO2023191620A1 (en) * | 2022-03-28 | 2023-10-05 | Stamicarbon B.V. | Urea plant with valve; urea production process; use and method |
-
1980
- 1980-04-15 JP JP4864180A patent/JPS56147756A/en active Pending
-
1981
- 1981-03-25 IN IN323/CAL/81A patent/IN155840B/en unknown
- 1981-03-26 NL NL8101499A patent/NL8101499A/en not_active Application Discontinuation
- 1981-04-01 GB GB8110277A patent/GB2073751B/en not_active Expired
- 1981-04-08 DE DE19813114218 patent/DE3114218A1/en not_active Withdrawn
- 1981-04-14 BR BR8102284A patent/BR8102284A/en unknown
- 1981-04-14 IT IT21139/81A patent/IT1137354B/en active
- 1981-04-14 CA CA000375434A patent/CA1250314A/en not_active Expired
- 1981-04-15 FR FR8107634A patent/FR2480280A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2480280A1 (en) | 1981-10-16 |
| FR2480280B1 (en) | 1983-07-01 |
| JPS56147756A (en) | 1981-11-16 |
| IT8121139A0 (en) | 1981-04-14 |
| IT1137354B (en) | 1986-09-10 |
| NL8101499A (en) | 1981-11-02 |
| GB2073751B (en) | 1984-02-01 |
| GB2073751A (en) | 1981-10-21 |
| BR8102284A (en) | 1981-12-01 |
| DE3114218A1 (en) | 1982-03-04 |
| IN155840B (en) | 1985-03-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |