GB1570776A - Desulphurizing fluid materials - Google Patents
Desulphurizing fluid materials Download PDFInfo
- Publication number
- GB1570776A GB1570776A GB8315/78A GB831578A GB1570776A GB 1570776 A GB1570776 A GB 1570776A GB 8315/78 A GB8315/78 A GB 8315/78A GB 831578 A GB831578 A GB 831578A GB 1570776 A GB1570776 A GB 1570776A
- Authority
- GB
- United Kingdom
- Prior art keywords
- rare earth
- gases
- sulphur
- oxygen potential
- fluid material
- 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
- 239000012530 fluid Substances 0.000 title claims description 27
- 239000000463 material Substances 0.000 title claims description 22
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 49
- 150000002910 rare earth metals Chemical class 0.000 claims description 44
- 238000000034 method Methods 0.000 claims description 40
- 239000007789 gas Substances 0.000 claims description 31
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 22
- 239000001301 oxygen Substances 0.000 claims description 22
- 229910052760 oxygen Inorganic materials 0.000 claims description 22
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 20
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 claims description 19
- 239000005864 Sulphur Substances 0.000 claims description 18
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 16
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 12
- 239000004291 sulphur dioxide Substances 0.000 claims description 10
- 235000010269 sulphur dioxide Nutrition 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 9
- -1 sulphur compound Chemical class 0.000 claims description 9
- 239000000047 product Substances 0.000 claims description 7
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims description 7
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 239000003245 coal Substances 0.000 claims description 6
- 230000007613 environmental effect Effects 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 239000012141 concentrate Substances 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 4
- 239000007795 chemical reaction product Substances 0.000 claims description 4
- 230000000694 effects Effects 0.000 claims description 4
- 239000003546 flue gas Substances 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000003921 oil Substances 0.000 claims description 4
- 238000005201 scrubbing Methods 0.000 claims description 4
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 3
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 3
- 239000012159 carrier gas Substances 0.000 claims description 3
- 239000011261 inert gas Substances 0.000 claims description 3
- 238000002347 injection Methods 0.000 claims description 3
- 239000007924 injection Substances 0.000 claims description 3
- 150000004763 sulfides Chemical class 0.000 claims description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 2
- 241001465754 Metazoa Species 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 2
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 2
- 239000004566 building material Substances 0.000 claims description 2
- 239000001175 calcium sulphate Substances 0.000 claims description 2
- 235000011132 calcium sulphate Nutrition 0.000 claims description 2
- 239000004295 calcium sulphite Substances 0.000 claims description 2
- 235000010261 calcium sulphite Nutrition 0.000 claims description 2
- 239000000571 coke Substances 0.000 claims description 2
- 239000000470 constituent Substances 0.000 claims description 2
- 238000011109 contamination Methods 0.000 claims description 2
- 230000001419 dependent effect Effects 0.000 claims description 2
- 230000001066 destructive effect Effects 0.000 claims description 2
- 230000008030 elimination Effects 0.000 claims description 2
- 238000003379 elimination reaction Methods 0.000 claims description 2
- 239000004744 fabric Substances 0.000 claims description 2
- 238000005188 flotation Methods 0.000 claims description 2
- 239000002803 fossil fuel Substances 0.000 claims description 2
- 239000000446 fuel Substances 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 239000004571 lime Substances 0.000 claims description 2
- 239000007788 liquid Substances 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims description 2
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 239000002244 precipitate Substances 0.000 claims description 2
- 238000001556 precipitation Methods 0.000 claims description 2
- 230000000135 prohibitive effect Effects 0.000 claims description 2
- 230000005180 public health Effects 0.000 claims description 2
- 230000009467 reduction Effects 0.000 claims description 2
- 230000008929 regeneration Effects 0.000 claims description 2
- 238000011069 regeneration method Methods 0.000 claims description 2
- 210000002345 respiratory system Anatomy 0.000 claims description 2
- 239000002893 slag Substances 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 claims description 2
- 239000001117 sulphuric acid Substances 0.000 claims description 2
- 235000011149 sulphuric acid Nutrition 0.000 claims description 2
- 239000002912 waste gas Substances 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/48—Sulfur compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/48—Sulfur compounds
- B01D53/52—Hydrogen sulfide
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
- C21C1/025—Agents used for dephosphorising or desulfurising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
- C21C7/0645—Agents used for dephosphorising or desulfurising
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Treating Waste Gases (AREA)
- Gasket Seals (AREA)
Description
(54) DESULPHURIZING FLUID MATERIALS
(71) We, MOLYCORP INC., a corporation organised and existing under the laws of the State of Delaware, United
States of America, of 6 Corporate Park
Drive White Plains, New York 10604,
United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
This invention relates to methods of desulphurizing fluid materials and particularly to a method of externally desulphurizing fluids such as molten iron and steel, stack gases, coal gases and coal liquification products using rare earth fluorocarbonates or rare earth oxyfluorides preferably in a substantially dry process.
This invention is an improvement in or modification of the invention described in our copending Application No. 46118/77 (Serial No. 1552507) which claims a method of desulphurizing iron or steel, comprising the steps of: (a) reacting the sulphur to be removed with a rare earth oxide in the presence of a separate deoxidizing agent or a deoxidizing atmosphere to form a rare earth sulphide and/or rare earth oxysulphide; and
(b) removing the sulphide and/or oxysulphide.
The improvement or modification provided by this invention is based on the observation that instead of the rare earth oxide there may be used a rare earth fluorocarbonate or oxyfluoride, provided the desulphurization reaction is carried out at a low oxygen potential. Under those conditions the treatment is applicable to all sulphur-containing fluids.
This invention accordingly provides a method of desulphurizing a fluid material comprising the steps of:
(a) reacting the sulphur in the fluid material with a rare earth fluorocarbonate and/or a rare earth oxyfluoride at low oxygen potential to form a rare earth sulphide and/or a rare earth oxysulphide; and
(b) removing the sulphide and/or oxysulphide.
Although the method according to this invention is suited to the desulphurization of any fluid material, the following discussion is confined, for the purpose of illustration, to the two most pressing problems of desulphurization which industry presently faces, i.e. the desulphurization of molten iron and steel baths and the desulphurization of stack gases.
In the desulphurization of molten iron and steel by the process of this invention the rate earth oxyfluoride and/or the rare earth fluorocarbonate is preferably reacted with the sulphur in the molten metal in the presence of a deoxidizing agent. The rare earth oxyfluoride/ fluorocarbonate may be in the form of a Bastnasite concentrate.
Preferably, the hot metal is treated in a ladle or transfer car with the rare earth oxyfluoride or fluorocarbonate, by the simple addition and mixing of the rare earth oxyfluoride or fluorocarbonate, by an injection technique in which the rare earth oxyfluoride or fluorocarbonate is injected into the molten bath in a carrier gas such as an argon or nitrogen or by the use of an "active lining" i.e., a rare earth oxyfluoride or fluorocarbonate lining in the vessel. The techniques used are exactly the same as those taught in our copening
Application No. 46118/77 (Serial No.
1552507). For example, when the deoxidizing agent is carbon the oxygen potential is preferably maintained at a low level by reducing the partial pressure of CO, advantageously to below 0.1 atmosphere.
This may be achieved by adding the rare earth fluorocarbonate and/or oxyfluoride to the fluid material subject to a vacuum sufficient to maintain the partial pressure of CO below 0.1 atmosphere or, in the injection technique described above, by using a stream of inert carrier gas sufficient to dilute CO formed in the reaction to below 0.1 atmosphere. Another method of controlling the oxygen potential is by controlling the CO/CO2 or H2/H20 ratios.
Similarly, the problem of desulphurizing gases is one of the oldest recognized problems in environmental chemistry. It dates back to the beginning of the utilization of fossil fuels for home heating and for industrial power. Sulphur dioxide is the primary sulphur compound which has been recognized as the problem in environmental control. Sulphur dioxide is a constituent in many waste gases such as flue gases, off gases from various chemical manufacturing processes, stack gases from coal and oil burning furnaces and boilers, smelter gases, ore roaster gases, coke gases and the like. Contamination of the atmosphere by sulphur dioxide, whether present in dilute concentrations of 0.05 of 0.3 volume percent as in power plant flue gases or in higher amounts of up to 10% as in ore roaster gases, has been a public health and environmental problem for many years due to its effect on the respiratory system of animals and humans, its destructive effect on plant life and its corrosive attack on metals, fabrics and building materials.
The reduction or elimination of the sulphur dioxide from gases emitted into the atmosphere is an essential key to the successful use of the world's abundant fuels (coal and high sulphur oils). Thus many methods have been proposed for the desulphurization of gases. Most methods which have been proposed are technically feasible but their expense is in most cases completely prohibitive. The most commonly proposed methods involve scrubbing the gases with water and precipitation of the sulphur dioxide with lime as calcium sulphate or sulphite, depending upon the process involved. Unfortunately, the expense of scrubbing the vast amounts of gas involved and disposing of the resulting precipitate is extremely expensive.
The present invention lies in the discovery that rare earth fluorocarbonates are rare earth oxyfluorides will, at low oxygen potential, remove sulphur from gases and will in turn give up the sulphides at high oxygen potential so that they may be regenerated with the production of a gas high in sulphur oxides from which elemental sulphur, sulphuric acid and like useful products can be obtained.
The ability of Bastnasite concentrates
(complex rare earth fluorocarbonates and rare earth oxyfluorides) to transform to oxysulphide and sulphide under conditions of low oxygen potential has been established thermodynamically and experimentally by us.
In all cases the chemical reactions are analogous to those disclosed in our copending Application No. 46118/77 (Serial No. 1552507) in connection with the use of rare earth oxides.
In the case of liquid reactions, such as in the treatment of molten iron or steel, the product sulphide or oxysulphide will either be fixed in an 'active' lining or removed by flotation and absorbed into the slag cover and vessel lining depending upon the process used for introducing the rare earth oxyfluoride or fluorocarbonate.
The products of desulphurization of carbon saturated iron with rare earth fluorocarbonates and oxyfluorides is dependent on the partial pressure of
CO(pCO) and the Henrian sulphur activity in the metal (hs).
The rare earth compounds used in the method of the invention may be recovered and, if desired, re-used. For example the rare earth sulphide and/or oxysulphide reaction products may be removed from the fluid material, regenerated with oxygen and returned to the fluid system for further desulphurization. Regeneration of the reaction products may be achieved by converting the rare earth sulphides or oxysulphides at high oxygen potential to rare earth oxides.
WHAT WE CLAIM IS:
1. A method of desulphurizing a fluid material comprising the steps of:
(a) reacting the sulphur in the fluid material with a rare earth fluorocarbonate and/or a rare earth oxyfluoride at low oxygen potential to form a rare earth sulphide and/or a rare earth oxysulphide; and
(b) removing the sulphide and/or oxysulphide;
2. A method according to claim 1, wherein the sulphur in the fluid materials is reacted with a Bastnasite concentrate.
3. A method according to claim 1, wherein the oxygen potential is maintained at a low level by reducing the partial pressure of CO.
4. A method according to claim 3, wherein the partial pressure of CO is maintained below 0.1 atmosphere.
5. A method according to claim 1, wherein the rare earth fluorocarbonate and/or oxyfluoride is added to the fluid material by injecting the rare earth fluorocarbonate and/or oxyfluoride into the fluid material in a stream of inert gas sufficient to dilute carbon monoxide formed in the reaction to below 0.1
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (10)
1. A method of desulphurizing a fluid material comprising the steps of:
(a) reacting the sulphur in the fluid material with a rare earth fluorocarbonate and/or a rare earth oxyfluoride at low oxygen potential to form a rare earth sulphide and/or a rare earth oxysulphide; and
(b) removing the sulphide and/or oxysulphide;
2. A method according to claim 1, wherein the sulphur in the fluid materials is reacted with a Bastnasite concentrate.
3. A method according to claim 1, wherein the oxygen potential is maintained at a low level by reducing the partial pressure of CO.
4. A method according to claim 3, wherein the partial pressure of CO is maintained below 0.1 atmosphere.
5. A method according to claim 1, wherein the rare earth fluorocarbonate and/or oxyfluoride is added to the fluid material by injecting the rare earth fluorocarbonate and/or oxyfluoride into the fluid material in a stream of inert gas sufficient to dilute carbon monoxide formed in the reaction to below 0.1
atmosphere.
6. A method according to claim 5, wherein the inert gas is nitrogen.
7. A method according to claim 1, wherein the rare earth fluorocarbonate and/or oxyfluoride is added to the fluid material subject to a vacuum sufficient to maintain the partial pressure of carbon monoxide below 0.1 atmosphere.
8. A method according to any preceding claim, wherein the rare earth sulphide and/or oxysulphide is removed from the fluid material, regenerated with oxygen and returned to the fluid system for further desulphurization.
9. A method according to claim 1 for desulphurizing gases, wherein the oxygen potential is maintained at a low level by controlling the CO/CO2 or H2/H20 ratios.
10. A method according to claim 1 for desulphurizing gases, wherein the removed rare earth oxysulphides and sulphides are regenerated at high oxygen potential to rare earth oxides.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US83888877A | 1977-10-03 | 1977-10-03 | |
US05/838,945 US4161400A (en) | 1976-07-15 | 1977-10-03 | Methods of desulphurizing fluid materials |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1570776A true GB1570776A (en) | 1980-07-09 |
Family
ID=27126069
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB8315/78A Expired GB1570776A (en) | 1977-10-03 | 1978-03-02 | Desulphurizing fluid materials |
Country Status (6)
Country | Link |
---|---|
JP (1) | JPS5451976A (en) |
CA (1) | CA1077682A (en) |
DE (1) | DE2756201C3 (en) |
FR (1) | FR2404676A2 (en) |
GB (1) | GB1570776A (en) |
IT (1) | IT1155781B (en) |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB718750A (en) * | 1951-10-31 | 1954-11-17 | Molybdenum Corp | Manufacture of iron and steel and products obtained thereby |
FR1108850A (en) * | 1953-07-16 | 1956-01-18 | Molybdenum Corp | Production of irons and steels and their compositions |
US2863755A (en) * | 1957-04-22 | 1958-12-09 | Union Carbide Corp | Oil-treated calcium carbide for desulfurization of iron |
SE341412B (en) * | 1969-07-15 | 1971-12-27 | Asea Ab | |
GB1453717A (en) * | 1973-08-17 | 1976-10-27 | British Steel Corp | Manufacture of steel |
US4045371A (en) * | 1974-05-07 | 1977-08-30 | Exxon Research And Engineering Company | Process for preparing a gas desulfurization sorbent |
US3960616A (en) * | 1975-06-19 | 1976-06-01 | Armco Steel Corporation | Rare earth metal treated cold rolled, non-oriented silicon steel and method of making it |
-
1977
- 1977-12-16 DE DE2756201A patent/DE2756201C3/en not_active Expired
-
1978
- 1978-01-20 IT IT47733/78A patent/IT1155781B/en active
- 1978-02-23 CA CA297,627A patent/CA1077682A/en not_active Expired
- 1978-03-02 GB GB8315/78A patent/GB1570776A/en not_active Expired
- 1978-03-02 FR FR7805968A patent/FR2404676A2/en active Pending
- 1978-04-05 JP JP3931878A patent/JPS5451976A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
DE2756201C3 (en) | 1981-03-26 |
CA1077682A (en) | 1980-05-20 |
JPS5451976A (en) | 1979-04-24 |
FR2404676A2 (en) | 1979-04-27 |
DE2756201B2 (en) | 1980-08-14 |
DE2756201A1 (en) | 1979-04-05 |
IT1155781B (en) | 1987-01-28 |
IT7847733A0 (en) | 1978-01-20 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |