CN103011179A - Method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas - Google Patents
Method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas Download PDFInfo
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- CN103011179A CN103011179A CN2013100097394A CN201310009739A CN103011179A CN 103011179 A CN103011179 A CN 103011179A CN 2013100097394 A CN2013100097394 A CN 2013100097394A CN 201310009739 A CN201310009739 A CN 201310009739A CN 103011179 A CN103011179 A CN 103011179A
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- Prior art keywords
- phosphoric acid
- wet
- flue gas
- ammonium fluoride
- process phosphoric
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- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 title claims abstract description 74
- 238000000034 method Methods 0.000 title claims abstract description 56
- 229910000147 aluminium phosphate Inorganic materials 0.000 title claims abstract description 37
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 31
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 26
- 239000003546 flue gas Substances 0.000 title claims abstract description 26
- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 14
- 239000010703 silicon Substances 0.000 title claims abstract description 14
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 title abstract description 13
- 238000004519 manufacturing process Methods 0.000 title abstract description 11
- LRCFXGAMWKDGLA-UHFFFAOYSA-N dioxosilane;hydrate Chemical compound O.O=[Si]=O LRCFXGAMWKDGLA-UHFFFAOYSA-N 0.000 title abstract description 4
- 238000010521 absorption reaction Methods 0.000 claims abstract description 23
- 239000007789 gas Substances 0.000 claims abstract description 21
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000007788 liquid Substances 0.000 claims abstract description 15
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910052731 fluorine Inorganic materials 0.000 claims abstract description 11
- 239000011737 fluorine Substances 0.000 claims abstract description 11
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000004140 cleaning Methods 0.000 claims abstract description 8
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims abstract description 6
- 239000013078 crystal Substances 0.000 claims abstract description 3
- LDDQLRUQCUTJBB-UHFFFAOYSA-N ammonium fluoride Chemical compound [NH4+].[F-] LDDQLRUQCUTJBB-UHFFFAOYSA-N 0.000 claims description 18
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 10
- 229910052757 nitrogen Inorganic materials 0.000 claims description 5
- 238000010924 continuous production Methods 0.000 claims description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 8
- 230000002745 absorbent Effects 0.000 abstract description 4
- 239000002250 absorbent Substances 0.000 abstract description 4
- 239000000741 silica gel Substances 0.000 abstract description 2
- 229910002027 silica gel Inorganic materials 0.000 abstract description 2
- ABTOQLMXBSRXSM-UHFFFAOYSA-N silicon tetrafluoride Chemical compound F[Si](F)(F)F ABTOQLMXBSRXSM-UHFFFAOYSA-N 0.000 abstract description 2
- 238000005406 washing Methods 0.000 abstract description 2
- 229910004014 SiF4 Inorganic materials 0.000 abstract 1
- 229910004072 SiFe Inorganic materials 0.000 abstract 1
- ZHPNWZCWUUJAJC-UHFFFAOYSA-N fluorosilicon Chemical compound [Si]F ZHPNWZCWUUJAJC-UHFFFAOYSA-N 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 4
- 238000001914 filtration Methods 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 229960001866 silicon dioxide Drugs 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- 239000011574 phosphorus Substances 0.000 description 2
- 229920001296 polysiloxane Polymers 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 102000004160 Phosphoric Monoester Hydrolases Human genes 0.000 description 1
- 108090000608 Phosphoric Monoester Hydrolases Proteins 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 239000002367 phosphate rock Substances 0.000 description 1
- 229960004029 silicic acid Drugs 0.000 description 1
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- Treating Waste Gases (AREA)
Abstract
The invention discloses a method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas, which comprises the following steps: preparing crystal ammonium fluoride into a 10-25% ammonium fluoride solution to be used as an SiFe gas absorbent for flue gas in wet-process phosphoric acid reaction; washing the wet-process phosphoric acid F-containing exhaust with the absorption liquid in a pump circulation mode; and finally, introducing gas ammonia into the ammonium fluosilicate solution generated by absorbing SiF4 gas by ammonium fluoride, thereby producing the silicon dioxide hydrate and ammonium fluoride. The method recovers fluorine and silicon resources in wet-process phosphoric acid reaction flue gas, so that the fluorine content in the phosphoric acid reaction flue gas is reduced from 10.5g/m<3> to 0.05g/m<3>, and the silicon content is reduced from 4.08g/m<3> to 0.02g/m<3>; and meanwhile, the method reduces the possibility of equipment pipeline blockage by silica gel, prolongs the production cycle of wet-process phosphoric acid from 7 days to 25 days, lowers the labor intensity for cleaning scales in the equipment pipeline, and enhances the operating ratio of the device.
Description
Technical field
The present invention relates to silicon-dioxide, furthermore, relate to and a kind ofly contain preparing hydrated silica dioxide method the flue gas from wet-process phosphoric acid reaction.
Background technology
As everyone knows, silicon is with SiF in the wet-process phosphoric acid reaction flue gas
4Form exist, the absorption technique of silicon-containing gas is to absorb by water in traditional wet-process phosphoric acid reaction flue gas, in the process that water absorbs, generates SiO
2, the SiO of generation
2Because foreign matter content is larger, can only stack as waste.And water absorbs SiF in the wet-process phosphoric acid reaction flue gas
4Generate SiO
2, the phosphate equipment pipeline scale stops up serious, not only affects the assimilation effect of fluorine in the wet-process phosphoric acid reaction flue gas, also because the equipment pipe fouling is serious, needs a large amount of manpower and materials to clear up, and has a strong impact on the driving rate of auto levelizer.
In relevant prior art, silicon mainly with the form of compound, extensively is present in silicate and the silica.Industrial, normally in electric furnace, made by carbon reduction silicon-dioxide, from phosphorus ore, reclaim silicon resource, there is no at present special production technique, but people are still developing recovery silicon resource technology from phosphorus ore with suiting measures to local conditions.
Summary of the invention
The object of the present invention is to provide a kind of method that reclaims the silicon production hydrated SiO 2 in the wet-process phosphoric acid reaction flue gas with Neutral ammonium fluoride, to reduce equipment pipe fouling in the Wet-process Phosphoric Acid Production process, to reduce the waste discharge in the Wet-process Phosphoric Acid Production process.
The contriver is through research and practice, and the method that provides may further comprise the steps:
It is 10～25% ammonium fluoride solution that the first step is mixed with mass percent with the crystal Neutral ammonium fluoride, as SiF in the wet-process phosphoric acid reaction flue gas
4The absorption agent of gas;
Second step contains F tail gas with absorption liquid with pump circulation cleaning phosphoric acid by wet process;
The 3rd step absorbed SiF with Neutral ammonium fluoride
4The ammonium fluosilicate solution of gas generation passes into gas ammonia, produces hydrated SiO 2 and Neutral ammonium fluoride.
The ammonium fluoride solution of 10～25% described in the first step of aforesaid method is 40-55 ℃ in temperature, and the pH value span of control of absorption liquid is 6-7.
Absorption liquid described in the second step of aforesaid method contains F tail gas with pump circulation cleaning phosphoric acid by wet process, and the ratio of the nitrogen in the absorption liquid and fluorine mass percent can be realized continuous production for being controlled at 3.5-4.5.
Described in the 3rd step of aforesaid method Neutral ammonium fluoride is absorbed SiF
4The ammonium fluosilicate solution of gas generation passes into gas ammonia gas, and temperature of reaction is controlled at 40-50 ℃, and the pH value span of control of reaction end is 8.7-9.2.
The contriver points out, ammonium fluoride solution with 10～25% reclaims the silicon tetrafluoride in the wet-process phosphoric acid reaction flue gas, not only solve vent gas washing system obstruction in the Wet-process Phosphoric Acid Production process, affect the problem of device operation, can also make changing waste into resources, the fluorine silicon resource that reclaims in the wet-process phosphoric acid reaction flue gas is produced hydrated SiO 2 and more Neutral ammonium fluoride.The fluorine silicon resource of producing in hydrated SiO 2 and the Neutral ammonium fluoride is provided by the wet-process phosphoric acid reaction flue gas, in the sour decomposing phosphate rock reaction process, produces a large amount of SiF
4Gas, the ammonium fluoride solution with 10～25% absorbs SiF
4Gas obtains 15～30% ammonium fluosilicate solution, ammonium fluosilicate solution again with ammonia react, obtain hydrated SiO 2 and Neutral ammonium fluoride, hydrated SiO 2 and Neutral ammonium fluoride can be used as merchandise sales.The silicone content of hydrated SiO 2 can reach greater than 90%.
The invention has the beneficial effects as follows: after adopting the inventive method, reclaimed fluorine silicon resource in the wet-process phosphoric acid reaction flue gas, made in the phosphatase reaction flue gas fluorine content from 10.5g/m
3Be reduced to 0.05g/m
3, silicone content is from 4.08g/m
3Be reduced to 0.02g/m
3Reduce simultaneously the silica gel blocking equipment pipe, prolonged the production cycle of phosphoric acid by wet process, can extend to 25 days by original 7 days, reduced the labour intensity of cleaning equipment pipeline scale, improved the operation ratio of device.
Embodiment
Below by embodiment, further specify beneficial effect of the present invention.
Certain factory adopts method of the present invention, and implementation is as follows:
Embodiment 1:With 1.2 tons of solid-state Neutral ammonium fluorides, be mixed with 10 tons in absorption agent first; Be mixed with Neutral ammonium fluoride absorbent solution, massfraction is that 12%, pH value is 6.0; Then with pump absorption liquid is squeezed into phosphoric acid by wet process tail cleaning device and circulate and absorb fluorine silicon gas in the wet-process phosphoric acid reaction flue gas, absorption temperature is controlled at 55 ℃; The ratio of nitrogen and fluorine mass percent passes into ammonia for being controlled at 3.5 o'clock in the absorption liquid, treats that pH reaches at 8.7 o'clock, obtains hydrated SiO 2 after filtering.
Embodiment 2:With 2.5 tons of solid-state Neutral ammonium fluorides, be mixed with 10 tons in absorption agent first; Be mixed with Neutral ammonium fluoride absorbent solution, massfraction is that 26%, pH value is 6.5; Then with pump absorption liquid is squeezed into phosphoric acid by wet process tail cleaning device and circulate and absorb fluorine silicon gas in the wet-process phosphoric acid reaction flue gas, absorption temperature is controlled at 45 ℃; The ratio of nitrogen and fluorine mass percent passes into ammonia for being controlled to be 4.0 in the absorption liquid, treats that pH reaches at 9.0 o'clock, obtains hydrated SiO 2 after filtering.
Embodiment 3:With 2.5 tons of solid-state Neutral ammonium fluorides, be mixed with 10 tons in absorption agent first; Be mixed with Neutral ammonium fluoride absorbent solution, massfraction is that 26%, pH value is 7.0; Then with pump absorption liquid is squeezed into phosphoric acid by wet process tail cleaning device and circulate and absorb fluorine silicon gas in the wet-process phosphoric acid reaction flue gas, absorption temperature is controlled at 40 ℃; The ratio of nitrogen and fluorine mass percent passes into ammonia for being controlled to be 3.5 in the absorption liquid, treats that pH reaches at 9.2 o'clock, obtains hydrated SiO 2 after filtering.
Adopt the method for above-mentioned 3 embodiment, the fluorine yield in the wet-process phosphoric acid reaction flue gas reaches 99.52%, and the silicon yield reaches 99.50%; 2194 ton/years in fluorine in the recovery Wet Method Reaction flue gas, 850 ton/years of the silicon in the recovery Wet Method Reaction flue gas; Prolonged the production cycle of phosphoric acid by wet process, the Wet Phosphoric Acid Plant stop frequency is dropped to 17 times/years from 48 times/years, device can improve 10 days every year working time, and production capacity improves 12000 ton/years.
The above, it only is preferred embodiment of the present invention, be not that the present invention is done any pro forma restriction, any technical solution of the present invention content that do not break away from,, all still belong in the scope of technical solution of the present invention any simple modification, equivalent variations and modification that above embodiment does according to technical spirit of the present invention.
Claims (4)
1. reclaim the method that the silicon in the wet-process phosphoric acid reaction flue gas is produced hydrated SiO 2, it is characterized in that it may further comprise the steps:
(1) the crystal Neutral ammonium fluoride being mixed with mass percent is 10～25% ammonium fluoride solution, as SiF in the wet-process phosphoric acid reaction flue gas
4The absorption liquid of gas;
(2) absorption liquid is contained F tail gas with pump circulation cleaning phosphoric acid by wet process;
(3) Neutral ammonium fluoride is absorbed SiF
4The ammonium fluosilicate solution of gas generation passes into gas ammonia, produces hydrated SiO 2 and Neutral ammonium fluoride.
2. method according to claim 1 is characterized in that in the described step (1), the temperature of ammonium fluoride solution is 40-55 ℃, and absorption liquid pH value span of control is 6-7.
3. method according to claim 1 is characterized in that in the described step (2), the ratio of the nitrogen in the absorption liquid and fluorine mass percent can be realized continuous production for being controlled at 3.5-4.5.
4. method according to claim 1 is characterized in that in the described step (3), temperature of reaction is controlled at 40-50 ℃, and the pH value span of control of reaction end is 8.7-9.2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013100097394A CN103011179A (en) | 2013-01-11 | 2013-01-11 | Method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013100097394A CN103011179A (en) | 2013-01-11 | 2013-01-11 | Method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas |
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| Publication Number | Publication Date |
|---|---|
| CN103011179A true CN103011179A (en) | 2013-04-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2013100097394A Pending CN103011179A (en) | 2013-01-11 | 2013-01-11 | Method for producing silicon dioxide hydrate from silicon recovered from wet-process phosphoric acid reaction flue gas |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103588209A (en) * | 2013-11-01 | 2014-02-19 | 青岛星火化工技术有限公司 | Method for recovery and comprehensive utilization of SiF4 gas |
| CN105585017A (en) * | 2016-03-09 | 2016-05-18 | 衢州市鼎盛化工科技有限公司 | Industrial production method for high-purity silicon dioxide |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4046860A (en) * | 1973-05-14 | 1977-09-06 | Kidde Gustave E | Ammonium fluoride process for defluorinating phosphoric acids and production of ammonium fluosilicate |
| CN1319561A (en) * | 2001-04-10 | 2001-10-31 | 夏克立 | Method for producing fluoride and silicon dioxide |
| CN1721044A (en) * | 2005-05-24 | 2006-01-18 | 夏克立 | Fluorine-containing waste gas utilization method in phosphorus fertilizer production |
-
2013
- 2013-01-11 CN CN2013100097394A patent/CN103011179A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4046860A (en) * | 1973-05-14 | 1977-09-06 | Kidde Gustave E | Ammonium fluoride process for defluorinating phosphoric acids and production of ammonium fluosilicate |
| CN1319561A (en) * | 2001-04-10 | 2001-10-31 | 夏克立 | Method for producing fluoride and silicon dioxide |
| CN1721044A (en) * | 2005-05-24 | 2006-01-18 | 夏克立 | Fluorine-containing waste gas utilization method in phosphorus fertilizer production |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103588209A (en) * | 2013-11-01 | 2014-02-19 | 青岛星火化工技术有限公司 | Method for recovery and comprehensive utilization of SiF4 gas |
| CN103588209B (en) * | 2013-11-01 | 2015-06-24 | 青岛星火化工技术有限公司 | Method for recovery and comprehensive utilization of SiF4 gas |
| CN105585017A (en) * | 2016-03-09 | 2016-05-18 | 衢州市鼎盛化工科技有限公司 | Industrial production method for high-purity silicon dioxide |
| CN105585017B (en) * | 2016-03-09 | 2017-12-15 | 衢州市鼎盛化工科技有限公司 | The industrialized preparing process of high-purity silicon dioxide |
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| PB01 | Publication | ||
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Application publication date: 20130403 |