WO1996027554A1 - Verfahren zur gewinnung bzw. rückgewinnung von säuren - Google Patents
Verfahren zur gewinnung bzw. rückgewinnung von säuren Download PDFInfo
- Publication number
- WO1996027554A1 WO1996027554A1 PCT/AT1996/000042 AT9600042W WO9627554A1 WO 1996027554 A1 WO1996027554 A1 WO 1996027554A1 AT 9600042 W AT9600042 W AT 9600042W WO 9627554 A1 WO9627554 A1 WO 9627554A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- metal
- rust
- nitric acid
- evaporation
- gases
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/20—Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
- C01B21/38—Nitric acid
- C01B21/46—Purification; Separation ; Stabilisation
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/14—Methods for preparing oxides or hydroxides in general
- C01B13/34—Methods for preparing oxides or hydroxides in general by oxidation or hydrolysis of sprayed or atomised solutions
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
- C01B7/191—Hydrogen fluoride
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/36—Regeneration of waste pickling liquors
Definitions
- the invention relates to a process for the recovery or recovery of acids, in particular hydrofluoric acid and nitric acid, from metal-containing solutions.
- Metal-containing solutions which contain hydrofluoric acid and nitric acid, fall in particular in the metal industry as nitric acid mixed acid pickling in the surface treatment of stainless steels.
- Special alloys and special metals They contain free hydrofluoric acid, free nitric acid and iron dissolved as fluoride. Chrome and nickel.
- nitric acid is particularly important at temperatures above 200 ° C
- oxygen or other oxidizing agents such as hydrogen peroxide to NO 2 .
- the recovery rates achievable according to this process are unsatisfactory. It is described that a maximum recovery rate of 33% of the nitric acid originally used is possible in one column. Only through additional oxidation measures. which naturally entails increased chemical expenditure and thus higher costs, a recovery rate of approx. 40% can be achieved in the second column.
- the total amount of nitric acid recoverable from the metal-containing solution is a maximum of about 80% of the amount used when additional oxidation measures are used, the rest of the unreacted nitrogen oxides must be separated from the rust gases, e.g. in DeNOx systems, and is no longer available for the recovery of nitric acid
- This task is solved according to the invention in that the metal-containing solution is evaporated at temperatures at which essentially no decomposition of the nitric acid takes place, that the metal-containing residue of the evaporation is treated pyrohydrolytically, the metal fluids being converted into metal oxides, and in that the resulting rust gases are separated from the rust gases
- hydrofluoric acid and nitric acid can be separated from the metal-containing solutions by the sequence of process steps hydrofluoric acid and nitric acid with jerk rates of up to 90% and above, without having to resort to additional measures for oxidation or intensive cooling
- the invention is based on the knowledge of removing a large part of the nitric acid in the metal-containing solution from the solution by evaporation below the decomposition temperature of the nitric acid.
- the small amount of nitric acid remaining in the metal-containing residue is indeed partially decomposed in the reactor as described in the beginning, but this is The extent of the resulting nitric acid losses is so small that additional oxidation of the nitrogen oxides formed and conversion to nitric acid can be completely avoided
- the evaporation of the metal-containing solution preferably takes place at temperatures below 200 ° C. and particularly advantageously in a temperature range from 80 to 120 ° C. it is ensured that no significant decomposition of the nitric acid takes place during evaporation
- the evaporation is carried out at reduced pressure. This enables a gentler treatment of the metal-containing solution
- the preliminary treatment of the metal-containing residue is preferably carried out in a spray rust reactor
- the process according to the invention can be carried out even more efficiently if the temperature in the burner reactor is 500 to 700.degree. C., preferably 550 to 650.degree. C. At these higher temperatures, the pyrohvdrolysis reactions take place more quickly due to the fact that If only small amounts of nitric acid get into the spray rust reactor at all, the decomposition of the nitric acid, which also occurs more strongly at these higher temperatures, is of little importance
- the rust gases are preferably passed through at least one absorption column to separate the acids present in the rust gases
- the temperature in the absorption column is preferably kept above 70.degree. C., which means that essentially no cooling is carried out. This is not necessary because no measures are taken according to the invention to recover from the decomposition products which are likewise present in the rust gases in small quantities To gain nitric acid
- part of the acidic solution emerging from the absorption column is circulated over the column
- washing liquid accumulates more and more with absorbed acids and thus higher concentrations of hydrofluoric and nitric acids can be achieved
- the metal-containing residue of evaporation with absorption liquid is dissolved or diluted from at least one of the absorption columns used
- Particularly suitable as a liquid for dissolving or diluting the metal-containing residue is washing liquid from a second or third absorption column, in which no significant acid concentrations occur anymore. In this way, even slightly acidic wastewater can be recycled in a cycle
- a metal-containing solution (1) is obtained.
- the evaporator (002) is preferably a single-stage or multi-stage vacuum evaporator, in which the evaporation is carried out under reduced pressure, for example under pressure reduction to 0.5 bar, in one-stage systems.
- the evaporation residue (3) can be dissolved or diluted in fresh water or preferably with the outlet (5) of an absorption column (012).
- the main part of the evaporation residue contains metal fluorides as well as small amounts of metal nitrates and residues of non-evaporated nitric acid.
- This diluted evaporation residue (6) is then conveyed into a reactor for pyrohvdrolviischen treatment, preferably a spray rust reactor (007).
- the diluted evaporation residue (6) preferably passes through a flue gas scrubber (006) in which it comes into contact with roasting gases (8) from the spray roasting reactor (007) and is partially evaporated.
- a part of the evaporation residue (6) can advantageously be circulated through the flue gas scrubber (006).
- the resulting metal oxides (9) are continuously drawn off at the lower end ) in the flue gas scrubber (006). where they are also cooled by the diluted evaporation residue (6) from the container (005). At this point the decomposition reactions of the nitric acid are stopped due to the reversal of the equilibrium position of the reaction
- the cleaned rust gases (15) pass from the flue gas scrubber (006) into a first absorption column Kl (01 1), the acids in the rust gases (15) being absorbed with water.
- part ( 16) the mixed acid regenerated in this way is circulated over the absorption column Kl (01 1).
- the rest (12) of the regenerated mixed acid from the column Kl (011) is pumped to the mixed acid storage tank (004)
- the outflow from column K 1 (01 1) is cooled to just above 70 ° C. by means of cooling means (016)
- the second absorption column K2 (012). which is also fed with water, serves primarily as an exhaust gas scrubber.A part of the washing liquid (5) created here can be used to dissolve or dilute the metal-containing evaporation residue. Part of the washing liquid can also be circulated in the column K2 (012)
- the waste gases (13) still present after the second wash column (012) are in an alkaline scrubber W 1 (013). preferably freed from the last traces of acid using NaOH or other alkaline reagents and passed to a DeNOx plant (014) for the catalytic reduction of NOx with ammonia or urea
- the exhaust gases (14) freed from acids and nitrogen oxides in this way are discharged into the atmosphere by an exhaust gas fan (015).
- the exhaust gas fan (015) naturally also effects the entire gas transport through the plant, starting with the extraction of the roasting gases (10) from the reactor (007) up to the pushing out of the cleaned exhaust gases (14) through the chimney (014).
- the sum of Fe is the sum of the metals Fe. Ni and Cr understood, the majority of Fe being formed.
- This pickling agent (1) was evaporated in batches in a vacuum evaporator at a pressure between 200 and 500 mbar and at temperatures between 80 and 90 ° C. This gave a metal-containing concentrate (3) with the following composition:
- the evaporation residue, i.e. H. the metal-containing concentrate (3). was rinsed from the evaporator (002) with water into the stirred tank (005) and dissolved there with further addition of water while stirring, resulting in 380 1 low-acid, metal-containing solution (6) with the following composition:
- This reactor was heated with 7 m ' h of natural gas and 85 m7 h of air, a temperature of about 550 ° C. being established in the burner level.
- the partial stream (1 1) of the pickling agent (6) was fed into the reactor head in an amount of 75 1 Ti injected
- roasting gases (10) were sucked out of the reactor (007) by the negative pressure of the fan (15) and passed through the rust gas line (008) first into the dust separator (009) and then into the flue gas scrubber (006).
- This enriched rust gas reaches the first absorption column (01 1), where the absorption of the HNO 3 . HF and part of the NO: component in the NO according to the equation 3 NO ⁇ - H - »2 HNO * NO
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96903826A EP0759011A1 (de) | 1995-03-07 | 1996-03-06 | Verfahren zur gewinnung bzw. rückgewinnung von säuren |
KR1019960706291A KR970702819A (ko) | 1995-03-07 | 1996-11-07 | 산을 추출하거나 회수하기 위한 방법(process for extracting or recovering acids) |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ATA395/95 | 1995-03-07 | ||
AT0039595A AT412001B (de) | 1995-03-07 | 1995-03-07 | Verfahren zur gewinnung bzw. rückgewinnung von säuren |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996027554A1 true WO1996027554A1 (de) | 1996-09-12 |
Family
ID=3489470
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/AT1996/000042 WO1996027554A1 (de) | 1995-03-07 | 1996-03-06 | Verfahren zur gewinnung bzw. rückgewinnung von säuren |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0759011A1 (de) |
KR (1) | KR970702819A (de) |
AT (1) | AT412001B (de) |
WO (1) | WO1996027554A1 (de) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0843025A1 (de) * | 1996-11-15 | 1998-05-20 | Keramchemie GmbH | Verfahren zur Regenerierung einer verbrauchten Beizlösung |
EP0984078A1 (de) * | 1998-09-03 | 2000-03-08 | Eurox Eisenoxydproduktions- und Vertriebsgesellschaft m.b.H. | Verfahren zur Gewinnung bzw. Rückgewinnung von Flusssäure und Salpetersäure |
EP1038991A1 (de) * | 1999-03-22 | 2000-09-27 | Andritz-Patentverwaltungs-Gesellschaft m.b.H. | Verfahren zur Rückgewinnung von Säuren aus metallhaltigen Lösungen dieser Säuren |
WO2002038819A2 (en) * | 2000-11-08 | 2002-05-16 | Hatch Associates Ltd. | Process for regeneration of spent acid halide leach solutions |
EP1253112A1 (de) * | 2001-04-25 | 2002-10-30 | Andritz AG | Verfahren und Vorrichtung zur Gewinnung von Metalloxiden |
WO2004007801A1 (de) * | 2002-07-10 | 2004-01-22 | Uvk Engineering Gmbh | Verfahren und vorrichtung zum recyceln von metall-beizbädern |
EP1310581A3 (de) * | 2001-11-07 | 2004-10-20 | Andritz AG | Verfahren zur Behandlung säure- und metallhaltiger Abwässer |
WO2006025077A1 (en) * | 2004-09-03 | 2006-03-09 | Centro Studi E Ricerche S.R.L. | Treatment method of an exhausted pickling bath |
WO2011130760A1 (de) * | 2010-04-20 | 2011-10-27 | Key Technologies Industriebau Gmbh | Verfahren zur gewinnung bzw. rückgewinnung von salpetersäure und flusssäure aus lösungen von edelstahlbeizanlagen |
WO2015132118A1 (de) * | 2014-03-04 | 2015-09-11 | Leonhartsberger Michael | Vorrichtung zur aufbereitung von metallionenhältigen lösungen |
CN107601605A (zh) * | 2017-10-20 | 2018-01-19 | 鞍山创新废酸除硅再生工程有限公司 | 一种提高不锈钢酸洗废液再生硝酸收率的工艺及系统 |
AT522593A4 (de) * | 2019-09-24 | 2020-12-15 | Sustec Gmbh | Rückgewinnung von Säuren und Metallen aus trockenen Salzverbindungen |
AT522594B1 (de) * | 2019-09-03 | 2020-12-15 | Umwandlung von Metallsaizösungen in flüssige Säuren und feste Metalloxide |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1311757A (en) * | 1970-05-19 | 1973-03-28 | Sued Chemie Ag | Hydrogen halide production |
AT374508B (de) * | 1982-07-01 | 1984-05-10 | Ruthner Industrieanlagen Ag | Verfahren zur aufarbeitung verbrauchter beizoder aetzloesungen auf der basis von salpeter-flussaeure |
GB2134095A (en) * | 1983-01-25 | 1984-08-08 | Outokumpu Oy | Method for regenerating pickling acids |
EP0296147A1 (de) * | 1987-06-16 | 1988-12-21 | Maschinenfabrik Andritz Aktiengesellschaft | Verfahren zur Gewinnung bzw. Rückgewinnung von Säuren aus metallhaltigen Lösungen dieser Säuren |
WO1993010038A1 (en) * | 1991-11-22 | 1993-05-27 | Technological Resources Pty Limited | Regeneration of hydrochloric acid |
DE4315551A1 (de) * | 1993-05-10 | 1994-11-17 | Gewerk Keramchemie | Verfahren zur Regenerierung von verbrauchten, Metallsalze und/oder Metalloxide enthaltenden Lösungen, insbesondere Milchsäuren |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT335251B (de) * | 1975-03-10 | 1977-03-10 | Ruthner Industrieanlagen Ag | Verfahren und vorrichtung zur wiedergewinnung von salpetersaure und flusssaure aus losungen |
US4252602A (en) * | 1978-10-04 | 1981-02-24 | Ruthner Industrieanlagen-Aktiengesellschaft | Apparatus for recovering nitric acid and hydrofluoric acid from solutions |
AT376632B (de) * | 1979-06-15 | 1984-12-10 | Ruthner Industrieanlagen Ag | Verfahren und anlage zur gewinnung bzw. rueckgewinnung von flussaeure |
-
1995
- 1995-03-07 AT AT0039595A patent/AT412001B/de not_active IP Right Cessation
-
1996
- 1996-03-06 EP EP96903826A patent/EP0759011A1/de not_active Withdrawn
- 1996-03-06 WO PCT/AT1996/000042 patent/WO1996027554A1/de not_active Application Discontinuation
- 1996-11-07 KR KR1019960706291A patent/KR970702819A/ko not_active Application Discontinuation
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1311757A (en) * | 1970-05-19 | 1973-03-28 | Sued Chemie Ag | Hydrogen halide production |
AT374508B (de) * | 1982-07-01 | 1984-05-10 | Ruthner Industrieanlagen Ag | Verfahren zur aufarbeitung verbrauchter beizoder aetzloesungen auf der basis von salpeter-flussaeure |
GB2134095A (en) * | 1983-01-25 | 1984-08-08 | Outokumpu Oy | Method for regenerating pickling acids |
EP0296147A1 (de) * | 1987-06-16 | 1988-12-21 | Maschinenfabrik Andritz Aktiengesellschaft | Verfahren zur Gewinnung bzw. Rückgewinnung von Säuren aus metallhaltigen Lösungen dieser Säuren |
WO1993010038A1 (en) * | 1991-11-22 | 1993-05-27 | Technological Resources Pty Limited | Regeneration of hydrochloric acid |
DE4315551A1 (de) * | 1993-05-10 | 1994-11-17 | Gewerk Keramchemie | Verfahren zur Regenerierung von verbrauchten, Metallsalze und/oder Metalloxide enthaltenden Lösungen, insbesondere Milchsäuren |
Non-Patent Citations (2)
Title |
---|
CHEMICAL ABSTRACTS, vol. 105, no. 16, 20 October 1986, Columbus, Ohio, US; abstract no. 136375, V. P. UL'YANOV ET AL.: "Waste-free thermal regeneration of sulfuric acid and nitric-hydrofluoric acid pickling solutions" XP002004082 * |
STAL', vol. 5, 1986, USSR, pages 102 - 105 * |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0843025A1 (de) * | 1996-11-15 | 1998-05-20 | Keramchemie GmbH | Verfahren zur Regenerierung einer verbrauchten Beizlösung |
EP0984078A1 (de) * | 1998-09-03 | 2000-03-08 | Eurox Eisenoxydproduktions- und Vertriebsgesellschaft m.b.H. | Verfahren zur Gewinnung bzw. Rückgewinnung von Flusssäure und Salpetersäure |
EP1038991A1 (de) * | 1999-03-22 | 2000-09-27 | Andritz-Patentverwaltungs-Gesellschaft m.b.H. | Verfahren zur Rückgewinnung von Säuren aus metallhaltigen Lösungen dieser Säuren |
WO2002038819A2 (en) * | 2000-11-08 | 2002-05-16 | Hatch Associates Ltd. | Process for regeneration of spent acid halide leach solutions |
WO2002038819A3 (en) * | 2000-11-08 | 2002-09-26 | Hatch Ass Ltd | Process for regeneration of spent acid halide leach solutions |
US6692719B1 (en) | 2000-11-08 | 2004-02-17 | Hatch Ltd. | Process for regeneration of acid halide solutions |
EP1253112A1 (de) * | 2001-04-25 | 2002-10-30 | Andritz AG | Verfahren und Vorrichtung zur Gewinnung von Metalloxiden |
US7597873B2 (en) | 2001-04-25 | 2009-10-06 | Andritz Ag | Process and apparatus for the recovery of metal oxide particles |
AT413697B (de) * | 2001-11-07 | 2006-05-15 | Andritz Ag Maschf | Verfahren zur behandlung säurehältiger abwässer |
EP1310581A3 (de) * | 2001-11-07 | 2004-10-20 | Andritz AG | Verfahren zur Behandlung säure- und metallhaltiger Abwässer |
DE10231308C5 (de) * | 2002-07-10 | 2009-10-15 | Cmi Uvk Gmbh | Verfahren und Vorrichtung zum Recyceln von Edelstahl-Beizbädern |
US9139916B2 (en) | 2002-07-10 | 2015-09-22 | Cmi Uvk Gmbh | Method and device for recycling metal pickling baths |
WO2004007801A1 (de) * | 2002-07-10 | 2004-01-22 | Uvk Engineering Gmbh | Verfahren und vorrichtung zum recyceln von metall-beizbädern |
WO2006025077A1 (en) * | 2004-09-03 | 2006-03-09 | Centro Studi E Ricerche S.R.L. | Treatment method of an exhausted pickling bath |
CN102892928B (zh) * | 2010-04-20 | 2015-11-25 | 关键技术工业有限公司 | 从不锈钢酸洗设备的溶液中获得或回收硝酸和氢氟酸的方法 |
CN102892928A (zh) * | 2010-04-20 | 2013-01-23 | 关键技术工业有限公司 | 从不锈钢酸洗设备的溶液中获得或回收硝酸和氢氟酸的方法 |
WO2011130760A1 (de) * | 2010-04-20 | 2011-10-27 | Key Technologies Industriebau Gmbh | Verfahren zur gewinnung bzw. rückgewinnung von salpetersäure und flusssäure aus lösungen von edelstahlbeizanlagen |
WO2015132118A1 (de) * | 2014-03-04 | 2015-09-11 | Leonhartsberger Michael | Vorrichtung zur aufbereitung von metallionenhältigen lösungen |
CN107601605A (zh) * | 2017-10-20 | 2018-01-19 | 鞍山创新废酸除硅再生工程有限公司 | 一种提高不锈钢酸洗废液再生硝酸收率的工艺及系统 |
CN107601605B (zh) * | 2017-10-20 | 2023-05-09 | 鞍山创鑫环保科技股份有限公司 | 一种提高不锈钢酸洗废液再生硝酸收率的工艺及系统 |
AT522594B1 (de) * | 2019-09-03 | 2020-12-15 | Umwandlung von Metallsaizösungen in flüssige Säuren und feste Metalloxide | |
AT522594A4 (de) * | 2019-09-03 | 2020-12-15 | Umwandlung von Metallsalziösungen in flüssige Säuren und feste Metalloxide | |
AT522593A4 (de) * | 2019-09-24 | 2020-12-15 | Sustec Gmbh | Rückgewinnung von Säuren und Metallen aus trockenen Salzverbindungen |
AT522593B1 (de) * | 2019-09-24 | 2020-12-15 | Sustec Gmbh | Rückgewinnung von Säuren und Metallen aus trockenen Salzverbindungen |
Also Published As
Publication number | Publication date |
---|---|
EP0759011A1 (de) | 1997-02-26 |
KR970702819A (ko) | 1997-06-10 |
AT412001B (de) | 2004-08-26 |
ATA39595A (de) | 1997-03-15 |
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