CH613917A5 - Process for purifying waste water or for treating water - Google Patents
Process for purifying waste water or for treating waterInfo
- Publication number
- CH613917A5 CH613917A5 CH748475A CH748475A CH613917A5 CH 613917 A5 CH613917 A5 CH 613917A5 CH 748475 A CH748475 A CH 748475A CH 748475 A CH748475 A CH 748475A CH 613917 A5 CH613917 A5 CH 613917A5
- Authority
- CH
- Switzerland
- Prior art keywords
- water
- flocculants
- stage
- salts
- inorganic
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 24
- 239000002351 wastewater Substances 0.000 title claims abstract description 6
- 230000008569 process Effects 0.000 title claims abstract description 4
- 239000008394 flocculating agent Substances 0.000 claims abstract description 19
- 239000007800 oxidant agent Substances 0.000 claims abstract description 17
- 239000010865 sewage Substances 0.000 claims abstract description 11
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical class [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 claims abstract description 7
- 238000003287 bathing Methods 0.000 claims abstract description 5
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 12
- 238000007792 addition Methods 0.000 claims description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 10
- 239000010802 sludge Substances 0.000 claims description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 8
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 8
- 239000000460 chlorine Substances 0.000 claims description 8
- 229910052801 chlorine Inorganic materials 0.000 claims description 8
- 238000005352 clarification Methods 0.000 claims description 8
- 230000006872 improvement Effects 0.000 claims description 8
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 claims description 6
- 238000000746 purification Methods 0.000 claims description 6
- 238000012360 testing method Methods 0.000 claims description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 4
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 4
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 4
- 239000000920 calcium hydroxide Substances 0.000 claims description 4
- 230000015556 catabolic process Effects 0.000 claims description 4
- 150000001875 compounds Chemical class 0.000 claims description 4
- 238000006731 degradation reaction Methods 0.000 claims description 4
- 230000035622 drinking Effects 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 239000001301 oxygen Substances 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- JRKICGRDRMAZLK-UHFFFAOYSA-L peroxydisulfate Chemical compound [O-]S(=O)(=O)OOS([O-])(=O)=O JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 claims description 4
- 239000012286 potassium permanganate Substances 0.000 claims description 4
- 238000001556 precipitation Methods 0.000 claims description 4
- MWNQXXOSWHCCOZ-UHFFFAOYSA-L sodium;oxido carbonate Chemical compound [Na+].[O-]OC([O-])=O MWNQXXOSWHCCOZ-UHFFFAOYSA-L 0.000 claims description 4
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 2
- 230000009471 action Effects 0.000 claims description 2
- 238000010564 aerobic fermentation Methods 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 230000029087 digestion Effects 0.000 claims description 2
- 238000002474 experimental method Methods 0.000 claims description 2
- 238000000855 fermentation Methods 0.000 claims description 2
- 239000007789 gas Substances 0.000 claims description 2
- 238000012812 general test Methods 0.000 claims description 2
- 239000011521 glass Substances 0.000 claims description 2
- 230000003993 interaction Effects 0.000 claims description 2
- FBAFATDZDUQKNH-UHFFFAOYSA-M iron chloride Chemical compound [Cl-].[Fe] FBAFATDZDUQKNH-UHFFFAOYSA-M 0.000 claims description 2
- 159000000014 iron salts Chemical class 0.000 claims description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 2
- 238000009533 lab test Methods 0.000 claims description 2
- 238000000247 postprecipitation Methods 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims description 2
- 239000004576 sand Substances 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- 239000002352 surface water Substances 0.000 claims description 2
- 230000002195 synergetic effect Effects 0.000 claims description 2
- 230000008719 thickening Effects 0.000 claims description 2
- 238000004065 wastewater treatment Methods 0.000 claims description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical class [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 abstract 1
- 239000003651 drinking water Substances 0.000 abstract 1
- 235000020188 drinking water Nutrition 0.000 abstract 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Water Treatment By Sorption (AREA)
Abstract
For purifying waste water and for treating water to produce drinking water, utility water, or bathing water, inorganic Fe(II) salts and/or Fe(III) salts are used as flocculants in combination with inorganic oxidising agents. The process according to the invention can be used in all stages of a sewage treatment plant.
Description
PATENTANSPRÜCHE
1. Verfahren zur Reinigung von Abwasser oder zur Aufbereitung von Wasser durch Behandlung mit Flockungsmitteln, dadurch gekennzeichnet, dass als Flockungsmittel anorganische Fe(II)- und/oder Fe(III)-Salze in Kombination mit anorganischen Oxidationsmitteln eingesetzt werden.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass als Oxidationsmittel Wasserstoffperoxid, Percarbonat oder Persulfat eingesetzt wird.
3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass als Oxidationsmittel Chlor oder Chlor abgebende Verbindungen eingesetzt werden.
4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass zusätzlich Calciumhydroxid oder Aluminiumsulfat eingesetzt wird.
5. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass zusätzlich Aktivkohle eingesetzt wird.
6. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass neben den Fe-Salzen auch organische Flockungsmittel eingesetzt werden.
7. Verfahren nach Anspruch 1 zur Herstellung von Trink-, Brauch- oder Badewasser.
8. Anwendung des Verfahrens nach Anspruch 1 in einer, mehreren oder allen Stufen einer Kläranlage.
9. Anwendung gemäss Anspruch 8 in der Vorfällung.
10. Anwendung gemäss Anspruch 8 in der Belebtschlammstufe.
11. Anwendung gemäss Anspruch 8 in der Nachklärstufe.
12. Anwendung gemäss Anspruch 8 in einer Nachfällung nach der Nachklärstufe;
Die vorliegende Erfindung betrifft ein Verfahren zur Reinigung von Abwasser oder zur Aufbereitung von Wasser durch Behandlung mit Flockungsmitteln, das dadurch gekennzeichnet ist, dass als Flockungsmittel anorganische Fe(II)- und/ oder Fe(III)-Salze in Kombination mit anorganischen Oxidationsmitteln eingesetzt werden.
Bisher wurde in der Abwasserreinigung hauptsächlich Eisenchlorid oder Aluminiumsulfat als Flockungsmittel verwendet.
Es wurde nun festgestellt, dass bei der Verwendung von anorganischen Flockungsmitteln in vielen Fällen durch Zusatz von Oxidationsmitteln, wie z. B. Wasserstoffperoxid, Percarbonat oder Persulfat, die Reinigung des Wassers stark verbessert wird. Die erhöhte Wirksamkeit beruht im Falle der Fe(II)und Fe(III)-Salze in Kombination mit Oxidationsmitteln auf einer Interaktion Oxidationsmittel - Fe III - Fe II - Ion. Für die Wasserreinigungseigenschaften ergibt sich dadurch eine synergistische Wirkung, wie das Beispiel der Permanganatzahl (Versuche 1 und 2) zeigt. Die Verbesserung ist jedoch nicht auf die Permanganatzahl beschränkt, sondern erstreckt sich auch auf weitere Eigenschaften wie die BSB5-Zahl (Biologischer Sauerstoffbedarf) oder CSB (Chemischer Sauerstoffbedarf [ engl. CODE) usw.
Als Oxidationsmittel können auch Chlor oder Chlor abgebende Verbindungen eingesetzt werden.
Das erfindungsgemässe Verfahren kann ebenso in Kombination mit Calziumhydroxid oder Aluminiumsulfat durchgeführt werden. Auch ein Zusatz von Aktivkohle im erfindungsgemässen Verfahren kann sich für die Wasserreinigung eignen.
Neben den Eisensalzen können als Flockungsmittel zusätzlich auch noch organische Flockungsmittel verwendet werden.
Diese Verbesserungen können insbesondere bei der Anwendung des erfindungsgemässen Verfahrens in Kläranlagen beobachtet werden. Ein weiterer Aspekt der vorliegenden Erfindung ist deshalb die Anwendung des erfindungsgemässen Verfahrens in einer, mehreren oder allen Stufen einer Kläranlage. Es kann sowohl in der Vorfällung, in der Belebtschlammstufe, in der Nachklärstufe als auch in einer eigenen, auf die Nachklärstufe folgenden Stufe angewendet werden.
In der Belebtschlammstufe wird insbesondere auch noch die aerobe Gärung begünstigt. Das erfindungsgemässe Verfahren kann auch, indem es die anaerobe Gärung im Faulturm beeinflusst, zur Schlammbehandlung bzw. -eindickung verwendet werden, wo es zur Erhöhung des Trockensubstanzgehaltes (wesentlicher Kostenfaktor bei der Abfuhr des Schlammes) und zur Geruchsbeeinflussung beiträgt. Es resultiert dabei insbesondere auch eine Verbesserung der Faulgasqualität.
Insgesamt kann die Anwendung des erfindungsgemässen Verfahrens eine wesentliche Durchsatzerhöhung einer Kläranlage bewirken.
Das erfindungsgemässe Verfahren kann auch zur Herstellung von Trink-, Brauch- oder Badewasser verwendet werden.
Das folgende Beispiel illustriert anhand der Permanganatzahl eine Verbesserung durch das erfindungsgemässe Verfahren.
Beispiel
Einfluss von Eisen-III-chlorid und Wasserstoffperoxid auf die Permanganatzahl von belastetem Wasser
Allg. Versuchsbedingungen (Laborversuche) - Reaktionsbehälter aus Glas, System geschlossen.
- Temperatur ca. 20 C.
- Diffuses Licht.
- Einwirkungsdauer 1/2-1 Tag.
- Zugabe diskontinuierlich, unterteilt in 10 gleiche Portionen während der Versuchsdauer.
Analysen
Bestimmung der Permanganatzahl nach den Eidg. Richtlinien (Angabe in mg KMnO4/l).
Versuch 1
Mit Rohwasser aus Kläranlage, nach Sandfang Vers. Zusätze Versuchs- Permanganatzahl
Fe3+ H202 dauer in mg Abbau in mg/l mg/l Tagen KMnO4/l % a) kein Zusatz 1 145 b) 10 0 1 120 17 c) 0 20 1 133 8 d) 10 20 1 99 32
Versuch 2
Mit Oberflächenwasser/Flusswasser Vers. Zusätze Versuchs- Permanganatzahl
Fe3+ H202 dauer in mg Abbau in rng/l mg/l Tagen Kino4/1 % a) kein Zusatz 0,5 10,9 b) 5 0 0,5 10,2 6 c) 0 3 0,5 9,8 10 d) 5 3 0,5 8,5 22
**WARNUNG** Ende DESC Feld konnte Anfang CLMS uberlappen**.
PATENT CLAIMS
1. A method for purifying wastewater or for treating water by treatment with flocculants, characterized in that inorganic Fe (II) and / or Fe (III) salts in combination with inorganic oxidizing agents are used as flocculants.
2. The method according to claim 1, characterized in that hydrogen peroxide, percarbonate or persulfate is used as the oxidizing agent.
3. The method according to claim 1, characterized in that chlorine or chlorine-releasing compounds are used as the oxidizing agent.
4. The method according to claim 1, characterized in that calcium hydroxide or aluminum sulfate is also used.
5. The method according to claim 1, characterized in that activated carbon is also used.
6. The method according to claim 1, characterized in that in addition to the Fe salts, organic flocculants are also used.
7. The method according to claim 1 for the production of drinking, industrial or bathing water.
8. Application of the method according to claim 1 in one, several or all stages of a sewage treatment plant.
9. Use according to claim 8 in the pre-precipitation.
10. Use according to claim 8 in the activated sludge stage.
11. Use according to claim 8 in the final clarification stage.
12. Use according to claim 8 in a post-precipitation after the final clarification stage;
The present invention relates to a method for purifying wastewater or for treating water by treatment with flocculants, which is characterized in that inorganic Fe (II) and / or Fe (III) salts in combination with inorganic oxidizing agents are used as flocculants .
Up to now, iron chloride or aluminum sulfate have mainly been used as flocculants in wastewater treatment.
It has now been found that when using inorganic flocculants in many cases by adding oxidizing agents, such as. B. hydrogen peroxide, percarbonate or persulfate, the purification of the water is greatly improved. In the case of the Fe (II) and Fe (III) salts in combination with oxidizing agents, the increased effectiveness is based on an interaction oxidizing agent - Fe III - Fe II - ion. This results in a synergistic effect for the water purification properties, as the example of the permanganate number (tests 1 and 2) shows. The improvement is not limited to the permanganate number, but also extends to other properties such as the BOD5 number (biological oxygen demand) or COD (chemical oxygen demand [CODE) etc.
Chlorine or chlorine-releasing compounds can also be used as oxidizing agents.
The method according to the invention can also be carried out in combination with calcium hydroxide or aluminum sulfate. The addition of activated carbon in the process according to the invention can also be suitable for water purification.
In addition to the iron salts, organic flocculants can also be used as flocculants.
These improvements can be observed in particular when the method according to the invention is used in sewage treatment plants. A further aspect of the present invention is therefore the use of the method according to the invention in one, several or all stages of a sewage treatment plant. It can be used both in the pre-precipitation, in the activated sludge stage, in the secondary clarification stage and in a separate stage following the secondary clarification stage.
In the activated sludge stage, aerobic fermentation is particularly favored. By influencing the anaerobic fermentation in the digestion tower, the method according to the invention can also be used for sludge treatment or thickening, where it contributes to increasing the dry matter content (a significant cost factor in the removal of the sludge) and influencing odor. In particular, this also results in an improvement in the quality of the digester gas.
Overall, the use of the method according to the invention can bring about a substantial increase in the throughput of a sewage treatment plant.
The method according to the invention can also be used for the production of drinking, industrial or bathing water.
The following example uses the permanganate number to illustrate an improvement made by the method according to the invention.
example
Influence of ferric chloride and hydrogen peroxide on the permanganate number of contaminated water
General Test conditions (laboratory tests) - reaction vessel made of glass, system closed.
- temperature approx. 20 C.
- Diffuse light.
- Duration of action 1 / 2-1 day.
- Adding discontinuously, divided into 10 equal portions during the duration of the experiment.
Analyzes
Determination of the permanganate number according to the federal guidelines (specification in mg KMnO4 / l).
Attempt 1
With raw water from sewage treatment plant, according to sand trap Vers. Additions test permanganate number
Fe3 + H202 duration in mg degradation in mg / l mg / l days KMnO4 / l% a) no addition 1 145 b) 10 0 1 120 17 c) 0 20 1 133 8 d) 10 20 1 99 32
Attempt 2
With surface water / river water Vers. Additions test permanganate number
Fe3 + H202 duration in mg degradation in rng / l mg / l days cinema4 / 1% a) no addition 0.5 10.9 b) 5 0 0.5 10.2 6 c) 0 3 0.5 9.8 10 d) 5 3 0.5 8.5 22
** WARNING ** End of DESC field could overlap beginning of CLMS **.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH748475A CH613917A5 (en) | 1975-06-10 | 1975-06-10 | Process for purifying waste water or for treating water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH748475A CH613917A5 (en) | 1975-06-10 | 1975-06-10 | Process for purifying waste water or for treating water |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH613917A5 true CH613917A5 (en) | 1979-10-31 |
Family
ID=4325841
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH748475A CH613917A5 (en) | 1975-06-10 | 1975-06-10 | Process for purifying waste water or for treating water |
Country Status (1)
| Country | Link |
|---|---|
| CH (1) | CH613917A5 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4402851A (en) | 1981-01-13 | 1983-09-06 | Boliden Aktiebolag | Pumpable composition for water-purifying purpose containing iron (II) sulphate, and a method for producing the same |
| DE3832523C1 (en) * | 1988-09-24 | 1990-01-18 | Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe, De | |
| DE3932174A1 (en) * | 1989-09-27 | 1991-04-11 | Degussa | METHOD FOR REDUCING THE AOX CONTENT IN WATER |
| DE4026831A1 (en) * | 1990-08-24 | 1992-02-27 | Inventa Ag | Catalytic oxidn. of organic components in waste water at low temp. - using hydrogen peroxide and ferric salt in presence of titanium di:oxide |
| WO1994013591A1 (en) * | 1992-12-04 | 1994-06-23 | Kemira Oy | Process for treating waste water |
-
1975
- 1975-06-10 CH CH748475A patent/CH613917A5/en not_active IP Right Cessation
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4402851A (en) | 1981-01-13 | 1983-09-06 | Boliden Aktiebolag | Pumpable composition for water-purifying purpose containing iron (II) sulphate, and a method for producing the same |
| DE3832523C1 (en) * | 1988-09-24 | 1990-01-18 | Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe, De | |
| DE3932174A1 (en) * | 1989-09-27 | 1991-04-11 | Degussa | METHOD FOR REDUCING THE AOX CONTENT IN WATER |
| DE4026831A1 (en) * | 1990-08-24 | 1992-02-27 | Inventa Ag | Catalytic oxidn. of organic components in waste water at low temp. - using hydrogen peroxide and ferric salt in presence of titanium di:oxide |
| WO1994013591A1 (en) * | 1992-12-04 | 1994-06-23 | Kemira Oy | Process for treating waste water |
| US5611928A (en) * | 1992-12-04 | 1997-03-18 | Kemira Oy | Process for treating waste water |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUE | Assignment |
Owner name: SOLVAY (SCHWEIZ) AG |
|
| PL | Patent ceased | ||
| PL | Patent ceased |