CH645147A5 - A process for deodorising evaporation condensates in the pulp industry - Google Patents
A process for deodorising evaporation condensates in the pulp industry Download PDFInfo
- Publication number
- CH645147A5 CH645147A5 CH543880A CH543880A CH645147A5 CH 645147 A5 CH645147 A5 CH 645147A5 CH 543880 A CH543880 A CH 543880A CH 543880 A CH543880 A CH 543880A CH 645147 A5 CH645147 A5 CH 645147A5
- Authority
- CH
- Switzerland
- Prior art keywords
- condensates
- evaporation
- hydrogen peroxide
- pulping
- evaporation condensates
- Prior art date
Links
- 238000001704 evaporation Methods 0.000 title claims description 28
- 230000008020 evaporation Effects 0.000 title claims description 28
- 238000000034 method Methods 0.000 title claims description 16
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 35
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 10
- 239000000126 substance Substances 0.000 claims description 10
- 238000004537 pulping Methods 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 229910001868 water Inorganic materials 0.000 claims description 7
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims description 3
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 claims description 2
- 238000005259 measurement Methods 0.000 claims description 2
- 239000002699 waste material Substances 0.000 claims description 2
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims 2
- 239000000460 chlorine Substances 0.000 claims 2
- 229910052801 chlorine Inorganic materials 0.000 claims 2
- 230000029087 digestion Effects 0.000 claims 2
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 claims 2
- HYBBIBNJHNGZAN-UHFFFAOYSA-N furfural Chemical compound O=CC1=CC=CO1 HYBBIBNJHNGZAN-UHFFFAOYSA-N 0.000 claims 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 claims 2
- 230000035943 smell Effects 0.000 claims 2
- ZFFTZDQKIXPDAF-UHFFFAOYSA-N 2-Furanmethanethiol Chemical compound SCC1=CC=CO1 ZFFTZDQKIXPDAF-UHFFFAOYSA-N 0.000 claims 1
- 239000004155 Chlorine dioxide Substances 0.000 claims 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 235000019398 chlorine dioxide Nutrition 0.000 claims 1
- 229910001919 chlorite Inorganic materials 0.000 claims 1
- 229910052619 chlorite group Inorganic materials 0.000 claims 1
- QBWCMBCROVPCKQ-UHFFFAOYSA-N chlorous acid Chemical compound OCl=O QBWCMBCROVPCKQ-UHFFFAOYSA-N 0.000 claims 1
- 238000009833 condensation Methods 0.000 claims 1
- 230000005494 condensation Effects 0.000 claims 1
- 238000010924 continuous production Methods 0.000 claims 1
- 238000004332 deodorization Methods 0.000 claims 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 claims 1
- 238000002386 leaching Methods 0.000 claims 1
- 229910052938 sodium sulfate Inorganic materials 0.000 claims 1
- 235000011152 sodium sulphate Nutrition 0.000 claims 1
- 238000005406 washing Methods 0.000 claims 1
- 239000012190 activator Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 1
- 229940075397 calomel Drugs 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical compound Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 159000000014 iron salts Chemical class 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 235000014380 magnesium carbonate Nutrition 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/06—Treatment of pulp gases; Recovery of the heat content of the gases; Treatment of gases arising from various sources in pulp and paper mills; Regeneration of gaseous SO2, e.g. arising from liquors containing sulfur compounds
- D21C11/08—Deodorisation ; Elimination of malodorous compounds, e.g. sulfur compounds such as hydrogen sulfide or mercaptans, from gas streams
Landscapes
- Paper (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
- Detergent Compositions (AREA)
Description
Aufgabe der Erfindung ist es, ein Verfahren zu schaffen, mit dem die geruchsintensiven Stoffe der Eindampfkondensate vernichtet werden können ohne zusätzlichen apparativen Aufwand. The object of the invention is to provide a method with which the odor-intensive substances of the evaporation condensates can be destroyed without additional equipment.
Es wurde nun gefunden, dass Eindampfkondensate, die bei den Aufschlussverfahren der Zellstoffindustrie anfallen, praktisch vollständig von den in ihnen enthaltenen geruchsintensiven Stoffen kontinuierlich befreit werden können, wenn man den Eindampfkondensaten Wasserstoffperoxid bei einer Temperatur von 20-95°C zusetzt. It has now been found that evaporation condensates, which are obtained in the pulping process of the pulp industry, can be practically completely freed of the odor-intensive substances contained in them if hydrogen peroxide is added to the evaporation condensates at a temperature of 20-95 ° C.
Dabei werden beispielsweise 0,05-2 kg Wasserstoffperoxid For example, 0.05-2 kg of hydrogen peroxide
100 gew.%ig, bevorzugt 0,05-0,2 kg Wasserstoffperoxid 100 gew.%ig, pro 1000 kg Eindampfkondensat verwendet. 100% by weight, preferably 0.05-0.2 kg of hydrogen peroxide 100% by weight, used per 1000 kg of evaporation condensate.
Die Reaktionsdauer beträgt je nach Konzentration der anwesenden geruchsintensiven Stoffe und der eingesetzten Menge Wasserstoffperoxid beispielsweise 0,5-240 min. Depending on the concentration of the odor-intensive substances present and the amount of hydrogen peroxide used, the reaction time is, for example, 0.5-240 min.
Die besten Mengen an Wasserstoffperoxid und die beste Einwirkungszeit ist durch einen Handversuch leicht feststellbar. The best amounts of hydrogen peroxide and the best exposure time can easily be determined by hand.
Ein solcher Versuch ist auch deshalb zu empfehlen, da die Eindampfkondensate neben den zu oxidierenden geruchsintensiven Stoffen noch - wie schon gesagt - andere oxidier-bare Verbindungen, vor allem Schwefeldioxid, enthalten. Bei zu grosser Menge von Schwefeldioxid können daher die Eindampfkondensate vor der Behandlung mit Wasserstoffperoxid durch Strippen mit Wasserdampf von einem Teil oder vollständig von SO2 und auch anderen leicht flüchtigen Stoffen befreit werden, um die Menge an einzusetzendem Wasserstoffperoxid zu verringern. Die dabei zu verwendende Menge Dampf liegt weit unter der Menge, die bisher verwendet wurde, aber niemals zur effektiven Entfernung der geruchsintensiven Stoffe führte. Such an attempt is also recommended because the evaporation condensates also contain - as already mentioned - other oxidizable compounds, especially sulfur dioxide, in addition to the odor-intensive substances to be oxidized. If the amount of sulfur dioxide is too large, some or all of the evaporation condensates can be freed of SO2 and other volatile substances by stripping with steam before treatment with hydrogen peroxide in order to reduce the amount of hydrogen peroxide to be used. The amount of steam to be used is far below the amount that has been used so far, but never led to the effective removal of the odor-intensive substances.
Auch ein kurzes Luftdurchblasen kann die SCh-Menge ver-ringen. A short blow of air can also reduce the amount of SCh.
Es ist auch möglich, das Wasserstoffperoxid nicht sämtlichen anfallenden Kondensaten, sondern bei geringer Geruchsbelastung nur den am stärksten belasteten Kondensaten zuzufügen. Selbstverständlich können die Eindampfkondensate auch zu einem einzigen Kondensat vereinigt und diese dann nach dem erfmdungsgemässen Verfahren behandelt werden. It is also possible not to add the hydrogen peroxide to all of the condensates, but only to the most heavily loaded condensates if the odor is low. Of course, the evaporation condensates can also be combined to form a single condensate and then treated according to the method according to the invention.
Es war nicht vorhersehbar, dass durch einfaches Zumischen des Wasserstoffperoxids die Oxidationsreaktion ohne Zufügen von Aktivatoren, wie z.B. Eisensalzen, in kurzer Zeit ansprang und in kurzen bis relativ kurzen Zeitspannen beendet war. It was not foreseeable that by simply adding the hydrogen peroxide, the oxidation reaction without the addition of activators such as e.g. Iron salts, started up in a short time and ended in short to relatively short periods of time.
Die erfindungsgemäss oxidierten Eindampfkondensate können in den Kreislauf des Zellstoffaufschlusses zurückgeführt werden, z.B. als Waschwasser in der oben erwähnten Waschstrasse für die Ablauge. Dies bedeutet eine grössere Ersparnis an Wasser. The evaporation condensates oxidized according to the invention can be returned to the cellulose pulping cycle, e.g. as wash water in the above-mentioned car wash for the waste water. This means a greater saving in water.
Ferner können diese Kondensate, da sie frei von zusätzlichen Aktivatoren sind, auch zum Spülen der Eindampfanlage selbst verwendet werden. Furthermore, since they are free of additional activators, these condensates can also be used to rinse the evaporation system itself.
Auch einem Einleiten der erfindungsgemäss behandelten Kondensate in den Vorfluter steht aus Gründen der Geruchsemission nichts im Wege. There is also nothing to prevent the condensates treated according to the invention from being introduced into the receiving water because of the odor emission.
Die Dosierung von Wasserstoffperoxid kann in üblicher Weise erfolgen, bevorzugt mit Hilfe von Redox-Messungen. The hydrogen peroxide can be metered in in a customary manner, preferably with the aid of redox measurements.
Das Verfahren lässt sich für die Eindampfkondensate aller obgenannten Aufschlussverfahren für Zellstoffe anwenden, d.h. sowohl für die Sulfit-, Bisulfit- wie auch für die alkalischen Verfahren. Sehr gute Ergebnisse wurden z.B. beim sauren Magnesitbisulfit-Verfahren erhalten. The method can be used for the evaporation condensates of all of the above pulping processes, i.e. for both the sulfite, bisulfite and alkaline processes. Very good results have been e.g. obtained in the acidic magnesite bisulfite process.
Beispiel example
In einer Zellstoffabrik werden täglich 5001 «Magnefite»-Zellstoff erzeugt; die Ablaugen werden in einer mehrstufigen Eindampfanlage auf 58 Gew.% Trockengehalt gebracht und verbrannt. Pro Stunde fallen folgende Kondensatmengen in verschiedenen Eindampfstufen mit Ausnahme des sogenannten Kondensates 1, das nicht behandelt wurde, an: 5001 “Magnefite” pulp are produced daily in a pulp mill; the waste liquors are brought to 58% by weight dry matter in a multi-stage evaporation plant and burned. The following amounts of condensate per hour occur in various evaporation stages with the exception of the so-called condensate 1, which has not been treated:
sog. Kondensate 2+3 (geringste Belastung) 120 t/h sog. Kondensate 4+5 (mittlere Belastung) 70 t/h So-called condensates 2 + 3 (lowest load) 120 t / h so-called condensates 4 + 5 (medium load) 70 t / h
2 2nd
5 5
10 10th
15 15
20 20th
25 25th
30 30th
35 35
40 40
45 45
50 50
55 55
60 60
65 65
3 3rd
645147 645147
sog. Nachkondensate (starke Belastung z.T. auch durch SO2) 10 t/h So-called post-condensates (heavy loads, sometimes also due to SO2) 10 t / h
Die Kondensate 2+3 und 4+5 haben einen intensiv muffigen Geruch, der in stärkerer Verdünnung eine Ähnlichkeit zu Kaffeesatz-Ausdünstung aufweist. Die Nachkondensate enthalten die am leichtesten wasserdampfflüchtenden Verunreinigungen. Ihr Geruch ist intensiv stechend, in Verdünnung ebenfalls muffig kaffeeartig. The condensates 2 + 3 and 4 + 5 have an intensely musty smell, which, when diluted to a greater extent, is similar to coffee grounds. The post-condensates contain the easiest water vapor escaping impurities. Their smell is intensely pungent, also musty coffee-like in dilution.
In die Kondensatleitung wird knapp vor Eintritt in die Förderpumpe Wasserstoffperoxid 50 gew.%ig eindosiert. Nach der Förderpumpe wird mittels einer Platin-Kalomel-Elektrode laufend das Potential gemessen. Die dosierten Wasserstoffperoxidmengen in die Kondensate 2+3 sind ca. 400 ml/min. bei Einregelung auf 220 mV, in die Kondensate 4+5 ca. 400 ml/min. bei Einregelung auf 250 mV, in die Hydrogen peroxide 50% by weight is metered into the condensate line just before entry into the feed pump. After the feed pump, the potential is continuously measured using a platinum calomel electrode. The metered amounts of hydrogen peroxide in the condensates 2 + 3 are approx. 400 ml / min. with regulation to 220 mV, in the condensates 4 + 5 approx. 400 ml / min. with regulation to 250 mV, in the
Nachkondensate ca. 500 ml/min. bei Einregelung auf 150 mV. Die Kondensate 2+3 werden zur Spülung der Anlage verwendet. Die Reaktionsdauer nach Zugabe des Wasserstoffperoxids beträgt ca. 15 min. Post-condensates approx. 500 ml / min. when regulated to 150 mV. Condensates 2 + 3 are used to flush the system. The reaction time after adding the hydrogen peroxide is approximately 15 minutes.
5 Die Kondensate 4+5 werden mit den Nachkondensaten vereinigt und in einem Behälter aus Edelstahl 1-2 h lang aufbewahrt. Die Temperatur liegt zwischen 65-95°C. Nach dieser Behandlung ist der typische unangenehme, z.T. stechende Geruch völlig entfernt. Der verbliebene, leicht blu-10 mige Geruch wird als angenehm empfunden und stellt keine Belästigung dar. Die oxidierten Kondensate werden zur Waschung des Zellstoffes in der Laugenerfassung verwendet. Sie gehen damit zu einem grossen Teil in die Eindampfung zurück und bilden damit keine Belastung des Fabrikationsab-ls wassers. Die angegebenen Potentiale wurden durch Vorversuche erhalten. 5 The condensates 4 + 5 are combined with the post-condensates and stored in a stainless steel container for 1-2 hours. The temperature is between 65-95 ° C. After this treatment, the typical unpleasant, sometimes pungent smell completely removed. The remaining, slightly bluish smell is perceived as pleasant and does not represent a nuisance. The oxidized condensates are used to wash the pulp in the lye detection. To a large extent, they go back into the evaporation and thus do not cause any pollution of the manufacturing waste water. The indicated potentials were obtained through preliminary tests.
B B
Claims (4)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19792928652 DE2928652A1 (en) | 1979-07-16 | 1979-07-16 | METHOD FOR THE DESODORATION OF EVAPORATION CONDENSATES IN THE PULP INDUSTRY |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH645147A5 true CH645147A5 (en) | 1984-09-14 |
Family
ID=6075827
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH543880A CH645147A5 (en) | 1979-07-16 | 1980-07-15 | A process for deodorising evaporation condensates in the pulp industry |
Country Status (8)
| Country | Link |
|---|---|
| AT (1) | AT375108B (en) |
| CA (1) | CA1139507A (en) |
| CH (1) | CH645147A5 (en) |
| DE (1) | DE2928652A1 (en) |
| FR (1) | FR2461777A1 (en) |
| IT (1) | IT1128928B (en) |
| NO (1) | NO801311L (en) |
| SE (1) | SE445654B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4442226A1 (en) * | 1994-11-26 | 1995-06-14 | Goes Ges Fuer Sanierungsmasnah | Thixotropic sludge decontamination contg. lignin esp. from pulp mfr. |
| SE531478C2 (en) * | 2007-11-26 | 2009-04-21 | Processum Biorefinery Initiative Ab | Process for the extraction of ammonium salt and methanol from liquid emanating from impure condensate resulting from cellulose pulp production |
| US20150322626A1 (en) * | 2014-05-06 | 2015-11-12 | Weyerhaeuser Nr Company | Reduced furfural content in polyacrylic acid crosslinked cellulose fibers |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE218344C (en) * | ||||
| DE176690C (en) * | ||||
| DE340126C (en) * | 1919-02-27 | 1921-09-01 | Ludwig Schmidt Dr | Process for improving the smell of Sulphatterpentinoel |
| US2409614A (en) * | 1942-01-15 | 1946-10-22 | Hercules Powder Co Ltd | Refining sulfate turpentine |
| US3705098A (en) * | 1971-02-22 | 1972-12-05 | Fmc Corp | Sewage treatment with hydrogen peroxide |
| FR2192981B1 (en) * | 1972-07-21 | 1988-11-10 | Air Liquide Fr | |
| US3796628A (en) * | 1972-09-12 | 1974-03-12 | Cariboo Pulp And Paper Co | Method for reducing sulfide odors from kraft mill lime kiln stacks |
-
1979
- 1979-07-16 DE DE19792928652 patent/DE2928652A1/en not_active Withdrawn
-
1980
- 1980-04-14 FR FR8008322A patent/FR2461777A1/en active Granted
- 1980-04-24 CA CA000350593A patent/CA1139507A/en not_active Expired
- 1980-05-05 NO NO801311A patent/NO801311L/en unknown
- 1980-07-10 IT IT68096/80A patent/IT1128928B/en active
- 1980-07-15 SE SE8005174A patent/SE445654B/en unknown
- 1980-07-15 AT AT0367680A patent/AT375108B/en not_active IP Right Cessation
- 1980-07-15 CH CH543880A patent/CH645147A5/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| ATA367680A (en) | 1983-11-15 |
| IT8068096A0 (en) | 1980-07-10 |
| SE445654B (en) | 1986-07-07 |
| CA1139507A (en) | 1983-01-18 |
| NO801311L (en) | 1981-01-19 |
| FR2461777B1 (en) | 1984-10-19 |
| IT1128928B (en) | 1986-06-04 |
| SE8005174L (en) | 1981-01-17 |
| DE2928652A1 (en) | 1981-02-19 |
| FR2461777A1 (en) | 1981-02-06 |
| AT375108B (en) | 1984-07-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PL | Patent ceased |