SE462169B - PROCEDURE FOR CLEANING OF CONDENSATED FROM THE SULPHATE PROCESS - Google Patents
PROCEDURE FOR CLEANING OF CONDENSATED FROM THE SULPHATE PROCESSInfo
- Publication number
- SE462169B SE462169B SE8202251A SE8202251A SE462169B SE 462169 B SE462169 B SE 462169B SE 8202251 A SE8202251 A SE 8202251A SE 8202251 A SE8202251 A SE 8202251A SE 462169 B SE462169 B SE 462169B
- Authority
- SE
- Sweden
- Prior art keywords
- condensate
- column
- catalyst
- amount
- total
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 21
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 title claims abstract description 11
- 229910021653 sulphate ion Inorganic materials 0.000 title claims description 9
- 238000004140 cleaning Methods 0.000 title 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000007789 gas Substances 0.000 claims abstract description 16
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 6
- 239000001301 oxygen Substances 0.000 claims abstract description 6
- 239000003054 catalyst Substances 0.000 claims description 12
- 239000003921 oil Substances 0.000 claims description 12
- 238000001914 filtration Methods 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims 1
- 239000003344 environmental pollutant Substances 0.000 abstract description 3
- 231100000719 pollutant Toxicity 0.000 abstract description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 27
- 150000001875 compounds Chemical class 0.000 description 15
- LSDPWZHWYPCBBB-UHFFFAOYSA-N Methanethiol Chemical compound SC LSDPWZHWYPCBBB-UHFFFAOYSA-N 0.000 description 11
- 230000003647 oxidation Effects 0.000 description 11
- 238000007254 oxidation reaction Methods 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 9
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 8
- 238000001704 evaporation Methods 0.000 description 8
- 230000008020 evaporation Effects 0.000 description 8
- 239000000126 substance Substances 0.000 description 8
- 230000008929 regeneration Effects 0.000 description 7
- 238000011069 regeneration method Methods 0.000 description 7
- 238000004581 coalescence Methods 0.000 description 6
- 238000002474 experimental method Methods 0.000 description 6
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 229910052717 sulfur Inorganic materials 0.000 description 5
- 239000011593 sulfur Substances 0.000 description 5
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 4
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 4
- 231100000331 toxic Toxicity 0.000 description 4
- 230000002588 toxic effect Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 150000002894 organic compounds Chemical class 0.000 description 3
- 229920001021 polysulfide Polymers 0.000 description 3
- 239000005077 polysulfide Substances 0.000 description 3
- 150000008117 polysulfides Polymers 0.000 description 3
- 239000000344 soap Substances 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 238000010411 cooking Methods 0.000 description 2
- WQOXQRCZOLPYPM-UHFFFAOYSA-N dimethyl disulfide Chemical compound CSSC WQOXQRCZOLPYPM-UHFFFAOYSA-N 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000013383 initial experiment Methods 0.000 description 2
- 235000019988 mead Nutrition 0.000 description 2
- HEDOODBJFVUQMS-UHFFFAOYSA-N n-[2-(5-methoxy-1h-indol-3-yl)ethyl]-n-methylpropan-2-amine Chemical group COC1=CC=C2NC=C(CCN(C)C(C)C)C2=C1 HEDOODBJFVUQMS-UHFFFAOYSA-N 0.000 description 2
- 238000003918 potentiometric titration Methods 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 2
- 235000010265 sodium sulphite Nutrition 0.000 description 2
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 2
- 235000019345 sodium thiosulphate Nutrition 0.000 description 2
- 241000269627 Amphiuma means Species 0.000 description 1
- 241000972773 Aulopiformes Species 0.000 description 1
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- 229940123973 Oxygen scavenger Drugs 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 230000001154 acute effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000010170 biological method Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000001212 derivatisation Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- -1 e.g. methanol Chemical class 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 239000003205 fragrance Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-M hexanoate Chemical compound CCCCCC([O-])=O FUZZWVXGSFPDMH-UHFFFAOYSA-M 0.000 description 1
- 239000002655 kraft paper Substances 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 244000005700 microbiome Species 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 150000002898 organic sulfur compounds Chemical class 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 239000000123 paper Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920001515 polyalkylene glycol Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000004537 pulping Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000011347 resin Chemical class 0.000 description 1
- 229920005989 resin Chemical class 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 235000019515 salmon Nutrition 0.000 description 1
- HYHCSLBZRBJJCH-UHFFFAOYSA-M sodium hydrosulfide Chemical compound [Na+].[SH-] HYHCSLBZRBJJCH-UHFFFAOYSA-M 0.000 description 1
- HYHCSLBZRBJJCH-UHFFFAOYSA-N sodium polysulfide Chemical compound [Na+].S HYHCSLBZRBJJCH-UHFFFAOYSA-N 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 150000004763 sulfides Chemical class 0.000 description 1
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical compound OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 description 1
- 239000003784 tall oil Substances 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000820 toxicity test Toxicity 0.000 description 1
- 125000000026 trimethylsilyl group Chemical group [H]C([H])([H])[Si]([*])(C([H])([H])[H])C([H])([H])[H] 0.000 description 1
- 238000005406 washing Methods 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
-
- 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
- D21C11/0057—Oxidation of liquors, e.g. in order to reduce the losses of sulfur compounds, followed by evaporation or combustion if the liquor in question is a black liquor
Landscapes
- Treating Waste Gases (AREA)
- Paper (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Carbon And Carbon Compounds (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
Abstract
Description
15 20 462 169 2 olika sätt i processen, något som emellertid icke anses vara av betydelse i detta sammanhang. 15 20 462 169 2 different ways in the process, something which, however, is not considered important in this context.
Från svartluten avskiljes en såpa (sulfatsåpa). Denna be- står väsentligen av försåpade fettsyror och hartssyror (abietin- syror) men innehåller även oförsåpade föreningar. Såpan tar man vanligen vara på, och den omformas då gärna till s.k. tallolja. Även indunstningskondensaten kommer att innehålla mer eller mind- re finfördelad "olja", dvs. en vattenutlöslig fas, något som kom- mer att vara en olägenhet vid varje vidare behandling av dessa.A soap (sulphate soap) is separated from the black liquor. This consists essentially of saponified fatty acids and resin acids (abietic acids) but also contains unsaponified compounds. The soap is usually used, and it is then often transformed into so-called tall oil. The evaporation condensate will also contain more or less finely divided "oil", ie. a water-soluble phase, which will be a disadvantage in any further treatment of these.
De här omnämnda kondensaten har det gemensamt att de inne- håller diverse flyktiga ämnen, varav en del är lägre svavelhal- tiga föreningar. Speciellt under indunstningen avgår illaluktande och giftiga gaser, såsom vätesulfid (H25), metylmerkapten (CHSSH) och liknande, från svartluten, varav en icke oväsentlig del kom- mer att återfinnas i kondensaten. Kondensaten är därför illaluk- tande och toxiska.The condensates mentioned here have in common that they contain various volatile substances, some of which are lower sulfur-containing compounds. Especially during evaporation, malodorous and toxic gases, such as hydrogen sulfide (H25), methyl mercapte (CHSSH) and the like, emit from the black liquor, a not insignificant part of which will be found in the condensates. The condensates are therefore foul-smelling and toxic.
Innehållet av metanol bl.a. betyder att utsläpp av konden- sat kommer att medföra en belastning på recipienten i form av upplöst organiskt material med tillhörande kemisk syreförbruk- ning (COD) och biokemísk syreförbrukning (BOD). De tre förhål- landena lukt, toxicitet gentemot akvatiskt liv samt organisk be- lastning betyder att sulfatprocessens kondensat representerar ett allvarligt miljöproblem. Samtidigt begränsas också användnings- möjligheterna av orenade kondensat som vätskekälla inom processen genom deras avgivning av giftiga och illaluktande gaser samt de- ras innehåll av finfördelade oljor.The content of methanol i.a. means that discharge of the condensate will place a load on the recipient in the form of dissolved organic material with associated chemical oxygen demand (COD) and biochemical oxygen demand (BOD). The three conditions odor, toxicity to aquatic life and organic pollution mean that the condensate of the sulphate process represents a serious environmental problem. At the same time, the possibilities of using crude condensates as a liquid source in the process are also limited by their release of toxic and foul-smelling gases and their content of finely divided oils.
De metoder som i dag utnyttjas för rening av sulfatpro- cessens kondensat är först och främst baserade på avdrivning av flyktiga föreningar (däribland metanol och illaluktande ämnen) med hjälp av ånga eller luft (stripping) (2a, Zb). De avdrivna gaserna/ângorna går gärna till destruktion genom förbränning, tillsammans med en del okondenserbara gaser från koknings- och återvinningsprocessen.The methods currently used for purifying the condensate of the sulphate process are primarily based on the evaporation of volatile compounds (including methanol and odorous substances) by means of steam or air (stripping) (2a, Zb). The evaporated gases / vapors tend to be destroyed by combustion, together with some non-condensable gases from the boiling and recovery process.
En reningsprocess baserad på nedbrytning med hjälp av mikroorganismer utnyttjas också (3).A purification process based on degradation using microorganisms is also used (3).
Föreliggande förfarande tar sikte på att avlägsna konden- satens illaluktande ämnen med hjälp av kombinerad oxidation och adsorption efter ett föregående avlägsnande av finfördelad olja bl.a. med hjälp av koalescens, när detta krävs. En liten försöks- 10 15 20 25 30 35 40 ° 462 169 anläggning har under ett par år testats vid en sulfatfabrik för studium av olika kondensattyper, katalysatortyper, livslängd och regenereringsmöjligheter för katalysatorn osv.The present process aims at removing the odorous substances of the condensate by means of combined oxidation and adsorption after a previous removal of finely divided oil, e.g. using coalescence, when required. A small experimental plant has been tested for a couple of years at a sulphate factory to study different condensate types, catalyst types, service life and regeneration possibilities for the catalyst, and so on.
Det är känt att vätesulfidgas i luft oxideras på en lämp- lig katalysator, såsom t.ex. aktivt kol. Vid denna gasreaktion omvandlas H25 till elementärt svavel. Processen kan föras vidare till svaveldioxid (S02), som ju också (tillsammans med någon S05) är slutprodukten vid förbränning av H25, svavel och många andra svavelföroreningar. Man har även föreslagit att rena illaluktande gaser med hjälp av alkali och aktivt kol.It is known that hydrogen sulfide gas in air is oxidized on a suitable catalyst, such as e.g. activated carbon. In this gas reaction, H25 is converted to elemental sulfur. The process can be passed on to sulfur dioxide (SO2), which is also (together with some SO5) the end product in the combustion of H25, sulfur and many other sulfur pollutants. It has also been proposed to purify malodorous gases with the aid of alkali and activated carbon.
Vätesulfid är löslig i alkali, t.ex. i natronlut, genom att det bildas sulfider (NaHS och/eller Na2S i NaOH). I sulfatpro- cessens mycket starkt basiska vitlut är, såsom nämnts, natrium- hydroxid och natriumsulfid de aktiva kokningskemikalierna. Sådan vitlut oxideras långsamt av luft, och oxidationsprodukterna kom- mer att vara natriumsulfit, natriumtiosulfat och natriumsulfat.Hydrogen sulfide is soluble in alkali, e.g. in sodium hydroxide solution, by the formation of sulphides (NaHS and / or Na2S in NaOH). In the very strongly basic white liquor of the sulphate process, as mentioned, sodium hydroxide and sodium sulphide are the active cooking chemicals. Such white liquor is slowly oxidized by air, and the oxidation products will be sodium sulfite, sodium thiosulfate and sodium sulfate.
Genom närvaro av lämplig syreöverförare eller katalysator kan oxidationstiden reduceras väsentligt, och det bildas natriumpoly- sulfid och natriumtiosulfat. Som exempel kan nämnas inblandning av en viss del svartlut (PPI-patent) eller användning av en spe- ciell katalysatormassa (Meads Moxyprosess) (4, 5).By the presence of a suitable oxygen scavenger or catalyst, the oxidation time can be significantly reduced, and sodium polysulfide and sodium thiosulfate are formed. Examples are the mixing of a certain amount of black liquor (PPI patent) or the use of a special catalyst mass (Meads Moxy process) (4, 5).
Aktivt kol är allmänt känt inom reningstekniken för avlägs- nande av små mängder föroreningar. Detta är baserat på ämnets stora inre yta. Ytan blockeras av de adsorberade ämnena, så att en eller annan form av regenerering kommer att krävas när det är fråga om större mängder föroreningar.Activated carbon is generally known in the purification technique for removing small amounts of pollutants. This is based on the large inner surface of the substance. The surface is blocked by the adsorbed substances, so that some form of regeneration will be required in the case of large amounts of contaminants.
Föreliggande förfarande utmärkes av att kondensaten och den syrehaltíga gasen ledes medströms genom en kolonn inneållande ka- talysatorn, varefter katalysatorn eventuellt regenereras.The present process is characterized in that the condensate and the oxygen-containing gas are passed downstream through a column containing the catalyst, after which the catalyst is optionally regenerated.
FÖRSÖK Förorenade, illaluktande kondensat från en sulfatfabrik ledes tillsammans med luft genom en kolonn fylld med aktivt kol.EXPERIMENT Contaminated, foul-smelling condensate from a sulphate plant is led together with air through a column filled with activated carbon.
Inledande försök visade att l) Lukten avlägsnades genom behandlingen. 2) Vätesulfid och metylmerkaptan avlägsnades (påvisades ge- nom potentiometriska tireringar). 3) Lukt, vätesulfid och metylmerkaptan avlägsnades icke om icke tillräcklig mängd luft passerade tillsammans med vätskan. 4) Kolonnen miste effekten efter en viss tid. 10 15 4 462 169 Förutom det faktum att lukt, vätesulfid och metylmerkaptan avlägsnas genom denna metod, visade alltså försöken att det torde vara en luftoxidation som ägde rum (punkt l, 2, 3), och att ko- lonnmaterialet inverkade (punkt 4), dvs. att det var en kataly- tisk oxidation.Initial experiments showed that l) The odor was removed by the treatment. 2) Hydrogen sulfide and methyl mercaptan were removed (detected by potentiometric tirations). 3) Odor, hydrogen sulfide and methyl mercaptan were not removed if insufficient air passed along with the liquid. 4) The column loses the effect after a certain time. Thus, in addition to the fact that odor, hydrogen sulphide and methyl mercaptan are removed by this method, the experiments showed that it was an air oxidation that took place (points 1, 2, 3), and that the column material had an effect (point 4). , i.e. that it was a catalytic oxidation.
Det antogs att vätesulfid oxiderades till elementärt sva- vel, som satt kvar på kolonnmaterialet. Detta antagande bekräfta- des genom att varm vitlut, som sändes genom kolonnen, anrikades på polysulfid. (Färg gul/orange/röd, beroende på koncentrationen.It was assumed that hydrogen sulfide was oxidized to elemental sulfur, which remained on the column material. This assumption was confirmed by enriching hot white liquor sent through the column on polysulfide. (Color yellow / orange / red, depending on the concentration.
Bestämdes kvantitativt genom potentiometrisk títrering efter över- föring till ekvivalent mängd tiosulfat med hjälp av natriumsulfit.) Det är känt att elementärt svavel löses i sulfidlösningar, som t.ex. vitlut och grönlut. Försöket visade därmed också att sul- fatprocessen i sig själv har kemikalier som kan användas för att befria kolonnmaterialet från det svavel som avsättes.Determined quantitatively by potentiometric titration after conversion to the equivalent amount of thiosulfate using sodium sulfite.) It is known that elemental sulfur is dissolved in sulfide solutions, such as e.g. white liquor and green liquor. The experiment thus also showed that the sulphate process itself has chemicals that can be used to free the column material from the sulfur that is deposited.
Det obehandlade kondensatet innehöll oljeliknande droppar av varierande mängd och droppstorlek. Efter att ha passerat ge- nom kolonnen var kondensatet emellertid helt klart. En sådan olje- avsättning får antas reducera kolonnmaterialets aktiva yta. Detta bekräftades genom att kolonnen efter att ha mist sin effekt åter igen blev effektiv efter behandling med ånga i ca 180-l90°C.The untreated condensate contained oil-like droplets of varying amount and droplet size. However, after passing through the column, the condensate was completely clear. Such an oil deposit may be assumed to reduce the active surface of the column material. This was confirmed by the column, after losing its effect, becoming effective again after treatment with steam at about 180-190 ° C.
Genom att följa kondensaten en tid fann man att oljemäng- den kunde variera inom vida gränser. Det gjordes därför försök att avlägsna oljan innan kondensatet gick till kolonnen. Effek- tiv oljeavlägsning uppnås genom att man först avlägsnar stora droppar genmnattdessa tillätes flyta upp på vattenfasen och där- efter avlägsnar de fínfördelade, svävande oljedropparna från vat- tenfasen med hjälp av koalescens.By following the condensate for a while, it was found that the amount of oil could vary within wide limits. Attempts were therefore made to remove the oil before the condensate went to the column. Effective oil removal is achieved by first removing large droplets through the night, allowing them to float on the water phase and then removing the finely divided, suspended oil droplets from the water phase by coalescence.
Prover av de vattenklara kondensaten efter koalescensfilt- reringen extraheras med organiska lösningsmedel, och extrakten undersökes med hjälp av gaskromatografi. Analyserna visade att det fanns närvarande ett mycket stort antal polära och opolära organiska föreningar. Motsvarande analyser av prover uttagna ef- ter kolonngenomgången visade att dessa föreningar avlägsnades i det närmaste fullständigt genom behandlingen. De föreningar som man fick fram genom denna analysmetod antogs i huvudsak vara de högre organiska föreningarna. Då dessa, liksom även vätesulfid och lägre organiska svavelföreningar, torde kunna förväntas ha akut giftverkan på livet i recipienten, utnyttjades kondensat- 10 15 20 25 S 462 169 prover vid studier av dödligheten på laxyngel. Det befanns att de obehandlade var 3-35 gånger så toxiska som de behandlade.Samples of the water-clear condensates after the coalescence filtration are extracted with organic solvents, and the extracts are examined by means of gas chromatography. The analyzes showed that there were a very large number of polar and non-polar organic compounds present. Corresponding analyzes of samples taken after the column review showed that these compounds were almost completely removed by the treatment. The compounds obtained by this analytical method were mainly assumed to be the higher organic compounds. As these, as well as hydrogen sulphide and lower organic sulfur compounds, could be expected to have an acute toxic effect on the life of the recipient, condensate samples were used in studies of the mortality of salmon fry. It was found that the untreated were 3-35 times as toxic as the treated ones.
Toxicitetsförsöken (96 timmar - LCSO) utfördes vid Norsk institutt for vannforskning (NIVA). De gaskromatografiska under- sökningarna utfördes vid Sentralinstitutt for industriell forsk- ning (SI) med hjälp av b1.a. glaskapillärkolonn och flamjonisa- tionsdetektor. Innehållet av lâgkokande organiska föreningar, såsom t.ex. metanol, har studerats vid PFI med hjälp av en gas- kromatograf med polyalkylenglykol-kolonn och varmtrâdsdetektor.The toxicity tests (96 hours - LCSO) were performed at the Norwegian Institute for Water Research (NIVA). The gas chromatographic surveys were carried out at the Central Institute for Industrial Research (SI) using b1.a. glass capillary column and flame ionization detector. The content of low-boiling organic compounds, such as e.g. methanol, has been studied in PFI using a gas chromatograph with polyalkylene glycol column and hot wire detector.
Förutom metanol finner man spår av en annan förening (uppskattad till under 1,5 procent av metanolmängden). Detta tyder på att metanol i praktiken bör kunna anrikas från de renade kondensa- ten utan för stora krav på fraktionerad separation. Luktstudíer med hjälp av head-space-teknik visade reduktion i antal och to- talínnehäll av avgående luktämnen vid 4OOC (SI).In addition to methanol, traces of another compound are found (estimated at less than 1.5 percent of the amount of methanol). This indicates that in practice methanol should be able to be enriched from the purified condensates without too great demands on fractional separation. Odor studies using head-space technology showed a reduction in the number and total content of emitting odorants at 4OOC (SI).
Den försöksanläggning som utnyttjades visas schematiskt på ritningen. Dess uppbyggnad är som följer: p Med hjälp av ventiler (1, 2) och pumpar (Pl, P2) tar man ut en delström från kondensatledningen (i exemplet på ritningen tas denna från indunstníngsstationens avlopp). Eventuella fasta partiklar och större oljedroppar avskïfies i ett förfiflter (3) med överlopp (4). Koalescensenheten består av två parallellkopp- lade koalescensfilterpatroner (5) av typen Balston. Oxidationen utföres i en 4 m stålkolonn med 8 liter katalysatormassa. Kolon- nen har tillförsel av kondensat (alternativt vitlut för avlägs- nande av utfällt svavel) via pump (P3) och mängdmätare (9), tryckluft via mätare (18) samt ånga för regenerering. Kolonnens effektivitet övervakas med en H28-detektor monterad under locket i uppsamlingsbehållaren, och ytterligare kontroll får man genom att ta ut prover för luktbedömning och för potentiometrisk ti- trering av H25 och CHSSH. 462 169 6 S t u d i u m av 0 x i d a t i o n s k o 1 o n n e n s v e r k n i n g s g r a d.The experimental facility that was used is shown schematically in the drawing. Its structure is as follows: p Using valves (1, 2) and pumps (P1, P2), a partial current is taken out of the condensate line (in the example in the drawing, this is taken from the evaporation station drain). Any solid particles and larger oil droplets are separated in one liner (3) with overflow (4). The coalescence unit consists of two parallel-connected coalescence filter cartridges (5) of the Balston type. The oxidation is carried out in a 4 m steel column with 8 liters of catalyst mass. The column has a supply of condensate (alternatively white liquor for removal of precipitated sulfur) via pump (P3) and flow meter (9), compressed air via meter (18) and steam for regeneration. The efficiency of the column is monitored with an H28 detector mounted under the lid of the collection container, and further control is obtained by taking samples for odor assessment and for potentiometric titration of H25 and CHSSH. 462 169 6 S t u d i u m av 0 x i d a t i o n s k o 1 o n n e n s v e r k n i n g s g r a d.
Kolonnmaterial: Aktivt kol, 8 liter, kornstorlek 0,5 - 2,5 mm Typ: Lurgi Hydraffin LS supra Anm.: Inledande försök utfört med bl.a. vanligt aktivt kol utan tekniska specifikationer, inköpt från affär i Oslo, gav motsvarande resultat med avseende på lukt, H25 och CH3SH.Column material: Activated carbon, 8 liters, grain size 0.5 - 2.5 mm Type: Lurgi Hydraffin LS supra Note: Initial experiments performed with i.a. ordinary activated carbon without technical specifications, purchased from a store in Oslo, gave similar results with respect to odor, H25 and CH3SH.
Kolonn fylld 2.l0.79 Försök utfört 2.10.-4.l0.79: INDUNSTNINGSKONDENSAT Ingående kondensat: H25 0,1 - 0,9 g S/l CHSSH 0 - 0,3 " H25 + CHSSH 0,1 - 1,2 g S/l pH 7,6 - 8,0 Utgående kondensat: HZS + CHSSH 0 g S/1 pH ca. 9,7 Kondensatmängd 15 l/h, totalt 720 1 Luftmängd ca. 40 " " 1800 l Avlägsnat totalt H25 + CH3SH motsvarande 360 g S Regenereríng med ca. 5 kg ånga (l90°C, 13 kg/cmz) forts. 15.10.-17.10.Column filled 2.l0.79 Experiment performed 2.10.-4.l0.79: EVAPORATION CONDENSATE Included condensate: H25 0.1 - 0.9 g S / l CHSSH 0 - 0.3 "H25 + CHSSH 0.1 - 1, 2 g S / l pH 7.6 - 8.0 Outgoing condensate: HZS + CHSSH 0 g S / 1 pH approx. 9.7 Condensate amount 15 l / h, total 720 1 Air volume approx. 40 "" 1800 l Removed total H25 + CH3SH corresponding to 360 g S Regeneration with about 5 kg of steam (l90 ° C, 13 kg / cm2) continued 15.10.-17.10.
Ingående kondensat: Hzs g 0,1 - 0,7 g s/1 CH,SH 0,1 - 0,3 " Hzš + cH3sH 0,2 - 1,0 g c/1 pH ca. 8 Utgående kondensat: Hzs + cH3sH 0 g s/1 pH ca. 9,6 Kondensatmängd 15 l/h, totalt 350 l Luftmängd 40 " " 910 l Avlägsnat totalt H25 + CHSSH motsvarande 250 g S 462 169 forts. 22.10. - 25.10.Incoming condensate: Hzs g 0.1 - 0.7 gs / 1 CH, SH 0.1 - 0.3 "Hzš + cH3sH 0.2 - 1.0 gc / 1 pH approx. 8 Outgoing condensate: Hzs + cH3sH 0 gs / 1 pH approx. 9.6 Condensate amount 15 l / h, total 350 l Air volume 40 "" 910 l Removed total H25 + CHSSH corresponding to 250 g S 462 169 continued 22.10. - 25.10.
Kondensatmängd totalt 600 1 Luftmängd " 1630 l pH (in) ca. 8 pH (ut) " 9,5 Avlägsnat totalt HZS + CHBSH motsvarande 310 5 S Kondensatmängd efter förra ångregenereringen: 350 1 + 600 l Kondensatmängd totalt: 720 1 + 950 l Avlägsnad H28 + CH3SH totalt motsvarande 540 g S 950 1 1470 l Regenerering med ca. 6 kg ånga (l90°C, 12,8 kg/cmz) Regenerering med ca. 4,5 1 varm vitlut, 30 min.Total amount of condensate 600 1 Amount of air "1630 l pH (in) approx. 8 pH (out)" 9.5 Removed total HZS + CHBSH corresponding to 310 5 S Condensate amount after previous steam regeneration: 350 1 + 600 l Total amount of condensate: 720 1 + 950 l Removed H28 + CH3SH total corresponding to 540 g S 950 1 1470 l Regeneration with approx. 6 kg steam (l90 ° C, 12.8 kg / cmz) Regeneration with approx. 4.5 1 warm white liquor, 30 min.
Dränerad polysulfidhaltíg lut. Tvättning med ca 40 liter vatten forts. 25.2. - 27.2.80 Kondensatmängd totalt 330 1 luftmängd " 1000 l pH (in) ca. 7,8 pH (ut) " -9,7 Avlägsnat totalt H25 + CH3SH motsvarande 230 g/S forts. 4.3 Kondensatmängd totalt 470 1 Luftmängd " 1400 1 Avlägsnat totalt H25 + CHSSH motsvarande 330 g/S 560 g/S Försöksserien avslutad efter behandling av totalt 2270 1 urenat indunstníngskondensat genom avlägsnande av H28 + CH3SH motsvarande 1430 g svavel.Drained polysulfide-containing liquor. Washing with about 40 liters of water cont. 25.2. - 27.2.80 Condensate amount total 330 1 air volume "1000 l pH (in) approx. 7.8 pH (out)" -9.7 Removed total H25 + CH3SH corresponding to 230 g / S cont. 4.3 Condensate amount total 470 1 Air volume "1400 1 Removed total H25 + CHSSH corresponding to 330 g / S 560 g / S The experimental series ended after treatment of a total of 2270 1 purified evaporation condensate by removing H28 + CH3SH corresponding to 1430 g sulfur.
Försök utfört 28.5. - 9.l0.80: KOKERIKONDENSAT Kolonnmateríal som ovan Kolonn fylld 21,5 Ingående kondensat: Hzs + cH3sH spår pH 9,0 - 9,5 462 169 F 8 Utgående kondensat: H75 + CHSSH 0 g/1 pH 9,5 - 10,0 Kondensatmängd 15 1/h, totalt ca. 5000 l Luftmängd 40 " " " 13300 1 Försöket avslutat, kolonnen fortsatt effektiv.Experiments performed 28.5. - 9.l0.80: COOKING CONDENSATE Column material as above Column filled 21.5 Incoming condensate: Hzs + cH3sH traces pH 9.0 - 9.5 462 169 F 8 Outgoing condensate: H75 + CHSSH 0 g / 1 pH 9.5 - 10.0 Condensate amount 15 1 / h, total approx. 5000 l Air volume 40 "" "13300 1 The experiment ended, the column remained effective.
G a s k r o m a t o g r a f i s k a a n a 1 y s e r (utförda på SI) Extraktion med cyklohexan omfattar opolära föreningar, följt av surgörning och extraktion med butylacetat och derivati- sering med ett trimetylsilylreagens för bestämning av de mera polära föreíngarna. De första studerades på glaskapillärkolonn, de andra på fylld kolonn, bägge med flamjonisationsdetektor.G a s k r o m a t o g r a f i s k a a n a 1 y s e r (performed on SI) Extraction with cyclohexane comprises non-polar compounds, followed by acidification and extraction with butyl acetate and derivatization with a trimethylsilyl reagent to determine the more polar compounds. The first were studied on a glass capillary column, the others on a filled column, both with a flame ionization detector.
Indunstningskondensat från l7.l0.79. I Mängden av både de opolära och de polära föreningarna var mycket starkt reducerad efter kondensatbehandlingen i oxidations- kolonnen. Huvudkomponenten av de opolära föreningarna var redu- 3 ppm). För de -v cerad ca. 20 ooo gånger (från 60 ppm till J- 10' polära föreningarna konstaterades en reduktion på ca 600 gånger för huvudkomponenten.Evaporation condensate from l7.l0.79. The amount of both the non-polar and the polar compounds was greatly reduced after the condensate treatment in the oxidation column. The major component of the non-polar compounds was redu- 3 ppm). For the -v cerad approx. 20,000 times (from 60 ppm to the J-10 'polar compounds, a reduction of about 600 times for the main component was observed.
Kokerikondensat från primo juni 1980 För de opolära föreningarna fann man en reduktion på ca 160 gånger. I den polära fraktionen påvisades icke några för- eningar i provet taget efter oxidatíonskolonnen, vilket motsva- rar minst 200 gångers reduktion när man beaktar detekterings- gränsen.Boiler condensate from the beginning of June 1980 A reduction of about 160 times was found for the non-polar compounds. In the polar fraction, no compounds were detected in the sample taken after the oxidation column, which corresponds to at least a 200-fold reduction when the detection limit is taken into account.
L u k t a n a 1 y s e r v i d h e a d - s p a c e - t e k n i k (utförda vid SI) Indunstningskondensatprovet från före och efter oxidations- kolonnen uppvärmdes 1 timme vid 40°C och gasen över vätskan (head-space) uttogs, koncentrerades på aktivt kol och analysera- des i gaskromatograf. Det uppges att det var mycket stor skillnad på proverna, då ca hälften av föreningarna från provet före oxi- dationen är borta i det från efter oxidationen. Totalinnehållet är ca 4 gånger större i det obehandlade. Några få nya flyktiga för- eningar tycks bildas, men dessa är närvarande i ytterst liten 10 9 462 169 mängd. Det synes i huvudsak röra sig om dimetyldisulfid.L u k t a n a 1 y s e r v i d h e a d - s p a c e - t e k n i k (performed at SI) The evaporation condensate sample from before and after the oxidation column was heated for 1 hour at 40 ° C and the gas over the liquid (head-space) was taken out, concentrated on activated carbon and analyzed by gas gas. It is stated that there was a very large difference in the samples, as about half of the compounds from the sample before the oxidation are missing in it from after the oxidation. The total content is about 4 times larger in the untreated. A few new volatile associations seem to be formed, but these are present in extremely small numbers. It seems to be mainly dimethyl disulfide.
A v d r i v n i n g a v m e t a n o l o c h s t u d i u m a V d e n n a s r e n h e t Metanol avdestillerades (utgjorde ca. 5 g/1) och analyse- rades på PFI's gaskromatograf. Kromatogrammen visade bara spår av en förening förutom metanol, och mängden av denna uppskatta- des till under 1,5 procent av metanolmängden.A v d r i v n i n g a v m e t a n o l o c h s t u d i u m a V d e n n a s r e n h e t Methanol was distilled off (amounting to approx. 5 g / l) and analyzed on PFI's gas chromatograph. The chromatograms showed only traces of a compound other than methanol, and the amount of this was estimated to be less than 1.5 percent of the amount of methanol.
K o a l e s c e n s Att koalescensfiltreringen var effektiv framgick av att 1) det samlas "olja" i toppen av enheten, och 2) kondensatet var ofta brungult före enheten och klart efter. Oljeinnehållet i obehandlat kondensat varierar inom mycket vida gränser.C o a l e s c e n s That the coalescence filtration was effective was evident from the fact that 1) "oil" accumulates at the top of the unit, and 2) the condensate was often brownish yellow before the unit and clear after. The oil content of untreated condensate varies within very wide limits.
LITTERATUR 1) Kirk Othmer: Encyclopedia of Chem . Te chn . 3. utg., vol. 4, s. 77-80 - Cellulose Preparation l. " " ll, s. 262-265 - Pulp. Sulfate Process 2) Pump and Paper: Chemistry and Chem. Techn. Ed.: J.P. Casey, 1980 a) 3. utg., vol. l, s. 475-76 - Treatment of Digester and Evaporator Condensates s. 1228-1229 - Kraft Mill Process b) 3' H II 2, Modifications 3) Vettenranta, I.: Enso-Biox Method.LITERATURE 1) Kirk Othmer: Encyclopedia of Chem. Te chn. 3rd ed., Vol. 4, pp. 77-80 - Cellulose Preparation l. "" Ll, pp. 262-265 - Pulp. Sulfate Process 2) Pump and Paper: Chemistry and Chem. Techn. Ed .: J.P. Casey, 1980 a) 3rd ed., Vol. l, pp. 475-76 - Treatment of Digester and Evaporator Condensates pp. 1228-1229 - Kraft Mill Process b) 3 'H II 2, Modifications 3) Vettenranta, I .: Enso-Biox Method.
Mill Condensates 1976 Intern. Environmental Improvement Conference Montreal 6.-8. okt. 1976 (Henviser til O. Koistinen, finsk patent 46497 av april 1973) 4) Smith, G.C. & Knowles, S.E. & Green, R.P.: (The Mead Corp.) Polysulfide Liquor Generation with MOXY System I 1974 TAPPI Alkaline Pulping Conference, Seattle 16.-18. sept. 1974 A Biological Method for Purifying Kraft Pulp S) Norsk pat.nr. 102 304 (beviljat 8. juni 1963).Mill Condensates 1976 Intern. Environmental Improvement Conference Montreal 6.-8. Oct 1976 (Referring to O. Koistinen, Finnish Patent 46497 of April 1973) 4) Smith, G.C. & Knowles, S.E. & Green, R.P .: (The Mead Corp.) Polysulfide Liquor Generation with MOXY System I 1974 TAPPI Alkaline Pulping Conference, Seattle 16.-18. sept. 1974 A Biological Method for Purifying Kraft Pulp S) Norsk pat.nr. 102,304 (granted June 8, 1963).
Claims (2)
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| NO811259A NO150971C (en) | 1981-04-10 | 1981-04-10 | PROCEDURE FOR CLEANING OF CONDENSATIVES FROM THE SULPHATE PROCESS |
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| SE462169B true SE462169B (en) | 1990-05-14 |
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| JP (1) | JPS57180484A (en) |
| CA (1) | CA1205930A (en) |
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| SE (1) | SE462169B (en) |
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| WO1996014464A1 (en) * | 1994-11-08 | 1996-05-17 | Kvaerner Pulping Ab | Odour treatment of malodorous condensates with ozone-containing residual gas |
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| FI128221B (en) * | 2015-04-27 | 2019-12-31 | Metsae Fibre Oy | Method for regenerating a catalyst used for producing polysulphide lye |
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| ZA737730B (en) * | 1972-10-26 | 1974-09-25 | St Regis Paper Co | Process for reducing the organic carbon content and improving the color of aqueous plant effluents |
| JPS5066480A (en) * | 1973-10-18 | 1975-06-04 | ||
| JPS562887A (en) * | 1979-06-20 | 1981-01-13 | Toshiba Corp | Treatment of waste alkali washing liquid for deodorizing |
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1981
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1982
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| WO1996014464A1 (en) * | 1994-11-08 | 1996-05-17 | Kvaerner Pulping Ab | Odour treatment of malodorous condensates with ozone-containing residual gas |
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| FI73254C (en) | 1987-09-10 |
| NO150971B (en) | 1984-10-08 |
| NO150971C (en) | 1985-01-23 |
| FI73254B (en) | 1987-05-29 |
| SE8202251L (en) | 1982-10-11 |
| CA1205930A (en) | 1986-06-10 |
| FI821271A0 (en) | 1982-04-08 |
| NO811259L (en) | 1982-10-11 |
| FI821271L (en) | 1982-10-11 |
| JPS57180484A (en) | 1982-11-06 |
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