EP0169305A2 - Process for purifying gases from pyrolysis installations of waste material - Google Patents

Process for purifying gases from pyrolysis installations of waste material Download PDF

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Publication number
EP0169305A2
EP0169305A2 EP85103522A EP85103522A EP0169305A2 EP 0169305 A2 EP0169305 A2 EP 0169305A2 EP 85103522 A EP85103522 A EP 85103522A EP 85103522 A EP85103522 A EP 85103522A EP 0169305 A2 EP0169305 A2 EP 0169305A2
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Prior art keywords
washing
gas
stage
water
washing stage
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German (de)
French (fr)
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EP0169305A3 (en
Inventor
Gebhard Dr. Bandel
Guido Engelke
Dirk Dr. Hankel
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KRAFTWERK UNION-UMWELTTECHNIK GMBH
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Kraftwerk Union-Umwelttechnik GmbH
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
    • C10K1/00—Purifying combustible gases containing carbon monoxide
    • C10K1/08—Purifying combustible gases containing carbon monoxide by washing with liquids; Reviving the used wash liquors
    • C10K1/10—Purifying combustible gases containing carbon monoxide by washing with liquids; Reviving the used wash liquors with aqueous liquids

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  • the invention relates to a method for cleaning gases containing combustible components from the pyrolysis of waste materials.
  • One method is that carbonization of the waste materials at temperatures of approximately 300 to 800 ° C. produces carbonization gases and a solid carbonization residue.
  • the carbonization gases are then cracked at higher temperatures of around 850 to 1200 ° C.
  • the cracked gases also contain toxic components such as NH 3 , HCN, H 2 S and COS in quantities that depend on the type of waste used.
  • the cracked gases must be freed from these components before they are burned. This happens in gas scrubbers.
  • Such methods are described for example in DE-PS 24 32 504, DE-OS 29 27 240, DE-AS 26 51 302, DE-AS 26 4 041, DE-OS 30 49 259, DE-OS 32 17 030.
  • the gas scrubbing is carried out by recycling with wash water containing Ca (OH) 2 .
  • wash water containing Ca (OH) 2 Only a few percent of the NH 3 and less than half of the H 2 S uno HCN are removed.
  • the object of the invention is to largely remove the toxic constituents from these gases and to convert them into forms which can be readily removed from the wash water.
  • the cooled raw gas 1 contains different contents of partially toxic components depending on the composition of the waste materials. For example, 1500 to 5000 mg NH 3 / NM 3 (based on dry gas), 200 to 1600 mg HCN / Nm 3 , 300 Lis 500 mg H 2 S / Nm 3 and 40 to 100 mg COS / N m 3 are included, which are particularly harmful and therefore must be largely removed.
  • water 3 and formalin 4 are injected and sprayed into the gas stream 1 in finely divided form.
  • the formalin is used, for example, in a concentration of about 37% by weight.
  • the HCN content of gas 1 is converted very quickly and largely to glyconitrile.
  • the NH 3 content is converted more slowly to hexamethylenetetramine.
  • the amount of formalin used is such that, in addition to the conversion of the HCN, at least the majority of the NH 3 is also converted.
  • water 7, alkali 8 and H 2 0 2 9 are injected or injected into the gas stream in finely divided form.
  • the amounts of lye and H 2 O 2 added are such that a pH of 8.5 to 9.5 is established in the scrubber 6 and the sulfur components H 2 S and COS contained in the gas 5 are largely dissolved and essentially closed Elemental sulfur are oxidized. In this pH range, a very good conversion is achieved with a relatively low consumption of reagents. Possibly. Traces of formaldehyde entering the second washing stage 6 with the gas 5 are eliminated by the H 2 O 2 .
  • the washing stages 2, 6 are advantageously operated with a circulation of the separated washing liquid 11, 12, an amount being withdrawn from the circuit which corresponds to the newly obtained amount of liquid.
  • the washing stages 2, 6 kc can be designed in one or more stages. The one drawn from the circuits of the first and second washing stages Washing liquid is passed into a cleaning system 11, in which the suspended substances are first removed and then the dissolved or chemically bound pollutants are converted into harmless compounds.
  • Ca (OH) 2 solution or lime milk is added, the Ca sulfate formed is removed with the suspended substances.
  • a preferred embodiment consists in that the pH is adjusted to 8.9 to 9.1 according to (d). Within this range, a particularly good implementation is achieved with a relatively low consumption of reagents.
  • a preferred embodiment consists of the washing liquid being circulated in (a) and (c).
  • a very good utilization of the reagents is achieved by the circulation, the content of reaction products in the washing liquid is increased and the amount of washing liquids led into the cleaning 11 is reduced.
  • the length L M of the washing water 3 in the circuit of the first washing stage 2 is either kept constant by the quantity of the condensed humidity of the gas or by addition of fresh water.
  • the liquid flowing out of the first washing stage is expediently passed into separators 12, in which the washed-out dust and condensed tars separate out.
  • the solution is pumped into the circuit and the sludge fraction 13 is passed into the water purification 11.
  • the amount of washing water in the circuit of the second washing stage is kept constant by adding water continuously or discontinuously.
  • a preferred embodiment is that the suspended conversion from the washing liquid according to (f) tion products 13 are separated, the remaining solution is treated with H 2 0 2 and lye in a first treatment stage 1 4, then treated in a second treatment stage 15 with further H 2 0 2 and heated to a maximum of 70 ° C. above 16 and then neutralized .
  • the suspended solids are separated off in a known manner, for example by flocculation, separation and filtration. NaOH solutions or Ca (OH) 2 solutions or lime milk or mixtures of these substances are used as lye. When Ca (OH) 2 solution or milk of lime is added, the poorly soluble Ca salt of glycolic acid precipitates.
  • the major part of the glyconitrile is converted to glycolic acid, the sulfur compounds to sulfate or elemental sulfur and the formaldehyde to Na or Ca formate by the H 2 0 2 .
  • the pH value is increased by the addition of lye and the reaction is improved by increasing the hydrolysis and oxidation potential.
  • the reaction is improved by increasing the hydrolysis and oxidation potential.
  • the conversion is optimized in the second treatment stage 15, so that no excess of H 2 O 2 has to be added in the first treatment stage 14.
  • the reaction is accelerated by the temperature increase in the second treatment stage. However, an increase above 70 ° C has a negative effect.
  • the neutralization 17 is generally carried out using sulfuric acid 18. After filtration, the solution of organic constituents contains only biodegradable compounds.
  • the advantages of the invention are that the cracked carbonization gases 1 are largely freed of harmful components, the washing water 3, 7 can also be largely freed of non-degradable components and the consumption of chemicals can be kept relatively low.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Treating Waste Gases (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

Such gases contain combustible constituents and a multiplicity of toxic constituents, which depend on the nature of the waste materials fed. Before combustion, the gases must be freed of these constituents. According to the invention, the crude gas is washed for this purpose in a first washing stage with water and formalin, the gas from the first washing stage is washed in a second washing stage with water, alkali and hydrogen peroxide, the pure gas is discharged from the second washing stage, and the suspended materials are removed from the washing liquids of the first and second washing stages and the reaction products dissolved in the washing liquids are converted for harmless use. The process according to the invention is especially suitable for use in pyrolysis plants.

Description

Die Erfindung betrifft ein Verfahren zur Reinigung von brennbare Bestandteile enthaltenden Gasen aus der Pyrolyse von Abfallstoffen.The invention relates to a method for cleaning gases containing combustible components from the pyrolysis of waste materials.

Die Beseitigung von organischen und anorganischen Abfallstoffen, wie Hausmüll, Industriemüll, Altreifen, Kunststoffabfällen, Klärschlamm oder dergl., in einer Weise, welche die Umweltbelastung möglichst gering hält, wird zu einem immer größeren und dringenderen Problem.The disposal of organic and inorganic waste materials, such as household waste, industrial waste, old tires, plastic waste, sewage sludge or the like, in a way that keeps the environmental impact as low as possible, is becoming an ever greater and more urgent problem.

Ein Verfahrensweg besteht darin, daß durch eine Verschwelung der Abfallstoffe bei Temperaturen von etwa 300 bis 800°C Schwelgase und ein fester Schwelrückstand erzeugt werden. Die Schwelgase werden anschließend bei höheren Temperaturen von etwa 850 bis 1200°C gekrackt. Die gekrackten Gase enthalten neben brennbaren Bestandteilen auch toxische Bestandteile wie NH3, HCN, H2S und COS in Mengen, die von der Art der eingesetzten Abfallstoffe abhs gig sind. Die gekrackten Gase müssen vor ihrer Ver- brenhung von diesen Bestandteilen befreit werden. Dies geschieht in Gaswäschern. Solche Verfahren sind z.B. beschrieben in der DE-PS 24 32 504, DE-OS 29 27 240, DE-AS 26 51 302, DE-AS 26 4 041, DE-OS 30 49 259, DE-OS 32 17 030. In der DE-OS 27 32 418 erfolgt die Gaswäsche durch Kreislaufführung mit Ca(OH)2 enthaltendem Waschwasser. Dabei werden jedoch nur wenige Prozente des NH3 und weniger als die Hälfte des H2S uno HCN entfernt.One method is that carbonization of the waste materials at temperatures of approximately 300 to 800 ° C. produces carbonization gases and a solid carbonization residue. The carbonization gases are then cracked at higher temperatures of around 850 to 1200 ° C. In addition to combustible components, the cracked gases also contain toxic components such as NH 3 , HCN, H 2 S and COS in quantities that depend on the type of waste used. The cracked gases must be freed from these components before they are burned. This happens in gas scrubbers. Such methods are described for example in DE-PS 24 32 504, DE-OS 29 27 240, DE-AS 26 51 302, DE-AS 26 4 041, DE-OS 30 49 259, DE-OS 32 17 030. In DE-OS 27 32 418, the gas scrubbing is carried out by recycling with wash water containing Ca (OH) 2 . However, only a few percent of the NH 3 and less than half of the H 2 S uno HCN are removed.

Der Erfindung liegt die Aufgabe zugrunde, die toxischen Bestandteile aus diesen Gasen weitgehend zu entfernen und in Formen zu überführen, die aus dem Waschwasser gut beseitigt werden können.The object of the invention is to largely remove the toxic constituents from these gases and to convert them into forms which can be readily removed from the wash water.

Die Lösung dieser Aufgabe erfolgt erfindungsgemäß dadurch, daß

  • a) das Rohgas 1 in einer ersten Waschstufe 2 mit Wasser 3 und Formalin (HCHO) 4 gewaschen wird,
  • b) die Zugabe an Formalin so eingestellt wird, daß neben weitgehender Umsetzung des Rohgas 1 enthaltenen HCN zu Glyconitril (CH2(OH) CN) mindestens der größte Teil des Ammoniak (NH3) zu Hexamethylentetramin (C 6 H 12 N 4) umgesetzt wird,
  • c) das Gas 5 aus der ersten Waschstufe 2 in einer zweiten Waschstufe 6 mit Wasser 7, Lauge 8 und H202 9 gewaschen wird,
  • d) der pH-Wert in der zweiten Waschstufe auf 8,5 bis 9,5 eingestellt wird,
  • e) das Reingas 10 aus der zweiten Waschstufe abgeleitet wird und
  • f) aus der Waschflüssigkeit 3/7 der ersten und zweiten Waschstufe die suspendierten Stoffe entfernt werden und die in der Waschflüssigkeit gelösten Umsetzungsprodukte in unschädliche Verbindungen umgesetzt werden.
This object is achieved in that
  • a) the raw gas 1 is washed in a first washing stage 2 with water 3 and formalin (HCHO) 4,
  • b) the addition of formalin is adjusted such that, in addition to largely converting the raw gas 1 contained HCN to glyconitrile (CH 2 (OH) CN), at least the majority of the ammonia (NH 3 ) is converted to hexamethylenetetramine ( C 6 H 12 N 4 ) becomes,
  • c) the gas 5 from the first washing stage 2 is washed in a second washing stage 6 with water 7, alkali 8 and H 2 0 2 9,
  • d) the pH in the second washing stage is adjusted to 8.5 to 9.5,
  • e) the clean gas 10 is derived from the second washing stage and
  • f) the suspended substances are removed from the washing liquid 3/7 of the first and second washing stage and the reaction products dissolved in the washing liquid are converted into harmless compounds.

Das gekühlte Rohgas 1 enthält je nach Zusammensetzung der Abfallstoffe unterschiedliche Gehalte an zum Teil toxischen Bestandteilen. So können z.B. 1500 bis 5000 mg NH3/NM3 (bezogen auf trockenes Gas), 200 bis 1600 mg HCN/Nm3, 300 Lis 500 mg H2S/Nm3 und 40 bis 100 mg COS/ Nm3 enthalten sein, die besonders schädlich sind und deshalb weitgehend entfernt werden müssen. In der ersten Waschstufe 2 werden in den Gasstrom 1 Wasser 3 und Formalin 4 in feinverteilter Form eingedüst und gesprüht. Das Formalin wird z.B. in einer Konzentration von etwa 37 Gew.% eingesetzt. Dabei wird der HCN-Gehalt des Gases 1 sehr schnell und weitgehend zu Glyconitril umgesetzt. Die Umsetzung des NH3-Gehaltes zu Hexamethylentetramin erfolgt langsamer. Die Menge des eingesetzten Formalin wird so bemessen, daß neben der Umsetzung des HCN auch mindestens der größte Teil des NH3 umgesetzt wird. In der zweiten Waschstufe 6 werden in den Gasstrom Wasser 7, Lauge 8 und H202 9 in feinverteilter Form eingedüst oder eingespritzt. Die zugegebenen Mengen an Lauge und H202 werden so bemessen, daß sich im Wäscher 6 ein pH-Wert von 8,5 bis 9,5 einstellt und die im Gas 5 enthaltenen Schwefelkomponenten H2S und COS weitgehend gelöst und im wesentlichen zu Elementarschwefel oxidiert werden. In diesem pH-Bereich wird eine sehr gute Umsetzung bei relativ niedrigem Verbrauch an Reagenzien erzielt. Evtl. in die zweite Waschstufe 6 mit dem Gas 5 eintretende Spuren von Formaldehyd werden durch das H202 beseitigt. Als Lauge 8 werden NaOH-Lösungen hzw. Kalkmilch oder Gemische dieser Stoffe eingesetzt. Bei der Zugabe von Ca(OH)2-Lösung bzw. Kalkmilch werden evtl. gebildete Sulfate in schwerlösliches Ca-Sulfat umgewandelt. Die Waschstufen 2, 6 werden vorteilhafterweise mit einer Kreislaufführung der abgeschiedenen Waschflüssigkeit 11, 12 betrieben, wobei aus dem Kreislauf eine Menge abgezogen wird, die der neu anfallenden Menge an Flüssigkeit entspricht. Die Waschstufen 2, 6 kc nen ein- oder mehrstufig ausgebildet sein. Die aus den Kreisläufen der ersten und zweiten Waschstufe abgezogene Waschflüssigkeit wird in eine Reinigung 11 geleitet, in der zunächst die suspendierten Stoffe entfernt werden und dann die gelösten bzw. chemisch gebundenen Schadstoffe in unschädliche Verbindungen umgesetzt werden. Bei der Zugabe von Ca(OH)2-Lösung bzw. Kalkmilche wird das gebildete Ca-Sulfat mit den suspendierten Stoffen entfernt.The cooled raw gas 1 contains different contents of partially toxic components depending on the composition of the waste materials. For example, 1500 to 5000 mg NH 3 / NM 3 (based on dry gas), 200 to 1600 mg HCN / Nm 3 , 300 Lis 500 mg H 2 S / Nm 3 and 40 to 100 mg COS / N m 3 are included, which are particularly harmful and therefore must be largely removed. In the first washing stage 2, water 3 and formalin 4 are injected and sprayed into the gas stream 1 in finely divided form. The formalin is used, for example, in a concentration of about 37% by weight. The HCN content of gas 1 is converted very quickly and largely to glyconitrile. The NH 3 content is converted more slowly to hexamethylenetetramine. The amount of formalin used is such that, in addition to the conversion of the HCN, at least the majority of the NH 3 is also converted. In the second washing stage 6, water 7, alkali 8 and H 2 0 2 9 are injected or injected into the gas stream in finely divided form. The amounts of lye and H 2 O 2 added are such that a pH of 8.5 to 9.5 is established in the scrubber 6 and the sulfur components H 2 S and COS contained in the gas 5 are largely dissolved and essentially closed Elemental sulfur are oxidized. In this pH range, a very good conversion is achieved with a relatively low consumption of reagents. Possibly. Traces of formaldehyde entering the second washing stage 6 with the gas 5 are eliminated by the H 2 O 2 . As lye 8 NaOH solutions are hzw. Lime milk or mixtures of these substances are used. When Ca (OH) 2 solution or milk of lime is added, any sulfates formed are converted into poorly soluble Ca sulfate. The washing stages 2, 6 are advantageously operated with a circulation of the separated washing liquid 11, 12, an amount being withdrawn from the circuit which corresponds to the newly obtained amount of liquid. The washing stages 2, 6 kc can be designed in one or more stages. The one drawn from the circuits of the first and second washing stages Washing liquid is passed into a cleaning system 11, in which the suspended substances are first removed and then the dissolved or chemically bound pollutants are converted into harmless compounds. When Ca (OH) 2 solution or lime milk is added, the Ca sulfate formed is removed with the suspended substances.

Eine vorzugsweise Ausgestaltung besteht darin, daß der pH-Wert gemäß (d) auf 8, 9 bis 9,1 eingestellt wird. Innerhalb dieses Bereiches wird eine besonders gute Umsetzung bei relativ niedrigem Verbrauch an Reagenzien erzielt.A preferred embodiment consists in that the pH is adjusted to 8.9 to 9.1 according to (d). Within this range, a particularly good implementation is achieved with a relatively low consumption of reagents.

Eine vorzugsweise Ausgestaltung besteht darin, daß die Waschflüssigkeit in (a) und (c) im Kreislauf geführt weraen. Durch die Kreislaufführung wird eine sehr gute Ausnutzung der Reagenzien erzielt, der Gehalt der Waschflüssigkeit an Umsetzungsprodukten wird erhöht und die Menge der in die Reinigung 11 geleiteten Waschflüssigkeiten wird verringert. Die MLnge des Waschwassers 3 im Kreislauf der ersten Waschstufe 2 wird entweder durch die Menge der kondensierten Feuchtigkeit des Gases oder durch Zugabe von frischem Wasser konstant gehalten. Die aus der ersten Waschstufe ablaufende Flüssigkeit wird zweckmäßigeiweise in Separatoren 12 geleitet, in denen sich der ausgewaschene Staub und auskondensierte Teere abscheiden. Die Lösung wird in den Kreislauf gepumpt und die Schlammfraktion 13 in die Wasserreinigung 11 geleitet. Die Menge des Waschwassers im Kreislauf der zweiten Waschstufe wird durch kontinuierliche oder diskontinuierliche Wasserzugabe konstant gehalten.A preferred embodiment consists of the washing liquid being circulated in (a) and (c). A very good utilization of the reagents is achieved by the circulation, the content of reaction products in the washing liquid is increased and the amount of washing liquids led into the cleaning 11 is reduced. The length L M of the washing water 3 in the circuit of the first washing stage 2 is either kept constant by the quantity of the condensed humidity of the gas or by addition of fresh water. The liquid flowing out of the first washing stage is expediently passed into separators 12, in which the washed-out dust and condensed tars separate out. The solution is pumped into the circuit and the sludge fraction 13 is passed into the water purification 11. The amount of washing water in the circuit of the second washing stage is kept constant by adding water continuously or discontinuously.

Eine vorzugsweise Ausgestaltung besteht darin, daß aus der Waschflüssigkeit gemäß (f) die suspendierten Umsetzungsprodukte 13 abgetrennt werden, die restliche Lösunmit H202 und Lauge in einer ersten Behandlungsstufe 14 behandelt wird, dananch in einer zweiten Behandlungsstufe 15 mit weiterem H202 behandelt und über 16 maximal auf 70°C aufgeheizt wird und anschließend neutralisiert wird. Die Abtrennung der suspendierten Feststoffe erfolgt in bekannter Weise z.B. durch Flockung, Abtrennung und Filtration. Als Lauge werden NaOH-Lösungen oder Ca(OH)2-Lösungen bzw. Kalkmilch oder Gemische dieser Stoffe eingesetzt. Bei der Zugabe von Ca(OH)2-Lösung bzw. Kalkmilch fällt das schwerlösliche Ca-Salz der Glycolsäure aus. In der ersten Behandlungsstufe 14 wird durch das H202 der überwiegende Teil des Glyconitril zu Glycolsäure, der Schwefelverbindungen zu Sulfat bzw. elementarem Schwefel und das Formaldehyd zu Na- bzw. Ca-Formiat umgesetzt. Durch die Zugabe von Lauge wird der pH-Wert erhöht und die Umsetzung durch Erhöhung des Hydrolyse-und Oxidationspotentials verbessert. In der zweiten Behandlungsstufe 15 wird die Umsetzurgdurch Erhöhung des Hydrolyse- und Oxidationspotentials verbessert. In der zweiten Behandlungsstufe 15 wird die Umsetzung optimiert, wodurch in der ersten Behandlungsstufe 14 kein Überschuß an H202 zugegeben werden muß. Durch die Temperaturerhöhung in der zweiten Behandlungsstufe wird die Reaktion beschleunigt. Eine Erhöhung über 70°C ergibt jedoch einer negativen Effekt. Die Neutralisation 17 erfolgt im allgemeinen mit Schwefelsäure 18. Nach einer Filtration enthält die Lösung an organischen Bestandteilen nur biologisch abbaubare Verbindungen.A preferred embodiment is that the suspended conversion from the washing liquid according to (f) tion products 13 are separated, the remaining solution is treated with H 2 0 2 and lye in a first treatment stage 1 4, then treated in a second treatment stage 15 with further H 2 0 2 and heated to a maximum of 70 ° C. above 16 and then neutralized . The suspended solids are separated off in a known manner, for example by flocculation, separation and filtration. NaOH solutions or Ca (OH) 2 solutions or lime milk or mixtures of these substances are used as lye. When Ca (OH) 2 solution or milk of lime is added, the poorly soluble Ca salt of glycolic acid precipitates. In the first treatment stage 14, the major part of the glyconitrile is converted to glycolic acid, the sulfur compounds to sulfate or elemental sulfur and the formaldehyde to Na or Ca formate by the H 2 0 2 . The pH value is increased by the addition of lye and the reaction is improved by increasing the hydrolysis and oxidation potential. In the second treatment stage 15, the reaction is improved by increasing the hydrolysis and oxidation potential. The conversion is optimized in the second treatment stage 15, so that no excess of H 2 O 2 has to be added in the first treatment stage 14. The reaction is accelerated by the temperature increase in the second treatment stage. However, an increase above 70 ° C has a negative effect. The neutralization 17 is generally carried out using sulfuric acid 18. After filtration, the solution of organic constituents contains only biodegradable compounds.

In der Gaswäsche wird ein Gesamtabscheidegrad erzielt

Figure imgb0001
Das Verfahren ist in dem Fließschema dargestellt.A total degree of separation is achieved in gas scrubbing
Figure imgb0001
 The process is shown in the flow diagram.

Die Vorteile der Erfindung bestehen darin, daß die gekrackten Schwelgase 1 weitgehendst von schädlichen Bestandteilen befreit werden, das Waschwasser 3, 7 ebenfalls weitgehendst von nicht abbaubaren Bestandteilen befreit werden kann und der Verbrauch an Chemikalien relativ gering gehalten werden kann.The advantages of the invention are that the cracked carbonization gases 1 are largely freed of harmful components, the washing water 3, 7 can also be largely freed of non-degradable components and the consumption of chemicals can be kept relatively low.

Bezugszeichenliste (VPA 84 P 8533 DE)List of reference symbols (VPA 84 P 8533 DE)

  • Rohgas 1Raw gas 1
  • erste Waschstufe 2first washing stage 2
  • Wasser (H20) 3Water (H 2 0) 3
  • Formalin (HCHO) 4Formalin (HCHO) 4
  • Gas 5Gas 5
  • zweite Waschstufe 6second washing stage 6
  • Wasser 7Water 7
  • Lauge 8Alkali 8
  • Wasserstoffsuperoxyd 9Hydrogen superoxide 9
  • Reingas 10Clean gas 10
  • Reinigung 11Cleaning 11
  • Seperator 12Seperator 12
  • Schlammfraktion 13Sludge fraction 13
  • erste Behandlungsstufe 14first treatment stage 14
  • zweite Behandlungsstufe 15second treatment stage 15
  • Wärme 16Warmth 16
  • Neutralisationsstufe 17Neutralization level 17
  • Säure 18Acid 18

Claims (4)

1. Verfahren zur Reinigung von brennbare Bestandteile enthaltenden Gasen aus der Pyrolyse von Abfallstoffen, dadurch gekennzeichnet, daß a) das Gas (1) in einer ersten Waschstufe (2) mit Wasser (3) und Formalin (HCHO) (4) gewaschen wird, b) die Zugabe an Formalin so eingestellt wird, daß neben weitgehender Umsetzung des im Gas (1) enthaltenen HCN zu Glyconitril (CH2(OH) CN) mindestens der größte Teil des Ammoniak (NH3) zu Hexamethylentetramin (C6H12N4) umgesetzt wird, c) das Gas (5) aus der ersten Waschstufe (2) in einer zweiten Waschstufe (6) mit Wasser (7), Lauge (8) und H2O2 (9) gewaschen, d) der pH-Wert in der zweiten Waschstufe (6) auf 8,5 bis 9,5 eingestellt wird, e) das Reingas (10) aus der zweiten Waschstufe (6) abgeleitet wird und f) aus der Waschflüssigkeit (3/7) der ersten und zweiten Waschstufe (2, 6) die suspendierten Stoffe (13) entfernt werden und die in der Waschflüssigkeit gelösten Umsetzungsprodukte in undschädliche Verbindungen umgesetzt werden. 1. A process for the purification of flammable constituent gases from the pyrolysis of waste materials, characterized in that a) the gas (1) is washed in a first washing stage (2) with water (3) and formalin (HCHO) (4), b) the addition of formalin is adjusted such that in addition to the extensive conversion of the HCN contained in the gas (1) to glyconitrile (CH 2 (OH) CN) at least the largest part of the ammonia (NH 3 ) to hexamethylenetetramine (C 6 H 12 N 4 ) is implemented, c) the gas (5) from the first washing stage (2) is washed in a second washing stage (6) with water (7), lye (8) and H 2 O 2 (9), d) adjusted) of the p H value in the second washing stage (6 to 8.5 to 9.5, e) the clean gas (10) is derived from the second washing stage (6) and f) the suspended substances (13) are removed from the washing liquid (3/7) of the first and second washing stages (2, 6) and the reaction products dissolved in the washing liquid are converted into noxious compounds. 2. Verfahren nach Anspruch 1,
dadurch gekennzeichnet,
daß der pH-Wert gemäß (d) auf 8,9 bis 9,1 eingestellt wird.2. The method according to claim 1,
characterized,
that the pH according to (d) is adjusted to 8.9 to 9.1. 3. Verfahren nach Anspruch 1 oder 2,
dadurch gekennzeichnet ,
daß die Waschflüssigkeiten (3, 7) in (a) und (c) im Kreislauf geführt werden.3. The method according to claim 1 or 2,
characterized ,
that the washing liquids (3, 7) in (a) and (c) are circulated. 4. Verfahren nach einem der Ansprüche 1 bis 3,
dadurch gekennzeichnet ,
daß aus der Waschflüssigkeit gemäß (f) die suspendierten Umsetzungsprodukte (13) abgetrennt werden, die restliche Lösung mit H202 (9) und Lauge (8) in einer ersten Behandlungsstufe (14) behandelt wird, danach in einer zweiten Behandlungsstufe (15) mit weiterem H202 (9) behandelt und maximal auf 70°C aufgeheizt wird und anschließend neutralisiert (18, 19) wird.4. The method according to any one of claims 1 to 3,
characterized ,
that the suspended reaction products (13) are separated from the washing liquid according to (f), the remaining solution is treated with H 2 O 2 (9) and lye (8) in a first treatment stage (14), then in a second treatment stage (15 ) treated with further H 2 0 2 (9) and heated to a maximum of 70 ° C and then neutralized (18, 19).
EP85103522A 1984-04-04 1985-03-25 Process for purifying gases from pyrolysis installations of waste material Ceased EP0169305A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843412581 DE3412581A1 (en) 1984-04-04 1984-04-04 METHOD FOR PURIFYING GAS FROM PYROLYSIS PLANTS OF WASTE
DE3412581 1984-04-04

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EP0169305A2 true EP0169305A2 (en) 1986-01-29
EP0169305A3 EP0169305A3 (en) 1988-03-23

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EP85103522A Ceased EP0169305A3 (en) 1984-04-04 1985-03-25 Process for purifying gases from pyrolysis installations of waste material

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EP (1) EP0169305A3 (en)
DE (1) DE3412581A1 (en)
FI (1) FI77259C (en)
IL (1) IL74798A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0223904A2 (en) * 1985-09-28 1987-06-03 Degussa Aktiengesellschaft Process for purifying an industrial or a flue gas
EP0514673A1 (en) * 1991-05-23 1992-11-25 Degussa Aktiengesellschaft Process for the separation of hydrogen cyanide from gases and waste gases

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2740355B1 (en) * 1995-10-27 1998-01-16 Cos Ingenierie PROCESS FOR AMMONIACAL DEPOLLUTION OF LIQUID OR GASEOUS EFFLUENTS
ATE230789T1 (en) * 1996-10-29 2003-01-15 Thermoselect Ag METHOD FOR COMPLETE MATERIAL, EMISSION-FREE USE THROUGH HIGH TEMPERATURE RECYCLING AND THROUGH FRACTIONAL MATERIAL-SPECIFIC CONVERSION OF THE RESULTING SYNTHESIS RAW GAS
DE102008018698A1 (en) 2008-04-09 2009-10-22 Durtec Gmbh New mineral gas adsorber for biogas plants
DE102011010525A1 (en) 2011-02-08 2012-08-09 Universität Rostock Process for the purification of biogas, flue gas or liquids, adsorbent therefor, filters, and use of the adsorbent

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE412113C (en) * 1922-03-03 1925-04-15 Hermann Rathert Dr Process for the destruction of carbon disulfide in exhaust gases
US2859090A (en) * 1955-02-07 1958-11-04 Exxon Research Engineering Co Treatment of fluids for removal of hydrogen cyanide
FR2267984A1 (en) * 1974-04-22 1975-11-14 Degussa

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE412113C (en) * 1922-03-03 1925-04-15 Hermann Rathert Dr Process for the destruction of carbon disulfide in exhaust gases
US2859090A (en) * 1955-02-07 1958-11-04 Exxon Research Engineering Co Treatment of fluids for removal of hydrogen cyanide
FR2267984A1 (en) * 1974-04-22 1975-11-14 Degussa

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
CHEMISTRY AND INDUSTRY, Nr. 14, Juli 1983, Seiten 555-558, London, GB; A.F.E. SIMS: "Industrial effluent treatment with hydrogen peroxide" *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0223904A2 (en) * 1985-09-28 1987-06-03 Degussa Aktiengesellschaft Process for purifying an industrial or a flue gas
EP0223904A3 (en) * 1985-09-28 1988-04-13 Degussa Aktiengesellschaft Process for purifying an industrial or a flue gas
EP0514673A1 (en) * 1991-05-23 1992-11-25 Degussa Aktiengesellschaft Process for the separation of hydrogen cyanide from gases and waste gases
US5200161A (en) * 1991-05-23 1993-04-06 Degussa Aktiengesellschaft Process for the separation of hydrogen cyanide from gases and waste gases

Also Published As

Publication number Publication date
FI850678L (en) 1985-10-05
FI77259B (en) 1988-10-31
EP0169305A3 (en) 1988-03-23
FI77259C (en) 1989-02-10
IL74798A0 (en) 1985-07-31
FI850678A0 (en) 1985-02-19
DE3412581A1 (en) 1985-10-24
IL74798A (en) 1988-09-30

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