EP0526956B1 - Method for treatment of primers containing mercury compounds, potassium chlorate and antimony trisulphide - Google Patents

Abstract

The invention relates to a method for reprocessing mercury compound-, potassium chlorate- and antimony trisulphide-containing detonators of cartridges and similar assemblies of military products by converting the initial explosive contained therein into inert non-ignitable compounds or substances and by conversions of the potassium chlorate, contained in the priming composition and serving as oxygen carrier, into potassium chloride. The process according to the invention has the following advantages: - the absolutely safe quantitative conversion of the explosive, - the greatest possible matching to the dismantling method, - universal applicability, - no additional use of environmentally polluting auxiliaries, - very few technological steps, - simple handling and - retention of the metallic state of the brass caps.

Description

The invention relates to a method for the preparation of mercury compounds, potassium chlorate and antimony trisulfide containing primers of cartridges and similar assemblies of military products. The treatment process removes the ignition effect of primers in primers and similar assemblies by converting the initial explosive contained in inert, non-ignitable compounds or substances and by converting the potassium chloride contained in the primer, which serves as an oxygen carrier, into potassium chloride.

The invention thus relates primarily to the field of military technology and relates to the desensitization of detonators, such as those used in primers, ignition screws, detonating devices and chemical initiators of various ammunition, locking and clearing agents, for the purpose of safely removing such military products, to ensure the safe transportation of assemblies containing such primers, as well as the safe processing of these mixtures or assemblies and products.

CS-A 267 047 describes the recovery of mercury from mercury-fulminate waste from explosives. The waste is reacted in a water suspension with Mg powder. The Mg / Hg ratio is (1 to 5) to 10. The Mg fulminate obtained and the excess Mg are concentrated using a Mineral acid, especially HCL, decomposes, and the mercury is separated.

Derwent Publication Ltd., London, GB, AN 85-319 723 describes the disposal of waste water containing mercury. The mercury ions to the metal are reduced by adding an iron solution, adjusting the pH and aerating.

JP-A-60 222 190 also describes the disposal of waste water containing mercury. A solution containing iron ions is added to the waste water. The pH is adjusted to 10 to 12 with an alkaline solution. The reaction, which is constantly ventilated, produces Hg ferrite. The mercury ions in the water are reduced to metallic mercury by reducing agents.

Another process for removing mercury and mercury salts from aqueous liquids is described in DE-0S 392 0487. By precipitation with formamidine sulfinic acid and filtration, with the addition of filter aids, mercury-containing aqueous liquids can be freed of mercury and mercury salts to such an extent that the mercury content of the purified aqueous liquids is below the detection limit of 0.004 mg / l.

• Vernichtung der Zündhütchen und Zünderbaugruppen durch Sprengen, Verbrennen oder Ausbrennen unter Sicherheitsmaßnahmen. Diese Art der Aufbereitung ist mit Luftverunreinigung verbunden.
• Teilphlegmatisierung von Ausschußteilen aus dem Herstellungsprozeß mittels Öl oder ähnlichen Medien , um einen ruhigen Abbrand zu erreichen.
• Zündsatz im unverpreßten Zustand wird durch Einrühren in Natriumthiosulfatlösung oder durch Hydrolyse in stark basischem Medium bei 100 °C gespalten.

The following methods are known in the field of phlegmatization and desensitization of primers in primers and similar assemblies:

• Destruction of the primers and fuse assemblies by blasting, burning or burning out under safety measures. This type of treatment is associated with air pollution.
• Partial phlegmatization of rejects from the manufacturing process using oil or similar media in order to achieve a smooth burn-up.
• Primer in the uncompressed state is split by stirring in sodium thiosulfate solution or by hydrolysis in a strongly basic medium at 100 ° C.

The resulting degradation products must in any case be sent to a special waste landfill or pollute the user due to environmental damage in the form of wastewater pollution or contamination of scrap, earth, etc.

• sie sind für die Bearbeitung größerer Mengen von Zündsätzen in Zündhütchen und ähnlichen Baugruppen zu zeitaufwendig,
• sie führen zu unerwünschten chemischen Nebenprodukten,
• sie bieten keine ausreichende Sicherheit bezüglich der gewünschten, vollständigen Umwandlung der enthaltenen Initialsprengstoffe und sprengfähigen Gemische in inerte Verbindungen und die Überführung des im Zündsatz enthaltenen Kaliumchlorats in Kaliumchlorid.

The application of the known methods for the desensitization and desensitization of primers essentially leads to the following disadvantages:

• they are too time-consuming to process large quantities of primers in primers and similar assemblies,
• they lead to unwanted chemical by-products,
• they do not offer sufficient security with regard to the desired, complete conversion of the initial explosives and explosive mixtures contained inert compounds and the conversion of the potassium chlorate contained in the primer into potassium chloride.

With the removal of ammunition from the stocks of the CMEA countries, in particular the former NVA, there is also the task of disposing of mercury-containing primers and ignition assemblies.

The aim of the invention is to find an economically justifiable and reliable process alternative for canceling the ignition effect of primers in primers and assemblies or products of a similar purpose and thus to enable their safe transport and rational processing.

The invention has for its object to find a simple, safe and rational method for desensitizing large quantities of primers and similar assemblies based on primers containing mercury fulminate and thus to enable the environmentally friendly disposal of this mercury-containing waste from ammunition development.

The primary task for the environmentally friendly disposal of the mercury-containing primers was to remove the ignition effect by chemical conversion of the explosives contained. Subsequent demercurization of the resulting mercury-containing waste is possible with the current state of the art.

Surprisingly, it has now been found that with the help of water or an aqueous solution of alkaline ingredients and in the presence of iron, redox reactions are initiated, which in particular if the water or the aqueous solution of alkaline ingredients come into contact with the primer, the rapid conversion of the contained ingredients Initiate explosive mercury fulminate into an inert, non-ignitable mercury compound or metallic mercury and at the same time lead the remaining ignitable and initiable potassium chlorate-antimony trisulfide mixture by converting the potassium chlorate into potassium chloride to form an ignitable mixture of substances.

• a) die in Patronenhülsen befindlichen Zündhütchen in einem Wasserbad z.B. bei Temperaturen von 70 bis 100° C in einem Zeitraum von 30 min bis zu 4 h, vorbehandelt werden, wobei die Temperatur und die Zeit frei wählbar sind,
• b) die so vorbehandelten Patronenhülsen mit Zündhütchen einer Nachbehandlung zur Verdampfung des Restwassers und zur Auflockerung der kristallinen Struktur des Quecksilberfulminats bei einer Temperatur zwischen 80 und max. 142° C in 30 bis 60 min unterzogen werden, wobei bei Temperaturen über 110° C die Umwandlung des Quecksilberfulminats in Pyrofulmin eingeleitet wird,
• c) die in den Boden der Patronenhülsen eingepreßten Zündhütchen mechanisch von den Patronenhülsen innerhalb von etwa 3 bis 12 h nach Abschluß des in b) beschriebenen Vorgangs abgetrennt werden,
• d) danach die Zündhütchen mit fein verteiltem Eisen bzw. korrisionsfähigen Eisenwerkstoffen vermischt und anschließend mit Wasser oder einer wäßrigen Lösung alkalisch wirkender Ingredientien übergossen werden, wobei die Menge des Mediums so gewählt ist, daß sie die Zündhütchen und das Eisen bedeckt,
• e) der Ansatz solange stehen bleibt, bis der Zündsatz in den Zündhütchen vollständig vom Wasser oder der wäßrigen Lösung alkalisch wirkender Ingredientien durchdrungen ist und das in Lösung gegangene Kalichlorat das Eisen oxidiert und sich zu Kaliumchlorid und die Eisenionen die Quecksilberverbinddungen in inerte Quecksilberverbindungen bzw. metallisches Quecksilber umgewandelt hat,
• f) die entstandenen quecksilberhaltigen Reststoffe aufgearbeitet werden.

The solution according to the invention is achieved in that

• a) the primers in the cartridge cases are pretreated in a water bath, for example at temperatures from 70 to 100 ° C. in a period from 30 minutes to 4 hours, the temperature and the time being freely selectable,
• b) the cartridge cases pretreated in this way with primers of a post-treatment to evaporate the residual water and to loosen the crystalline structure of the mercury fullminate at a temperature between 80 and max. 142 ° C in 30 to 60 min, whereby at temperatures above 110 ° C the conversion of mercury fullminate into pyrofulmin is initiated,
• c) the primers pressed into the bottom of the cartridge cases are mechanically separated from the cartridge cases within approximately 3 to 12 hours after the process described in b) has been completed,
• d) then the primers are mixed with finely divided iron or iron materials capable of being corrected and then poured over with water or an aqueous solution of alkaline ingredients, the amount of medium being chosen so that it covers the primers and the iron,
• e) the batch remains until the primer in the primer is completely permeated with water or the aqueous solution of alkaline ingredients and the dissolved potassium chloride oxidizes the iron and the mercury compounds become potassium chloride and the iron ions in inert mercury compounds or metallic Mercury has converted
• f) the resulting mercury-containing residues are worked up.

• der beim Ausstoßen der Zündhütchen ebenfalls freigesetzte Amboß der Patronenhülse als Eisenbestandteil verwendet wird,
• das Eisen nach dem Demercurisierungsprozeß durch magnetische Abtrennung zurückgewonnen und wieder als Reduktionsmittel eingesetzt wird,
• als wäßrige Lösung alkalisch wirkender Ingredientien z.B. Seife, Natronlauge oder andere verwendet werden.

Particularly preferred embodiments of the method according to the invention are characterized in that

• the anvil of the cartridge case which is also released when the primers are ejected is used as an iron component,
• the iron is recovered by magnetic separation after the demercurization process and is used again as a reducing agent,
• as an aqueous solution of alkaline ingredients such as soap, sodium hydroxide or others can be used.

• a) längeres Aufbewahren in neutraler wäßriger Lösung,
• b) längeres Aufbewahren in alkalischer wäßriger Lösung und
• c) Einwirken verschiedener Reduktionsmittel in wäßriger Lösung.

The primer charge of the primers to be prepared consists of 25% mercury fulminate as the primer and 37.5% potassium chlorate and antimony trisulfide as a carrier for the propellant charge. The primers are covered with special paper, varnish or Sn foil to protect them against moisture penetration. In order to initiate a chemical reaction, the protective effect of the cover must first be removed. This had a favorable effect on the fact that when the cartridges were originally installed and when they were dismantled, considerable mechanical effects on the cover occur. In addition, the cartridge cases are treated with hot water before the primers are ejected to temporarily desensitize the primer. The investigations into the conversion of the explosives were carried out in three directions:

• a) longer storage in neutral aqueous solution,
• b) longer storage in alkaline aqueous solution and
• c) exposure to various reducing agents in aqueous solution.

To a)

The simple watering of the primer does not lead to success even after several weeks, since the KClO₃ is gradually removed from the primer and oxidizes the brass bowl, but the Hg fulminate remains unchanged and is explosive after drying.

To b)

In alkaline aqueous solution, in addition to dissolving the KClO₃ and the associated attack on the brass, the hydrolytic decomposition of the Hg fulminate to HgO and various gaseous, partly water-soluble products (CO₂, N₂, NH₃) succeeds. Potassium chlorate that is not fully converted leads to deflagration in the subsequent thermal treatment, while HgO causes complications during the preparation.

To c)

The described negative phenomena made the use of reducing agents appear appropriate. The electrolytic reduction of mercury fulminate and potassium chlorate is possible, but would have required additional technical and technological effort in the delamination companies.

In order to avoid additional stress on the treatment solution and the associated difficulties in the final wastewater disposal, hydrazine compounds and metallic iron were tested in a neutral and alkaline aqueous environment.

While hydrazine or hydrazine compounds alone did not show comprehensive positive results, the use of iron in neutral and also alkaline aqueous solution brought the surprising success. The use of Fe is with a noticeable increase in amounts to be managed, but the achievable safety in the removal of the explosives is of crucial importance for compliance with the legal provisions.

The technical implementation of the addition of iron or corrosion-resistant iron materials is therefore particularly advantageous since the so-called anvil is also ejected when the primers are ejected from the bottom of the cartridge case. Originally it was planned to hold this steel point by magnetic separation. This technological step can now be omitted. In brass cartridge cases, Fe is added by adding finely divided iron.

Ausgangsstoffe:

Wasser, Messing CuZn3O, Kaliumchlorat, Antimontrisulfid, Hg-Fulminat, Eisen, teilweise Zinn

Endprodukte:

Metallisches Hg, Amalgame, Fe₂O₃, Cu-Ionen, Zn-Ionen, Cl-Ionen, Cu, Cu zementiert an Fe, CuZn3O, unzersetztes Fe, CuO, Sb.

Kaliumchlorat geht in Lösung und wirkt als Oxidationsmittel, der erste Angriff gilt dem metallischen Fe unter Bildung von Fe(III)oxid:



        (2)   ClO₃⁻ + 2 Fe → Cl⁻ + Fe₂O₃



Fortschreitend entstehen intermediär Fe(II)-Ionen



        (3)   ClO₃⁻ + 3 Fe → Cl⁻ + 3 FeO



Die Fe(II)-Ionen wirken reduzierend auf das Hg-Fulminat ein und zerstören es unter der Bildung von metallischem Quecksilber



        (4)   2 Fe⁺⁺ + Hg⁺⁺ → Hg + 2 Fe⁺⁺⁺



Analysen zeigten, daß in den wäßrigen Lösungen das Verhältnis von Cu- zu Zn-Ionen nicht dem Verhältnis der beiden Metalle in der Legierung CuZn3O entspricht, sondern ein hoher Überschuß an Cu-Ionen auftritt. Es ist deshalb anzunehmen, daß das metallische Quecksilber vorzugsweise Zn-Amalgam bildet und das dabei entehende feinverteilte Kupfer durch Chlorat zu Cu⁺ oxidiert wird:



        (5)   6 Cu + ClO₃⁻ → 3 Cu₂O + Cl⁻





        (6)   3 Cu₂O + ClO₃⁻ → 6 CuO + Cl⁻



Reaktion (6) wurde erst nach dem Abtrennen der Cu⁺-/ClO₃⁻-haltigen Lösung vom Reduktionsmittel Fe beobachtet, die Anwesenheit von Fe bzw. Fe⁺⁺-Ionen verhindert demnach die Oxidation von Cu⁺ zu Cu⁺⁺. Als gesichert ist die Reduktion von Sb₂S₃ zu metallischem Sb anzusehen, unterstützt durch den oxidierenden Einfluß des Chlorates auf das Sulfid:



        (7)   Sb₂S₃ + 2 ClO₃ → 2 Sb⁺⁺⁺ + 3 SO₂ + 2 Cl⁻





        (8)   Sb⁺⁺⁺ + Fe → Sb + Fe⁺⁺⁺



Nach der vollständigen Umsetzung des Kaliumchlorates setzt sich mit der Zeit die reduzierde Wirkung des überschüssigen Fe durch, wie die sinkende Cu-Konzentration in der Lösung beweist:



        (9)   Cu⁺ + Cu⁺⁺ + Fe → 2 Cu + Fe⁺⁺⁺



Die Konzentration an Hg-Ionen in der Lösung, die zwar gering, jedoch eindeutig war, sank ebenfalls mit zunehmender Zeitdauer ab.



        (10)   2 Hg⁺⁺ + Hg₂⁺⁺ + 2 Fe → 4 Hg + 2 Fe⁺⁺⁺



Insgesamt kann gesagt werden, daß der Zusatz von metalllschem Eisen zu den in neutraler oder alkalischer wäßriger Lösung befindlichen Zündhütchen ausgesprochen positive Auswirkungen auf den Gesamtvorgang hat. Neben dem sicheren Beseitigen der Sprengwirkung, als dem Hauptziel der Behandlung, wird Quecksilber in die gut weiterbehandelbare metallische Form überführt und dem Auflösen der anderen Metalle, soweit sie edler als Fe sind, entgegengewirkt.The chemical reactions taking place in the proposed method for eliminating the explosive effect of the primers are very complex. Based on the raw materials and the proven end products, they can be formulated as follows:

Starting materials:

Water, brass CuZn3O, potassium chlorate, antimony trisulfide, mercury fulminate, iron, partly tin

End products:

Metallic mercury, amalgams, Fe₂O₃, Cu ions, Zn ions, Cl ions, Cu, Cu cemented to Fe, CuZn3O, undecomposed Fe, CuO, Sb.

Potassium chlorate goes into solution and acts as an oxidizing agent, the first attack applies to metallic Fe to form Fe (III) oxide:



(2) ClO₃⁻ + 2 Fe → Cl⁻ + Fe₂O₃



Intermediate Fe (II) ions are formed



(3) ClO₃⁻ + 3 Fe → Cl⁻ + 3 FeO



The Fe (II) ions have a reducing effect on the mercury fulminate and destroy it with the formation of metallic mercury



(4) 2 Fe⁺⁺ + Hg⁺⁺ → Hg + 2 Fe⁺⁺⁺



Analyzes showed that the ratio of Cu to Zn ions in the aqueous solutions does not correspond to the ratio of the two metals in the alloy CuZn3O, but a high excess of Cu ions occurs. It can therefore be assumed that the metallic mercury preferably forms Zn amalgam and the resulting finely divided copper is oxidized to Cu⁺ by chlorate:



(5) 6 Cu + ClO₃⁻ → 3 Cu₂O + Cl⁻





(6) 3 Cu₂O + ClO₃⁻ → 6 CuO + Cl⁻



Reaction (6) was only observed after the Cu⁺- / ClO₃⁻-containing solution had been separated from the reducing agent Fe, and the presence of Fe or Fe⁺⁺ ions thus prevented the oxidation of Cu⁺ to Cu⁺⁺. The reduction of Sb₂S₃ to metallic Sb can be regarded as certain, supported by the oxidizing influence of chlorate on the sulfide:



(7) Sb₂S₃ + 2 ClO₃ → 2 Sb⁺⁺⁺ + 3 SO₂ + 2 Cl⁻





(8) Sb⁺⁺⁺ + Fe → Sb + Fe⁺⁺⁺



After the complete conversion of the potassium chlorate, the reducing effect of the excess Fe assumes itself over time, as the decreasing Cu concentration in the solution proves:



(9) Cu⁺ + Cu⁺⁺ + Fe → 2 Cu + Fe⁺⁺⁺



The concentration of mercury ions in the solution, which was low but unambiguous, also decreased with increasing time.



(10) 2 Hg⁺⁺ + Hg₂⁺⁺ + 2 Fe → 4 Hg + 2 Fe⁺⁺⁺



Overall, it can be said that the addition of metallic iron to the primers in neutral or alkaline aqueous solution has extremely positive effects on the overall process. In addition to the safe elimination of the explosive effect, as the main goal of the treatment, mercury is converted into the metallic form, which can be further processed, and the dissolution of the other metals, as far as they are more noble than Fe, is counteracted.

The iron passing into the ionic form largely precipitates as Fe₂O₃.

These results ensure that a final wastewater treatment is promising and not very expensive.

• die absolut sichere quantitative Umwandlung dar Sprengmittel,
• die weitestgehende Anpassung an die Technologie der Delaborierung,
• universelle Verwendbarkeit,
• kein zusätzlicher Einsatz umweltbelastender Hilfsmittel und -stoffe,
• nur wenige technologische Schritte,
• einfache Handhabbarkeit und
• der Erhalt des metallischen Zustandes der Messingnäpfe.

The method according to the invention has the following advantages:

• the absolutely safe quantitative conversion of explosives,
• the greatest possible adaptation to the technology of delaborating,
• universal usability,
• no additional use of environmentally harmful aids and materials,
• just a few technological steps,
• easy handling and
• maintaining the metallic condition of the brass bowls.

The invention is explained in more detail below using an exemplary embodiment.

Example:

The primers in cartridge cases are pretreated in a water bath heated to 90 ° C for 2 h. In a subsequent thermal aftertreatment, the residual water adhering to the parts is evaporated.

The evaporation temperature is kept at 100 ° C. The prolonged exposure to water vapor at approx. 100 ° C loosens the connection between the cartridge and primer. In the event of exposure to higher temperatures (near 130 ° C) and simultaneous presence of water vapor, the conversion of mercury fullminate into pyrofulmin is initiated. The grain boundaries of the rhombic fulminate crystals are partially destroyed and the reaction areas are enlarged.

The primers pretreated in this way, still pressed into the cartridge cases, are separated from the cartridge case within 3 to 12 hours and subjected to a treatment in the following manner:
8 kg of iron in the form of the anvil parts are added to a quantity of 10 kg primer (basic primer with mercury fullminate). A weakly alkaline soap solution (pH 7.5 to 8.5; 1 kg of industrial soap to 400 l of water) is poured over this mixture until the liquid is about 5 cm above the solid. After mixing, the batch must stand until the hard-pressed primer in the primer has completely penetrated the medium and the conversion of the mercury fullminate with reaction with iron ions into an inert mercury compound or metallic mercury and the conversion of the potassium chlorate into potassium chloride has taken place.

Claims (5)

1. Process for treating percussion caps of cartridges and similar units of military products which contain mercury compounds, potassium chlorate and antimony trisulphide, characterized in that

   a) the percussion caps located in the cartridge cases are pretreated in a water bath, e.g. at temperatures of 70 to 100°C for a period of 30 min to 4 h, the temperature and time being freely selectable,

   b) the cartridge cases containing percussion caps thus pretreated are subjected to a post-treatment at a temperature between 80 and at most 142°C for 30 to 60 min to evaporate the residual water and to break up the crystalline structure of the mercury fulminate,

   c) the percussion caps pressed into the bases of the cartridge cases are mechanically separated off from the cartridge cases within 3 to 12 h after completion of the process described in b),

   d) then the percussion caps are mixed with finely divided iron or corrodible iron materials and then water or an aqueous solution containing ingredients of alkaline action is poured over the mixture, the amount of the medium being chosen so that it covers the percussion caps and the iron,

   e) the batch remains standing until the primer charge in the percussion caps is completely penetrated by the water or the aqueous solution containing ingredients of alkaline action and the potassium chlorate which has passed into solution has oxidized the iron and has been converted to potassium chloride and the iron ions have converted the mercury compounds into inert mercury compounds or metallic mercury,

   f) the resulting mercury-containing residues are reprocessed.
2. Process according to Claim 1, characterized in that the detonator cap likewise released on expelling the percussion caps is used as an iron component.
3. Process according to Claim 1 or 2, characterized in that the iron is recovered after the demercurizing process by magnetic separation and is re-used as reducing agent.
4. Process according to Claim 1b, characterized in that the conversion of the mercury fulminate into pyrofulmin is initiated at temperatures above 110°C.
5. Process according to Claim 1d, characterized in that, e.g., soap, sodium hydroxide solution or others are used as aqueous solution containing ingredients of alkaline action.