FR2687592A1 - Method and device for stabilising, in a vitreous mass, particles which are capable of liberating pollutant agents and application to the stabilisation of fly ash - Google Patents

Method and device for stabilising, in a vitreous mass, particles which are capable of liberating pollutant agents and application to the stabilisation of fly ash Download PDF

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Publication number
FR2687592A1
FR2687592A1 FR9202242A FR9202242A FR2687592A1 FR 2687592 A1 FR2687592 A1 FR 2687592A1 FR 9202242 A FR9202242 A FR 9202242A FR 9202242 A FR9202242 A FR 9202242A FR 2687592 A1 FR2687592 A1 FR 2687592A1
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France
Prior art keywords
bath
polluting particles
coated
particles
coating material
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
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FR9202242A
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French (fr)
Inventor
Vanderpol Jean-Pierre
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VANDERPOL JEAN PIERRE
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VANDERPOL JEAN PIERRE
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Application filed by VANDERPOL JEAN PIERRE filed Critical VANDERPOL JEAN PIERRE
Priority to FR9202242A priority Critical patent/FR2687592A1/en
Publication of FR2687592A1 publication Critical patent/FR2687592A1/en
Pending legal-status Critical Current

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Classifications

    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C1/00Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
    • C03C1/02Pretreated ingredients
    • C03C1/026Pelletisation or prereacting of powdered raw materials
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2/00Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
    • B01J2/12Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic in rotating drums
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B1/00Preparing the batches
    • C03B1/02Compacting the glass batches, e.g. pelletising
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B3/00Charging the melting furnaces

Abstract

The invention relates to the stabilisation of pollutant particles in a vitreous mass. The pollutant particles are coated (2-6) by means of a coating material and the pollutant particles are introduced (7, 8) directly into the core of the bath (9) of molten vitreous material, the said coating material having a melting point lower than the temperature of the bath and being selected so as to constitute a temporary thermal barrier which is sufficient to prevent the pollutant particles from decomposing during their passage from the surface of the bath to the core of the bath and the vitreous material is allowed to cool. The invention applies in particular to the stabilisation of fly ash.

Description

L'invention concerne un procédé et un dispositif pour stabiliser dans une masse vitreuse, sans pollution de l'environnement, des particules susceptibles de libérer des agents polluants. The invention relates to a method and a device for stabilizing in a glassy mass, without environmental pollution, particles capable of releasing pollutants.

Elle s'applique en particulier à la stabilisation des cendres volantes. It applies in particular to the stabilization of fly ash.

On a proposé de stabiliser les cendres volantes, c'est-àdire d'empêcher qu'elles puissent libérer des agents polluants dans l'environnement, en les agglomérant en un bloc durci au moyen d'un liant hydraulique, mais ce bloc peut à la longue devenir friable et libérer les polluants. It has been proposed to stabilize fly ash, that is to say to prevent it from releasing pollutants into the environment, by agglomerating it into a hardened block by means of a hydraulic binder, but this block can the long become crumbly and release pollutants.

On a aussi proposé de piéger les cendres volantes dans une masse vitreuse mais les techniques proposées pour introduire les cendres volantes dans le magma vitreux en fusion provoquent à la surface du bain une décomposition des cendres qui libèrent dans l'atmosphère les agents polluants, notamment les métaux lourds qu'elles contiennent. It has also been proposed to trap the fly ash in a glassy mass but the techniques proposed for introducing the fly ash into the molten glassy magma cause on the surface of the bath a decomposition of the ashes which release into the atmosphere pollutants, in particular the heavy metals they contain.

La présente invention vise à stabiliser dans une masse vitreuse des particules polluantes, sans que l'incorporation de ces particules libère des agents polluants. The present invention aims to stabilize polluting particles in a glassy mass, without the incorporation of these particles releasing polluting agents.

On y parvient, selon l'invention, en enrobant les particules polluantes au moyen d'une matière d'enrobage et en introduisant les particules polluantes enrobées directement au coeur du bain de matière vitreuse en fusion, la matière d'enrobage ayant un point de fusion inférieur à la température du bain et étant choisie de façon à constituer un écran thermique provisoire suffisant pour empêcher les particules polluantes de se décomposer pendant leur traversée depuis la surface du bain jusqu'au coeur du bain, et on recueille la matière vitreuse ayant reçu les particules polluantes et on la laisse refroidir. According to the invention, this is achieved by coating the polluting particles by means of a coating material and by introducing the polluting particles coated directly at the heart of the bath of molten vitreous material, the coating material having a point of melting below the temperature of the bath and being chosen so as to constitute a temporary heat shield sufficient to prevent the polluting particles from decomposing during their passage from the surface of the bath to the heart of the bath, and the glassy material having received is collected polluting particles and allowed to cool.

Dans des modes de mise en oeuvre de ce procédé, on utilise de plus, selon l'invention, une ou plusieurs des caractéristiques suivantes
- on enrobe les particules polluantes de façon à obtenir des granules ou des pastilles dans un tube en matériau réfractaire qui débouche au coeur du bain. Dans le cas des cendres volantes, notamment, la poussée est rendue possible par le fait de l'enrobage qui permet d'agglomérer les cendres en particules plus grosses ayant une résistance mécanique suffisante pour pouvoir être poussées.
In embodiments of this method, one or more of the following characteristics are also used according to the invention
- The polluting particles are coated so as to obtain granules or pellets in a tube of refractory material which opens out into the heart of the bath. In the case of fly ash, in particular, the thrust is made possible by the fact of the coating which makes it possible to agglomerate the ash into larger particles having sufficient mechanical strength to be able to be pushed.

- on utilise comme matière d'enrobage une matière ayant un point de fusion compris entre 800 et 1 000 C, de préférence entre 850 et 900"C,
- on utilise un silicate comme matière d'enrobage,
- on utilise un silicate de sodium comme matière d'enrobage,
- on utilise un silicate de calcium comme matière d'enrobage,
- on utilise 5 à 25 % en poids de silicate par rapport au poids des particules à enrober,
- on utilise une matière d'enrobage à l'état liquide que l'on projette sur les particules polluantes pour en faire des pastilles, ensuite dans une zone suivante les pastilles sont chauffées de façon à fixer l'enrobage,
- on règle la température du bain de réception des pastilles à une valeur légèrement supérieure à 1 200"C,
- on utilise des mâchefers, du verre ou autres refus vitrifiables comme matière vitreuse,
La figure unique du dessin joint est un schéma d'un exemple de dispositif pour la mise en oeuvre du procédé, étant entendu que cet exemple n'est pas limitatif.
a material having a melting point of between 800 and 1000 ° C., preferably between 850 and 900 ° C., is used as coating material,
- a silicate is used as a coating material,
- a sodium silicate is used as a coating material,
- a calcium silicate is used as a coating material,
- 5 to 25% by weight of silicate is used relative to the weight of the particles to be coated,
- a coating material in the liquid state is used which is sprayed onto the polluting particles to make pellets, then in a next zone the pellets are heated so as to fix the coating,
- the temperature of the tablet receiving bath is adjusted to a value slightly greater than 1,200 "C,
- clinkers, glass or other vitrifiable refusals are used as the vitreous material,
The single figure of the accompanying drawing is a diagram of an example of a device for implementing the method, it being understood that this example is not limiting.

Le dispositif comprend un poste A de préparation des cendres volantes enrobées, un poste B d'incorporation de ces cendres dans un magma vitreux et un poste C de conditionnement. The device comprises a station A for preparing the coated fly ash, a station B for incorporating these ashes into a vitreous magma and a station C for conditioning.

On décrira ci-après un exemple de préparation de l'enrobage. An example of preparation of the coating will be described below.

Les cendres volantes provenant du réservoir 1 sont envoyées dans un conduit vertical ou incliné 2 tout en étant soumises à des jets d'une solution de silicate de sodium provenant de buses 3 réparties sur le parcours des cendres volantes. Les cendres ainsi mouillées sont reçues et conditionnées en pastilles sur un tapis transporteur 4 qui traverse un tunnel chauffant 5 avant de déverser les pastilles de cendres enrobées dans un récipient 6 ou dans une trémie. The fly ash coming from the tank 1 is sent in a vertical or inclined pipe 2 while being subjected to jets of a sodium silicate solution coming from nozzles 3 distributed over the route of the fly ash. The ashes thus wetted are received and packaged in pellets on a conveyor belt 4 which passes through a heating tunnel 5 before discharging the coated ash pellets into a container 6 or into a hopper.

En variante, L'enrobage se fait par une technique au tonneau, comme dans les techniques d'enrobage utilisées dans l'industrie pharmaceutique. As a variant, the coating is done by a barrel technique, as in the coating techniques used in the pharmaceutical industry.

Au poste B, les pastilles reprises du récipient 6 ou de la trémie sont envoyées par un tube d'entrée 7 dans un tube principal 8 en acier qui aboutit au coeur d'une cuve 9, un poussoir 10 permettant, si nécessaire, de pousser les pastilles dans le tube principal en direction de la cuve. At station B, the pellets taken from the container 6 or from the hopper are sent by an inlet tube 7 into a main steel tube 8 which ends at the heart of a tank 9, a pusher 10 allowing, if necessary, to push the pellets in the main tube towards the tank.

La cuve 9 contient un bain de matière vitreuse provenant d'une source quelconque appropriée. The tank 9 contains a bath of vitreous material from any suitable source.

Ces matières vitreuses sont par exemple des crasses d'acierie ou de préférence des mâchefers fondus ou pâteux provenant en continu d'une installation de combustion, en particulier une installation d'incinération de déchets et, si nécessaire, des moyens de chauffage 12 sont prévus pour maintenir la température du bain à 1 200-1 300"C.  These vitreous materials are, for example, steelworks dross or preferably molten or pasty bottom ash originating continuously from a combustion installation, in particular a waste incineration installation and, if necessary, heating means 12 are provided. to maintain the bath temperature at 1,200-1,300 "C.

Les cendres volantes agglomérées introduites au coeur de la masse vitrifiée en fusion deviennent pâteuses puis liquides et/ou gazeuses, ce qui permet leur diffusion dans l'ensemble de la masse vitreuse en fusion. The agglomerated fly ash introduced into the core of the molten vitrified mass becomes pasty then liquid and / or gaseous, which allows their diffusion throughout the molten vitreous mass.

L'introduction des cendres volantes dans le bain provoque une augmentation du volume du bain et le magma en excès est évacué par débordement au poste de conditionnement C où elle est reçue dans un récipient 11, par exemple une lingotière ou une auge contenant de l'eau de façon à former par éclatement des billes. The introduction of fly ash into the bath causes an increase in the volume of the bath and the excess magma is evacuated by overflow to the conditioning station C where it is received in a container 11, for example an ingot mold or a trough containing water so as to form bursting balls.

Les lingots ou les billes sont par exemple mis à la décharge ou utilisées comme corps de remplissage.  The ingots or balls are, for example, discharged or used as a filling body.

Bien que l'invention s'applique en particulier à la stabilisation des particules de cendres volantes, elle n'est pas limitée à cette application et elle est applicable à d'autres particules polluantes, comme par exemple des particules de graphite.  Although the invention applies in particular to the stabilization of fly ash particles, it is not limited to this application and it is applicable to other polluting particles, such as for example graphite particles.

Claims (16)

REVENDICATIONS 1. Procédé pour stabiliser des particules polluantes dans une masse vitreuse, dans lequel on enrobe les particules polluantes au moyen d'une matière d'enrobage et on introduit les particules polluantes enrobées directement au coeur d'un bain de matière vitreuse en fusion, ladite matière d'enrobage ayant un point de fusion inférieur à la température du bain et étant choisie de façon à constituer un écran thermique provisoire suffisant pour empêcher les particules polluantes de se décomposer pendant leur traversée depuis la surface du bain jusqu'au coeur du bain, on recueille la matière vitreuse ayant reçu les particules polluantes et on la laisse refroidir.1. A method for stabilizing polluting particles in a vitreous mass, in which the polluting particles are coated with a coating material and the polluting particles coated are introduced directly into the core of a bath of molten vitreous material, said coating material having a melting point below the temperature of the bath and being chosen so as to constitute a temporary heat shield sufficient to prevent the polluting particles from decomposing during their passage from the surface of the bath to the heart of the bath, the vitreous material having received the polluting particles is collected and allowed to cool. 2 Procédé selon la revendication 1, caractérisé en ce qu'on enrobe les particules polluantes de façon à obtenir des granules ou des pastilles de particules polluantes enrobées et on pousse ces granules ou ces pastilles dans un tube en matériau réfractaire qui débouche au coeur du bain.2 Method according to claim 1, characterized in that the polluting particles are coated so as to obtain granules or pellets of coated polluting particles and these granules or these pellets are pushed into a tube of refractory material which opens out at the heart of the bath . 3. Procédé selon l'une des revendications 1 et 2, caractérisé en ce qu'on utilise comme matière d'enrobage une matière ayant un point de fusion compris entre 800 et 1 000"C, de préférence entre 850 et 900"C. 3. Method according to one of claims 1 and 2, characterized in that as a coating material is used a material having a melting point between 800 and 1000 "C, preferably between 850 and 900" C. 4. Procédé selon l'une des revendications 1 à 3, caractérisé en ce qu'on utilise un silicate comme matière d'enrobage.4. Method according to one of claims 1 to 3, characterized in that a silicate is used as coating material. 5 Procédé selon la revendication 4, caractérisé en ce qu'on utilise un silicate de sodium comme matière d'enrobage.5 Method according to claim 4, characterized in that a sodium silicate is used as coating material. 6. Procédé selon la revendication 4, caractérisé en ce qu'on utilise un silicate de calcium comme matière d'enrobage.6. Method according to claim 4, characterized in that a calcium silicate is used as coating material. poids des particules polluantes. weight of polluting particles. 7 Procédé selon l'une des revendications 3 à 6, caractérisé en ce qu'on utilise 5 à 25 % en poids de silicate par rapport au7 Method according to one of claims 3 to 6, characterized in that 5 to 25% by weight of silicate is used relative to the 8. Procédé selon l'une des revendications 1 à 7, caractérisé en ce qu'on utilise une matière d'enrobage à l'état liquide que l'on projette sur un courant de particules polluantes en amont d'une zone où ce courant est chauffé, de façon à réaliser l'enrobage. 8. Method according to one of claims 1 to 7, characterized in that a coating material in the liquid state is used which is projected onto a stream of polluting particles upstream of an area where this stream is heated, so as to achieve the coating. 9 Procédé selon l'une des revendications 1 à 8, caractérisé en ce qu'on règle la température du bain à une valeur légèrement supérieure à 1 200C C.9 Method according to one of claims 1 to 8, characterized in that the bath temperature is adjusted to a value slightly greater than 1,200C C. 10. Procédé selon l'une des revendications 1 à 9, caractérisé en ce qu'on utilise des mâchefers ou autres refus vitrifiables comme matière vitreuse.10. Method according to one of claims 1 to 9, characterized in that clinkers or other vitrifiable refusals are used as the vitreous material. 11. Procédé selon l'une des revendications 1 à 10, caractérisé en ce qu'on recueille par débordement l'augmentation de volume du bain qui résulte de l'introduction des particules polluantes enrobées dans le bain.11. Method according to one of Claims 1 to 10, characterized in that the increase in volume of the bath which results from the introduction of the polluting particles coated in the bath is collected by overflow. 12. Procédé selon l'une des revendications 1 à 11, caractérisé en ce qu'on alimente en continu le bain avec la matière vitreuse.12. Method according to one of claims 1 to 11, characterized in that the bath is continuously fed with the vitreous material. 13. Procédé selon l'une des revendications 1 à 12, caractérisé en ce qu'on utilise le bain ayant reçu les particules polluantes enrobées pour constituer des lingots ou des billettes.13. Method according to one of claims 1 to 12, characterized in that the bath having received the coated polluting particles is used to form ingots or billets. 14. Dispositif pour la mise en oeuvre d'un procédé selon l'une des revendications 1 à 13, qui comprend un poste (A) d'enrobage des particules polluantes, un poste (B) d'introduction des particules polluantes enrobées dans le bain et un poste (C) de conditionnement du bain ayant reçu les particules polluantes enrobées.14. Device for implementing a method according to one of claims 1 to 13, which comprises a station (A) for coating the polluting particles, a station (B) for introducing the polluting particles coated in the bath and a bath conditioning station (C) having received the coated polluting particles. 15. Dispositif selon la revendication 14, caractérisé en ce que le poste (B) d'introduction des particules polluantes enrobées dans le bain comprend un tube (8) qui plonge dans le bain pour introduire les particules polluantes enrobées et, éventuellement, un poussoir (10) qui pousse dans le tube les particules polluantes enrobées en direction du bain.15. Device according to claim 14, characterized in that the station (B) for introducing the polluting particles coated in the bath comprises a tube (8) which plunges into the bath to introduce the polluting particles coated and, optionally, a pusher (10) which pushes the coated polluting particles into the tube towards the bath. 16. Application d'un procédé selon l'une des revendications 1 à 13, et/ou d'un dispositif selon la revendication 14 ou 15 à la stabilisation des cendres volantes. 16. Application of a method according to one of claims 1 to 13, and / or of a device according to claim 14 or 15 for the stabilization of fly ash.
FR9202242A 1992-02-26 1992-02-26 Method and device for stabilising, in a vitreous mass, particles which are capable of liberating pollutant agents and application to the stabilisation of fly ash Pending FR2687592A1 (en)

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FR9202242A FR2687592A1 (en) 1992-02-26 1992-02-26 Method and device for stabilising, in a vitreous mass, particles which are capable of liberating pollutant agents and application to the stabilisation of fly ash

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FR9202242A FR2687592A1 (en) 1992-02-26 1992-02-26 Method and device for stabilising, in a vitreous mass, particles which are capable of liberating pollutant agents and application to the stabilisation of fly ash

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020106416A1 (en) * 2018-11-20 2020-05-28 Owens-Brockway Glass Container Inc. Batch inlet and cleaning device for glass melter

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1761229A (en) * 1926-10-25 1930-06-03 Libbey Owens Glass Co Batch-feeding mechanism
US3503790A (en) * 1965-12-27 1970-03-31 Saint Gobain Method of making silica bonded to sodium metasilicate
US3955956A (en) * 1975-08-06 1976-05-11 Midland Glass Company, Inc. Process for producing glass articles
EP0034934A2 (en) * 1980-02-21 1981-09-02 Olin Corporation A process for the production of layered glass batch pellets, pellets produced by such process and apparatus for producing such pellets

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1761229A (en) * 1926-10-25 1930-06-03 Libbey Owens Glass Co Batch-feeding mechanism
US3503790A (en) * 1965-12-27 1970-03-31 Saint Gobain Method of making silica bonded to sodium metasilicate
US3955956A (en) * 1975-08-06 1976-05-11 Midland Glass Company, Inc. Process for producing glass articles
EP0034934A2 (en) * 1980-02-21 1981-09-02 Olin Corporation A process for the production of layered glass batch pellets, pellets produced by such process and apparatus for producing such pellets

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020106416A1 (en) * 2018-11-20 2020-05-28 Owens-Brockway Glass Container Inc. Batch inlet and cleaning device for glass melter
CN113015705A (en) * 2018-11-20 2021-06-22 欧文斯-布洛克威玻璃容器有限公司 Batch inlet and cleaning device for glass melter
US11084749B2 (en) 2018-11-20 2021-08-10 Owens-Brockway Glass Container Inc. Batch inlet and cleaning device for glass melter

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