FR2488684A1 - Processing bulk material in vibratory tunnel conveyors - resiliently and sealingly interconnected in series and individually controllable - Google Patents

Abstract

The arrangement is intended for continuous physical and/or chemical treatment of bulk material in a multi-stage process. Each processing stage is carried out on a vibratory tunnel conveyor (1) having its own oscillator drive assembly (2) with individually controllable frequency and/or amplitude. The conveyors are arranged one behind the other and are interconnected via resilient sealing sleeves (3). Each conveyor trough (1) may be upwardly closed by a heat-resistant resilient seal (5) carried by a fixed frame (4) above it and a hinged heat-insulated cover (6) which may carry radiant heaters (9) and inspection windows (10), whilst fans (20) may blow cooling air (at 14) against the bottom of the trough. Gaseous reaction products may be extracted via connections (15).

Description

 The present invention relates to a device for the continuous treatment of a bulk material in several stages of chemical and / or physical treatment.

 In order to obtain bulk materials of a determined chemical composition and physical consistency, it is frequently necessary to subject the raw materials to several successive treatments such as drying by heating or by sweeping with hot air, transformation only by heat or by mixing with other solid, liquid or gaseous substances requiring the application of heat or which can be created by heat which must then be dissipated. The treatment may require the use of toxic or explosive substances or gases or else such substances are released by the reaction.

 For the implementation of the above treatments it is known to use rotary tubular ovens in which there are significant sealing problems and whose solution is expensive, agitator mixers in which the treatment for obtaining a mixture satisfactory requires a relatively long time and is difficult to monitor, and helical oscillating conveyors arranged in cylindrical containers, which can only be produced for small quantities of material and in which the different treatment zones cannot be separated sufficiently Since there is only one drive, we can only obtain for these helical transporters a single oscillation frequency with a single amplitude which does not allow the oscillations to be adapted to the flow properties of the loose material which vary during processing.

 The object of the present invention is to allow the continuous treatment of a bulk material by means of a multi-stage device and in which it is possible to correctly separate the different treatment zones from one another while being able to adapt, optimally, the speed of transition to the momentary consistency of the material in brac.

 The above problems are solved in accordance with the invention by a treatment device which is characterized in that each treatment stage comprises a conveyor with oscillating movements driven by a clean vibrator and the transport capacity of which can be controlled and adjusted individually by varying the frequency and / or amplitude of the oscillations and in that the oscillating movement conveyors mounted one after the other in the production installation are connected to each other by elastic cheification stage sleeves and compensating for the antagonistic movements.

 Various other characteristics of the invention will also emerge from the detailed description which follows.

 Embodiments of the object of the invention are shown, by way of nonlimiting examples, in the accompanying drawings.

 Fig. 1 shows in side elevation a chain, extendable at will, of oscillating movement conveyors, each of which represents a processing stage.

 Fig. 2 shows, in section, a conveyor with oscillating movements which is intended, in particular, for the heat treatment of a bulk material.

 Each of the oscillating movement conveyors 1 which are resiliently mounted, in the usual way, on a fixed frame, is driven individually, with regard to the frequency and / or amplitude of the oscillations, by a control of oscillations 2 constituted by a magnet with reciprocating movements or by unbalance drive, in order to create the transport conditions adapted to the momentary consistency of the bulk material. The conveyors with oscillating movements, mounted one after the other, are connected by elastic sealing sleeves 3 in order to compensate for the movements of oscillations and to prevent these movements, which are different from a conveyor to the other side of the treatment chain, to be upset.

 Each of the oscillating movement conveyors 1 constitutes a stage for a particular treatment of the bulk material and it is correspondingly equipped.

A heat treatment stage is described below by way of example.

 The neck of the conveyor with oscillating movements is closed on its top by a fixed cover 6, not accompanying the oscillations, and which rests by its peripheral edge on a frame 4. The shutter of the treatment chamber relative to the the exterior and the compensation of the oscillating movements are obtained by a peripheral sealing sleeve 5 which is elastic and, where appropriate, gas-tight and heat-resistant and which, in a particular embodiment, is called "compensator with tissue". In order to be able to access the interior space, the cover 6 is advantageously connected to hinges by one of its catches so as to be able to pivot upwards. In the example shown, the cover 6 is suspended to pivot in the center 16 of a cross member extending above the oscillating conveyor and to which it is connected to pi vote by one of its ends and by means of hinges 7. A seal 19, peripheral and heat resistant , seals the interior space when the cover 6 is forcibly applied. A support plate 17 which is intended for mounting the heating elements 8, is suspended from the cover 6 by means of elements having oblong holes and slots to compensate for thermal expansions. The support plate 17 is advantageously made in the form of a reflector for the radiation of heat. It is obvious that the heating elements 8 can be energized individually or in groups, as required, to obtain heating zones 9.

 In order to be able to observe and monitor the reaction process inside the oscillating conveyor 1, sleeves 13 provided with transparent glasses 10 and inclined towards the edge, are provided in the cover 6. Since the reflections cannot be not title avoided during lighting and observation through a single glass, it is known and usual to provide two separate light paths either by using two sleeves side by side or a single single sleeve provided with two glasses A simple improvement according to the invention provides for having diametrically and directly below the observation glass 10 a separation wall colored in black in order to eliminate the reflections produced by the lighting and causing the observation.

 Thermal probes 18 may be provided in the bottom of the oscillating conveyor 1 for monitoring the temperature or for direct adjustment and control thereof.

 In order to protect the oscillating conveyor 1 against overheating and / or to be able to influence the course of the treatment process, it is possible to provide under the bottom of the conveyor 1 mouths 14 of air supply ducts from blowers 20 and opposite these mouths on the upper side of the suction ducts 15.

 Thanks to the vibrating movements imprinted on the bulk material, the frequencies and amplitudes of which can be adjusted individually for each conveyor l, it is possible not only to adapt the transport speed to the particular processing process for the bulk material but also to obtain mixing and a permanent mixture of the latter, if necessary, with additional solid, liquid or gaseous substances, with heating or cooling air or gases, for example protective gases, as well as a rapid and uniform distribution heat.

 When the chute of the oscillating movement conveyor 1 is strongly heated as a result of heating or an exothermic chemical reaction, the chute and its fixing elements, in particular its support element 1 'expand differently. In order to take account of these thermal expansions, it is advantageous to provide, at the level where the longitudinal expansion occurs, only a fixed connection at a single location and in the other areas only tight connections that can be slid.

Claims (14)

 1 - Device for the continuous treatment of a bulk material in several stages of chemical and / or physical treatment, characterized in that each treatment stage comprises a conveyor with oscillating movements (1) driven by a clean vibrator (2) and whose transport capacity can be individually controlled and adjusted by varying the frequency and / or amplitude of the oscillations and in that the oscillating movement conveyors (1) mounted one after the other in the installation of production are connected to each other by elastic sealing cuffs (3) which compensate for the opposing movements.  2 - Device according to claim 1, characterized in that fixed frames (4) connected to the oscillating conveyor (1) by means of peripheral sealing sleeves (5) elastic, heat resistant and gas tight, are arranged above one, several or all of the oscillating conveyors (1).  3 - Device according to claim 2, characterized in that covers (6) carrying heating elements (8) and insulated (6 ') by means of peripheral seals (19), heat resistant and hermetically closing, are arranged on one or more frames (4).  4 - Device according to claim 3, characterized in that the covers (6) are connected by one of their sides to hinges (7) so as to be able to pivot upwards.  3 - Device according to claim 4, characterized in that the covers (6) are suspended to pivot freely in the center (16) of sleepers which are connected by one of their ends to hinges (7) and in that the covers carry , by means of elements having oblong holes and slots to compensate for thermal expansions, plates (17) which carry the heating elements (8) and at the same time serve as reflectors.  6 - Device according to claim 5, characterized in that the heating elements (8) are supplied with electric current individually or in groups to create heating zones (9).  7 - Device according to one of claims l to 6, characterized in that the covers (6) carry oblique sleeves (13) provided with observation glasses (10).  8 - Device according to claim 7, characterized in that a partition wall (11), colored black, is mounted diametrically inside the sleeve (13) to prevent reflections.  9 - Device according to claim 7, characterized in that an air inlet pipe (12) is connected to the sleeve (13) to expel the dust settling on the observation glass (10).  10 - Device according to one of claims 1 to 9, characterized in that the sealing sleeves (3, 3) are made in the form of "fabric compensators".  11 - Device according to one of claims 1 to 10, characterized in that thermal probes (18) are arranged at the bottom of the oscillating conveyor 1 to monitor and control the reaction process or processes.  12 - Device according to one of claims 1 to 11, characterized in that the duct intake ducts (14) from cooling blowers (20) are provided below the bottom of the oscillating conveyor (1).  13 - Device according to one of claims 1 to 12, characterized in that the heating, reaction and cooling zones on the conveyor with oscillating movements (1) are arranged and controlled so that the gaseous reaction products produced especially clear near a suction duct (15) provided for this purpose.  14 - Device according to one of claims 1 to 13, characterized in that the chute of the oscillating conveyor (1) is fixed on the element (1 ') carrying the dtentrainement prpr vibrator (2) so as to be able to slide in places to take account of the different thermal expansions appearing during operation.