DE2033634B

DE2033634B - Emptying device on silos with a flat bottom

Info

Publication number: DE2033634B
Authority: DE
Inventors: Walter Küsnacht Merz (Schweiz)
Original assignee: Schweizerische Aluminium AG
Current assignee: Rio Tinto Switzerland AG

Description

2 033Ό342,033-34

mittlung des günstigsten Schüttgutkegelwinkels für Tonerde stellte sich eine Eigenförderung des fluidisierten Schüttgutes, d. h. eine Förderung des Schüttgutes bei geöffnetem Auszug ohne Zuhilfenahme eines Teiles der fluidisierenden Luft als Transportmittel ein, wenn die Steigung des Schüttgutkegels zum flachen, horizontalen Boden des Entleerungstunnels etwa 10 °/o beträgt.averaging of the most favorable bulk material cone angle for Alumina turned itself into a self-promotion of the fluidized bulk material, d. H. a conveyance of the bulk material when the pull-out is open without the aid of part of the fluidizing air as a means of transport on when the slope of the bulk material cone to the flat, horizontal floor of the emptying tunnel is about 10 ° / o.

Durch die Einbringung einer die Böschung, d. h. den Schüttkegelwinkel konstant haltenden Querschnittsverengung in den Entleerungstunnel wird ein störungsfreier Austrag gewährleistet. Die vorteilhafte Wirkung dieser Anordnung wird durch die Wahl eines eigenfördernden Schüttkegelwinkels noch dadurch verstärkt, daß die zur Förderung des Schüttgutes mit gleichbleibender, aber nicht selbst fördernder Böschung sonst notwendigen Luftmenge eingespart werden kann, was sich bezüglich der Betriebskosten des Silos aufwendungsmindernd auswirkt. Auch sind die durch die erfindungsgemäße Böschungswahl vor dem Siloaustrag bei geschlossenem Austrag auflaufenden Schüttgutmassen geringer. Hierdurch werden die zum Siloaustrag gehörenden Teile kostensparend schwächer dimensionierbar.By introducing a slope, d. H. the cross-sectional constriction keeping the angle of repose constant Trouble-free discharge is guaranteed in the emptying tunnel. The advantageous one The effect of this arrangement is further enhanced by the choice of a self-supporting cone angle reinforced that the promotion of the bulk material with constant, but not self-promoting Embankment otherwise necessary amount of air can be saved, which affects the operating costs of the silo reduces expenditure. Also, by the choice of slope according to the invention are available When the discharge is closed, the bulk material masses accumulating in the silo discharge are reduced. This will be the parts belonging to the silo discharge can be dimensioned weaker to save costs.

Eine bevorzugte Ausführungsform der Erfindung wird im folgenden an Hand der Zeichnungen näher erläutert und es stellen darA preferred embodiment of the invention is explained in more detail below with reference to the drawings explained and it represent

F i g. 1 einen Querschnitt durch den unteren Teil eines Silos, wobei der Entleerungstunnel in seiner Länge geschnitten ist,F i g. 1 shows a cross section through the lower part of a silo, with the emptying tunnel in its Length is cut,

F i g. 2 einen Querschnitt durch den Entleerungstunnel. F i g. 2 shows a cross section through the emptying tunnel.

Mit 1 sind die Auflockerungsrinnen bezeichnet, welche gleichmäßig verteilt, radial im Siloboden angeordnet sind, und die Aufgabe haben, das Gut gleichförmig von allen Bereichen des Silobodens zum Zentrum des Silobodens zu fördern. Zum Austrag verbindet ein Entleerungstunnel 3 das Zentrum des Silobodens mit dem Siloauslauf 9, wobei das Gut in den vollen Querschnitt am Anfang des Entleerungstunnels eingeleitet wird. Der Querschnitt des Entleerungstunnels kann eine beliebige Form besitzen. Auf Grund der Fluidisierung des Gutes mittels eingeblasener Luft kann die Höhe des Entleerungstunnels gering gehalten werden. Andererseits steht einer solchen Höhe des Entleerungstunnels, die ihn begehbar macht, nichts entgegen. Zur möglichst vollständigen Entleerung des Silos ist es zweckmüßigv die Begrenzungsflächen zum Abrutschen des auf ihnen lagernden Gutes möglichst stark geneigt anzuordnen. Als Baustoff für den Entleerungstunnel kommen verschiedene Materialien, wie z. B. Beton oder Stahlröhren in Betracht.With 1 the loosening channels are referred to, which are evenly distributed, arranged radially in the silo bottom and have the task of bringing the material uniformly from all areas of the silo floor to the Promote center of silo bottom. An emptying tunnel 3 connects the center of the Silo bottom with the silo outlet 9, whereby the material is introduced into the full cross-section at the beginning of the emptying tunnel. The cross section of the emptying tunnel can be of any shape. Due to the fluidization of the goods by means of blown Air, the height of the emptying tunnel can be kept low. On the other hand, there is one Nothing against the height of the emptying tunnel, which makes it accessible. For the most complete It is advisable to empty the silo from the boundary surfaces to be arranged inclined as much as possible so that the goods stored on them slide off. When Building material for the emptying tunnel come from various materials, such as B. concrete or steel pipes into consideration.

Im Mittelteil des Tunnels ist eine Querschnittsverengung 4 angebracht, die den Materialstrom reduziert,In the middle part of the tunnel there is a cross-sectional constriction 4, which reduces the flow of material,

ίο um ihn anschließend im letzten Abschnitt 5 des Entleerungstunnels dem Siloauslauf 9 gleichmäßig zuzuleiten. Der Auszug des Silogutes läßt sich besonders gut bewerkstelligen, wenn das Verhältnis der offenen Höhe an der Verengung zur Länge des Entleerungstunnels zwischen Verengung und Siloauslauf (Abschnitt 5) dem Tangens des Schüttkegelwinkels des Gutes im aufgelockerten (fluidisierten) Zustand entspricht. Das fluidisierte Gut bildet so, wie bereits erwähnt, einen bezüglich des Austrages optimalen freier.ίο around him then in the last section 5 of the emptying tunnel to feed the silo outlet 9 evenly. The extraction of the silo can be special do well when the ratio of the open height at the constriction to the length of the emptying tunnel between the constriction and the silo outlet (section 5) the tangent of the angle of the pouring cone of the Corresponds to good in the loosened (fluidized) state. As already mentioned, the fluidized material forms one that is optimal in terms of discharge.

Schüttkegelwinkel, der viel kleia^r ist als der Schüttkegelwinkel des nicht fluidisierten Gutes. Ist nun die offene Höhe der Verengung im Verhältnis zur Länge des Abschnittes kleiner, als daß sich der freie Schüttkegel im fluidisierten Zustand ausbilden könnte, soAngle of repose, which is much smaller than the angle of repose of the non-fluidized good. Now is the open height of the constriction in relation to its length of the section smaller than that the free cone of material could form in the fluidized state, so

wird die Auszugsleistung geringer. Im anderen Fall einer zu großen offenen Höhe können im Abschnitt 5 Materialstauungen entstehen. Wird die Querschnittsverengung so ausgebildet, daß sich im Abschnitt 5 des Entleerungstunnels 3 der freie Schüttkegelwinkelthe pull-out capacity will be lower. In the other case of too great an open height, in section 5 Material jams arise. If the cross-sectional constriction is designed so that in section 5 of the emptying tunnel 3 is the free angle of the cone of repose

des fluidisierten Gutes ausbilden kann, so kann die vom Entleerungstunnel 3 überdeckte Auflockerungsrinne 1 mit einer geringeren Luftmenge beaufschlagt werden.of the fluidized material can form, the loosening channel 1 covered by the emptying tunnel 3 can be acted upon with a smaller amount of air will.

Mittels einer Regeleinrichtung 8 läßt sich die För-By means of a control device 8, the conveying

dergutmenge am Siloauslauf 9 dosiert ausziehen. Wird der Siloabsperrschieber 10 geschlossen, so wird die Förderung, ausgehend vom im Abschnitt 4 aufgelaufenen Schüttkegel, unterbrochen. Die Auflockerungsluft entspannt sich zu jedem Zeitpunkt dadurch,Pull out the amount of material at the silo outlet 9 in a metered manner. If the silo gate valve 10 is closed, then the conveyance, starting from the cone accumulated in section 4, is interrupted. The loosening air relaxes at any point in time

daß sie nach Durchtritt durch das Material, durch ein Druckausgleichsrohr 7 entweichen kann, das in den Abschnitt 5 einmündet. Ein Verstopfen des Druckausgleichsrohres 7 mit Silogut kann durch in ihm angebrachte Auflockerungsrinnen 6 verhindert werden, die während der Entleerung ständig mit Luft beaufschlagbar sind.that they can escape after passing through the material through a pressure equalization tube 7, which is in the Section 5 opens. A clogging of the pressure equalization pipe 7 with silage material can be attached to it Loosening channels 6 are prevented, which can be constantly acted upon with air during emptying are.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

Claim:

Emptying device for silos with radially arranged in the floor, pressurized with air Loosening channels, of which at least one is used as a conveyor trough to promote the dusty or fine-grained goods to a side silo outlet and with one of a central one Bottom zone as far as the silo outlet and an emptying tunnel with a narrowed cross-section is covered, in which a ίη denotes the free The pressure equalization pipe protruding from the silo opens out between the cross-sectional constriction and the silo outlet, characterized in that the emptying tunnel having a flat, horizontal bottom (3) the cross-sectional constriction in its middle part '(4) at such a distance from Silo outlet (9) has that the ratio of the difference between the open height at the Cross-sectional constriction (4) and the height of the cross-section of the silopus run (9) to this distance corresponds approximately to the tangent of the angle of the pouring cone of the loosened material.

The invention relates to an emptying device for silos. An emptying device for silos with loosening channels arranged radially in the ground and exposed to air, of which at least one As a conveyor trough for conveying the powdery or fine-grained material to a side silo outlet and with a cross section that extends from a central floor zone to the silo outlet provided emptying tunnel is covered, in which a protruding into the free silo space Pressure equalization pipe discharges between the cross-sectional constriction and the silo outlet is known.

Loosening channels placed in the silo floors and pressurized with air, those on the inside of the silo facing sides with porous, air-permeable fabric or with air-permeable ceramic or metal plates are covered, serve to extract the dusty or fine-grained silo contents, in which the air, which is fed to the loosening troughs via connecting pipes, removes the silo contrary to its other tendency, by its own weight and by shock waves that occur when refilling of the silo as well as when material bridges collapse from bulk material and are evenly distributed in the Continuing bulk solids, compacting to the point of non-flow, fluidizing, d. H. makes it flowable. For silos with centrally arranged in the floor discharge device, z. B. in silos with conical bottom, there are none special arrangement regulations relating to the laying of the channels. In contrast, the bulk goods tend in the case of flat-bottomed silos with a lateral extension, uneven slopes or material walls in the silo form, which by their collapse, in addition to bulk material compaction, force the silo walls to be reinforced. This is countered by the fact that the silo contents from the center of the silo bottom over a radial The emptying tunnel was removed to pull out, the one for fluidization and transport of the bulk material in the emptying tunnel a also radial loosening channel is covered, whereby the arrangement of the rest, not having a F.dleerungstun, nel covered loosening channels in the same way for fluidization and The bulk material is to be conveyed in the direction of the center of the silo floor. The bulk material occurs under the formation of the bulk material own, through the formation of the tunnel and the type of

ίο fluidization influenced from the discharge end to Entry end of the emptying tunnel ascending embankment into the Entjeeningstunnel, in order to go out from the embankment, supported by the fluidization, to flow to the discharge. This type of silo discharge has the disadvantage that the bulk material does not flow evenly.

In the case of a silo with a bottom sloping towards the laterally arranged silo discharge, it is a Emptying tunnel known with a narrowing of the cross-section. This cross-sectional constriction exerts on the by refilling the silo or by collapse of material bridges into the emptying tunnel continuing pressure surges with the help of a subsequent to the cross-sectional constriction Chamber exerts a dribbling effect, which prevents bulk solidification in the emptying tunnel will. A means for the formation of a constant, the uniform silo pull-out guarantee This means that there is no angle of repose.

The object on which the invention is based is therefore to avoid interference to reduce the conveying path between the constriction and the silo outlet and one before the constriction Compensation zone for the shock waves resulting from refilling the silo or material bridge collapse to accomplish.

This object is achieved in the emptying device described above in that the a flat, horizontal floor having an emptying tunnel the cross-sectional constriction in his Center part at such a distance from the silo outlet that the ratio of the difference between dev open height at the cross-sectional constriction and the height of the cross-section of the silo outlet to this Distance about dt-τη tangent of the Schüttkegehvinkel of the loosened good.

To achieve this goal, it was assumed that that the reason for the uneven discharge of the silo in bulk material stowage in the emptying tunnel, triggered by shock waves caused by refilling the silo or material bridges collapsing and change the embankment of the bulk material in the emptying tunnel contrary to funding, is to be looked for, whereby their The effect of inhibiting the conveyance can no longer be eliminated by fluidization. These shock waves are initially balanced in the part of the emptying tunnel located in front of the narrowing of the cross-section. The removal of the change in the embankment that is contrary to conveyance is implemented in the case of the one constructed according to the invention Silo containers are also achieved with an emptying tunnel with a flat horizontal bottom through a narrowing of the cross-section to the extent that than the one from the silo discharge to the point where it is

6g bringing a bulk material cone in the emptying tunnel through mechanical effects of the aforementioned Guaranteed kind of unchangeable slope in the direction of the transverse stiffness change. At the