DD236006A1 - DEVICE FOR ROASTING GEKOERNTEN GUETERN - Google Patents

Abstract

Device for roasting gekoernten goods such as coffee beans in the fluidized state. The aim is to achieve an increased quality of the product with a reduced effort for the production of the device by an equal treatment of all particles with short process times. The device should have a small specific space requirement and a low construction height. In the device according to the invention a rotatable Anstroemboden is arranged above a gas distribution chamber and below a fluidized bed chamber. The rapid and complete emptying of the fluidized bed chamber is achieved due to the tendency of the Anstroembodens that during the Roest-, cooling or drying process assumes a horizontal position, achieved by a laterally arranged, cramped executed discharge flap.

Description

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Field of application of the invention

The invention relates to a device for roasting, cooling or drying of granular goods such as coffee beans or cereals. It can preferably be used in the food industry, in particular in coffee roasting.

Characteristic of the known technical solutions

There are already known various devices for roasting, cooling or drying of granular goods, in which the roasting, cooling or drying takes place by fluidization. These devices have the advantage of uniform, gentle roasting at low temperatures and short processing times over devices which are roasted, cooled or dried in drums, balls or trays with or without moving internals such as blades.

The applicability of devices, and those by roasting by fluidization, d. H. Hovering the granular particles in an upward gas flow over an inflow bed has been known for 60 years. These devices are usually referred to as fluidized bed apparatuses. These devices work to ensure equal dwell lines for all particles in batch batch mode by alternately running the filling, roasting (cooling, drying) and deflating cycles.

Since the uniformity of the quality of the finished product depends especially on the abrupt termination of the fluidization process and the complete emptying of the fluidized bed chamber, especially in the treatment of roasted coffee, the combination of good heat and mass transfer conditions during fluidization and the

rapid emptying of the fluidized bed chamber of great importance. ·

For emptying the fluidized bed chamber, the roasting material is carried away in the DR-472391 after the roasting process with the Röstgasstrom upwards, to the roast gas stream is amplified. The disadvantage here is that a significant increase in the Röstgasstromes is necessary for a sudden emptying of the roasting chamber and the risk of remaining residual particles in the roasting chamber is large.

In DD-WP 137473, the emptying of a fluidized bed chamber takes place only laterally through a closure with the support of the gas flow. Wherein the closure is arranged above a firmly clamped, horizontal inflow base. In this case, the gas flow is not amplified for emptying. A disadvantage of this device is that there is a risk of remaining of residual beans in the fluidized bed chamber.

In the DD-WP 160209, the emptying of the roasting chamber is carried out by a separate, inner part of the inflow base, which is designed as a flap. A disadvantage of this device is the very large height with arranged below cooling chamber.

In DE-OS 3116723 the emptying of the roasting chamber takes place without the aid of the gas flow, which is guided past it during the emptying of the roasting chamber, solely by the inclination of the inflow bottom. Complete emptying is only possible with large soil slopes and associated inhomogeneous fluidization.

Object of the invention

The aim of the invention is a device for roasting, cooling or drying of granular goods, in particular of coffee beans, with the reduced effort for the production of the device, in particular the assembly, an improved quality and increased yield of the treated goods is achieved.

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Explanation of the essence of the invention

The invention has for its object to develop a device for roasting, cooling and drying of granular goods, in particular of coffee beans, with the short process times by good heat and mass transfer conditions a gentle and uniform treatment of the goods. The device is intended in particular to enable a rapid termination of the rust, cooling or drying process with immediate and complete emptying.

The dimensions of the device, in particular the height, should be low. The operating regime of the device should be easy to automate. The device should contain only a small number of moving components.

According to the invention the object is achieved in that the device is divided by a distributor plate in a fluid bed chamber located above the inflow base and a gas distribution chamber located below the inflow base. In the fluidized bed chamber opens a gas outlet nozzle and a Rohproduktintrittsstutzen. In the gas distribution chamber opens a gas inlet nozzle.

According to the invention, the distributor plate is a gas-permeable, perforated, rectangular, flat plate which is rotatable about a horizontal axis.

The rotatability of the inflow floor is limited. One limit is its horizontal position, the other limit its position inclined by the angle to the horizontal. Where the angle α is greater than 0 ° and at most 45 °.

The fluidized bed chamber has a rectangular horizontal, preferably upwardly extended cross-section.

According to the invention have within a pivot space, which is bounded both by the plane of the horizontal position of the inflow floor and by the plane of the inclined by the angle · α to the horizontal inclined position of the inflow, two curved outer walls of the device, which are arranged parallel to the axis of rotation of the inflow , A constant distance from the axis of rotation of the inflow, wherein a gap formed between the curved outer walls on the one hand and two parallel to the axis of rotation of the inflow bottom outer edges of the inflow, on the other hand, is not greater than the grain diameter of the roasted product.

The pivot space is divided into an upper and a lower space segment.

Furthermore, part of the invention that the curved outer wall, which is arranged in the lower space segment, is designed to be movable as an emptying flap. A finished product outlet nozzle, which is bounded at its upper end by the emptying flap, has an angle of inclination β to the horizontal of at least 15 °.

According to the invention, the device functions so that a gas flow through the gas inlet nozzle enters the gas distribution chamber, distributed in the gas distribution chamber, the inflow bottom flows from bottom to top and enters the fluidized bed chamber, in the fluidized bed chamber with the product to be roasted, to be cooled or to be dried forms a fluidized bed and exits through the gas outlet. The crude product enters the fluidized bed chamber via the crude product inlet connection in a predetermined amount in batches and is then fluidized by the gas flow on the distributor plate in the fluidized bed chamber. In this case, the distributor plate preferably assumes a horizontal position.

When the rusting, cooling or drying process has ended, the position of the inflow bottom is changed by inclining at an angle to the horizontal, after which the emptying flap, which is closed during the grate, cooling or drying process, opens and the finished product passes by gravity with the aid of the gas flow from the fluidized bed chamber through the opened discharge flap and the finished product discharge nozzle. After the emptying process, it is refilled with crude product.

embodiment

The device according to the invention will be explained in more detail with the fluidized bed roasting apparatus shown in FIG. 1 for roasting coffee beans.

The raw coffee enters during the filling of the fluidized bed roasting apparatus through a crude product inlet nozzle 3 in a fluidized bed chamber 2 a. The coffee to be roasted is fluidized in the fluidized-bed chamber 2 above an inflow base 4 by a gas flow.

Due to the intense heat transfer at the bean surface between the hot gas stream and the fluidized coffee beans is an intense, short roasting process. The termination of the roasting process is carried out by the emptying process.

The emptying process is initiated by turning the inflow base 4, which occupies a horizontal position during the roasting process, in a tilted by the angle α of 30 ° to the horizontal position. Thereafter, the closed during the roasting process emptying flap 5 and the roasted hot coffee beans are entrained with the gas stream and fed through the emptying flap 5 and the production product outlet nozzle 6 of the cooling.

The production product outlet nozzle 6 has a slope β to the horizontal of 30 °. After the fluidized bed chamber 2 is emptied, closes the emptying flap 5 and then the inflow base 4 rotates back to the horizontal position.

The gap between the curved outer wall 9 and the outer edge of the inflow base 4 has a constant width of s = 2mm regardless of the inclination of the inflow base 4, so that during the roasting process and the emptying process no coffee beans can get into the gas distribution chamber.

Claims (3)

Invention claim: 1. Device for roasting granular goods, designed as an apparatus with rectangular horizontal cross-section, which is divided by a distributor plate located in a above the Abströmbodens Wirbelschichtkämmer and located below the inflow gas distribution chamber and the distributor plate is a gas-permeable, perforated, rectangular, flat plate , characterized in that the distributor plate (4) is rotatable about a horizontal axis, the rotatability of the inflow base (4) at least one horizontal position and inclined by the angle α to the horizontal inclined position of the inflow base (4), within a space, the is delimited both by the plane of the horizontal position of the inflow base (4) and by the plane of the angle α inclined to the horizontal inclined position of the inflow base (4), two curved outer walls (9) parallel to the axis of rotation of the inflow base (4) are arranged at a constant distance to the axis of rotation de s inflow bottom (4) are executed and of which the lower curved outer wall (9) is designed as a movable emptying flap (5), a gap of width s between the curved outer walls (9) on the one hand and the axis of rotation of the inflow base (4) in parallel extending outer edges of the inflow base (4) on the other hand remains and the discharge flap (5) closes a production product outlet nozzle (6) with an inclination at an angle β to the horizontal. 2. Device according to point!, Characterized in that the axis of rotation of the inflow base (4) is arranged centrally in the plane of the inflow base (4). 3. Device according to item 1 and 2, characterized in that the gap width s is not greater than the grain size of the roasted product. -