RU2051588C1 - Device for drying fruit and berries - Google Patents

Abstract

FIELD: agriculture. SUBSTANCE: device has a vertical cylindrical body. Inside the body there is a turret. The latter is a driven shaft. A framework is mounted on the shaft, and secured on the framework in tiers are gauze pallets for fruit and berries, means for delivery and withdrawal of drying agent, and energy supply means. The frame is a cone in shape, and the pallets are funnels in shape. They are secured on the framework so that they are inclined toward the shaft. The energy supply means is a microwave generator with radiators located in one of the sectors of the body over each tier of pallets. EFFECT: higher efficiency. 2 dwg

Description

 The invention relates to agriculture, in particular to devices for drying grapes, as well as fruits and berries.

 The purpose of the invention is to accelerate the drying process and uniform tier distribution of heated air for convective drying.

 In FIG. 1 shows a cross section of a drying chamber; figure 2 the principle of drying the product by exposure to microwave energy.

 The device consists of a drying chamber 1 (Fig. 1), formed by a cylindrical body 2 with covers, with an inlet nozzle 3 and an outlet nozzle 4. Inside the chamber, a carousel 7 is installed on the shaft 5 with bearings 6, on which pallets 8 are tiered. Between each tier 9 there are slots 10 for supplying and discharging a drying agent. Tiers 9 spiral onto the frame 11, made on the side of the shaft 5 in the shape of a cone. The mesh pallets 8 on each tier 9 are collectively funnel-shaped and mounted on the frame 11 with an inclination towards the shaft 5. In one of the sectors of the housing 2, microwave emitters 12 are connected over each tier 9 of the drying chamber, connected via a microwave splitter 13 with Microwave generator 14. Carousel 7 is driven by a drive 15.

 The device operates as follows.

 The hot air stream enters through the inlet nozzle 3 into the drying chamber 1 and through the slots 10 between the tiers 9 enters the mesh pallets 8. Since the slots 10 are inscribed on the side surface of the cone of the frame 11, the hot air stream does not encounter resistance to its movement and enters under each tier 9 practically at the same temperature and evenly.

 The drying agent passes through the product, partially through the gaps between the cylindrical body 2 and the pallets 8, the nozzle 4 and goes into the atmosphere or for recycling. Due to the uniform distribution of the air flow under each tray 8, a greater intensity and uniformity of the drying process is achieved. In addition, the installation in one of the sectors of the housing 2 above each tier of microwave emitters 12 during the rotation of the carousel 7, allows you to periodically increase the temperature inside the berries, which excludes caramelization during the drying process.

 In FIG. Figure 2 shows conventionally the principle of the influence of microwave energy on a berry, for example, a grape passing through six conditional provisions of the zones of a carousel dryer (A, B, C, D, E, F) during its continuous rotation.

 In zone A, microwave irradiation occurs, the direction of action of which is indicated by arrows (figure 2). In zone B, after irradiation, the temperature and, consequently, the internal partial pressure of moisture vapor in the berry increases (conditionally shown by a circle of the corresponding diameter), which contributes to intensive evaporation of not only “free” but also moisture adsorbed in the berry, in addition, on the surface of the berries microcracks occur, which also accelerates the evaporation of moisture. In zone C, the berry begins to cool gradually, the internal partial pressure gradually decreases, and when the berry passes through zones D, E, F it reaches a “normal” value, at which only normal convective drying occurs when the air flow temperature is set inside the dryer. When the berry reaches zone A, the process repeats again.

 Since thermal moisture conduction coincides with the direction of the heat flux, processing of the product with microwave energy facilitates the movement of beneficial aromatic, coloring and flavoring substances in the shell and in the surface layer of the berry into the fruit and is stored in dried products.

 Periodic exposure of microwave energy to the dried product creates favorable conditions for drying, because it allows you to increase the vapor pressure inside the berries at a lower surface temperature of the berries, thereby speeding up the drying process and exclude caramelization of the finished product.

The drying of berries and fruits, in particular grapes, is carried out in a rotary dryer at a rotational speed of 1-2 revolutions per minute. Microwave energy is irradiated over each tier with a power of 3 kW and a frequency of 2.5 GHz for 5-10 s. Convective drying is carried out in an air stream with a temperature of 70-85 ^C. To improve performance, can be used microwave generator power of 50 kW with a frequency of 915 MHz and then dividing the power.

Claims (1)

 DEVICE FOR DRYING FRUITS AND BERRIES, containing a vertically mounted cylindrical body located inside the carousel, representing a shaft with a rotary drive, a frame fixed to the shaft and mesh pallets belt-mounted on the frame to accommodate the processed material, means for supplying and removing the drying agent and means for supplying energy, characterized in that the frame has the shape of a cone, and the mesh pallets have the shape of funnels and are mounted on the frame with an inclination towards the shaft, while the means for For energy supply it is a generator of superhigh-frequency energy, and energy emitters are located in one of the sectors of the body above each tier of mesh pallets.

Images