RU2040882C1 - Method and device for drying flax stock - Google Patents

Abstract

FIELD: agriculture. SUBSTANCE: method and device are intended for use at primary flax-processing stations. Moisture contained in wood is evaporated from the entire volume simultaneously by electromagnetic irradiation, flows through pores under the bark and is removed by fan 10. As a result, wood turns hard and bark loses its contact with wood. The device comprises chamber 11 with SHF-radiation generator 2, conveyor 3 and fan 10 and features a high speed. EFFECT: production of stock for primary processing of flax with stable and controllable moisture of last layer. 2 cl, 4 dwg

Description

 The invention relates to agriculture and can be used in the primary processing of flax in farms and in agricultural engineering in the manufacture of complexes of machines for cleaning flax.

 The stalk of flax consists of a woody core, covered on the outside with a bark containing bast bundles. The bulk of the stem’s moisture is in the core. The purpose of drying flax before the primary treatment is to give the core rigidity and brittleness, which it acquires after moisture loss of up to 7-10%. The fragility of the core (bonfire) is needed when the stalks are broken (mechanical fracture) and scuffing.

 A known method of drying flax trusts, in which the stems are heated from the surface with heated air by convection flows or blowing a fan. The method is carried out in rigs, chamber and tunnel dryers.

 A device for drying flax trusts containing a chamber, in which a conveyor and a fan in communication with the camera are known.

 The disadvantage of this method and device is that the heating and removal of moisture goes outside deep into the stem, the outer layer is dried, bast fibers become brittle, their moistening is required before further processing. Drying chambers are bulky, with a large outer surface, a long heating period, work with a small temperature difference before and after exposure to raw materials, so their efficiency is not great and this method is not suitable for small farms.

 The aim of the invention is to increase the yield of fiber and its quality together with the possibility of applying the drying method by small farms.

 The goal is achieved by the fact that the drying agent of the linen trust uses microwave radiation and vacuum. Electromagnetic radiation evaporates moisture simultaneously in the entire volume of the stem, steam through the transverse pores of the wood goes under the bark, weakens its connection with the wood and separates it. Bast fibers, being in the zone of steam leaving the core, dry out less and their further hydration is not required. Moisture is removed from the drying chamber by a stream of air directed along the stem, which is created by a suction fan. The performance of the suction fan is greater than the volume of the generating steam entering to purge air and air entering through leaks. In addition to removing moisture from the drying chamber, the air suction creates a reduced pressure in the chamber, which reduces the temperature of vaporization and increases the pressure drop between the wood and the bark, thereby contributing to the drying of the stems and the separation of the bast from the wood. Devices for drying trusts can be continuous and batch.

 In FIG. 1 shows a continuous sectional dryer, side view; in FIG. 2 same, cross section; in FIG. 3 batch dryer; in FIG. 4 stalk in a section with steam pressure forces.

 The drying device comprises a chamber 1, a microwave generator 2 mounted on it, a conveyor 3, the upper branch of which passes through the chamber 1. In the chamber 1, entrance and exit windows for the conveyor 3 with sealing rollers 4 and a shield 5, which are pressed by a spring, are arranged on the end walls 6 to the conveyor belt 3. Inlet and outlet pipes 8 for purging the chamber 1 with air are mounted in the side walls of the chamber. The inlet pipe 7 is equipped with a shutter-regulator 9. The pipe 8 is connected to the suction channel of the fan 10.

 The continuous device operates as follows.

 The flax layer 11, moving in the direction of arrow A along the conveyor 3, lifts the upper roller 4, compressing the springs 6, enters the chamber 1 and is exposed to the microwave, which is generated by the generator 2. The camera body 1, rollers 4 and protection 5 protect the personnel from radiation and restrict the flow of outside air into the chamber. The liquid located in the wood of stem B evaporates and along the transverse pores under some pressure in the form of steam along the arrows P enters under the bark B, separating it from the wood. Achieved a double effect of drying the stem and separation of the bark with bast bundles. In this case, the bast layer is in an environment of high humidity (all the moisture of the wood passes through the bark), therefore, moistening before processing is not required, the yield of a long fiber will increase. The steam generated in the chamber 1 is removed by suction through the nozzle 8. The outside air enters through the nozzle 7, equipped with a shutter-regulator 9 and blows off the flax layer 11. The capacity of the suction fan 10 exceeds the volume of generated steam entering the nozzle 7 through leaks of external air. A certain vacuum is created in chamber 1, which reduces the temperature of vaporization and increases the pressure drop under the bark of the stem, contributing to its separation from the wood. The depth of the vacuum is regulated by the shutter 9. Flax stalks on the conveyor 3, depending on the flax processing scheme, can be located both across the tape and along it. The dried flax, moving on the conveyor 3 in the direction of arrow A, passes the second seal 4 and goes on to further processing.

 The periodic device consists of a sealed chamber 11 with a door 12 and a pipe 13 connected to the suction channel of the fan 14 and the microwave generator 15.

 The batch dryer operates as follows. In the chamber 11, through the door 12, the packaging of trusts, a bale, a roll is loaded, the fan 14 and the microwave generator 15 are turned on. Under the influence of radiation, the water contained in the stems turns into steam and is removed from the chamber 11 through the pipe 13 by the fan 14. The fan 14 has excess capacity to create a vacuum in the chamber 11, which lowers the temperature of vaporization and increases the pressure drop inside and outside the flax stem. After reaching the set humidity, which can be determined by the weight difference before and after drying, the generator 15 and the fan 14 are turned off, the dried packaging is unloaded and a new drying package is loaded into the chamber.

Claims (2)

 1. The method of drying flax trusts in a sealed chamber by removing moisture simultaneously in the entire volume of flax stems under reduced pressure created by suction of air from the chamber, characterized in that the moisture is removed by microwave electromagnetic radiation.  2. A device for drying flax trusts, containing a chamber in which a conveyor and a fan in communication with the chamber are located, characterized in that the drying chamber is provided with a microwave generator mounted above the conveyor and is made with two end receiving and output windows equipped with spring-loaded sealing chambers rollers and a conveyor belt passed through them, and in the side walls of the chamber at the level of the conveyor belt there are installed suction and air supply pipes for flax blowing, and the air supply pipe is equipped with fa st regulator.

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