CS250812B1 - Equipment for convection periodic drying of timber and wood blanks - Google Patents

Abstract

The device solves the arrangement of circulating overpressure fans 6, which are placed in front of the heating element /4/ and in front of the intake pipe /8/ and the ventilation pipe /9/. The pipes are connected to the recuperation device /11/ and the circulating overpressure fans /6/. The heating element /4/, the humidifier pipes /7/, the pipes and the recuperation device are connected to the control regulation circuit.

Description

250812 2

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for convective periodic drying of timber and blanks of wood-like shapes, which are made of woods of different weight, including exotic woods, with multiple air recirculation with heat recovery. Nowadays, the artificial drying of the timber and blanks is provided in chamber or channel driers, where the drying environment created by the circulation of air changes during the transition of the cage the rusty state according to the constant enthalpy and in a certain state of saturation leaves the atmosphere.

Convection drying process. Wood assortments are often accompanied by an air change, especially in the winter months, by a drop in the drying environment temperature, which affects the temperature stability in the dryer environment and thus the drying environment parameters, entering the material layers or cages, which is quite a considerable drawback of the known dryers.

Devices in which such a method of drying is carried out demanding the arrangement of individual elements such as suction and vent chimney flaps, circulating fans, as well as an increase in the heat input to heat the intake air, thereby increasing the specific heat consumption in practice it ranges from 5,000 to 10,000 kJ kg of evaporated water.

Disadvantages of current devices are eliminated by the convection periodic biscuit and wood cutters.

The essence of the device according to the invention is that the circulating pressurized fan is arranged upstream of the heating bodies and in front of the suction line and the vent line for the discharge of saturated air, the suction line and the ventilation line being connected to the recovery device. Circulating overpressure fans, heating elements, humidifiers, air intake ducts, ventilation ducts, including recuperation devices, are interconnected to the control regulation circuit. The advantages and at the same time the greater effect of the invention are manifested in the fact that they meet the requirements of current technologies that require reduced specific heat and power consumption in wood drying, which is one of the basic technologies in woodworking. The various technical elements of the device according to the invention are arranged so as to provide multiple air circulation by the fact that the fresh atmospheric air is preheated by the outgoing, partially saturated air in the recuperator, which goes into the atmosphere.

The gaseous drying environment, after passing through the material cage, changes its state and restores it with the aid of a heat exchanger device so integrated. In the apparatus, a specific heat consumption of less than 4,600 kJ / kg of evaporated water is achieved and the uniformity of the drying environment parameters, i.e., temperature and relative humidity of the air, is maintained by periodically varying the drying cycles.

1 is a schematic view of the apparatus shown in the accompanying drawing, wherein FIG. 1 is a side elevation view of the dryer and FIG.

The device according to the exemplary embodiment of the drawing consists of a supporting jacket of the dryer, which isolates the dryer space from the outside from the inside, in our case by an aluminum sheet, from the outside by a galvanized steel sheet. The dryer has a new structural arrangement of the construction panels £ a so-called modular solution for the removal of leaks and thermal bridges, it also allows operation without roofing. In the dryer housing 1 there are two-leaf hinged doors on the charging and export side, 3.

Claims (1)

3 250812 Heating bodies for heating the drying environment are located in the fan chamber and their number corresponds to the heat output of the respective drying stage. In the ventilating space on the ceiling, the circulating pressure ventilators 6 are located in the individual steps to procure air in the direction of the simple arrows. Moisture treatment of the drying environment is located under the heating elements 4 along the length of the drying chamber dampening the pipe 2. Dampening is controlled by automatic regulation depending on the psychrometric differentiation. To replace the saturated air with clean, non-saturated air, the air intake duct 8 and the exhaust duct 9 are located partially outside and inside the dryer. The regulating flaps 10 are connected to the actuator and are designed to control the amount of vent air. The intake ducts 13 and the ventilation ducts 9 are connected by a recovery device 11 which consists of two heat exchangers, a pump, connecting fittings and a pipe, as well as providing a multiple circulation of the drying environment. The drying process is arranged according to the parameters of the drying environment, i.e. the temperature and the relative humidity of the air. Their maintenance on the prescribed values is ensured by automatic regulation of the drying process controlled by psychrometers placed on the side of the marble, which are not drawn on the pictures. The dryer is equipped with a semi-automatic control or microprocessor to control the drying process. Drying in the described device takes place in such a way that fresh in the preheated air recovery device 11 is fed into the ventilator space 2 through the intake manifold 2 where it is mixed with heated, partially water vapor saturated air and flows through the cage 12, removing the vaporized vapor from its surface layers. moisture, thereby gradually saturating with water vapor. According to the desiccation conditions required, the saturated air is either ventilated through the vent line 9 and mixed in part with fresh intake air from the intake manifold 8 air. This event is repeated all the time, thus ensuring a multiple circulation of the drying environment. In the case of low air saturation, the air is moistened by the damping tubes 7. In particular, the invention is based on a new technical solution of the device, where repeated air circulation is required with simultaneous heat recovery, while reducing the tightness of the dryer and economically advantageous operation. The device according to the invention provides for the restoration of the working mixture during drying, it is suitable to use it at temperatures of drying environment up to 100 ° C under any drying conditions, drying of exotic and European woods of weight. SUBJECT MATTER The convection periodic drying machine for timber and wood blanks is a modular, thermally insulated panel construction with built-in doors, inter-intermediate, circulating overpressure fans, heating elements, air ducts and suction air heating as well as a psychrometer. that circulating pressurized ventilators (6) are located upstream of the heating bodies (4) and upstream of the suction line (8) and the exhaust air duct (9) for suction air, wherein the suction line (8) and the vent line (9) are connected to the recovery device (11) and circulating overpressure fans (6), heating bodies (4), damping tubes (7), suction lines (8), air ducts (9), including recuperation devices (11) are connected to the control regulation circuit . 1 drawing