SU798451A1 - Drying plant for sawn timber - Google Patents

Description

(54) DRYING INSTALLATION FOR SAWN TIMBER

one

The invention relates to a technique for drying lumber.

Typically, wood drying plants include several continuous or batch drying chambers. They contain heat sources, centrifugal or axial fans with a system for recirculating duct ducts and air ducts with dampers. Air exchange channels are used for the organized removal of evaporating moisture from sawnwood in the form of steam and to supply small air into the chamber with content from the control corridor or ambient air, in order to maintain the parameters of the drying agent in accordance with the requirements of the technological mode.

In the timber drying practice prevails, the use of several dryers simultaneously in one unit - the drying shop.

In each continuous chamber, for the disposal of the exhaust hot air, there is a recovery unit combined with an irrigation system and exhaust air purification.

In batch chambers, the exhausted moist air is removed into the surrounding atmosphere, and the degree of saturation of the drying agent during the heating of cold lumber entering the drying process is carried out by introducing saturated steam from the steam line or from a special humidifier into the working space of the chamber.

Wood drying chambers are known which contain internal reversible fans with electric drives located at the side walls of the chamber and a traverse corridor. At the same time, the side walls of the chambers are made with wedge-shaped channels into which fans 1 are mounted,

However, in these chambers the use of hot humid air does not provide, in addition, the spent drying agent, containing various volatile substances (acetic and formic acids, esters, oils, etc.), pollutes the surrounding air.

Claims (2)

Wood-drying installations are also known, consisting of a block of chambers of periodic action. Moisturizing drying agent in the chamber. the raw lumber is rolled into which is produced by the exhausted moist air supplied from the other chambers of this installation through the recirculation system of the ducts by the fan 2. However, in these installations consisting of a block of chambers, it is difficult to maintain regime parameters in each individual chamber, since the presence of free through A canal at the bottom of the unit creates a leakage agent drying into the adjacent chambers. The drying installations for sawn timber containing several periodical drying kilns with fans with a recirculation duct system and air exchange 1e channels with flaps 3 are closest to the proposed by the technical sunshine. However, in these installations, there is not sufficiently efficient heat and mass transfer process efficiency. The purpose of the invention is to improve the quality of drying. This goal is achieved by the fact that the air ducts are interconnected by means of a common hermetic heat insulated container located outside the chambers, each chamber being equipped with a hydraulic shutter installed below its floor, and the hermetic heat insulated tank is equipped with a vapor condensation device. Ma Fig, 1 schematically shows the proposed drying installation; in fig. 2, view A in FIG. 1. The drying installation consists of several chambers I, 2 and 3 in which lumber 4 having a common body is dried. The heat-insulated hermetic container b is placed outside the chambers and through it the air-exchanging channels 7 and 8 are connected Kairaribi They have autonomously controlled dampers 9 and 10. The suction ducts 7 are connected to the vacuum zone 11 created by the fans 12, and the exhaust ducts 8 are connected to the increased pressure zone 13 in chambers 1, 2 and 3, also created by fans 1 that have a system corrected cystic air of gadfishes 14. To maintain the determined pressure in chambers 1, 2, and 3, hydraulic gates 15 are used, which are still and shaped tubes filled with liquid, such as water, and installed below the floor level of the chambers. The device for the removal of excess steam in the container b is a radiator 16, inside which coolant circulates. Drying plant works in the following way. In chambers 3, 2 and 3, raw lumber 4 is loaded at different times, and the drying process takes place in them. In chamber 1, the material is initially heated, when, according to the technological regime, the humidity of the yushka agent must be high. In subsequent chambers 2 and 3, the first or second drying periods occur, where the humidity of the drying agent must be lower than in the first chamber. In the chamber 1, the flap 9 of the air exchanging duct 7 opens and the flap 10 is closed. Due to the vacuum created by the fan 12, moist hot air from the tank 6 enters the working space of chamber 1. In chambers 2 and 3 humid air (since the drying agent in IH-IX must be dry) through the channels 8 is periodically discharged into the tank . The lack of a drying agent, if required, in the chambers is wired by external air through hydraulic gates 15. The container b is under some excessive static pressure of moist hot air, the value of which is pei-turned on by turning off or turning off the radiator 16. In chamber 1, where An overpressure of humid air can be created, the latter is removed through the hydraulic shutter I 5. Thus, in the chambers 2 and 3 the drying agent is dried, and humidification is in the chamber 1. The technological mode of the scanner is maintained at a predetermined level independently in each separately operating chamber. The use of the proposed installation has determined the autonomous operation of chambers with any coolant (flue gases are hot air), especially in calorie-free aerodynamic chambers, since in this case there is no need to use special humidifying devices, which reduces the cost of drying and improves the quality of dried lumber . Claim 1. Dryer installation for lumber, containing several intermittent drying chambers with fans with recirculated air duct system and air exchange channels with dampers, in order to improve the quality of drying and its cost, the air exchange channels are connected among themselves by means of a common sealed heat-insulated container located outside the chambers., 2. Installation according to claim 1, characterized in that each chamber is provided with a hydraulic shutter installed at a level of its floor.