Sušenje hrastovih lamela - deo 1. analiza procesa u kondenzacionoj sušari

Abstract

U radu je analizirana mogućnost sušenja hrastovih lamela - tankog sloja masivnog drveta u višeslojnom podu. Fokus prvog dela rada je na kondenzacionim sušarama koje su za sušenje hrastovih lamela alternativa konvencionalnim sušarama. Praćena su dva ciklusa sušenja u industrijskoj sušari i parametri sušenja poređeni sa arhivom ciklusa sušenja lamela u konvencionalnoj sušari. Istovremeno, sušenje lamela je sprovedeno u klima komori gde je primenjena viša početna temperatura. Pokazano je da se hrastove lamele debljine 5mm mogu uspešno sušiti u kondenzacionim sušarama, uz relativno kratko vreme sušenja i visok kvalitet. Sa primenjenim režimom (početna temperatura 36°C, konačna 46°C) očekivano je da ciklus sušenja traje od 2 do 5 dana, u zavisnosti od količine lamela i početne vlažnosti. Zbog velike brzine isparavanja vode i nemogućnosti sušare da je odstrane dovoljno brzo, sušenje lamela se i u kondenzacionim i u konvencionalnim sušarama odvija pri ravnotežnoj vlažnosti koja je viša od zadatih vrednosti.

The subject of this paper is to analyse the drying process of oak lamellas, which are the solid wood top layer of engineered wood flooring. The focus of the first part of the paper is on dehumidification kilns. Drying in a dehumidification kiln is an interesting alternative to conventional drying of thin solid oak wood with the aim of reaching high drying quality in a reasonable time. Drying tests were done in an industrial dehumidification kiln, and drying parameters were compared with the drying in the conventional kiln. Simultaneously, a drying test at a higher temperature was done in the programmable climate chamber. It was demonstrated that thin oak lamellas (approx. 5 mm thick) could be successfully dried in a dehumidification kiln in a relatively short time and with high drying quality. With the applied drying schedule (initial temperature of 36 °C, final temperature of 46 °C), the drying cycle will last 2 to 5 days, depending on the amount of wood and the initial MC. Due to the high rate of water evaporation and the inability of the kilns to remove it fast enough, the drying of lamellas in both dehumidification and conventional kilns takes place at a higher equilibrium moisture content than the set values.