The effect of air flow on drying fodder on drying systems | Vpliv pretoka zraka na sušenje krme na sušilnih napravah

English. Drying grass fodder in Europe’s Alpine countries is becoming increasingly important due to positive effects on the fatty acid composition of milk. A proper approach and technology of fodder drying can raise its quality to the level of grass silage. In principle, drying fodder means extracting water from fodder by means of ventilation – the air, the key to the speed of drying. Besides low relative air humidity, its flow rate through the fodder is also important. In the literature, the lower- and upper-bound limits of air flow rates can be found, with a difference of 85 % between the two. The article describes a test, measuring energy consumption and the efficiency of drying at a low air flow, often used in practice, and a high air flow. It was found that a high air flow results in 38 % higher energy consumption per kilogramme of extracted water, compared to a low air flow. The executed test has proved that drying at a higher air flow will not have a proportionally greater effect.

Slovenian. V alpskih državah Evrope sušenje krme s travinja postaja vedno bolj pomembno zaradi ugotovljenih pozitivnih učinkov na  maščobno kislinsko sestavo mleka. S pravilnim postopkom in tehnologijo dosuševanja krme se lahko kvaliteta dvigne na primerljiv nivo travnih silaž. Sušenje temelji na odvzemu vlage iz krme s pomočjo prevetrovanja – zraka, ki je ključen za hitrost sušenja. Poleg nizke relativne vlažnosti zraka je pomemben tudi njegov pretok skozi krmo. V literaturi se navaja spodnja mejna vrednost pretoka zraka in zgornja mejna vrednost, pri čemer je razlika 85 %. Članek opisuje izvedeni eksperiment merjenja porabe energije in učinkovitosti sušenja pri običajno v praksi uporabljenem nižjem pretoku zraka in višjem pretoku zraka. Izkazalo se je, da pri višjem pretoku zrak porabimo za 38% več energije na izločen kilogram vode, kot pa pri nižjem pretoku. Izvedeni preizkus dokazuje, da sušenje z velikim pretokom zraka ne prinese enako večji učinek.