Grūdų džiovinimas kintamu oro srautu

Abstract

Straipsnyje aprašomas naujas energijos taupymo metodas džiovinant grūdus kintamu oro srautu. Metodo esmė yra tai, kad džiovinimo metu mažėjant drėgmės atidavimui iš grūdų yra mažinamas ir per grūdus praeinančio oro debitas. Reguliuojant pučiamo oro kiekį aktyviosios ventiliacijos įrenginiuose, geriau panaudojamos oro absorbcinės savybės ir atitinkamai sumažinama ventiliatoriaus naudojama galia. Elektros sunaudojimas (palyginus šį džiovinimo būdą su tradiciniu, kai oras tiekiamas nuolat) gali sumažėti iki 40 %. Tyrimams naudoti ‘Roland’ miežiai, kurių pradinis drėgnis 25 ir 30 %. Nustatyta, kad optimalus pradinis oro debitas 800 m3/(t · h). Grūdų džiūvimo metu oro debito mažinimas apibrėžiamas lygtimi y = 969,85e–0,0114x, R2 = 0,8088.Pateikta sukonstruoto ir pagaminto eksperimentinio įrenginio schema. Nustatytas oro srauto intensyvumas ir drėgmės absorbavimo dinamika džiovinamų grūdų sluoksnyje

A new energy saving method for grain drying is presented. The grain drying technology, changing the airflow blown through grains, has never been investigated in Lithuania, since there were no equipment to change the whirls of three-phase changing current electric engines. Now, when the equipment to change the frequency of the three-phase current, is available, there is a possibility to regulate the spinning frequency of grain blowers. The essence of the method is that during the drying period, when the moisture removal decreases, the air debit flowing through grains is also reduced. Barley ‘Roland’ grains of the initial moisture 25% and 30%, were used in the study. They were dried by changing air debit, in order to avail the absorption features of the air. When grain starts to dry, the airflow is reduced during the drying period, and the relative humidity flowing out of grains also decreases. The optimal initial air debit was 800 m3/t · h. The reduction of air debit during the grain drying period is expressed by the function y = 969.85e–0,0114x, R2 = 0.8088.A scheme of the constructed and produced experimental equipment is presented. The intensity of airflow is established. The dynamics of moisture absorption in the drying grain layer is established