1) 写真3-1のような背の高い乾燥ハウス内に循環式乾燥機を設置し，太陽熱で加熱されたハウス内温熱空気を乾燥機が吸引し，穀物層を通したのちハウス外へ排風するという方式によって，直接石油を使うことなく穀物を乾燥する実用規模の実験を昭和57年と58年度に実施した。2) 日射量や乾燥機への穀物投入量，もみの初期含水率などがそれぞれ異なる場合について上記の乾燥を繰返し実施したが，その平均の乾燥速度はおおむね 0.4～0.5%h であり，晴天ならば日中1～2日間の通風で乾燥は終了できた。3) 穀物の乾燥速度は日射量にほぼ比例して増加し，かつ集熱量とも密接な関係があることがわかった。乾燥ハウス内で稼動する乾燥機台数をふやすとハウス面積当りの穀物量や通風量が増加し，一定時間内で蒸発する穀物水分量も増加する。4) 穀物乾燥1回当りの乾燥所要時間は除去水分量に比例するので初期含水率が高いほど多くなる。したがって，含水率の低いときに収穫すると乾燥時間は節減できる。5) 本実験の範囲では集熱面積や乾燥機内通風面積の乾燥速度への影響は微小であった。6) 集熱量は積算日射量に比例して増加し，穀物水分蒸発量は集熱量に比例して増加する。穀物水分 1Kg を蒸発させるのに費された付加熱量(集熱量)は約 1000kcal であった。7)写真3-1のような背の高い乾燥ハウスの集熱可能量は従来のビニールハウスに比べて著しく多かった。そのため 25m² の乾燥ハウス内で循環式乾燥機2台の同時運転による太陽熱利用の穀物乾燥が可能であった。
1) In 1982 and 1983, using circulation‐type grain dryers in a tall firon‐covered greenhouse shown in photo 3-1, an experimental study on drying of paddy rice with solar energy was conducted on a practical scale. In this system, the hot air in the tall firon-covered greenhouse heated by solar energy was forced to flow through the grain layer out into the atmosphere. 2) Drying test of paddy rice was repeated under various conditions such as solar radiation, grain volume, initial water content, etc. From the results, the average moisture reduction rate was calculated to be about 0.4 ～0.5%/h, and in fair weather, paddy rice was dried sufficiently by forced air ventilation during the daytime in 1 or 2 days. 3)The moisture reduction rate of grain increased almost linearly with the increase in solar radiation, and was closely related to the amount of solar heat colleced. With increase in the number of dryers in operation, the amount of air ventilated increased. As a necessary consequence, the amount of grain which can be dried per unit floor area increased, that is, that amount of water evaporated from grain per unit time increased. 4) The time required for drying grain was proportional to the amount of water to be evaporated. Therefore, when grain with low moisiure is harvested, the drying time will be shortened. 5) Within the range of the present experimental conditions, the moisture reduction rate was affected very slightly by the heat‐collecting area and the area of air within the dryer. 6) The amount of solar heat collected increased in proportion to the amount of solar radiation, and the amount of moisture evaporated from the grain increased in proportion to the amount of solar heat collected. The sum of energy (the amount of solar heat collected) required to evaporate 1 kg of moisture in grain was about 1000 kcal. 7) It was found that the amount of solar heat collected by the tall firon-covered greenhouse is remarkably larger than that collected by the conventional vinyl-covered greenhouse. This enabled two circulation-type grain dryers to be operated simultaneously for drying the grain without using petrolem in the firon‐covered greenhouse, having a floor area of 25m².
雑誌名
三重大學農學部學術報告 = The bulletin of the Faculty of Agriculture, Mie University
巻
70
ページ
65 - 78
発行年
1985-03-01
ISSN
0462-4408
書誌レコードID
AN00234337
フォーマット
application/pdf
著者版フラグ
publisher
その他のタイトル
Artificial Drying of Grain with Solar Heated Air (Part III) : On paddy rice drying with a circulating type grain dryer utilizing solar energy
太陽熱利用による穀物の人工乾燥 (III) : 循環式乾燥機による太陽熱利用もみ乾燥について
AN002343370007004.pdf
(946.78KB)
