1984 年 33 巻 372 号 p. 1135-1140
To get large and uniform size granules by a closed circuit granuration process, experiments were carried out by simultaneous operation of granulation and separation in a single horizontal rotating conical vessel which has a pair of outlets at both ends.
In the above closed circuit granulation, the fine materials (CaCO3 powder) fed into the conical vessel with water droplets were granulated and separated in the vessel, simultaneously. The small granules discharged from the narrow end of the vessel were returned to the feeding point and refed with new materials. The large granules were obtained from the wide end of the vessel as the final product.
The effect of the closed circuit granulation on the quality of the final product was examined by dividing the products into three size-ranges.
(1) In the small size-range of the products (4_??_x<7mm), the closed circuit granulation was more effective than the open circuit granulation to get uniform size granules.
(2) In the middle size-range (7_??_x<10mm), the closed circuit granulation has no marked effect on size and its distribution of the products.
(3) In the large size-range (x_??_10mm), larger size granules can be obtained in the closed circuit granulation than in the open circuit granulation under the same feed ratio of binder to solid materials.