| 摘要 |
<p>A method of detecting clogging of the air-feeding pipes, comprising a plurality of air-feeding pipes (15) having outlets (13) for blowing the air into a granulating section (1), and nozzles (3) formed at the central portions of the air outlets for jetting molten material solution such as molten urea and the like, wherein: (a) orifice sections (14) are provided at the lower part of the air-feeding pipes (15), post-orifice pressure take-out sections (16) are provided in the air-feeding pipes on the downstream side of the orifice sections, and a pre-orifice pressure take-out section (17) is provided on the upstream side of the orifice portions; and (b) the difference between the pre-orifice pressure and the post-orifice pressure is measured; in order to detect clogging in the air-feeding pipes based on the abnormal difference in the pressure in the air-feeding pipes. The granulation method comprises the steps of monitoring the difference of the pressure, stopping the supply of the molten material solution into the air-feeding pipes that exhibit abnormal difference in the pressure, and feeding increased amount of air to the other pipes to compensate for the stop. The detecting method suitably detects defective blowing of the air in granulating urea. When trouble occurs in the blow of the air, the granulation method stops the supply of the material solution to the defective portion but, instead, suitably increases the supply of the material solution to other injection nozzles having normal air outlets, enabling the operation to be continued yet maintaining the same productivity as that of before trouble has occurred.</p> |
