| 摘要 |
The invention relates to a method for expanding sand-grain-shaped raw material (1), wherein the raw material (1) falls downward through a substantially vertical heated shaft (4), which is provided with means (2) for forming a temperature profile (3) and in which a shaft flow (5) predominates, wherein the raw material (1) expands into expanded granular material (6) because of the heat transfer in the shaft (4) and the resulting granular material (6) enters a pneumatic conveying line (7) having a conveying flow (8) for further transport. In order to continuously examine the quality of the expanding process, the bulk density of the expanded granular material (6) is constantly measured, wherein if a deviation from at least one defined bulk density is detected, the temperature profile (3) in the shaft (4) is adapted automatically or manually and/or the feed of raw material (1) into the shaft (4) is reduced automatically or manually. |
