Department of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom.
Department of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom.
Int J Pharm. 2020 Mar 30;578:119114. doi: 10.1016/j.ijpharm.2020.119114. Epub 2020 Feb 5.
Roller compaction is a continuous dry granulation process, in which powder is compressed by two counter-rotating rollers. During this process, the powder feeding to the compaction zone has a significant effect on product quality. This work investigates the flow of powder from the feeding zone to the compaction zone using online infrared thermography as Process Analytical Technology (PAT) which is achieved via a specially built cheek plate (side-sealing). The powder undergoes increasing stress from the rollers when it is approaching the minimum gap of the compaction zone, which can be indirectly monitored by measuring the powder temperature. The online monitoring of the powder flow during the roller compaction helps locate the nip region and identify the effect of different roller forces on the temperature of the feeding powder. The results show that the nip region can be identified by analysing the temperature profiles from the feeding to the compaction zone. The increase of roller force results in an increasing slope of the powder temperature profile. In addition, offline X-ray CT measurement results show the increase of density along the feeding to the compaction direction, which is compared with Johanson theory under different roller forces in the roller compaction process.
辊压是一种连续的干法造粒工艺，其中粉末由两个反向旋转的轧辊压缩。在这个过程中，向压实区供给的粉末对产品质量有显著的影响。本工作使用在线红外热成像作为过程分析技术（PAT）研究粉末从给料区向压实区的流动，这是通过专门设计的侧板（侧密封）实现的。当粉末接近压实区的最小间隙时，它会受到来自轧辊的逐渐增大的压力，这可以通过测量粉末温度来间接监测。在辊压过程中对粉末流动的在线监测有助于定位咬入区，并确定不同轧辊力对给料粉末温度的影响。结果表明，可以通过分析从给料区到压实区的温度曲线来识别咬入区。增加轧辊力会导致粉末温度曲线的斜率增加。此外，离线 X 射线 CT 测量结果显示，在不同的轧辊力下，沿给料至压实方向的密度增加，这与辊压过程中的 Johanson 理论进行了比较。
