Purpose

Accurate and reliable feeding of small quantities of powder is crucial in many industries. It is particularly true in the case of pharmaceutical manufacturing. First, the exact dosage of highly potent active pharmaceutical ingredients (APIs) is essential. Second, due to the shift towards continuous manufacturing, processing agents must be supplied continuously. Last, with regard to personalized medicine products, small doses of API have to be processed with high flexibility. In all these applications, a few grams of powder or less per hour have to be fed, which makes processing very challenging. The common route of pre-blending causes additional effort in processing and quality control compared to direct continuous feeding, while material properties influence the performance of conventional feeders with conveying screw elements.

Methods

In this study, a novel micro-feeding system based on active volumetric displacement is investigated and compared to commercial LIW feeders of various scales. In the micro-feeder, the powder is filled into a cylindrical cartridge and pushed towards the process by a piston in a controlled manner. Tests are carried out with a free-flowing grade of lactose and croscarmellose sodium as an example of cohesive powder.

Results

At feed rates of a few grams per hour, for the investigated materials, the system has at least the same performance as conventional feeders at significantly higher feed rates. Especially at low feed rates, less fluctuations are obvious and accuracy and precision of the micro-feeder are at the same level as for the established feeding technology at rates ten times higher.

Conclusion

For the two types of investigated materials (free-flowing and cohesive), the micro-feeding system shows similar or better performance than conventional and commercially applied LIW feeders. The technology offers the potential for highly accurate, continuous feeding in the low-dose range.

中文翻译：

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新型微型喂料器与失重喂料器的对比研究

目的

在许多行业中，准确可靠地喂入少量粉末至关重要。在药物制造的情况下尤其如此。首先，高效活性药物成分 (API) 的准确剂量至关重要。其次，由于向连续制造的转变，必须连续供应加工剂。最后，对于个性化医疗产品，小剂量的 API 必须高度灵活地处理。在所有这些应用中，每小时必须送入几克或更少的粉末，这使得处理非常具有挑战性。与直接连续进料相比，预混的常见途径会在加工和质量控制方面造成额外的工作量，而材料特性会影响带有螺旋输送元件的传统进料器的性能。

方法

在这项研究中，研究了一种基于主动体积位移的新型微进料系统，并与各种规模的商业 LIW 进料器进行了比较。在微型进料器中，粉末被填充到圆柱形筒中，并由活塞以受控方式推向工艺流程。使用自由流动等级的乳糖和交联羧甲基纤维素钠作为粘性粉末的示例进行测试。

结果

在每小时几克的进料速度下，对于所研究的材料，该系统在明显更高的进料速度下至少具有与传统进料器相同的性能。尤其是在低进料速度下，波动较小，微型进料器的准确度和精度与已建立的进料技术处于同一水平，进料速度高出十倍。

结论

对于两种类型的研究材料（自由流动和粘性），微进料系统显示出与传统和商业应用的 LIW 进料器相似或更好的性能。该技术提供了在低剂量范围内实现高精度、连续喂食的潜力。