PICCELL

Real-time characterisation of the size and shape of particles in suspensions and emulsions from 1 µm to 5,000 µm with highly sensitive on-line image analysis

As a robust on-line process analysis system with integrated flow-through measurement cell, the image analysis sensor PICCELL is ideal for process stages with liquid products and particle sizes ranging from 1 µm to 5,000 µm. With soft or fibrous particles, the range of particle sizes that can be handled increases to 7,500 µm. The system can be used both for fixed, stationary installation and in a mobile rack for use in pilot plants or at varying measurement locations. Via a bypass line, a partial flow is drained from the process line and fed to the image analysis in order to characterise the particle size or particle shape. Even smallest amounts of oversize and undersize particles or individual particles with special physical properties, such as aggregates, breakage or impurities, can be reliably detected. The high-frequency recording of measured data under process-related conditions enables integrated quality inspections and optimised process control in real-time.

A high-speed camera captures the particle images of the product stream in the flow cuvette with up to 175 frames per second at a resolution of 4.2 megapixels. Laser light pulses with a duration of less than 1 nanosecond generate pin-sharp images even for the fastest particles. Thanks to the high number of captured particle images, the high-performance analysis delivers reliable measurement results with a high statistical relevance in just short analysis times. Thanks to the telecentric optics used, even transparent particles can be depicted with pinpoint accuracy and correctly evaluated in terms of their size and shape.

In order to adapt the PICCELL system to the product and the process requirements, high-pressure flow cuvettes with gap widths of 0.2 mm to 10 mm and cuvette windows with diameters from 5 mm to 30 mm are available. The cuvettes are made of V4A stainless steel (SS316), the inspection windows of hardened and tempered silica glass; they are designed for a process pressure of up to 10 bar. In order to tailor the chemical resistance to the liquid medium, nearly all commercially available elastomers are available for gaskets and tubes. The handling of the drained sample in a bypass line enables safe and reliable analysis in a closed system. Even toxic or potent pharmaceutical substances can be handled without contamination. All surfaces and materials that come into contact with the product are designed to be GMP-compliant, and the control and evaluation software also enables FDA-compliant use in regulated pharmaceutical environments.

The process-suited version of the PICCELL system is suitable both for production in large-scale plants and for pilot plants or test centre applications on a smaller scale. The system is either mounted stationary to a wall or frame or in a mobile rack. All required steps for controlling the measurement process – from sampling to the evaluation and presentation of results – can be performed manually, automated or remote-controlled. The integration in the central control system and the reporting of results are adapted to the existing communication interfaces of the control system. The information gained in real-time about the particle size distribution or particle shapes can also be used for process monitoring or process control. Rapid measurement and cleaning cycles, regular reference measurements and integrated autofocusing along the optical axis combine to deliver a low-maintenance system that is always ready to perform.