Lenterra Inline Rheometer (LIR)September 8, 2021 2023-08-09 17:15
Lenterra Inline Rheometer (LIR)
Lenterra Inline Rheometers (LIR)
Majority of pharmaceutical, food and other processes involving fluids, suspensions or powders require inline control to get a high quality product. The Lenterra Inline Rheometer (LIR) is an in-line process analytical technology that provides real-time measurements of flow force, shear rate and temperature to calculate critical process parameters (CPP) such as shear force, shear rate, wall shear stress or viscosity.
Depending on configuration, LIR consists of one or two Lenterra’s sensors (Drag Force Flow (DFF) or RealShearTM), an LOI optical interrogator and a host computer with control, measurement and data processing software. The probe placed in a desired location within the processing equipment is connected to the interrogator via fiber-optical cable. To install the probe into an apparatus, an adapter is required.
There are two basic types of LIR configurations that are determined by the type of the interrogator – a one channel LOI-2F and a two channel LOI-4F. There are total of six different configurations of LIR specified below. They are customizable, and could be converted one into another by replacing the sensor. Each configuration includes a rugged laptop pre-installed with measurement and post processing software. The LENFLOW measurement software supports all LIR configurations.
This basic LIR configuration includes one DFF sensor that can be placed in various places inside the processing equipment, for example next to an agitator blade of a mixer as depicted in the figure. Depending on the flow speed and nature of the material, a DFF sensor with required sensitivity should be selected. A standard or custom adapter can be used.
This configuration can be used for measuring flows of any type of the material, liquids or powders, slurries or gases.LIR-D directly outputs temperature and flow force, as well as FPM and PCF metrics that characterize the densification and cohesiveness for powder flow, or flow velocity and viscosity for liquids.
This configuration is used for measuring wall shear stress exerted by liquids on the construction wall. The example on the figure illustrates installation of the sensor through a side port of a bioreactor or mixer. The sensor may also be installed through a pipe wall, or used with installed inline flexible T-Junction or flow cell.
This configuration is intended for use with liquid materials which do not contain a particulate phase. LIR-R outputs wall friction force, wall shear stress and temperature. For rotor-stator mixers, it also outputs viscosity.
The configuration includes two DFF sensors and can provide process signature for two localities inside the processing equipment. It is especially useful for investigating uniformity of the processing over the volume. In a mixer or granulator one DFF sensor can be positioned near the agitator blade, and another one in the top of the flowing material, as shown in the picture. By comparing process signatures from the two probes one can judge about efficiency of the mixing. The probes may be installed from the lis or the wall of the vessel. Various types of adapters are available or a customer adapter can be developed.
LIR-DD can be used in any type of material. For each sensor respectively, LIR-DD outputs are same as for a single sensor configuration LIR-D.
A configuration that is designed for monitoring processing of liquids. A RealShearTM sensor with a non-invasive probe that effectively replaces a small part of the vessel wall, measures wall shear stress, and a DFF sensor inside the volume provides a flow force process signature. These two measurements independently characterize viscosity of the material and the friction force on the wall that can be an important measurement in determination of the effect of the process parameters such as RPM on the stress limit.
This configuration is intended for use with liquid materials which do not contain a particulate phase. For DFF sensor LIR-DR outputs a same in a single sensor configuration LIR-D, and for the RealShearTM sensor, the outputs are same in a single sensor configuration LIR-R.
A LIR configuration that is designed to monitor the state of liquid material at two different points of the processing line. In an example on the figure, one RealShearTM sensor is used to monitor wall shear stress on the wall of the mixer, and another one – in the output line of the connected peristaltic pump. In another similar application, one RealShear sensor is install inside the peristaltic pump, and another – into the plastic tubing downstream (see the application note for detail).
This configuration is intended for use with liquid materials which do not contain a particulate phase. For each sensor respectively, LIR-RR outputs are same as for a single sensor configuration LIR-R.