Lasentec

Stream scanning Brinkmann, Glimet, Goulter, Dantec, Erdco, Faley, Flowvision, Hiac/Royco, Kowa, Lasentec, Malvern, Met One, Particle Measuring Systems, Polytec, Procedyne, Rion, Spectrex 0.2-10,000 lm O.l-lOg (also on-line)... 

In the Lasentec instruments a chord-length distribution is generated, from a rotating infrared beam, and this is converted to a size distribution. Since highly concentrated systems can be interrogated this system can be used for on-hne size analysis. 

Lasentec time-of-flight analyzer, 18 150 Laser ablation... 

Menning M, Ju TR, Kim D. Monitoring In-process Particle Behavious During High-Shear Granulation with the Lasentec D600L Focussed Beam reflectance Measurement (FBRM), Lasentec Technical Note, March 2005. 

CSM has coupled the FBRM with a second probe, the particle video microscope, PVM (Lasentec/Mettler Toledo), which consists of six illuminating near-infrared lasers (850 nm) that are transmitted into the sample. While the FBRM provides precise quantitative tracking of the chord lengths, the PVM probe provides qualitative images of the hydrate particle size and degree of agglomeration. The size range scale of hydrate particles that can be measured with the PVM probe is 10-300 i,m. 

Figure 6.8 Schematic of the FBRM probe tip (a), and chord lengths (b). (Reproduced, with permission, from www.lasentec.com.)...

Objectives determine desaturation rate and In situ FBRM Lasentec M200... 

Lasentec Focused Beam Reflectance Measurement (FBRM)... 

Lasentec Labtec 1000 is a laboratory instrument that covers the size range from 0.7 to 250 pm in 28 size channels. The data are generated as scanned counts an empirical frequency distribution created from classification of chords from randomly oriented particles. Software can convert these chords to a spherical equivalent distribution on the assumption that the chords were generated from an assembly of spherical particles this software contains a filter system to reject improbable data that would tend to skew the distribution to a coarser size. A discrimination... 

Lasentec Partec 100 was found to give reasonably accurate data for the chord length distribution of sherical particles but the accuracy deteriorated progressively as the shape became more ellipsoidal [123],... 

Lasentec s Focussed Beam Reflectance Measurement Model (FBRM M400L) operates at a wavelength of 791 nm and the beam rotates 75 s at a peripheral speed of 1.9 ms .to describe a circle of diameter 8 mm. It has been used with a 3D-model of chord length distribution for particles of a general shape as well as particles with the same shape but different sizes [124]. The focal point can be changed in the axial position but it is... 

The Lasentec particle/droplet size analyzer can be used for laboratory and in-line analysis in the +1 pm size range over a wide range of operating conditions. 

Lasentec, Laser Sensing Technology Inc., 15224 NE 95th StreeL Redmond, WA, 98052, USA, (206) 881 7117)... 

Worlitschek, J. Mazotti, M. Choice of the focal point position using lasentec FBRM. Part. Part. Syst. Charact. 2003, 20 (1), 12-17. 

Barrett, P. Glennon, B. Characterizing the metastable zone width and solubihty curve using Lasentec FBRM and PVM. Chem. Eng. Res. Des. 2002, 80 (A7), 799-805. 

A generalized schematic diagram for feedforward/feedback control of particle size in a continuous or semicontinuous crystallizer, such as that in Fig. 7-5, is shown in Fig. 7-6. The measurement device can be most easily envisioned as an in-line particle size analyzer such as a Lasentec focused beam reflectance measurement (FBRM), but it could also be a sampler/ offline device combination (even a plain microscope). The most common variant on this control schematic would be elimination of feedforward control, and perhaps of the fines trap as well. 

Lasentec (in-line) Mean (p-m) = 62 — 19.5 (seed level in %) +- 0.026 (initial cool-down period in minutes)... 

As indicated by both measuring devices, seed level is determined to be the most critical parameter affecting the final mean particle size. Within the range of seed level for this study (1 + 0.5 wt%), with a 0.5 wt% increase of seed, the mean particle size will decrease by 10 p-m (0.5 19.5), as predicted by the Lasentec model, and by 12 p,m (0.5 24), as predicted... 

For the output variables, as shown in Figs. 9-15 and 9-16, the filtration time data correlated well with mean particle size (chord length) and the level of fines by Lasentec FBRM measurement and optical micrographs. This correlation enabled direct feedback of process performance (cake filtration resistance) based upon FBRM measurement. 

---