Granutools SPRL

GranuCharge

Motivation

It is well known in industrial applications involving powders and granular materials that the presence of electrostatic charges influences drastically the material flow properties. The triboelectric charges are produced during flow at the contacts between the grains. Unfortunately, the triboelectric effect is still poorly understood, even at the fundamental level, and most instruments that claim to measure electrostatics do it indirectly.

Therefore, the approach to solving practical problems due to electrostatic is mostly empirical. Moreover, reproducible electrostatic measurements are difficult to perform.

The Granucharge was developed to fill that gap in powder characterization instruments by measuring the electric charge density of a sample with a customized Faraday cup. 

Granudrum

Motivation

Our approach at Granutools is to have the best proxy for your process. A good proxy in terms of measurement method is a device able to mimic the process conditions. The stress state and the flow field of the powder should be comparable in the powder tester and in the process.

We developed the GranuDrum following this statement. Therefore, for example in the next processes, the rotating drum geometry of the GranuDrum powder tester is a good proxy: the recoater process in additive manufacturing, the rotating mixer in a pharma process, the optifiller stage in tableting, the rotary press, among others. These processes have a high flow field and a low-stress state, as shown in the image below just like in the rotating drum. The GranuDrum is a good complementary tool for the shear cell.

GranuFlow: granular material flowmeter

Semi-automated measurement of powder flow rates through apertures

Motivation

The goal of the GranuFlow is to improve the ancient funnel flow meter by removing the user dependency and extend the range of powder that would be compatible with this flow through an orifice method.

By replacing the timer with an electronic weight-scale, the engineers at Granutools removed completely the user dependency of such measurements.

They also decided to extend the range of aperture available to produce very precise results and being able to process many kinds of powder.

GranuHeap: granular material heap analyzer

Automated repose angle and cohesive index measurements

Motivation

The repose angle measurement is an essential test in the pharmaceutical field. However, the way to measure the heap angle hasn’t changed for years, and the need for a more precise and repeatable measurement method rose-up in pharmaceutical companies. The GranuHeap instrument is fulfilling this need with a repeatable, fast, and user-independent measurement.

This measurement can be correlated with the tableting process and with many other pharmaceutical processes. GranuHeap measurement allows a really accurate measurement so you can precisely compare your powders.

GranuPack

High resolution tapped density analyzer

Granular material density analyzer.
Automated tapped density and packing dynamics tester.

Motivation

The bulk density, the tapped density, the Hausner ratio, and the Carr index measurement are very popular for powder characterization because of both the simplicity and the rapidity of the measurement. Moreover, the density and the ability of a powder to increase its density are important characteristics to consider when you plan to store, transport, and process a powder.

While developing the GranuPack, the development team at Granutools decided to put the priority on three simple things:

1. The initialization protocols. The filling method can induce a lot of user dependency in a classic tap tap test. With its initialization protocol, the GranuPack can ensure repeatable and precise results with no influence from the user.
2. Automatic powder height measurement. The second source of user dependency comes from the naked eye volume measurement. With his inductive sensor, the GranuPack can guarantee a good and precise measurement of the powder’s volume.
3. The packing dynamics. Besides, from the bulk density, tapped density, Carr index, and Hausner ratio, the GranuPack also measures the packing dynamics of the powder by providing the full packing curve and the characteristic tap number n_1/2.