Influence of liquid binder dispersion on agglomeration in an intensive mixer

To characterize the granulation rate processes in the kneading section of the twin screw granulator, separate experiments were conducted using exclusively conveying elements as the baseline in addition to different configurations of kneading elements. The configuration parameters examined were the length of the kneading section, the advance angle, and the angle direction. Granule size, shape and liquid distribution were measured. Two main rate processes were observed (1) breakage and layering, and (2) Shear elongation and layering. Breakage was dominant in the 90 configuration while shear elongation dominated in the 30 reverse configurations, with other configurations giving some combination of the two rate processes. The distinct three-dimensional (3-D) shape characteristics of granules obtained from each configuration were crucial in elucidating the dominant granulation rate process in each case. The proposed granulation mechanisms explain the events leading to particular granule attributes, but more importantly provide insight into future optimization of twin screw granulation process.

Section: Introductionmentioning

confidence: 99%

Granulation rate processes in the kneading elements of a twin screw granulator

Hagrasy

Litster

2013

“…1 4 been reported to be a consequence of uniform wetting and nucleation. 3,[5][6][7][8] Ensuring a controlled wetting and nucleation generally gives rise to controlled granule growth and breakage, which eventually leads to the formation of homogeneous granules. For poor wetting and nucleation, the granules will be immersed with uneven liquid binder content, with the large granules associated with more liquid binder than the smaller granules.…”

Section: Spray Granulationmentioning

confidence: 99%

Mapping of regimes for the key processes in wet granulation: Foam vs. spray

Tan

Hapgood

2013

“…[3][4][5][6] Systematic (experimental) studies of wet granulation were performed as early as in the 1950s by Capes and Danckwerts, 7,8 Newitt and Conway-Jones, 9 and Rumpf. 10,11 Over the decades numerous other studies have been conducted, examining the influence of the material properties such as particle size, 12 binder properties 13 and binder addition method, 14,15 to name but a few.…”

Section: Introductionmentioning

confidence: 99%

The inverse problem in granulation modeling—Two different statistical approaches

Braumann¹,

Man²,

Kraft³

2011

This article is concerned with parameter estimation for a multidimensional population balance model for granulation. Experimental results were obtained by running a laboratory mixer with sodium carbonate and aqueous polyethylene glycol solutions. Subsequently, a prescan of suitable parameter combinations utilising the experimental results is performed, and a local surrogate model constructed around the best combination. For the actual estimation of the parameters and their uncertainties two different approaches are applied-a projection method and a Bayesian approach. It is found that the model predictions with the parameters obtained through both methods are similar. Furthermore, the uncertainties in the model predictions increase as the experimental uncertainties are increased. Studies of the marginal densities of two-parameter combinations obtained through the Bayesian approach show a correlation between the collision and breakage rate constant, giving potential hints for further model development. Furthermore, a bimodal distribution of the compaction rate constant is observed.