Binders for agglomeration

Binders for agglomeration, 354,355 Bingham liquids, 104, 105, 107-109,711 Biochemical glossary, 657 Blasius equation, faction factor, 69 Blenders, in fine, 300-302 sketches, 302 power, 300... 

Most materials are briquetted or compacted by pressure alone. However, in some cases, a binder must be utilized to supplement the mechanical forces required for agglomeration. The binder has to be inert and non-contaminating to the material. Please state whether this approach would be permissible with your material. 

Relatively larger agglomerates formed than in most other methods. Limited pressure necessitates binder for adequate final strength. 

C. A. Holley, Binders and binding systems for agglomeration, IBA Proceedings, 17th Brenn Conference, August 1981. 

At certain conditions agglomeration also takes place in turbulently moving liquid suspensions. This is the case if, for example, a small amount of a second liquid is added as a binder. This component must be able to adhere to the solid particles in the suspension but must be immiscible with the suspending liquid. After its addition, spherical agglomerates form during a suitable movement of the liquid. Figure 86(a) to (h) shows schematically apparatuses that were successfully used for agglomeration in suspension. 

Another process that relies on the formation of droplets for agglomeration is shown in Figure 91. It has never gained any major industrial importance. Droplets of a liquid binder fall into a bed of powder which is transported on... 

According to Miiller and Kraft,powder mixers can be divided into two major groups. The distinguishing characteristic is the method by which particle movement is initiated and maintained. They are machines in which (A) mixing is accomplished by gravity (free-fall mixers) and (B) mixing takes place by the action of mechanical forces. Any one of these mixers, with or without modifications, can be utilized for agglomeration. For adaptation, spray nozzles for binder addition need to be installed in most mixers. 

Binder and/or lubricant selection depends on many considerations which are specific for the particular application. The additives must be compatible with the material to be agglomerated and the proposed uses of the product. For example, for pharmaceutical or food applications no toxic materials can be selected and for agglomeration of metal-bearing dusts intended for use in steel making sulfur-containing additives are normally prohibited. Many such limitations may be defined for specific materials and applications. 

K. R. Komarek, Selecting binders and lubricants for agglomeration processes . Chemical Engineeringy Dec. 4, 1967. 

If highly viscous binders, such as bitumen, honey, pitch, tar, etc., are applied, adhesion forces at the solid-binder interface and cohesion forces within the viscous material can be fully exploited for agglomerate strength until the weaker of the two fails. Highly viscous binders are often used as matrix binders (see also Sections 5.1 and 5.2.1). 

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