The term agglomerate originates from Latin (agglomerare – to accumulate, to ball up) and describes in process engineering the accumulation or “balling up” of previously loose constituents – e.g. granules or powder – to form a solid compound.¹ The terms “lumpiness” or “grain enlargement” are also used in this context. The composite achieved in this way is produced by process engineering methods such as sintering or pressing and, in contrast to “conglomerate”, is characterized by relatively uniform grain or granule sizes. Agglomerates are therefore enlarged particles formed from smaller particles or solids by the agglomeration process.

What are agglomerates?

Agglomerates are particle composites that are formed by smaller particles sticking together. In this process, the smaller particles are bonded together to form larger and stable agglomerates. This process can occur in a variety of ways, including mechanical, thermal, or chemical methods. Agglomerates are used in many industries, particularly in areas such as chemicals, food processing, pharmaceuticals, mining and environmental engineering.

The importance of agglomerates in industry

Agglomerates play a critical role in numerous industrial processes. They can be used to improve the handling of powders, increase the flowability of materials, improve the solubility of substances, facilitate dosing and increase the stability of products. Agglomerates can also have specific properties such as porosity, particle size and hardness that make them particularly suitable for certain applications.

The agglomeration processes

The agglomeration processes used to form agglomerates are diverse and vary depending on the materials to be processed and the desired properties of the agglomerates. Ebbecke Verfahrenstechnik specializes in providing customized agglomeration solutions for customers. Some of the most common agglomeration processes are explained below:

1. mechanical agglomeration

Mechanical agglomeration involves the application of mechanical force to join particles together. This can be done by rolling, mixing, stirring or kneading the particles. The process can be aided by the addition of binders to better hold the particles together. Mechanical agglomeration is often used in the food industry to produce products such as granola bars, granules or instant beverage powders.

2. thermal agglomeration

In thermal agglomeration, particles are combined by heat treatment. By heating the particles, they melt or soften at the contact points and combine to form larger agglomerates that remain stable after cooling. This process is often used to produce metal agglomerates or to solidify powdered materials.

3. chemical agglomeration

Chemical agglomeration is based on the use of chemicals to bind and agglomerate the particles. This can be done by adding binders, liquids or solutions that have a reactive effect on the particle surface. Chemical agglomeration is often used in the mining industry to agglomerate ore and improve the beneficiation process.

Applications of agglomerates

Typical examples of agglomerates in food technology are soluble coffee powder, instant powder for beverages and other convenience products. Agglomerates are also frequently used in pharmaceuticals, for example in tablets or as a thickener in liquid meals.

Agglomeration process

Agglomeration is one of the four main process groups in mechanical process engineering. In the field of agglomerates, a basic distinction is made between pressing and build-up agglomeration processes, fluidized bed granulation, mixed agglomeration and remixing agglomeration.

In sintering, the fine-grained materials to be combined are heated to enable the molecules to bond at the melting surfaces of the individual particles.

Tablets, pellets or even briquettes are produced by press agglomeration – also called compression molding.

The flocculation process, on the other hand, allows solid particles in liquids to coalesce into larger particle clusters, thus facilitating filtering.

Advantages of agglomeration

The aim of agglomeration is to improve the properties of substances – for example, by optimizing flowability or reducing dust in powders and mixtures. Agglomeration can also improve the storage and handling of materials.

Agglomerates, such as those produced by fluid bed drying, are easy to dose and ideal for stirring into water or other liquids. Due to the low content of fine dust, the hygienic conditions in the processing environment can be improved and maintenance and cleaning efforts can be minimized.

Processing at Ebbecke Verfahrenstechnik

At Ebbecke Verfahrenstechnik in Bruchköbel, agglomerates are processed in contract grinding. Using various techniques such as Centrifugal Screening and machines such as the Fine Mill, these compounds can be broken up and further processed. Contact us and let us advise you, we are glad to be there for you!