Granules from fine powder: Agglomaration

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In summary, the conversation discusses the difficulties in converting a fine powder into hard granules using a Fluidized Bed Dryer with a binder and water. The granules remain crumbly and soft instead of the desired hard product. The lack of response to the issue leads to the suggestion of using a fatty acid salt of the metal as a binder, which has high surface tension and viscosity to hold the granules together.
  • #1
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I'm trying to convert a fine powder into hard granules (1mm - 3mm dia) & was trying to use a Fluidized Bed Dryer to do it. It seems to somewhat work but the granules stay crumbly & soft rather than the hard product I need.

My protocol is to mix ~20% starch as a binder & then add water & fluidize the bed with 50 C air for about 30 minutes in the hope that the particles agglomerate.

Any tips? What other parameters are relevant?
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  • #2
I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?
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  • #3
Greg Bernhardt said:
I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?

No, I gave up on the problem. I couldn't find a way to get it to work.
  • #4
The problem may be with the binder. Thinking about it from first principles, you need a binder that will wet the metal, but has a high enough surface tension (and high viscosity would help) to hold the granule together.

If I had to solve this problem, I would be looking at a fatty acid salt of the metal you are trying to agglomerate.
  • #5

I understand your frustration with the results you are getting from your process. Agglomeration is a common technique used in many industries to create larger, more durable particles from fine powders. Your approach of using a fluidized bed dryer is a good start, but it seems that you are not achieving the desired outcome of creating hard granules.

One possible explanation for this could be the amount of binder you are using. While 20% starch may seem like a sufficient amount, it may not be enough to fully agglomerate the particles. I would suggest experimenting with different levels of binder to see if that improves the hardness of the granules. Additionally, the type of binder used can also play a role in the agglomeration process, so you may want to explore different options.

Another relevant parameter to consider is the temperature of the air used in the fluidized bed dryer. While 50 degrees Celsius may be effective for drying, it may not be high enough to fully agglomerate the particles. I would recommend increasing the temperature and monitoring the results to see if there is an improvement in the hardness of the granules.

Other factors that can affect the agglomeration process include the size and shape of the particles, the speed and intensity of the fluidization, and the humidity of the air. It may be helpful to conduct a thorough analysis of these parameters and make adjustments as needed to optimize the agglomeration process.

In conclusion, agglomeration is a complex process that requires careful consideration of various parameters. I would suggest conducting further experiments and adjusting your protocol to find the optimal conditions for achieving the desired hard granules. Additionally, consulting with experts in the field or conducting a literature review may provide valuable insights and tips for improving your process.

Related to Granules from fine powder: Agglomaration

1. What is agglomeration?

Agglomeration is a process in which small particles, such as fine powder, are combined into larger particles or granules.

2. Why is agglomeration important?

Agglomeration can improve the flow and handling properties of powders, increase the efficiency of production processes, and enhance the performance of the final product.

3. How does agglomeration work?

Agglomeration can be achieved through various methods, such as spray drying, wet granulation, or compaction. These methods involve adding a binding agent or applying pressure to form larger particles from smaller ones.

4. What are the benefits of using agglomerates?

Agglomerates have a more uniform particle size and shape, which can improve the handling and flow of powders. They also have a higher density, making them easier to transport and store. Additionally, agglomerates can have improved solubility, dissolution rate, and compressibility compared to fine powders.

5. What factors can affect the agglomeration process?

The properties of the powder, such as particle size, shape, and surface properties, can affect the agglomeration process. The type and amount of binding agent, as well as the method of agglomeration used, can also impact the final product. Other factors, such as temperature, humidity, and mixing time, may also play a role in the agglomeration process.

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