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Yes, standard high shear mixers are capable of producing submicron droplets or particles. But in large part, this is also highly dependent on the formulation itself. Apart from mixing intensity, several other factors affect particle or droplet size reduction including inherent properties of the raw materials, their interaction or chemistry, presence and type of surfactant, operating temperature, shear-sensitivity, etc. For this reason, particle size distribution can only be accurately determined through mixer trials wherein the actual raw materials are used and real process line conditions are simulated as closely as possible. In certain cases, even the same raw material sourced from a different supplier can yield significantly different results.

There are many factors we are considering when assessing the best candidate for a dry blending project. The three most common choices are our Ribbon Blender, Tumble Blender, or Vertical Blender. Each design will have specific advantages in certain processes. For example, if there are ingredients in the blend that are a small percentage of the total batch, the Tumble Blender will have an advantage over the other two candidates. If large volumes are required and the ingredients are in similar percentages in the formulation, the ribbon blender will have the advantage. The Vertical Blender would likely be the best choice if heating or vacuum is an essential part of the blending process. For further information please watch our webinar titled, "A Ribbon, Tumble or Vertical Blender- Which is Best for My Process."

There are several primary factors we consider in our effort to identify the best mixer candidate. The viscosity and the density of the material are among the most important factors to consider. Selecting a device that can provide an increased level of shear energy to the dispersion is likely to solve the problem. There are also other factors to consider as well. For example, vacuum mixing or mixing at an elevated temperature may be beneficial to generating the appropriate dispersion. Once the best candidates are identified, testing their performance with the product is a critical step in confirming the mixer selection is appropriate.

Yes we can. We are commonly helping clients in this particular situation. We will evaluate and identify the critical process requirements and use that date to specify what is required to meet your production demands.

Emulsion separation in this situation is usually a result of insufficient shear energy to generate the appropriate droplet size. Looking at both the peak shear energy and the total energy per unit mass of product are two critical factors in generating the appropriate emulsion.

We need to first determine what the rate limiting step in the process is. In some applications, it may be the amount of mixing energy required to create the appropriate dispersion. This can be solved by adding an additional agitator, or swapping the existing agitator for one offering higher shear intensity.

Processing in a mixer under vacuum or with a suitable nitrogen blanket are the best way to ensure no additional moisture from the atmosphere will be introduced to the product. Raw materials, especially hygroscopic solids, should be stored in an area that is free from moisture.

Vacuum mixing offers several advantages that can enhance product quality. It eliminates entrained air, including moisture and oxygen, which can negatively impact product stability and shelf life. Vacuum mixing often improves appearance and improves the dispersion of solids in the final product. These characteristics make vacuum mixing a preferred choice for applications requiring high-quality and stable products.

For dilatant materials, high shear can be generated with relatively low velocity, depending on the characteristics of your particular fluid.

Planetary Mixers and Multi-shaft Mixers are commonly utilized in applications where we see this fluid behavior. We rarely see rotor/ stator mixers for applications involving dilatant materials.

Yes, the Vertical Blender can be mounted on load cells and used as a weighing device.

A: The minimum batch on a VCB tumble blender will depend largely on whether you are using an intensifier bar. When considering just the mixing aspect without an intensifier bar, 1/10 of the working volume could be mixed. If using an intensifier bar, you would have to select a batch height where the product sufficiently contacts the high speed blades.

When mixing liquids that are prone to generating foam, you should look to minimize turbulence at the surface of the batch. This includes avoiding top entering agitators if they run at an appreciable speed. Low speed, anchor agitators can be utilized if the agitator is relatively large in diameter and running at a slow rotational speed.

Title 21 CFR Part 11 are regulations pertaining to records in electronic form that are created, modified, maintained, archived, retrieved, and/or transmitted under any records requirement set forth by the FDA. ROSS Mixers can be supplied with a data acquisition software package compliant with 21 CFR Part 11, ensuring that electronic records and signatures are considered trustworthy, reliable and equivalent to paper records.

This is possible depending on the material characteristics. The combination of vacuum, heat and proper agitation can accelerate drying time.

The single mechanical seal is product-lubricated, so the product must have a good lubricating properties. When using a single mechanical seal, the mixer can never be run dry. In contrast the double mechanical seal utilizes a seal barrier fluid for lubrication. In general, the double mechanical seal performs better than a single when the product is a poor lubricant, contains abrasive particles, and/or occasionally runs dry.

The most important characteristics to know to start the selection process would be:

• Batch size
• Viscosity range of the product during mixing process
• Product density
• Shear requirement or mixing intensity

Service life depends on actual operating conditions but with proper maintenance, ROSS Mixers typically remain in service for many decades.

Yes. We offer a wide range of mixers and blenders that are often customized for a particular process and application. Apart from our standard product lines, we also accept custom fabrication jobs including storage tanks, pressure vessels and reactors.

When scaling up, the total amount of energy per unit of volume is taken into consideration. Other attributes such as tip speed, batch turnover, viscosity, and liquid rheology are also taken into consideration. Ross has over 180 years of experience assisting clients in all industries and frequently assists clients with the challenges of scaling up.

The use of scrapers will depend on the product and process. Scrapers are beneficial when heating or cooling accompanies the mixing cycle. The use of scrapers in batch mixing helps improve product homogeneity and heat transfer efficiency. However, there are cases wherein scrapers are not recommended such as in the processing of abrasive applications or highly viscous, sticky materials.

Yes. In order to determine the appropriate amount of mixing, the properties of the product should be well understood, which can be accomplished by testing and collecting data at various intervals. Overmixing is a broad term, covering a wide array of phenomena but ultimately refers to overworking a product beyond its final expected characteristics.

Integrating powder induction systems with high shear mixers requires careful consideration of system compatibility, powder handling capabilities, and process requirements. Powder induction systems facilitate rapid dispersion of dry powders into liquid streams, enhancing mixing efficiency and reducing batch processing times. Choosing powder induction systems with adjustable powder feed rates, dust containment features, and compatibility with mixer configurations ensures seamless integration and consistent powder dispersion for various applications.

Temperature control can be critical in optimizing mixing processes as it often affects material viscosity, reaction rates, and product stability. Maintaining precise temperature conditions during mixing prevents thermal degradation of sensitive materials and can prevent vapor loss for products that benefit from processing at lower temperatures. Some products require processing at higher temperatures to adequately melt out components prior to dispersion. Utilizing mixers equipped with heating or cooling capabilities, along with automated temperature monitoring and control systems, ensures optimal process conditions and enhances overall mixing performance.