Selecting the right mixing and blending equipment for food, pharmaceutical and chemical processing

Given the cost and lifecycle of industrial mixing and blending equipment, it is important for processing equipment decision makers to consider the full range of equipment options available and select the best fit for their specific application. Because mixing and blending equipment can be in operation for decades, the specifications that drove previous equipment selection may now be outdated.

Mixers vs. blenders: What is the difference?

The words “mixing” and “blending” are used interchangeably at times, however the processes differ. Mixers and blenders accomplish a similar objective: combining materials. However, they do so differently. Mixers use an agitator to mix materials together and blenders use a tumbling action to blend materials.

There are seven primary considerations for choosing mixers and blenders:

1. Feeders into and out of the machine should be considered because the speed and loading techniques for inflow and outflow will impact which machine will perform best, as well as the throughput.
2. Material composition is a primary consideration because the composition of process materials including the viscosity, density and granularity will guide specifications, customizations and other decisions for mixers and blenders.
3. Chemical processes also impact equipment choices due to the processes that will take place during combination, changing the characteristic of the materials and creating reactions that impact the internal environment of the equipment along with the surrounding area.
4. Line dedication in the facility is an important consideration. Whether the production line is multipurpose or dedicated will impact the operation and cleaning of the machines, especially if switching batches and recipes regularly.
5. Site requirements must be considered when selecting equipment. These include safety, floorspace availability, nearby machines and other physical aspects of the space where the mixer or blender will operate.
6. Durability and precision impact the performance and service life of mixers and blenders and should be considered up front. These factors include accelerated wear and tear, maintenance requirements and the potential for diminishing quality.
7. Business trajectory should also be considered. Changes in formulation, chemicals and materials technology advancements, as well as company growth, may change the long-term impact of the investment in mixing and blending equipment.

Customization is also an area to consider for industrial mixers. Selecting the right agitator and trough is the most important step in mixer design, however customization will enhance mixer performance. Common customizations for mixers include choppers, sprayer or injection designs, counterweighted doors, main shaft seals and discharge features.

Outside of standard considerations that reach across industries, there are specific considerations that are unique to equipment for food and beverage, pharmaceutical or nutraceutical, and chemical processing applications. These range from regulatory requirements to unique operating parameters. This article explores those applications and how to select the best mixing or blending units for each.

Mixing and blending considerations for food and beverage applications

Within food and beverage processing, there are myriad sub-applications that have their own unique requirements impacting equipment selection. For all food and beverage applications, however, sanitation is paramount. Mixing and blending equipment must be absolutely clean in order to avoid contamination, potential bacteria growth and product quality degradation.

Look for equipment that has smooth, welded finishes on all parts both inside and outside of the mixer or blender. In addition to the finish, there should be no bolts, crevices or other areas where food particles might get lodged. Mixers and blenders should also offer access and easy viewing of surfaces for cleaning and inspection personnel. It should not require intensive training for someone to learn how to thoroughly clean a mixer or blender. Gaskets and seals should also be airtight to prevent powders from escaping, however they should also be easy to replace when they are worn.

3-A Authorization is also a must for equipment in facilities that process food and beverages. The 3-A Authorization is a certificate program that represents the pinnacle of quality for hygienic standards based on ANSI requirements. The terminology for mixing and blending equipment is extremely important. The only way to make sure that the equipment meets 3-A standards is to look for 3-A Authorized and not “3-A compliant” or anything other than 3-A Authorized.

Although there are many specific food and beverage applications, horizontal mixers, fluidizing paddle mixers and double-cone blenders are strong-performing equipment for food processing.

Selecting a mixer or blender for pharmaceutical and nutraceutical processing

Precision is the key aspect for pharmaceutical and nutraceutical processing. Every mix must be precisely the same — there is no room for error. Consistently and accurately combined ingredients are important for product quality and user safety. For mixing pharmaceuticals, batch processing is the only way to achieve the necessary precision. Inflow, outflow and mixing times must be customized to the ingredients and materials being processed.

Sanitation is as important in pharmaceutical processing as it is in food and beverage processing. Features that make cleaning and inspection easy, as well as those that prevent contamination, are required for quality processing of both pharmaceutical and nutraceutical products.

V-cone blenders and horizonal mixers offer the features and performance required for processing pharmaceutical and nutraceutical products.

Considerations for mixing and blending equipment in chemical processing

Chemical mixing and blending considerations will vary based on several variables including temperature, sanitation and precision requirements. However, temperature control is a top consideration when selecting chemical processing equipment due to chemical reactions that may take place during the mixing or blending process. For exothermic chemical reactions, cooling jackets should be installed to control the high temperatures produced. Conversely for endothermic reactions, heating jackets or other heating mechanisms should be employed to keep mixes at the necessary temperature.

The safety of the environment surrounding the processing equipment is also an important factor in chemical processing. Classified processes and materials will require explosion-proof components including electrical parts, valves, motors and safety switches. Steps in selection and customization should also be made to ensure that dangerous fumes or dust cannot escape the equipment and cause harm to those working in the facility. Often, reactionary materials require an isolated mixing room which will impact the types of vendors to work with. Those equipment makers with extensive experience in setting up safety rooms will be able to consult on site specification and installations to ensure facility safety needs are met.

Common equipment that performs well for chemical applications include horizontal mixers and fluidizing paddle mixers.

Partner wisely

Experienced vendors can help with different techniques to optimize processing for application-specific requirements. Working with a supplier who can provide support and consultation during the specification and selection stage, as well as whole lifecycle support, creates the best opportunity for mixer and blender performance.

Look for an equipment partner who can supply mixers and blenders with the features and customizations for the application, as well as one who can provide lifecycle support and aftermarket service. The ideal partner will provide value and innovation for their customers’ food and beverage, pharmaceutical or chemical processing applications.

Bill Noonan has worked in sales at Marion Process Solutions for more than 23 years. A graduate of the University of Northern Iowa, Bill is a self-proclaimed process junkie who loves seeing and discussing the manufacturing process. Founded in 1938, Marion Process Solutions is dedicated to delivering custom-manufactured processing solutions to companies in the food, nutraceutical, mineral, plastic, chemical and biomass industries. With process solutions installed in over 75 countries on six continents, serving hundreds of global Fortune 1000 companies, the Marion brand serves as the standard of excellence in the bulk material handling industry.  

MARION PROCESS SOLUTIONS

www.marionsolutions.com