New Magnetic Mixer Saves Energy While Maximizing Product Yield
Hygienic and industrial processors are always looking for ways to mix their product more effectively. With the right industrial mixer machine increasing product yield and blending until the last drop, processors can quickly realize additional profit.
Servicing is another consideration when purchasing a mixer. If you can achieve more uptime thanks to low-wear bearings that are easy to maintain, you have a competitive advantage over your competitors.
This article will discuss various mixing technologies and highlight the LeviMag® series of aseptic magnetic mixers, a unique product offering from CSI, Master Distributor for Alfa Laval. The LeviMag's features and benefits — such as energy savings and maximized product yield — will be explored in detail, as will the use of this mixer for hygienic processing applications in the pharmaceuticals manufacturing and food & beverage processing industries.
What is Industrial Mixing?
Modern industrial processing almost always involves some form of product mixing. With the right type of mixer, it is possible to mix a solid, liquid, or gas into another solid, liquid, or gas, with the outer blades rotating in one direction. It should be noted, though, that efficient mixing can be difficult to achieve on an industrial scale. A great deal of engineering effort goes into designing and improving mixing processes.
Mixing of liquids frequently occurs in the hygienic processing industries. Industrial-scale mixers are commonly used in the food & beverage processing, dairy, pharmaceutical manufacturing, and biotechnology industries.
Definition and Importance
Magnetic mixing is a cutting-edge industrial mixing technology that leverages magnetic fields to mix and blend materials. This innovative mixing method is particularly advantageous for applications where traditional mixing technologies fall short. Magnetic mixing is widely adopted in various industries, including biotech, pharmaceuticals, food processing, and cosmetics, due to its efficiency and effectiveness. By utilizing magnetism, this mixing technology ensures thorough and uniform mixing, making it an essential tool in modern sanitary processes.
Mixers are used for a variety of applications:
- Improve product quality
- Coat particles
- Dissolve soluble solids in liquids
- Blend different types of powders
- Alter material properties
- Maintain homogenous media
- Liquid/liquid blending
- Heat transmission
- Fermentation
- Suspension
Industrial mixing may be done in several different ways: in batches (sometimes referred to as in-tank), in-line (sometimes referred to as continuous) with the process, or with the help of static mixers. There is a wide range of technologies used in industrial mixers that are designed for hygienic applications.
Some of the most common mixing technologies include the following:
Types of Mixers for Processing
1. Rotary Jet Mixers
Designed for use in the brewery, beverage, dairy, personal care, and biopharmaceutical manufacturing industries, rotary jet mixers effectively handle:
- Liquid mixing
- Gas dispersion
- Powder mixing
- Tank cleaning
While not a common type of mixer, rotary jet mixers are somewhat unique in that they may also be used in cleaning applications. Because they use the flow and pressure from circulation or transfer pump, these mix in-tank without the need for an agitator. Consider the rotary jet mixer where an agitator will not fit or is not practical (existing tanks, limited clearance, eliminate penetrations, and seals).
2. Eductors
Eductors are jet-like pumps that do not require any moving parts to mix together either liquids or gases.
Instead, they use their physical structure to transfer energy from one fluid to another via the Venturi effect.
Eductors are frequently used to increase fluid shear and agitation in tanks.
3. Powder Mixers
Commonly used in the dairy, food, and beverage industries, powder mixers are shear mixers that are used to mix powders into liquids.
Powder mixers are commonly used to mix items such as:
- Thickeners and gums
- Milk Powder
- Cosmetics
- Sweeteners
- Flavors and colors
- Salt
- Buffers
- Cocoa
4. Ribbon Mixers
Ribbon blenders are widely used for effective low shear mixing of a variety of substances from dry powders to very viscous pastes, creams to meat, and almost everything in between. Most Ribbon Blenders are a u-shaped trough with one or multiple helical agitators or “ribbons” that blend, fold, and agitate products using both an axial and radial motion, with the outer blades rotating in one direction. In ribbon blenders, the inner blades rotate in the opposite direction to the outer blades, facilitating material movement and achieving a more thorough blend. There can be variations on this design where the agitator could utilize paddles or plows for mixing.
Ribbon mixers are commonly used to mix items such as:
- Cake mixes
- Cereal
- Cocoa
- Cosmetics
- Flavorings
- Gelatin
- Instant formula
- Medications
- Pet food
- Salad dressings
- Seasonings
5. Turbine Mixers
Turbine mixers use an impeller to mix different types of liquids inside a tank. Different varieties of turbine mixers are available, depending on the nature of the material being mixed (e.g., mixing two liquids, or dispersing gases into liquids).
Turbine mixers are commonly used to mix items such as:
- Oil mixing in food storage
- Flocculation in water treatment
Overview: The Alfa Laval Levimag Magnetic Mixer
is a Swedish company, founded in 1883. The company's products are used to heat, cool, separate, and transport various materials, including oil, chemicals, water, beverages, food, starches, and pharmaceuticals.
Alfa Laval is a premier supplier of the hygienic pumps and mixers used in CSI process systems.
LeviMag magnetic mixer is designed to mix and agitate liquids inside process tanks and vessels and is primarily used in high purity applications within the pharmaceutical manufacturing industry.
The LeviMag operates on the following principle. A radial impeller installed inside a tank rotates via the torque coming from a magnetic coupling attached to a motor. This turbine creates a mixing of the fluids inside the tank.
Standard LeviMag Mixer
The standard LeviMag mixer offers effective mixing for multiple processes within the dairy, food, and beverage industries where a hygienic and aseptic design is required (e.g., in sterile storage or buffer tanks). It is available in five sizes, with mixing speeds ranging from 10 to 600 RPMs.
This provides greater process flexibility in handling a wide range of fluid types and mixing duties, including both high-intensity mixing and the gentle combination of products. Due to its compact design, the LeviMag is also an obvious choice for applications requiring low-level agitation.
LeviMag UltraPure
The LeviMag UltraPure magnetic mixer offers effective mixing for multiple processes within the pharmaceutical manufacturing and biotechnology industries.
This mixer is ideal for mixing serums, vaccines, plasma fractions, bacteria, cell cultures, APIs, and other applications where there is a high demand for hygienic and aseptic design.
The LeviMag UltraPure mixer is available in five impeller sizes ranging from 100 to 300 mm. For low viscosity products and basic applications such as keeping products homogeneous, this mixer can handle volumes of up to 40 cubic meters.
Magnetic Mixing Applications
Magnetic mixing finds extensive applications across a multitude of industries, thanks to its versatility and efficiency. Some of the most common applications include:
- Low viscosity products
- Settling/separation
- Vaccines
- Antibiotics
- Injectables
Advantages
In comparison to other turbine-type mixers, the LeviMag offers some unique features:
- Levitated Design. The levitated impeller makes this mixer fully drainable and minimizes wear. It also provides greater process flexibility to handle a wide range of fluid types and mixing duties, ranging from high intensity mixing to the careful blending of product ingredients.
- Replaceable Bearings. Both the female and the male bearings can be replaced by the end-user on-site.
- High-Efficiency Impeller. Designed for low-shear mixing, the impeller unit provides for gentle treatment of the product being mixed.
- Mixing to the Last Drop. The four-wing, levitated design of the LeviMag's impeller and the mixer's dry-running capabilities combine to achieve maximum product yields.
- No tank penetrations, shafts, or seals. The weld plate becomes an integral part of the tank wall assuring complete containment and zero risk of contamination.
- Product flow from this mixer is optimized for the greatest efficiency and the lowest energy consumption.
- The open design, low-speed rotation, and full drainability optimizes cleaning-in-place, contributing to effective residue removal and minimal contamination from wear particles.
- Designed with ease of maintenance in mind. This mixer experiences minimal downtime in normal production operations, and the LeviMag does not require spare impellers. Tools for ready servicing are also available.
Depending on duty and media properties, the LeviMag is configurable for use in tanks ranging in volume from 30 liters to 40,000 liters. Two different model types of this magnetic mixer with five impeller diameters are available.
Each of the two LeviMag models can tailor the mixer's configuration to meet specific customer needs.
Also, several different drive unit configurations are available, including an epoxy-painted, TEFC (fan-cooled) version and another with a cleanroom finish with a sealed conversion treatment (smooth and closed, with no fan ventilation). An extended console may also be specified for use in insulated tanks.
Disadvantages
In comparison to directly-coupled turbine mixers, where the turbine rotor is directly attached to the motor via a rotating shaft, magnetic turbine mixers really only come with a few disadvantages, but these should be considered when considering this type of mixer.
- Complexity - In comparison to directly-coupled designs, magnetic turbine mixers are more complex in design, and the magnetic assembly between the motor and the turbine wheel is an additional part that can wear out over time.
- Mixing torque - Perhaps more significantly, magnetic turbine mixers do not provide the torque at the turbine wheel that is available to a directly-coupled turbine mixer, so the mixing wheel can slip when required to mix certain highly viscous liquid products. For this reason, magnetic turbine mixers are best used for mixing and combining low-viscosity, <1000 Cp, fluids and dry ingredients.
- Volume of materials to be mixed - Finally, because smaller turbine wheels are easier to spin magnetically than larger turbines, the mixing impeller in these types of mixers tend to be smaller in size in comparison to directly-coupled designs. As a result, magnetic turbine mixers are generally most efficient in mixing and stirring relatively smaller volumes of materials in a tank or vessel. In the case of the LeviMag, volumes of up to 10,500 gallons (40,000 liters) are capable of being mixed. Maximum mixable volume will vary by application.
Next Steps
Alfa Laval’s LeviMag magnetic mixers feature unique and patented technologies that provide optimal mixing of liquid products in tanks and vessels. While these mixers are primarily used for sanitary mixing applications in the pharmaceutical and biotechnology industries, they are also ideal for meeting the hygienic and aseptic processing needs in the food, beverage, and dairy industries.
Contact CSI at (417) 831-1411 to learn more about the LeviMag line of industrial mixers.
ABOUT CSI
Central States Industrial Equipment (CSI) is a leader in distribution of hygienic pipe, valves, fittings, pumps, heat exchangers, and MRO supplies for hygienic industrial processors, with four distribution facilities across the U.S. CSI also provides detail design and execution for hygienic process systems in the food, dairy, beverage, pharmaceutical, biotechnology, and personal care industries. Specializing in process piping, system start-ups, and cleaning systems, CSI leverages technology, intellectual property, and industry expertise to deliver solutions to processing problems. More information can be found at www.csidesigns.com.