1. What is a mixer and why mixing is required?
Mixers combine two or more materials uniformly to ensure homogeneity and consistent quality.
Mixing improves reaction rates, solubility and final product uniformity. It is essential in pharmaceuticals for dosage accuracy, blend uniformity and proper distribution of active ingredients.
2. Explain the principle of mixing.
Mixing works on bulk movement, diffusion and shear forces where particles or liquids move relative to each other to achieve uniform distribution.
It is achieved through rotation, agitation, tumbling or high shear, ensuring consistent dispersion of all components.
3. What are the types of mixers used in pharma/chemical plants?
Solid–solid mixers include V-blenders, double cone blenders and ribbon blenders. Liquid–liquid mixers include propeller, turbine and paddle mixers.
Liquid–solid mixers include high-shear mixers and planetary mixers, while specialized equipment includes sigma mixers, inline mixers and static mixers.
4. What is the difference between solid–solid, liquid–liquid and liquid–solid mixing?
Solid–solid mixing distributes particles uniformly using tumbling or convection. Liquid–liquid mixing achieves blending, emulsification or homogenization through agitation.
Liquid–solid mixing disperses powders into liquids using high shear to break agglomerates and achieve smooth dispersion.
5. Explain working of a ribbon blender.
A ribbon blender uses inner and outer helical ribbons rotating in opposite directions to create axial and radial powder movement.
This motion produces thorough, uniform mixing with low shear, making it suitable for dry powders, granules and fragile materials.
6. What is a double-cone blender?
A double-cone blender consists of two conical shells rotating around a horizontal axis, creating a gentle tumbling action.
It offers uniform mixing with minimal particle breakage and low heat generation, making it ideal for free-flowing powders and sensitive APIs.
7. What is a planetary mixer and where is it used?
A planetary mixer has blades that rotate on their own axis while simultaneously orbiting around the bowl, producing intense mixing and kneading.
It is used for viscous materials, creams, gels and pastes and ensures uniform shear throughout the batch.
8. What is a sigma mixer?
A sigma mixer uses two sigma-shaped blades rotating in opposite directions to generate strong shear, making it suitable for sticky, viscous or dough-like materials.
It is commonly used for resins, adhesives, rubber compounds and heavy pastes, ensuring uniform mixing in high-viscosity systems.
9. What is a V-blender and its applications?
A V-blender consists of two V-shaped cylinders that rotate to create a tumbling motion, resulting in uniform mixing of free-flowing powders.
It is widely used for APIs, excipients and sensitive materials and provides gentle blending with minimal heat buildup.
10. What are the advantages of a V-blender?
A V-blender offers uniform mixing with very low shear and is easy to clean, operate and maintain. It minimizes powder degradation and segregation while delivering efficient mixing with low power consumption, making it ideal for pharmaceutical blending.
11. What is tumbling mixing?
Tumbling mixing relies on the rotation of a container, causing materials to fall, roll and cascade over each other.
This gentle mixing method is ideal for free-flowing powders and blends that require minimal shear.
It offers uniform distribution when the blender shape and rotation speed are properly designed.
12. What is convective mixing?
Convective mixing involves bulk movement of large portions of material from one location to another.
It significantly reduces mixing time and is common in ribbon blenders, paddle mixers and plough shear mixers.
This method achieves rapid homogeneity, especially for powders with different densities.
13. What is shear mixing?
Shear mixing occurs when layers of material move relative to each other, generating friction and breaking agglomerates.
It is used for viscous materials, pastes and cohesive powders.
High-shear mixers, sigma mixers and rotor–stator mixers use this principle to achieve uniform dispersion.
14. Explain the working of a high-shear mixer.
A high-shear mixer uses an impeller to create strong mechanical agitation while a chopper breaks lumps and promotes granule formation.
The rapid movement generates intense shear forces that blend powders, add granulating liquid and create uniform wet mass.
It is widely used for wet granulation in pharmaceuticals.
15. What is granulation and how does a high-shear mixer help?
Granulation converts fine powders into larger, uniform granules to improve flowability and compressibility.
A high-shear mixer accelerates this process by combining rapid mixing, shear action and controlled liquid addition.
It ensures uniform granule size and consistent tablet quality.
16. What is an impeller?
An impeller is the primary mixing element that rotates to move material within a mixer.
Its shape determines the flow pattern and mixing intensity.
Impellers can generate axial or radial flow and are designed based on viscosity, product type and required shear.
17. What is a chopper in a high-shear mixer?
A chopper is a high-speed cutting blade used to break lumps and control granule size during mixing.
It enhances shear intensity and prevents the formation of oversized agglomerates.
The chopper works together with the impeller to produce consistent and uniform granules.
18. What factors affect mixing efficiency?
Mixing efficiency depends on mixer type, batch size, mixing speed, material flow properties, particle size distribution and moisture content.
Other important factors include impeller design, residence time and loading pattern.
Proper control of these ensures uniform blend quality.
19. What is mixing time?
Mixing time is the duration required to achieve uniform distribution of all components.
It depends on material properties, mixer design and operating parameters.
Optimal mixing time ensures homogeneity without overmixing, which can cause particle degradation or segregation.
20. What is bulk density and its role in mixing?
Bulk density is the mass of powder per unit volume, including void spaces.
It influences mixer loading capacity, flow behavior and blending uniformity.
Powders with different bulk densities may segregate easily, so understanding bulk density is essential for selecting the right mixer and mixing method.
21. What is angle of repose and why is it important for mixers?
Angle of repose is the maximum angle at which a pile of powder remains stable without sliding. It indicates powder flowability.
Powders with a low angle of repose flow easily and mix well, while high-angle powders may form dead zones or segregate, influencing mixer selection and performance.
22. Explain dead zones in mixing.
Dead zones are areas inside the mixer where material movement is minimal or stagnant.
They lead to poor mixing uniformity and inconsistent product quality.
Dead zones occur due to improper mixer design, low speed or uneven loading, and must be eliminated through baffles, correct impeller design or optimized speed.
23. What is segregation in mixing?
Segregation is the separation of mixed components due to differences in particle size, density or shape.
It often occurs after mixing during discharge, handling or storage.
Segregation results in non-uniform blends and must be minimized through proper mixer design, controlled material flow and optimized blend time.
24. How to prevent segregation during mixing?
Segregation can be prevented by using consistent particle size, controlling feed sequence, optimizing blender speed and avoiding overmixing.
Equipment such as V-blenders or double-cone blenders helps reduce segregation.
Proper discharge techniques and minimal handling also maintain blend uniformity.
25. What is Froude number and its significance in mixers?
Froude number (Fr) is used to analyze mixing behavior in rotating mixers. It is calculated as
Fr = (N² × D) / g
where N is rotation speed, D is mixer diameter and g is gravitational force.
It indicates whether mixing occurs by cascading, cataracting or centrifuging, and helps optimize speed settings.
26. What is tip speed in agitators?
Tip speed is the linear speed of the outermost point of an impeller blade. It is calculated as
Tip Speed = π × D × N
where D is impeller diameter and N is rotational speed.
Tip speed determines shear intensity and is crucial for dispersing powders and breaking agglomerates.
27. What types of blades are used in agitators?
Common blades include propeller blades for axial flow, turbine blades for radial flow and paddle blades for gentle mixing.
Anchor blades are used for viscous materials, while saw-tooth blades are used in dispersers for high-shear applications.
Blade selection depends on viscosity and mixing objective.
28. Explain axial flow vs radial flow impellers.
Axial flow impellers push material parallel to the shaft, providing top-to-bottom circulation ideal for blending and solid suspension.
Radial flow impellers push material outward and perpendicular to the shaft, creating strong shear suitable for gas dispersion and emulsification. Selection depends on process needs.
29. What is a propeller mixer?
A propeller mixer uses three-blade or multi-blade propellers to generate high axial flow.
It is suitable for low-viscosity liquids requiring fast blending, dissolution or solid suspension. Propeller mixers are widely used in reactors, tanks and formulation processes.
30. What is a turbine mixer?
A turbine mixer uses flat or curved blades mounted on a central hub to create strong radial flow.
It provides higher shear than a propeller mixer and is suitable for medium-viscosity liquids, emulsification, gas-liquid mixing and dispersion processes.
31. What is a baffle and why is it used in mixing tanks?
A baffle is a vertical plate installed inside a mixing tank to prevent swirling and vortex formation.
It improves top-to-bottom circulation, increases mixing efficiency and enhances turbulence.
Baffles are essential in liquid mixing to achieve uniform blending and proper mass transfer.
32. What causes vortex formation and how to prevent it?
Vortex forms when liquid rotates around the impeller shaft instead of mixing.
It is caused by high speed, low viscosity or lack of baffles. Preventing vortex requires installing baffles, reducing speed, adjusting impeller height or increasing liquid level to create proper mixing flow.
33. What is power number in mixing?
Power number (Np) is a dimensionless parameter indicating energy consumption by an impeller.
It depends on impeller design, flow pattern and Reynolds number. Np is used to estimate mixing power, scale up mixing systems and compare impeller performance across different mixers.
34. What is power consumption in agitators?
Power consumption is the energy used by an agitator to achieve mixing.
It depends on impeller size, speed, fluid viscosity and tank geometry.
Proper power calculation ensures adequate mixing without overloading the motor or causing excessive shear.
35. What is homogenization?
Homogenization is the process of breaking down particles or droplets into smaller, uniform sizes to create a stable mixture.
It is commonly used for emulsions, suspensions and creams. Rotor–stator mixers and high-pressure homogenizers are typically used for this purpose.
36. Difference between mixing and blending.
Mixing refers to the uniform distribution of two or more components in any physical state. Blending is a type of mixing usually involving dry powders or free-flowing solids.
Mixing often involves shear, while blending mainly relies on gentle tumbling or convection.
37. What are critical parameters for powder mixing?
Critical parameters include particle size, shape, density, moisture content, blender speed, fill level and mixing time.
Uniformity depends on free-flowing behavior and proper selection of mixer type to match powder characteristics.
38. What is mixing uniformity?
Mixing uniformity indicates how evenly components are distributed throughout the batch.
It is evaluated using sample analysis and RSD values. High mixing uniformity ensures dosage accuracy, product consistency and compliance with GMP.
39. How to validate mixing in pharma?
Validation involves defining critical process parameters, selecting sampling points, performing blend uniformity testing and calculating RSD.
Reproducibility of mixing results must be demonstrated across multiple batches to meet regulatory and GMP requirements.
40. What is RSD (Relative Standard Deviation) in mixing?
RSD measures the variation in sample concentrations and indicates blend uniformity. It is calculated as
RSD (%) = (Standard Deviation / Mean) × 100
A lower RSD value indicates better mixing uniformity and consistent product quality.
41. Why is sampling important after mixing?
Sampling after mixing verifies whether the blend has achieved the required uniformity. It helps detect segregation, dead zones or insufficient mixing.
Representative samples confirm consistency before compression, granulation or further processing, ensuring the batch meets GMP quality standards.
42. What is scale-up in mixing?
Scale-up involves transferring mixing parameters from laboratory or pilot scale to production scale.
It requires maintaining geometric similarity, flow patterns, power per volume and impeller speed ratios. Proper scale-up ensures product quality remains consistent across all batch sizes.
43. What is heat generation during mixing?
Heat is generated due to friction between particles or between viscous materials and impeller surfaces.
Excess heat may affect temperature-sensitive ingredients, cause degradation or affect viscosity. Controlling speed, using jacketed vessels and optimizing impeller design helps manage heat buildup.
44. Why are jacketed mixers used?
Jacketed mixers allow heating or cooling of the mixing vessel using circulating fluids such as steam, hot water or chilled water.
They control product temperature, improve solubility, maintain viscosity and protect temperature-sensitive formulations during mixing.
45. What is a vacuum mixer dryer?
A vacuum mixer dryer combines mixing and drying under reduced pressure.
Vacuum lowers the boiling point, enabling low-temperature drying of sensitive materials.
The mixer ensures uniform heat distribution and prevents lump formation while drying solids, powders or pastes efficiently.
46. What is a planetary gear mixer?
A planetary gear mixer uses a heavy-duty planetary gear system to rotate mixing arms around their axis while orbiting the bowl.
It provides strong shear and thorough mixing, ideal for viscous masses, adhesives, creams, gels and semi-solid formulations.
47. What is a disperser mixer and where is it used?
A disperser mixer uses a high-speed saw-tooth blade to disperse solids into liquids by generating intense shear.
It is used for paints, coatings, pigments, adhesives and formulations requiring fine particle dispersion or pigment wetting.
48. What are inline mixers?
Inline mixers perform mixing while the material flows through a pipeline.
They use rotor–stator systems or static elements to blend products continuously.
Inline mixers offer efficient emulsification, dispersion and homogenization without the need for large batch vessels.
49. Explain static mixers.
Static mixers contain fixed internal elements that split, rotate and recombine fluid streams as they pass through the pipe.
They require no moving parts and provide excellent mixing in continuous systems. Static mixers are ideal for blending liquids, gases and additives.
50. What is emulsification?
Emulsification is the process of mixing two immiscible liquids, usually oil and water, to form a stable emulsion.
High-shear mixers, rotor–stator systems and homogenizers create small droplets for stable emulsions used in creams, lotions, food products and chemical formulations.
51. What is a colloid mill?
A colloid mill is a high-shear mixer that reduces particle and droplet size by forcing material through a narrow gap between a rotor and stator.
It produces fine emulsions and dispersions and is widely used for creams, ointments, suspensions and food products.
52. What is a rotor–stator mixer?
A rotor–stator mixer uses a rapidly rotating rotor inside a stationary stator to create intense shear.
Material is drawn into the rotor–stator gap and broken into fine particles or droplets. It is used for emulsification, dispersion and homogenization in liquid systems.
53. What causes lumps formation during mixing?
Lumps form when moisture content is uneven, powders agglomerate or liquid is added too quickly.
Poor impeller action, improper sequencing or high humidity can also contribute.
Controlling liquid addition rate and using high-shear elements helps prevent lump formation.
54. How to avoid dusting during powder mixing?
Dusting can be avoided by using enclosed mixers, controlled powder charging, proper ventilation and slow initial mixing speeds.
Pre-wetting or granulation can also reduce dust. Maintaining proper humidity helps minimize airborne particles.
55. What are GMP requirements for mixers?
Mixers must be easily cleanable, constructed of non-reactive materials like stainless steel, and properly validated.
They require documented SOPs, calibration, maintenance, and cleaning records. Design must prevent contamination, dead zones and material buildup.
56. What cleaning methods are used for mixers?
Cleaning methods include dry brushing, vacuum cleaning, manual washing, pressure washing and cleaning with detergents.
For liquid systems, flushing and solvent rinsing are common. The method depends on product type, cross-contamination risk and equipment design.
57. What is CIP/SIP in mixers?
CIP (Clean-In-Place) cleans internal surfaces automatically without disassembly using circulating detergents.
SIP (Sterilize-In-Place) uses steam or hot water to sterilize equipment after cleaning. These systems ensure hygiene, reduce manual effort and improve GMP compliance.
58. What is batch vs continuous mixing?
Batch mixing processes a fixed quantity at a time and offers flexibility and control.
Continuous mixing allows uninterrupted material flow and is suitable for large-scale production.
Batch is common in pharma, while continuous is preferred in chemicals and food processing.
59. What is mixing intensity?
Mixing intensity refers to the amount of energy imparted to the material per unit volume.
Higher intensity improves dispersion and homogenization but may cause particle breakage or excessive heat.
It is controlled by speed, impeller design and power input.
60. What safety precautions are required for mixers?
Safety precautions include ensuring proper earthing, using interlocks, maintaining guards, checking seals, avoiding overloading and preventing access during operation.
Operators must follow PPE requirements and lockout–tagout procedures to prevent accidents.
61. What are discharge valve types used in mixers?
Discharge valves include butterfly valves, slide-gate valves, ball valves and flush-bottom valves.
The choice depends on powder flowability, cleanliness requirements and risk of material bridging.
Proper valve selection ensures smooth discharge and prevents segregation at the outlet.
62. What causes poor mixing uniformity?
Poor uniformity results from inadequate mixing time, incorrect fill level, low impeller speed, dead zones or material segregation.
Differences in particle size, density or moisture also contribute. Correcting mixer loading, speed and sampling strategy improves uniformity.
63. What is the purpose of spray nozzles in granulation mixers?
Spray nozzles deliver granulating liquid in controlled fine droplets to ensure even wetting of powder.
This prevents over-wetting, reduces lump formation and promotes uniform granule size. Proper nozzle angle and pressure are essential for consistent granulation.
64. What is torque and why relevant to mixers?
Torque is the rotational force required to turn the mixer shaft. It reflects material resistance and mixing load.
High torque indicates viscous or dense materials, helping monitor batch condition and detect abnormalities such as overloading or improper consistency.
65. What is viscosity and its effect on mixing?
Viscosity is a fluid’s resistance to flow. High-viscosity materials require stronger impellers, higher torque and slower speeds, while low-viscosity liquids mix easily with axial flow impellers. Viscosity directly influences mixer power, flow pattern and shear requirements.
66. How to choose the right mixer for a process?
Mixer selection depends on material type, viscosity, particle size, required shear, batch size and desired mixing outcome.
Process goals such as dispersion, blending, emulsification or granulation guide the choice. Equipment capability, safety and CIP needs are also considered.
67. Why mixing speed is controlled?
Speed affects shear, flow pattern, heat generation and mixing uniformity.
Too high speed may cause vortexing, segregation or particle damage, while too low speed may result in poor blending.
Controlled speed ensures efficient mixing without compromising product quality.
68. What is turbulence in mixing?
Turbulence refers to chaotic fluid motion that enhances mass transfer and mixing rate.
It is required for effective dispersion and emulsification.
Turbulence increases with high impeller speed, low viscosity and proper tank geometry.
69. What is laminar vs turbulent mixing?
Laminar mixing occurs in viscous materials where flow layers move smoothly without crossing.
Turbulent mixing involves chaotic flow with significant intermingling.
Laminar flow requires strong shear for effective mixing, while turbulent flow efficiently disperses particles.
70. What is power draw curve?
A power draw curve represents the relationship between agitator power consumption and operating conditions such as speed, viscosity and impeller type.
It helps determine optimal operating range, predict energy usage and identify abnormal conditions like excessive load.
71. What is mixing Reynolds number?
Mixing Reynolds number indicates the flow regime in a mixing system.
It is calculated based on fluid density, impeller speed, impeller diameter and viscosity.
Low Reynolds number represents laminar flow, while high values indicate turbulent mixing.
It helps determine the required mixing power and impeller type.
72. What are applications of high-speed dispersers?
High-speed dispersers are used for breaking agglomerates, dispersing pigments, wetting powders and preparing paints, inks, adhesives and coatings.
They generate intense shear using a saw-tooth blade and are ideal for low- to medium-viscosity formulations requiring fine particle dispersion.
73. What is wet mixing vs dry mixing?
Wet mixing involves combining powders with liquids to form a uniform wet mass, commonly used in granulation.
Dry mixing blends powders without any liquid addition and is used for API–excipient blending. Wet mixing creates stronger bonds between particles, while dry mixing relies on particle flow properties.
74. What is batch size optimization in mixing?
Batch size optimization ensures the mixer is filled within the recommended volume, typically 30–70% for blenders and 70–90% for liquid mixers.
Proper loading prevents dead zones, improves mixing efficiency and reduces mixing time while maintaining product quality.
75. What causes overheating in mixers?
Overheating occurs due to high impeller speed, excessive friction, high-viscosity materials or long mixing time.
It can degrade heat-sensitive materials or change viscosity. Reducing speed, using cooling jackets and optimizing mixing parameters prevents overheating.
76. What is mixer shaft alignment?
Mixer shaft alignment ensures the shaft runs precisely along its intended axis without wobbling.
Proper alignment reduces vibration, noise, bearing wear and mechanical failure. Misalignment can affect mixing efficiency and lead to breakdowns.
77. What is the role of seals and bearings in mixers?
Seals prevent leakage of materials around the shaft, especially in liquid mixing. Bearings support the rotating shaft and ensure smooth movement.
Both components are essential for reliable operation, reduced downtime and maintaining hygiene in pharmaceutical systems.
78. What is temperature control in mixers?
Temperature control maintains product temperature within acceptable limits using heating or cooling jackets.
It is critical for viscosity control, reaction kinetics and protecting heat-sensitive ingredients. Stable temperature ensures consistent product quality.
79. What are common mixer failures?
Common failures include seal leakage, bearing wear, motor overload, blade damage and shaft misalignment.
These issues are caused by improper maintenance, overloading, high viscosity or incorrect operating speed. Regular inspections and preventive maintenance reduce failures.
80. Why interlocks are required in mixers?
Interlocks prevent unsafe operation by disabling mixing when covers are open, speed limits are exceeded or overload occurs.
They protect operators, equipment and product quality.
Interlocks are essential for compliance with safety and GMP standards.
81. What tests are done during mixer qualification?
Mixer qualification includes installation checks, rotation direction verification, speed calibration, load tests and mixing performance trials.
Uniformity tests and sample analysis confirm the equipment consistently achieves the required blend quality.
82. What is noise/vibration analysis in mixers?
Noise and vibration analysis identifies mechanical issues such as misalignment, bearing wear or imbalance. Abnormal vibration indicates potential failures.
Monitoring ensures safe operation, protects equipment and maintains consistent mixing performance.
83. How to prevent cross-contamination in mixers?
Cross-contamination is prevented through proper cleaning, validated cleaning procedures, dedicated equipment, use of dust-tight systems and ensuring no residual product remains after discharge.
Compliance with GMP and proper material handling also play a key role.
84. What is particle breakage during mixing?
Particle breakage occurs when excessive shear or high-speed mixing fractures fragile particles.
It affects flowability, uniformity and final product quality. Controlling speed and selecting gentle mixers reduces breakage.
85. What is mixing pattern analysis?
Mixing pattern analysis studies how materials move inside the mixer, such as axial, radial or tangential flow.
It helps identify dead zones, improve impeller design and optimize mixing efficiency. Visualization and CFD tools are often used.
86. What is coating in powder mixing?
Coating refers to uniform deposition of one powder or liquid over another powder’s surface.
It is used in formulations to improve flow, stability or controlled release. Proper mixer selection ensures even coating without segregation.
87. Why sample thief is used?
A sample thief is used to collect samples from multiple depths and locations in a blender.
It helps assess blend uniformity and detect segregation or uneven mixing. Sampling ensures batch quality meets specifications.
88. What is mixing endpoint?
The mixing endpoint is the point at which the blend reaches required uniformity. It is determined by sampling, RSD analysis, torque monitoring or preset time.
Correct endpoint prevents under-mixing or over-mixing.
89. What is mass transfer in liquid mixing?
Mass transfer involves movement of molecules from one region to another during mixing. It is influenced by turbulence, shear and flow patterns.
Effective mass transfer is essential for dissolving solids, blending liquids and chemical reactions.
90. Why do baffles prevent swirling?
Baffles create flow resistance and interrupt circular motion of liquid.
This prevents swirling and vortex formation, ensuring proper top-to-bottom circulation. Baffles improve mixing energy efficiency and enhance shear and turbulence.
91. What are common challenges in large-scale mixing?
Large-scale mixing faces issues such as dead zones, slow blending, scale-up mismatches, inadequate shear and sampling difficulties. Proper impeller design, mixer geometry and process optimization help overcome these challenges.
92. What is the importance of residence time in continuous mixers?
Residence time determines how long material stays inside the mixer, affecting uniformity and throughput.
Insufficient residence time leads to poor mixing, while too long can cause over-processing. Controlled feed rate ensures consistent mixing quality.
93. Why is mixing uniformity testing required?
Uniformity testing ensures all components are evenly distributed and dosage accuracy is maintained.
It identifies segregation, sampling errors and variability. It is mandatory for GMP compliance, especially for pharmaceutical blends.
94. What is load factor for mixers?
Load factor refers to the proportion of mixer capacity that should be filled for optimal performance.
Underloading causes poor mixing, while overloading leads to dead zones. Each mixer type has recommended fill levels for best results.
95. What is vacuum deaeration during mixing?
Vacuum deaeration removes entrapped air or bubbles from liquids or pastes during mixing. It improves product density, appearance and stability.
Commonly used in creams, gels, adhesives and viscous formulations.
96. What is powder blending?
Powder blending is the process of combining dry powders to achieve a uniform mixture.
It relies on tumbling, convection or shear depending on powder properties.
Used extensively in pharma, chemicals, food and nutraceuticals.
97. Importance of pre-mixing.
Pre-mixing ensures coarse distribution of ingredients before final mixing.
It reduces mixing time, prevents segregation and ensures better granulation or emulsification later. Pre-mixing is critical for multi-step formulations.
98. What is wet granulation in mixers?
Wet granulation creates granules by adding binder liquid to powders under shear.
It improves compressibility, flowability and uniformity.
High-shear mixers and planetary mixers are commonly used for this process.
99. What causes agglomeration during mixing?
Agglomeration occurs due to moisture variation, excessive binder, electrostatic charge or high humidity.
Particles stick together forming lumps. Controlled liquid addition, proper drying and shear adjustment minimize agglomeration.
100. What is the difference between mixer and kneader?
A mixer blends powders or liquids to achieve uniformity, while a kneader handles highly viscous, dough-like materials using slow but strong shear.
Kneaders are used for adhesives, rubber and resins; mixers are used for powders, liquids and granules.