Industrial Mixing, Dosing and Process Equipment Glossary
Simple explanations of common terms used in agitators, dosing pumps, dosing systems, injection packages and inline mixing. Each definition also points to the related Premix product page for deeper reading.
Learn each industrial term in depth
A
Agitating Performance
Agitating performance describes how effectively an agitator achieves the required duty such as blending, suspension, dispersion, heat transfer or uniform chemical distribution.
Read: Agitating Performance Related: Industrial Agitator & MixerAgitator
Mechanical equipment used to mix, suspend, dissolve, disperse or homogenize fluids and slurries inside a tank or vessel.
Read: Agitator Related: Industrial Agitator & MixerAeration
Aeration is the introduction of gas into liquid during mixing, commonly for oxygen transfer, biological treatment or gas-liquid reaction.
Read: Aeration Related: Industrial Agitator & MixerApparent Viscosity
Apparent viscosity is the effective viscosity of a non-Newtonian fluid under a specific shear rate and temperature.
Read: Apparent Viscosity Related: Heavy Duty AgitatorsAxial Flow
Axial flow is a flow pattern where liquid moves parallel to the agitator shaft direction, creating up-and-down tank circulation.
Read: Axial Flow Related: Hydrofoil ImpellerAxial Thrust
Axial thrust is the vertical force generated by the impeller on the shaft, bearings and gearbox during operation.
Read: Axial Thrust Related: Industrial Agitator & MixerB
Baffle
Baffles are vertical plates mounted inside tank walls to prevent vortex formation, increase turbulence and improve mixing efficiency.
Read: Baffle Related: Industrial Agitator & MixerBatch Mixing
Batch mixing is the mixing of a fixed quantity of liquid, powder or slurry in one processing cycle.
Read: Batch Mixing Related: Top Entry AgitatorBlending Time
Blending time is the time required to achieve the desired homogeneity in a tank after addition of one or more components.
Read: Blending Time Related: Industrial Agitator & MixerBulk Velocity
Bulk velocity is the average large-scale circulation velocity inside a tank created by the agitator.
Vb approx N x D Read: Bulk Velocity Related: Top Entry AgitatorC
Cavern Formation
Cavern formation is a localized mixed zone around the impeller in highly viscous or yield-stress fluids while outer regions remain poorly mixed.
Read: Cavern Formation Related: Heavy Duty AgitatorsCFD
CFD, or Computational Fluid Dynamics, is a simulation method used to analyze flow pattern, turbulence, velocity profile and dead zones inside mixing equipment.
Read: CFD Related: Industrial Agitator & MixerChemical Dosing System
A chemical dosing system is a packaged arrangement of tank, agitator, dosing pump, valves, piping, instruments and controls used for safe chemical preparation and injection.
Read: Chemical Dosing System Related: Chemical Dosing SystemsChemical Injection Package
A chemical injection package is a skid-mounted system used to inject process chemicals such as corrosion inhibitor, antiscalant, methanol or additives.
Read: Chemical Injection Package Related: Additive Injection PackageCirculation Rate
Circulation rate is the volume of liquid pumped by the impeller per unit time.
Q = Nq x N x D^3 Read: Circulation Rate Related: Hydrofoil ImpellerCorrosion Inhibitor Injection
Corrosion inhibitor injection is controlled chemical dosing used to reduce corrosion risk in pipelines, process systems and utility circuits.
Read: Corrosion Inhibitor Injection Related: Dosing SystemsCritical Speed
Critical speed is the rotational speed where shaft natural frequency matches operating frequency, creating a vibration risk.
Read: Critical Speed Related: Industrial Agitator & MixerD
Dead Zone
A dead zone is a poorly mixed region inside a vessel where liquid movement is weak or stagnant.
Read: Dead Zone Related: Industrial Agitator & MixerDiaphragm Pump
A diaphragm dosing pump uses a reciprocating diaphragm to move chemical without direct contact between liquid and drive mechanism.
Read: Diaphragm Pump Related: Mechanical Diaphragm PumpDispersion
Dispersion is the process of breaking gas or liquid into fine bubbles or droplets inside another phase.
Read: Dispersion Related: High Speed AgitatorsDissolution
Dissolution is the process of dissolving solids into a liquid until the solid becomes part of the solution.
Read: Dissolution Related: Dosing SystemsDissolving System
A dissolving system prepares powder or granular chemical into a usable solution before dosing.
Read: Dissolving System Related: Polymer Dosing SystemDosing Pump
A dosing pump is a precision pump used to inject a measured amount of chemical into a process line, tank or treatment system at a controlled flow rate.
Read: Dosing Pump Related: Dosing PumpDrag Force
Drag force is the resistance force acting opposite to motion when a body, particle or impeller blade moves through fluid.
Read: Drag Force Related: Industrial Agitator & MixerE
Eddy
An eddy is a small turbulent swirling flow structure formed during mixing.
Read: Eddy Related: Industrial Agitator & MixerEffective Mixing Volume
Effective mixing volume is the actual volume inside a vessel that is properly mixed by the agitator.
Read: Effective Mixing Volume Related: Industrial Agitator & MixerEnergy Dissipation Rate
Energy dissipation rate is the energy lost into turbulence per unit mass of fluid.
Read: Energy Dissipation Rate Related: High Speed AgitatorsF
Flash Mixer
A flash mixer provides quick, high-intensity mixing so treatment chemicals can disperse rapidly into water or process liquid.
Read: Flash Mixer Related: Flash MixerFlocculant Dosing
Flocculant dosing introduces polymer or coagulant chemicals into water or wastewater to support particle agglomeration and separation.
Read: Flocculant Dosing Related: Dosing SystemsFlooding
Flooding is a gas-liquid mixing condition where gas flow overwhelms the impeller pumping capacity.
Read: Flooding Related: Industrial Agitator & MixerFlow Number
Flow number, Nq, is a dimensionless parameter representing the pumping capacity of an impeller.
Nq = Q / (N x D^3) Read: Flow Number Related: Hydrofoil ImpellerFroude Number
Froude number compares inertial force to gravity force and is important for surface vortex and high-speed mixing behavior.
Fr = N^2 x D / g Read: Froude Number Related: High Speed AgitatorsG
Gas Dispersion
Gas dispersion is the uniform distribution of gas bubbles into liquid using an agitator or mixer.
Read: Gas Dispersion Related: Industrial Agitator & MixerGearbox Service Factor
Gearbox service factor is a safety margin applied to gearbox torque selection for agitator duty.
Read: Gearbox Service Factor Related: Heavy Duty AgitatorsGel Phase Mixing
Gel phase mixing is mixing of highly viscous gel-like materials that may not flow easily at low shear.
Read: Gel Phase Mixing Related: Heavy Duty AgitatorsH
Heat Transfer Coefficient
Heat transfer coefficient measures heat transfer effectiveness during agitation between a liquid and vessel wall, coil or jacket.
Read: Heat Transfer Coefficient Related: Reactor AgitatorsHeavy Duty Agitator
A heavy duty agitator is designed for demanding mixing conditions such as high viscosity, large tanks, continuous operation, slurry suspension or high torque duties.
Read: Heavy Duty Agitator Related: Heavy Duty AgitatorsHomogenization
Homogenization is the uniform distribution of components so the mixture has consistent composition throughout the tank.
Read: Homogenization Related: Industrial Agitator & MixerHydraulic Diaphragm Pump
A hydraulic diaphragm dosing pump uses hydraulic actuation to move the diaphragm and is suitable for higher pressure chemical metering applications.
Read: Hydraulic Diaphragm Pump Related: Hydraulic Diaphragm PumpHydrofoil Impeller
A hydrofoil impeller is a high-efficiency axial-flow impeller that gives high pumping capacity with low shear and lower power draw.
Read: Hydrofoil Impeller Related: Hydrofoil ImpellerI
Impeller
An impeller is the rotating mixing element attached to an agitator shaft.
Read: Impeller Related: Agitator ImpellersImpeller Diameter Ratio
Impeller diameter ratio is the ratio of impeller diameter to tank diameter.
D/T Read: Impeller Diameter Ratio Related: Agitator ImpellersImpeller Tip Speed
Impeller tip speed is the linear speed at the outer edge of the impeller.
Vtip = pi x D x N Read: Impeller Tip Speed Related: Agitator ImpellersInjection Quill
An injection quill introduces chemical into the center of a pipeline or process stream, improving dispersion and reducing chemical attack near the pipe wall.
Read: Injection Quill Related: Chemical Injection SystemsInline Mixer
An inline mixer blends fluids inside a pipeline. Static mixers are a common inline mixer type using fixed elements instead of a rotating shaft.
Read: Inline Mixer Related: Static MixerJ
Just Suspension Speed
Just suspension speed, Njs, is the minimum agitator speed required to keep all solids suspended from the vessel bottom.
Read: Just Suspension Speed Related: Heavy Duty AgitatorsK
Kinematic Viscosity
Kinematic viscosity is the ratio of dynamic viscosity to fluid density.
nu = mu / rho Read: Kinematic Viscosity Related: Industrial Agitator & MixerL
Laminar Flow
Laminar flow is a smooth flow regime at low Reynolds number where viscous forces dominate.
Re < 10 Read: Laminar Flow Related: Heavy Duty AgitatorsLiquid Level
Liquid level is the operating liquid height inside a vessel or tank.
Read: Liquid Level Related: Industrial Agitator & MixerM
Mass Transfer
Mass transfer is the movement of material between phases, such as gas into liquid during oxygen transfer.
Read: Mass Transfer Related: Industrial Agitator & MixerMechanical Seal
A mechanical seal is a leak-control sealing system between a rotating shaft and a tank or vessel.
Read: Mechanical Seal Related: Reactor AgitatorsMetering Pump
A metering pump delivers controlled chemical flow with repeatable accuracy.
Read: Metering Pump Related: Metering PumpMixing Intensity
Mixing intensity is the relative mixing strength produced by RPM, power input and impeller type.
Read: Mixing Intensity Related: Industrial Agitator & MixerMixing Tank
A mixing tank is a vessel used with an agitator or mixer to blend, dissolve, prepare, suspend or condition liquids and chemicals before use.
Read: Mixing Tank Related: Industrial MixersMixing Time
Mixing time is the time needed to achieve concentration uniformity in a vessel.
Read: Mixing Time Related: Industrial Agitator & MixerN
Newtonian Fluid
A Newtonian fluid has constant viscosity regardless of shear rate.
Read: Newtonian Fluid Related: Industrial Agitator & MixerNon-Newtonian Fluid
A non-Newtonian fluid has viscosity that changes with shear rate.
Read: Non-Newtonian Fluid Related: Heavy Duty AgitatorsNPSH
NPSH, or Net Positive Suction Head, indicates suction pressure margin to avoid pump cavitation.
Read: NPSH Related: Dosing PumpO
Off-Bottom Suspension
Off-bottom suspension is the condition where solids are fully lifted from the vessel bottom during agitation.
Read: Off-Bottom Suspension Related: Heavy Duty AgitatorsOverhung Load
Overhung load is the load acting on gearbox bearings due to shaft, coupling and impeller weight or side loading.
Read: Overhung Load Related: Industrial Agitator & MixerP
Paddle Impeller
A paddle impeller is a simple mixing element used for moderate speed blending, flow movement and duties where strong circulation is needed at lower shear.
Read: Paddle Impeller Related: Paddle ImpellerPBT
PBT, or pitched blade turbine, is a common impeller with mixed axial and radial flow, usually with four blades at 45 degrees.
Read: PBT Related: Turbine ImpellerpH Correction System
A pH correction system doses acid or alkali to bring water or process liquid into a desired pH range.
Read: pH Correction System Related: pH Correction SystemPlunger Pump
A plunger dosing pump uses a reciprocating plunger to meter liquid and is commonly selected for accurate dosing at higher pressure.
Read: Plunger Pump Related: Plunger PumpPolymer Degradation
Polymer degradation is the breaking of polymer chains due to excessive shear during mixing or pumping.
Read: Polymer Degradation Related: Polymer Dosing SystemPolymer Dosing System
A polymer dosing system prepares and injects polymer solution for water treatment, wastewater treatment, sludge handling and clarification applications.
Read: Polymer Dosing System Related: Polymer Dosing SystemPower Consumption
Power consumption is the power absorbed by an agitator during operation.
P = Np x rho x N^3 x D^5 Read: Power Consumption Related: Industrial Agitator & MixerPower Number
Power number, Np, is a dimensionless parameter representing impeller power characteristics.
Np = P / (rho x N^3 x D^5) Read: Power Number Related: Industrial Agitator & MixerPropeller Impeller
A propeller impeller provides axial flow and is used for general blending, circulation and mixing of low to medium viscosity liquids.
Read: Propeller Impeller Related: Propeller ImpellerPumping Capacity
Pumping capacity is the ability of an impeller to circulate fluid through the tank.
Q = Nq x N x D^3 Read: Pumping Capacity Related: Hydrofoil ImpellerQ
Quality of Mixing
Quality of mixing is the measure of how homogeneous the final mixture is after agitation.
Read: Quality of Mixing Related: Industrial Agitator & MixerR
Radial Flow
Radial flow is flow moving perpendicular to the agitator shaft, commonly produced by Rushton turbine impellers.
Read: Radial Flow Related: Rushton Turbine ImpellerReactor Agitator
A reactor agitator is designed for controlled mixing in reaction vessels where temperature, dispersion, mass transfer or process uniformity is important.
Read: Reactor Agitator Related: Reactor AgitatorsResidence Time
Residence time is the average time fluid stays inside a vessel or process system.
Read: Residence Time Related: Dosing SystemsReynolds Number
Reynolds number is the most important mixing regime parameter and compares inertial force with viscous force.
Re = rho x N x D^2 / mu Read: Reynolds Number Related: Industrial Agitator & MixerRushton Turbine
A Rushton turbine is a radial-flow impeller used for gas dispersion, high shear mixing and applications requiring strong turbulence.
Read: Rushton Turbine Related: Rushton Turbine ImpellerS
Settling Velocity
Settling velocity is the speed at which particles settle due to gravity in a liquid.
Read: Settling Velocity Related: Heavy Duty AgitatorsShaft Runout
Shaft runout is the deviation of a shaft from its true rotational centerline.
Read: Shaft Runout Related: Industrial Agitator & MixerShear Rate
Shear rate is the velocity gradient in a fluid and indicates how strongly layers of fluid move relative to each other.
Read: Shear Rate Related: High Speed AgitatorsSide Entry Agitator
A side entry agitator is mounted on the side wall of a tank and is often used for storage tanks and large vessels.
Read: Side Entry Agitator Related: Side Entry AgitatorSkid-Mounted System
A skid-mounted system is preassembled on a structural base with equipment, piping and controls.
Read: Skid-Mounted System Related: Integrated Chemical Dosing SystemSolid Suspension
Solid suspension is the mixing duty of keeping solids uniformly suspended in liquid.
Read: Solid Suspension Related: Heavy Duty AgitatorsSpecific Power
Specific power is the agitator power per unit volume of liquid.
Specific Power = P / V Read: Specific Power Related: Industrial Agitator & MixerStatic Mixer
A static mixer blends liquids through fixed internal elements installed inside a pipe without a rotating drive.
Read: Static Mixer Related: Static MixerSurface Vortex
A surface vortex is a whirlpool formation on the liquid surface, usually undesirable in mixing.
Read: Surface Vortex Related: Industrial Agitator & MixerT
Tip Speed
Tip speed is the peripheral speed of the impeller at the outer edge.
Vtip = pi x D x N Read: Tip Speed Related: Agitator ImpellersTop Entry Agitator
A top entry agitator is installed from the top of a tank or vessel and is commonly used for blending, dissolution, suspension and dispersion.
Read: Top Entry Agitator Related: Top Entry AgitatorTorque
Torque is the rotational twisting force required to turn the agitator shaft and impeller.
T = P / (2 x pi x N) Read: Torque Related: Heavy Duty AgitatorsTransitional Flow
Transitional flow is the intermediate mixing regime between laminar and turbulent flow.
10 < Re < 10000 Read: Transitional Flow Related: Industrial Agitator & MixerTurbine Impeller
A turbine impeller is used where higher turbulence, dispersion or radial flow is required in an industrial mixing process.
Read: Turbine Impeller Related: Turbine ImpellerTurbulent Flow
Turbulent flow is a highly chaotic mixing regime where inertial forces dominate viscous forces.
Re > 10000 Read: Turbulent Flow Related: Industrial Agitator & MixerU
Uniformity Index
Uniformity index indicates the quality of mixing homogeneity inside a vessel.
Read: Uniformity Index Related: Industrial Agitator & MixerV
Viscosity
Viscosity is the resistance of a fluid to flow.
Read: Viscosity Related: Industrial Agitator & MixerVortex
A vortex is a rotating liquid depression formed at the liquid surface during agitation, usually undesirable.
Read: Vortex Related: Industrial Agitator & MixerW
Wetted Parts
Wetted parts are equipment components directly exposed to the process fluid or chemical.
Read: Wetted Parts Related: Dosing PumpWetting
Wetting is the process of liquid contacting and penetrating the surface of a solid particle.
Read: Wetting Related: Polymer Dosing SystemY
Yield Stress
Yield stress is the minimum stress needed before a material begins to flow.
Read: Yield Stress Related: Heavy Duty AgitatorsZ
Zwietering Correlation
Zwietering correlation is an empirical equation used to estimate just suspension speed, Njs, for solid suspension duties.
Read: Zwietering Correlation Related: Heavy Duty AgitatorsA
Agitator
An agitator is a rotating mixing device installed in a tank or vessel to move liquid, suspend solids, blend ingredients, improve heat transfer or maintain uniform process conditions.
Related: Industrial Agitator & MixerAnchor Agitator
An anchor agitator uses a close-clearance anchor type impeller for viscous liquids, heat transfer duties and applications where material may otherwise settle or stick near vessel walls.
Related: Anchor ImpellerAxial Flow
Axial flow describes liquid movement parallel to the agitator shaft. It is useful for bulk circulation, blending and solid suspension in many industrial tanks.
Related: Hydrofoil ImpellerAgitating Performance
Agitating performance describes how effectively an agitator achieves the process objective, such as blending, suspension, dispersion, heat transfer or uniform chemical distribution.
Read: Agitating PerformanceB
Bottom Entry Agitator
A bottom entry agitator is mounted from the bottom of a vessel. It is often used where top space is limited or where a compact mixing arrangement is preferred.
Related: Agitator RangeBulk Mixing
Bulk mixing is the overall circulation of liquid inside a tank so that concentration, temperature or suspended solids become uniform throughout the working volume.
Related: Top Entry AgitatorC
Chemical Dosing System
A chemical dosing system is a packaged arrangement of tank, agitator, dosing pump, valves, piping, instruments and controls used to prepare and inject chemicals safely and repeatably.
Related: Chemical Dosing SystemsChemical Injection Package
A chemical injection package is a skid-mounted system used to inject corrosion inhibitors, antiscalants, oxygen scavengers, methanol, additives or other process chemicals into a line or vessel.
Related: Additive Injection PackageCorrosion Inhibitor Injection
Corrosion inhibitor injection is controlled chemical dosing used to reduce corrosion risk in pipelines, process systems and utility circuits.
Related: Dosing SystemsD
Dosing Pump
A dosing pump is a precision pump used to inject a measured amount of chemical into a process line, tank or treatment system at a controlled flow rate.
Related: Dosing PumpDiaphragm Pump
A diaphragm dosing pump uses a reciprocating diaphragm to move chemical without direct contact between the liquid and drive mechanism.
Related: Mechanical Diaphragm PumpDissolving System
A dissolving system prepares powder or granular chemical into a usable solution before dosing. It is commonly used for polymer, lime and other treatment chemicals.
Related: Polymer Dosing SystemF
Flash Mixer
A flash mixer provides quick, high-intensity mixing so treatment chemicals can disperse rapidly into a water or process stream.
Related: Flash MixerFlocculant Dosing
Flocculant dosing introduces coagulant or polymer chemicals into water or wastewater to support particle agglomeration and separation.
Related: Dosing SystemsH
Heavy Duty Agitator
A heavy duty agitator is designed for demanding mixing conditions such as high viscosity, large tanks, continuous operation, slurry suspension or high torque duties.
Related: Heavy Duty AgitatorsHydraulic Diaphragm Pump
A hydraulic diaphragm dosing pump uses hydraulic actuation to move the diaphragm and is suitable for higher pressure chemical metering applications.
Related: Hydraulic Diaphragm PumpHydrofoil Impeller
A hydrofoil impeller is an efficient axial-flow impeller used for low power draw, strong circulation and gentle bulk mixing.
Related: Hydrofoil ImpellerI
Impeller
An impeller is the rotating blade or mixing element attached to an agitator shaft. Its shape controls flow pattern, shear level, pumping capacity and mixing result.
Related: Agitator ImpellersInjection Quill
An injection quill introduces chemical into the center of a pipeline or process stream, improving dispersion and reducing chemical attack near the pipe wall.
Related: Chemical Injection SystemsInline Mixer
An inline mixer blends fluids inside a pipeline. Static mixers are a common inline mixer type that use fixed elements instead of a rotating shaft.
Related: Static MixerM
Metering Pump
A metering pump delivers a controlled flow of chemical with repeatable accuracy. It is widely used for dosing acid, alkali, antiscalant, chlorine, polymer and process additives.
Related: Metering PumpMixing Tank
A mixing tank is a vessel used with an agitator or mixer to blend, dissolve, prepare, suspend or condition liquids and chemicals before use.
Related: Industrial MixersP
Paddle Impeller
A paddle impeller is a simple mixing element used for moderate speed blending, flow movement and duties where strong circulation is needed at lower shear.
Related: Paddle ImpellerpH Correction System
A pH correction system doses acid or alkali to bring water or process liquid into a desired pH range for treatment, process stability or discharge compliance.
Related: pH Correction SystemPlunger Pump
A plunger dosing pump uses a reciprocating plunger to meter liquid and is commonly selected for accurate dosing at higher pressure.
Related: Plunger PumpPolymer Dosing System
A polymer dosing system prepares and injects polymer solution for water treatment, wastewater treatment, sludge handling and clarification applications.
Related: Polymer Dosing SystemPropeller Impeller
A propeller impeller provides axial flow and is used for general blending, circulation and mixing of low to medium viscosity liquids.
Related: Propeller ImpellerR
Reactor Agitator
A reactor agitator is designed for controlled mixing in reaction vessels where temperature, dispersion, mass transfer or process uniformity is important.
Related: Reactor AgitatorsRushton Turbine
A Rushton turbine is a radial-flow impeller used for gas dispersion, high shear mixing and applications that require strong turbulence.
Related: Rushton Turbine ImpellerS
Side Entry Agitator
A side entry agitator is mounted on the side wall of a tank and is often used for storage tanks, large vessels and applications where top mounting is not practical.
Related: Side Entry AgitatorSkid-Mounted System
A skid-mounted system is preassembled on a structural base with equipment, piping and controls, reducing site installation work and improving service access.
Related: Integrated Chemical Dosing SystemStatic Mixer
A static mixer blends liquids through fixed internal elements installed inside a pipe. It has no rotating drive and is useful for continuous inline mixing.
Related: Static MixerSolid Suspension
Solid suspension is a mixing duty where settled particles are lifted and kept distributed in liquid by the agitator flow pattern.
Related: Heavy Duty AgitatorsT
Top Entry Agitator
A top entry agitator is installed from the top of a tank or vessel and is commonly used for blending, dissolution, suspension, dispersion and chemical process mixing.
Related: Top Entry AgitatorTurbine Impeller
A turbine impeller is used where higher turbulence, dispersion or radial flow is required in an industrial mixing process.
Related: Turbine Impeller