Solids Load RatioSolids loading ratioRatio of solids transported vs air transport 

Pneumatic
Transport
Types of pneumatic transport Conveying phases Dilute Phase transport Dense Phase transport Air mover Roots Blower After Cooler Airlock Rotary Valve Product inlet / Injector Piping Pickup
velocity
Conveying speed / velocity Air volumetric and mass flowrate Pipe Equivalent Length Solids velocity in pipe Bends Solids Breakage Pressure drop Pipe Diameter or Bore
Design methods
Pipe Blockage
Powder Buildup
Selecting dilute or dense
phase
Horizontal Conveying
Vertical Conveying

1. DefinitionThe solids load ratio is defined as the ratio of the mass of solids transported over the mass of air  or other gas  transporting the solids. Along with the air conveying velocity, the solids load ratio is very important parameter to characterize the flow of the solids in the conveying pipe and classify it as dilute phase, dense phase or intermediary. 2. CalculationThe solids loading ratio is calculated by divided the mass flowrate of solids by the mass flowrate of conveying air. Equation 1 : calculation of solids loading ratio With :  m_{air} = mass flowrate of transport air (kg/h) m_{material} = mass flowrate of conveyed material (kg/h) Note the following : the litterature is giving various formula for the solids load ratio to cope with different units. The equation above is the most simplest way to calculate the ratio, although you may have to make intermediary calculations to be able to determine the air mass rate. It is important to have both air mass flowrate and material mass flow rate in the same units. 3. Usual values for dilute and dense phase conveyingEvery conveying line is unique and will have its specific product air ratio, however, some orders of magnitudes can be given for both dilute and dense phase. Some of the ranges given overlap as at a same loading ratio in the intermediary zone some materials will behave in denser phase than others.
Table 1 : Reference solids
load ratio for dilute and dense phase conveying

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