Physical Properties of Oil & Gas Particulate Solids - Density (B-FSM-013)
Particulate solids have three types of density that can be measured – bulk, apparent, and true. Each type provides specific information for design of a Facilities Sand Management system.
Bulk Density
- The weight of the many particles divided by total volume
- Depends on particle apparent density, particle size distribution, and degree of compaction or settling
- Used to convert weight to volume of total solids handled and transported
- Measured with bulk container – easy to measure in the field
- Value dependent upon degree of compaction and fluid filling void space
- The photo below shows field measurement (estimate) of collected solids using a glass container
Apparent Density
- Density of individual particles inclusive of any closed pore space or cracks
- Also includes density of clusters or aggregates that act as single particle
- Measured with immersion pycnometer (Archimedes Principle)
- Used to calculate movement of actual particle through fluid and calculation of bulk density (packing) from concentration
- The photo below shows sand from a Texas oil well showing particle fractures
True Density
- Density of base material (mineral) making up individual particles
- The particles are ground/crushed to expose all particle pore space or cracks then measure with immersion pycnometer
- Used to compare mineralogy of particle
- Photo below shows immersion pycnometer measuring density of ground sand
All densities have the value of mass per unit volume. Common units are kg/m³, lb/ft³, or g/cm³. A comparison of densities for common minerals encountered in oil and gas industry are listed in the table below.
Bibliography
- Lowell, S., Shields, J.E., Thomas, M.A., Thommes, M. Characterization of Porous Solids and Powders: Surface Area, Pore Size and Density – Particle Technology Series Book 16. 2006.
