Slurry

Examples

Examples of slurries include:

Cement slurry, a mixture of cement, water, and assorted dry and liquid additives used in the petroleum and other industries

Soil/cement slurry, also called Controlled Low-Strength Material (CLSM), flowable fill, controlled density fill, flowable mortar, plastic soil-cement, K-Krete, and other names

A mixture of thickening agent, oxidizers, and water used to form a gel explosive

A mixture of pyroclastic material, rocky debris, and water produced in a volcanic eruption and known as a lahar

A mixture of bentonite and water used to make slurry walls

Coal slurry, a mixture of coal waste and water, or crushed coal and water

Slurry oil, the highest boiling fraction distilled from the effluent of an FCC unit in a oil refinery. It contains large amount of catalyst, in form of sediments hence the denomination of slurry.

A mixture of wood pulp and water used to make paper

Manure slurry, a mixture of animal waste, organic matter, and sometimes water often known simply as "slurry" in agricultural use, used as fertilizer after ageing in a slurry pit

Meat slurry, a mixture of finely ground meat and water, centrifugally dewatered and used as food

An abrasive substance used in chemical-mechanical polishing

Slurry ice, a mixture of ice crystals, freezing point depressant, and water

A mixture of raw materials and water involved in the rawmill manufacture of Portland cement

A mixture of minerals, water, and additives used in the manufacture of ceramics

A bolus of chewed food mixed with saliva

Determining solids fraction

To determine the percent solids (or solids fraction) of a slurry from the density of the slurry, solids and liquid

ϕ s l = ρ s ( ρ s l − ρ l ) ρ s l ( ρ s − ρ l )

where

ϕ s l is the solids fraction of the slurry (state by mass) ρ s is the solids density ρ s l is the slurry density ρ l is the liquid density

In aqueous slurries, as is common in mineral processing, the specific gravity of the species is typically used, and since S G w a t e r is taken to be 1, this relation is typically written:

ϕ s l = ρ s ( ρ s l − 1 ) ρ s l ( ρ s − 1 )

even though specific gravity with units tonnes/m^3 (t/m^3) is used instead of the SI density unit, kg/m^3.

Liquid mass from mass fraction of solids

To determine the mass of liquid in a sample given the mass of solids and the mass fraction: By definition

ϕ s l = M s M s l *100

therefore

M s l = M s ϕ s l

and

M s + M l = M s ϕ s l

then

M l = M s ϕ s l − M s

and therefore

M l = 1 − ϕ s l ϕ s l M s

where

ϕ s l is the solids fraction of the slurry M s is the mass or mass flow of solids in the sample or stream M s l is the mass or mass flow of slurry in the sample or stream M l is the mass or mass flow of liquid in the sample or stream

Volumetric fraction from mass fraction

ϕ s l , m = M s M s l

Equivalently

ϕ s l , v = V s V s l

and in a minerals processing context where the specific gravity of the liquid (water) is taken to be one:

ϕ s l , v = M s S G s M s S G s + M l 1

So

ϕ s l , v = M s M s + M l S G s

and

ϕ s l , v = 1 1 + M l S G s M s

Then combining with the first equation:

ϕ s l , v = 1 1 + M l S G s ϕ s l , m M s M s M s + M l

So

ϕ s l , v = 1 1 + S G s ϕ s l , m M l M s + M l

Then since

ϕ s l , m = M s M s + M l = 1 − M l M s + M l

we conclude that

ϕ s l , v = 1 1 + S G s ( 1 ϕ s l , m − 1 )

where

ϕ s l , v is the solids fraction of the slurry on a volumetric basis ϕ s l , m is the solids fraction of the slurry on a mass basis M s is the mass or mass flow of solids in the sample or stream M s l is the mass or mass flow of slurry in the sample or stream M l is the mass or mass flow of liquid in the sample or stream komi S G s is the bulk specific gravity of the solids