The Nature and Handling of Organic Slurries

Douglas W. Hamilton, Ph.D., P.E.Waste Management Specialist

Oklahoma Cooperative Extension Service

The Nature and Handling of Organic Slurries

Solids Speciation Suspensions Consistency Rheology Solids Settling Flow of Suspensions in Pipelines

Slurry: mixture of solids and liquids

What is a solid?

Remains after heating at 103o C

for 24 hoursSolid

Liquid

Sample

NO

Yes

What is a solid?

Remains after heating at 103o C

for 24 hoursSolid

Liquid

Sample

Mass of SolidsMass of Sample TS=

NO

Yes

Suspended or Dissolved ?

Passes through 1.5 Micron Diameter

Hole?Dissolved

Suspended

Sample

NO

Yes

Hamilton D.W. 2011. Solids Content of Wastewater and Manure. OSU Factsheet BAE-1759. Stillwater, OK:Oklahoma Cooperative Extension Service.

Parti

cle

Type

Sepa

ratio

n Pr

oces

s

Particle Size (micron)0.01 0.1 1.0 10.0 100 1,000

SandSiltClay

BacteriaViruses

Cysts

Algae

Asbestos Fibers

Screens

Fabric Filters

Settling

Centrifuge

Media Filter

Ultra Filter

Micro Filter

Suspended or Dissolved ?

Passes through 1.5 Micron Diameter

Hole?Dissolved

Suspended

Sample

NO

Yes

TS TDS

TSS

50

60

70

80

90

100

0 500 1,000 1,500 2,000 2,500 3,000 3,500

Seive Opening (microns)

% P

assi

ng

0

10

20

30

40

50

% R

etai

ned

Fine ground cornCracked CornWhole Kernel Corn

50

60

70

80

90

100

0 500 1,000 1,500 2,000 2,500 3,000 3,500

Seive Opening (microns)

% P

assi

ng

0

10

20

30

40

50

% R

etai

ned

Fine ground cornCracked CornWhole Kernel Corn

Hamilton D.W. 2008. Solids separation in manure handling systems. Factsheet 10-02-02h in Pork Industry Handbook. West Lafayette, IN:Purdue University

Distribution of Suspended Solids

Organic or Inorganic ?

Volatilizes when heated at 550oC

for 2 hours?

Volatile SolidOrganic

Fixed SolidInorganic or Ash

Sample

NO

Yes

Organic or Inorganic ?

Volatilizes when heated at 550oC

for 2 hours?

Volatile SolidOrganic

Fixed SolidInorganic or Ash

Sample

NO

Yes

TS TVS

TFS

Solids Species

TS

TSS

TDS

FSS

VSS

VDS

FDS

TVS

Solids Species

TS

TSS

TDS

FSS

VSS

VDS

FDS

TVS

Crystal Particles

Organic Particles

Soluble Organics

Dissolved Salts

Consistency

D.W. Hamilton, 2011. Consistency of Manure/Water Mixtures, OSU Factsheet BAE-1751.Stillwater,OK: Oklahoma Cooperative Extension Service.

Liquid Slurry Semi-Solid Solid

Pours like LiquidSpreads like LiquidNo Particles

Pours like LiquidSpreads like LiquidContains Particles

Moves as Liquidor Solid

Stacks like Solid

Pours like SolidStacks like Solid

USDA-NRCS. 1992. Agricultural Waste Management Field Handbook. Washington, D.C.: USDA Natural Resources Conservation Service.

0 5 10 15 20 25 30

Swine

Poultry

Beef(Feeder)

Dairy

SolidSemi-SolidSlurry

Slurry Semi-Solid Solid

Slurry Semi-Solid Solid

Slurry Semi-Solid Solid

Percent Total Solids (Wet Basis)

As Excreted

www.glossary.oilfield.slb.com

Rheological Definition of Consistency

Settling Type I Discrete Particle Settling Type II Flocculated Particle Settling Zone or Hindered Settling Compaction

Factors influencing SettlingParticle

Characteristics

Fluid

Characteristics

Collective

Characteristics

Settling Type I Discrete Particle Settling Type II Flocculated Particle Settling Zone or Hindered Settling Compaction

Discrete Particle Settling

Forces Acting on the Particle

Fg =d3 (p- f)g 6

Fd = Cd V2 d2 ρf

2 4

Stokes Law

ρp – ρf

Cd= ( )4

3 ρf

dgV2( )

Stokes Law

ρp – ρf

Cd= ( )4

3 ρf

dgV2( )

Cd = f (ρp,ρf,NFr)

Stokes Law

Cd = f (ρp,ρf,NFr,Nre)

Stokes Law

Cd = f (ρp,ρf,NFr,Nre,ψ)

Factors influencing SettlingParticle

Characteristics

Density

Size

Shape

Fluid

Characteristics

Density

Viscosity

Collective

Characteristics

Settling Type I Discrete Particle Settling Type II Flocculated Particle Settling Zone or Hindered Settling Compaction

Type II Settling

Factors influencing SettlingParticle

Characteristics

Density

Size

Shape

Charge

FluidCharacteristics

DensityViscosityPolarityIonic Strength

Collective

Characteristics

Settling Type I Discrete Particle Settling Type II Flocculated Particle Settling Zone or Hindered Settling Compaction

Zone Settling

Zone Settlingdxdt

= Vc

Factors influencing SettlingParticle

Characteristics

Density

Size

Shape

Charge

FluidCharacteristics

Density

Viscosity

Polarity

Ionic Strength

Collective

Characteristics

Concentration

Size Distribution

Settling Type I Discrete Particle Settling Type II Flocculated Particle Settling Zone or Hindered Settling Compaction

dxdt

= V

Compaction

Suspension of Slurries in Pipelines

VM1= 134Cd0.816D0.633Vo

1.63

VM2= 54.4Cd0.815D0.633Vo

1.63

Experimentally Derived Solution