BAE2023(2012)[3] - Biosystems and Agricultural Engineering

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Transcript BAE2023(2012)[3] - Biosystems and Agricultural Engineering

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
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Solids Speciation
Suspensions
Consistency
Rheology
Solids Settling
Flow of Suspensions in Pipelines
Slurry: mixture of solids and liquids
What is a solid?
Liquid
NO
Sample
Remains
after heating at 103o C
for 24 hours
Yes
Solid
What is a solid?
Liquid
NO
Sample
Remains
after heating at 103o C
for 24 hours
Yes
Mass of Solids
=
Mass of Sample
Solid
TS
Suspended or Dissolved ?
Suspended
NO
Sample
Passes through
1.5 Micron Diameter
Hole?
Yes
Dissolved
Particle Type
Clay
Silt
Sand
Bacteria
Viruses
Cysts
Algae
Separation Process
Asbestos Fibers
Screens
Ultra Filter
0.01
Fabric Filters
Settling
Micro Filter
Centrifuge
Media Filter
0.1
1.0
10.0
100
1,000
Particle Size (micron)
Hamilton D.W. 2011. Solids Content of Wastewater and Manure.
OSU Factsheet BAE-1759. Stillwater, OK:Oklahoma Cooperative Extension Service.
Suspended or Dissolved ?
Suspended
TSS
NO
Sample
TS
Passes through
1.5 Micron Diameter
Hole?
Yes
Dissolved
TDS
100
0
90
10
80
20
70
30
60
40
50
50
0
% Retained
% Passing
Distribution of Suspended Solids
500 1,000 1,500 2,000 2,500 3,000 3,500
Seive Opening (microns)
Fine ground corn
Cracked Corn
Whole 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
Organic or Inorganic ?
Fixed Solid
Inorganic or Ash
NO
Sample
Volatilizes when
heated at 550oC
for 2 hours?
Yes
Volatile Solid
Organic
Organic or Inorganic ?
Fixed Solid
Inorganic or Ash
TFS
NO
Sample
TS
Volatilizes when
heated at 550oC
for 2 hours?
Yes
Volatile Solid
Organic
TVS
Solids Species
FSS
TSS
VSS
TS
TVS
VDS
TDS
FDS
Solids Species
Crystal Particles
FSS
TSS
Organic Particles
VSS
TS
TVS
VDS
TDS
Soluble Organics
FDS
Dissolved Salts
Consistency
Slurry
Liquid
Pours like Liquid
Spreads like Liquid
No Particles
Pours like Liquid
Spreads like Liquid
Contains Particles
Semi-Solid
Moves as Liquid
or Solid
Stacks like Solid
Solid
Pours like Solid
Stacks like Solid
D.W. Hamilton, 2011. Consistency of Manure/Water Mixtures, OSU Factsheet
BAE-1751.Stillwater,OK: Oklahoma Cooperative Extension Service.
As Excreted
Swine
Slurry
Poultry
Semi-Solid
Slurry
Beef
(Feeder)
Slurry
Dairy
Slurry
0
5
Solid
Semi-Solid
Semi-Solid
Solid
Semi-Solid
10
15
Solid
Solid
20
25
Percent Total Solids (Wet Basis)
USDA-NRCS. 1992. Agricultural Waste Management Field Handbook.
Washington, D.C.: USDA Natural Resources Conservation Service.
30
Rheological Definition of Consistency
www.glossary.oilfield.slb.com
Settling
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Type I Discrete Particle Settling
Type II Flocculated Particle Settling
Zone or Hindered Settling
Compaction
Factors influencing Settling
Particle
Characteristics
Fluid
Characteristics
Collective
Characteristics
Settling
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Type I Discrete Particle Settling
Type II Flocculated Particle Settling
Zone or Hindered Settling
Compaction
Discrete Particle Settling
Forces Acting on the Particle
Fd = Cd V2 pd2 ρf
2 4
Fg = p d3 (rp- rf)g
6
Stokes Law
Cd
=
4
3
(
ρp – ρ f
ρf
dg
V2
)( )
Stokes Law
Cd
=
4
3
(
ρp – ρ f
ρf
dg
V2
)( )
Cd = f (ρp,ρf,NFr)
Stokes Law
Cd = f (ρp,ρf,NFr,Nre)
Stokes Law
Cd = f (ρp,ρf,NFr,Nre,ψ)
Factors influencing Settling
Particle
Characteristics
Fluid
Characteristics
Density
Size
Shape
Density
Viscosity
Collective
Characteristics
Settling
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Type I Discrete Particle Settling
Type II Flocculated Particle Settling
Zone or Hindered Settling
Compaction
Type II Settling
Factors influencing Settling
Particle
Characteristics
Fluid
Characteristics
Density
Size
Shape
Charge
Density
Viscosity
Polarity
Ionic Strength
Collective
Characteristics
Settling
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Type I Discrete Particle Settling
Type II Flocculated Particle Settling
Zone or Hindered Settling
Compaction
Zone Settling
Zone Settling
dx = V
c
dt
Factors influencing Settling
Particle
Characteristics
Fluid
Characteristics
Collective
Characteristics
Density
Size
Shape
Charge
Density
Viscosity
Polarity
Ionic Strength
Concentration
Size Distribution
Settling
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Type I Discrete Particle Settling
Type II Flocculated Particle Settling
Zone or Hindered Settling
Compaction
Compaction
dx = V
dt
Suspension of Slurries in Pipelines
VM1= 134Cd0.816D0.633Vo1.63
VM2= 54.4Cd0.815D0.633Vo1.63
Experimentally Derived Solution