Sand Settling Lanes - For Your Information · 3/18/2009 Sand Settling Lanes Joe Harner Dept Biological & Agricultural Engineering Kansas State University Manhattan, KS [email protected]

3/18/2009

Sand Settling Lanes

Joe HarnerDept Biological & Agricultural

EngineeringKansas State University

Manhattan, KS [email protected]

Univ. of Wisconsin Study

Issue Sand MattressLameness 15 % 25 %Hock/Legs 10.4 % 24.4 %

Culling 26 % 38 %Milk Production 26,058 24,064

Assumptions $12/cwt and 500 cows

Milk Production $23,928 Lameness $7,400 Culling $18,000

TOTAL $49,300 or Gross $500/cow/year

Andy Johnson – sand worth $1.66/cwt more compared to mattress

Sand in FreestallsCleanComfortableLower Bacteria

CostHandling

Positive Attitude & CommitmentRemoval

Stacking

Separation

SLM Systems are ComplexRemoval of manureMovement to sand recovery areaSand separation Move sand to storage areaMove liquids/solids to separation unitSolids removal processMove solids to storage areaTransfer liquid to storage area

Basics of Sand Separation

Separation based on DensityWater – 62 lbs / cubic footSand – 120 to 150 lbs / cubic foot

Mi i f i di tMixing of ingredientsWater – Manure – Sand

Suspension of mixtureDilution & High Velocity

Change velocity of suspended mixtureSand settles out if done correctly

3/18/2009

Why are some sand recovey systems successful?

Reclaiming sand requires water – the more the better

Total solids content in lagoon waterOne website – 1 % total solids3 % realistic5 % trouble5 % trouble

SourcesRainwaterRoof / Extraneous Pasture PondsMilk Parlor / Sprinkler System

Additional Water Required If 100 % of Waste Stream is Diluted

Solids in Recycle Water %

Separator Efficiency

0* 30/60* 60/80*

1 204 g/d/c 139 g/d/c 78 g/d/cg g g

2 95 63 34

3 58 37 20

4 40 25 12

5 29 17 8*Percent solids recovered and solids moisture content

500 Cow Dairy

Solids in Recycle Water %

Annual Water Volume

0* 30/60* 60/80*

Manure 3,100,000 2,800,000 1,900,000

Separator 0 310,000 1,200,000

1 40,500,000 28,100,000 8,000,000

3 13,900,000 9,500,000 5,500,000

5 8,600,000 5,800,000 3,300,000

*Percent solids recovered and solids moisture content

WI Dairy Producers

1

1.5

2

2.5

3

3.5

4

4.5

5

Tota

l Sol

ids

(%)

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

1.5 1.75 2.75 3.5 4 4.5

Lago

on C

apac

ity /

Cow

Satisfaction w/ Sand Quality

10-20 g/d/c

1-2 g/d/c

0

0.5

1.5 1.75 2.75 3.5 4 4.5Satisfaction w/Sand Quality

As the solid contents in recycled water increased, satisfaction with sand quality decreased proportionally

New vs Recycled Sand

Annual Sand Usage (55 lb/stall/day)20,000 lbs or 10 tons$10/ton = $100/stall/yr

Extra Water (20 gal/dy/stall)7,300 gallon/yr/stall$0.015/gal disposal = $110/stall

If all of the sand/stall/yr goes on 1 acre for 10 years = equals ½ inch of sand added to field (about 1 dump truck load per acre)

3/18/2009

Inorganic Bedding –Recycle Sand

Scrape System – Mechanical separation

Flush Plume System – Mechanical orFlush Plume System Mechanical or gravity separation

Flush System – Mechanical separationGravity separation

Flushing Criteria

1 ½ to 2 % slopeFlush wave velocity > 5 fps (7.5 to 10 fps)Contact time of 10 secondsContact time of 10 secondsWave depth of 3 to 4 inches10,000 gpm release rate1 to 1 ½ gallon per sq ft of floor area

Dilution ratio 6 to 1 (water to SLM)

DM and OM content of sand in free stalls

96.0

98.0

100.0 Fresh Recycled

98.0 98.2 98.9 98.4

90.0

92.0

94.0%

DM Ash

DM: SE = 0.08, P < 0.05Ash: SE = 0.03, P < 0.001

Sand usage

25

30

35

40

45

e st

all/d

ay

ControlPack Mat

41.5 40.1 40.8 28.0

0

5

10

15

20

lb. s

and/

free Sand Mizer

Sand Trap

Sand retaining devices differ (P < 0.01)

3 Types of Gravity Sand Recovery Systems

Sand Trap -- KS, PASand Lane -- KS, CA, FL, GA, TX, PA, MD, IA, MN, SD, WI, MISand Beach -- VA

The challenge is once sand is in suspension to maintain the water velocity until the desired location to settle the sand – once the water velocity slows down – sand will settle and must be resuspended if it occurs in a non desirable location.

3/18/2009

Gravity Sand Recovery

Reduce velocity to 1 to 2 fps Large volume of waterChange velocity quickly at exit g y q yDrying period requiredDirty water onlyRewash “dirty” sand

Sand Trap

40 ft wide, 40 ft long, 3 to 4 ft deepSand storage basin (7 to 21 days)Manure storage when scrapingg p gOutlet pipe design critical Sand will have <3 % organic matterSand may be more moisture

Flush Wave

Ramp

24 ft flat bottom10:1 Slope

18” Drain Pipe

Sand Trap –3 to 4 ft deep

SAND TRAP

Organic Matter vs Ash (sand)

50607080

ent Ash Organic

010203040

perc

e

S. Trap Solids Earth LagoonLocation of Nutrients

3/18/2009

Sand Lane

12 ft wide, >150 ft long, 1 ft deep1/10 to ¼ % slopeSand storage (<7 days)g ( y )Redistribute dirty sand Slope & flush volume critical Sand will have <1 % organic matter

Direction of Water Flow

Sand Lane Considerations -Length vs width Existing componentsEase of cleaningStack pad location P i i f ll

Direction of Water Flow

Proximity to freestalls

20-30’

4 ft Splash Walls

20-30’

Water Flow Direction

Sand will settle where water flow is interrupted or the water velocity is

Longer lanes result in settling more of the finer sand particles

interrupted or the water velocity is reduced. Design flow velocity is 1-2 fps – less than 1 fps results in organic matter settling.

3/18/2009

125-300 ft Lane Slope0.2 to 0.25 %

Sand Dewatering Pad

30 ft min

10 – 16 ft

Width based on inlet water volume

3/18/2009

Sand Beach

Variable width, length and depth1/10 to ¼ % slopeSand storage (<45 days)g ( y )Redistribute dirty sand Counter slope critical Sand will have <1 % organic matter

Sand Stack Pad

Inflow

12 ft

50-75 ft 3-5 % slope

SAND BEACH

15-24” 15-24” 15-24”

Flush Plume – Width is a

Transition from square to round tube causes sand to settle at entrance due to change in velocity

function of water velocity and channel slope

Solid Separation

Mechanical Systems –Stationery screensRoller pressesExtrusion units

Non Mechanical Systems -Weep WallsTrenchesSmall Lagoons

3/18/2009

Solid Separation

150 lbs/cow/day @ 87 % M.C.20 lbs solids & 130 lbs liquid

20 % Removal & 60 % M.C.10 lbs removed -- 140 lbs to lagoon

60 % Removal & 80 % M.C.60 lbs removed – 90 lbs to lagoon

Flushing or Scraping Systems

Sand separatorchange water velocity and drop out sand

Solid storage basin (trench basin)settle sand and organic matter from water

Lagoon or storage pondstorage structure for fresh and flush water THANK YOU -- QUESTIONS