Journeys on a Limping MuleWhat We Know About Bioreactors

• One who knows and knows that he knows... His horse of wisdom will reach the skies.

• One who knows, but doesn't know that he knows... He is fast asleep, so you should wake him up!

• One who doesn't know, but knows that he doesn't know... His limping mule will eventually get him home.

• One who doesn't know and doesn't know that he doesn't know... He will be eternally lost in his hopeless oblivion!

Ibn Yamin Faryumadi (1286-1368)

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UU

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Why Bioreactors ?a Proven technology

a Requires no modification of current practices

a No land taken out of production

a No decrease in drainage effectiveness

a Very low maintenance

a Estimated life - 10 to 15 years

a Cost effective

0 200 400 600 800

5

10

15

20

25

30C

once

ntra

tion

of N

itrat

e-N

(mg/

L)

Hydraulic Retention Time (mins)

Corncob Mix data points Wood mix data points Corncob Mix fitted line Wood Mix fitted line

cbt-expexp1AR

CD=68%

Removal Efficacy is a Function of Oxygen Saturation, Carbon Source and Retention Time

0 200 400 600 800 1000 1200 1400

5

10

15

Hydraulic retention time (mins)

20c

50c

100c

150c

200c

250c

20

40

60

80

100

Measured Points (2oC)

% N

itra

te R

emai

ning

Con

cent

ratio

n of

Nitr

ate-

N (m

g/L

)

Removal Efficacy is a Function of Temperature

First Generation Bioreactors

CapacityControlStructure

5’ Soil Backfill

Woodchips

Trench bottom 1’ Below tile invert

Section of perforated tile

Length/width dependent on contributing area

DiversionStructure

Second Generation Bioreactors

Capacity controlstructure

5’ section of non-perforated tile

Diversionstructure

Top View

5’ Soil backfill

Combinationstructure

5’ Soil backfill

Non-perforated tile

Perforated tile

60 minutes after injection

0 100 200 300 400 500 600

X (cm )

0

100

200

300

400

500

600

Y (c

m)

0510152025303540455055606570758085

0 100 200 300 400 500 600

X (cm )

0

100

200

300

400

500

600

Y (c

m)

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

120 minutes after injection

Dissolved MeHg in Bioreactor Inlets

-Eight non-detects-Eight non-detects

-Six samples contained detectable MeHg-Six samples contained detectable MeHg

- Maximum: - Maximum: 0.16 ng/L0.16 ng/L

- Average:- Average: 0.09 ng/L0.09 ng/L

Dissolved MeHg in Bioreactor Outlets

CapacityControlStructure

5’ Soil Backfill

Woodchips

Trench bottom at thetile invert level

Length/width dependent on contributing area

DiversionStructure

Third Generation Bioreactors

Section of perforated tile

87.576.565.554.543.532.521.510.50

150,000

140,000

130,000

120,000

110,000

100,000

90,000

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

14131211109876543210

1,000

950

900

850

800

750

700

650

600

550

500

450

400

350

300

250

200

150

100

50

0

No nitrous oxide was released from the system

Phosphorus Removal Chamber

Solid pipe

Solid pipe

Perforated pipePerforated pipe

Plastic Liner

SiteDrainage

Area (acres)

Bioreactor Area

(square feet)

Loading Density(acres/100 sq.

feet)Decatur West 5 400 1.25De Land West 28 930 3.00

Amenia 15 400 3.75Decatur East 16 400 4.00

Bloomington North 20 400 5.00De Land North 39 560 7.00De Land East 34 400 8.50Mount Zion 70 400 17.5

BIOREACTOR EFFICACY CURVELake Decatur and Lake Bloomington Watersheds

Lr = 87.29Ld-0.343

R² = 0.99

Lr = 95.31Ld-0.361

R² = 0.94

Lr = 95.42Ld-0.435

R² = 0.44

010

20304050

607080

90100

0 5 10 15 20

Loading Density Ld ( Acres/100 sq.feet of the bioreactor)

Load

Red

uctio

n Lr

(%)

2008 2009 2010 2008 2008-2009 2008-2010

Chipometer

ThankYou!

Richard CookeDepartment of

Agricultural and Biological Engineering

University of Illinois