biosystems and agricultural engineering university of kentucky · joe taraba extension professor...

Joe TarabaExtension Professor

Biosystems and Agricultural Engineering

University of Kentucky

US and European approaches to reducing animal confinement emissions

Present media moisture control strategies

Green house gas generation, removal and emissions as affected by media moisture

New concept of viewing microbial populations on media in biofilter

New moisture control strategy

Application of moderate pressure biofiltration

Large amount of research and extension information concerning effectiveness and design has been developed in the upper Midwest since the mid-90s

•Iowa, Wisconsin, South Dakota, Minnesota, Nebraska, Illinois, Indiana

•Larry Jacobson, Kevin Janni, Dick Nicolai, Bob Burns, Ted Funk, Rick Stowell, Dave Schmidt, Al Heber

• Odorants:Carboxylic acids butyric acid, valeric acid, ……

Alcohols ethanol, butanol, ......

Phenolics cresol, dimethyl phenol, ……

Aldehydes acetaldehyde, acrolein, …..

Esters ethyl acetate, butylacetate, ……

Nitrogen heterocycles indole, skatole, ……

Amines methylamine, pentylamine, ……

Sulfides dimethylsulphide, …….

Mercaptans methanethiol, ……

168 Compounds Found

• Toxics:AmmoniaHydrogen sulfide

• Greenhouse gases (GHGs):Carbon dioxideMethane (~ 30 x CO2)

Nitrous oxide (~ 300 x CO2) (evolved during treatment process)

Scale of the Concern for Animal Confinement Gas Emissions

• Biofilter technique using media to support microorganisms to capture and biologically degrade pollutants.

• Bio-scrubber/bio-trickle filterwater, w/o nutrients, flowing over media countercurrent to gas flow.

• Biofilm aggregate of microorganisms, embedded within a self-produced extracellular polymeric matrix, adhering to a surface.

Wikipedia – accessed 1/21/2011Devinny and Ramesh. 2005.Chemical Engineering Journal 113, 187–196

• Filtration - separation of solids from fluids (liquids or gases) by using a medium through which only the fluid can pass

• Wet Scrubber - spray of liquid droplets or film covering a media capturing particulate matter and dissolving or absorbing gaseous pollutants into the liquid.

• Absorption - molecules are taken up by the volume, not by the surface

• Adsorption - adhesion of atoms, ions, biomolecules or molecules to a surface

Wikipedia – accessed 1/21/2011

• Reduce the generation of gases.Alter the microbial populations (change

microbial environment).Reduce the food for microbes.

• Dilute or disperse the gases as they leave the site.

• Capture and treat the gases before they leave the site.

Air Quality Around Production Facilities and Land Application Sites, Lorimor and Schmidt LPES, 2008

• Diet

• Add bedding

• Pit additives

Air Quality Around Production Facilities and Land Application Sites, Lorimor and Schmidt LPES, 2008

• Setback distances

• Wind breaks or shelterbelts

• Stacks

Air Quality Around Production Facilities and Land Application Sites, Lorimor and Schmidt LPES, 2008

Environmental issues In livestock production Home study course. http://www3.abe.iastate.edu/homestudy/odorassess.htm

Biofilters use microbes to convert odorousgases to carbon dioxide and water.

Air Quality Around Production Facilities and Land Application Sites, Lorimor and Schmidt LPES, 2008

• Typically applied to total ventilation exhaust

• Multiple stage treatment

• Pressure drop ~ 0.6- 0.7 “ H2O

• Small footprint

• Higher management input

Gates, 2007

Exhaust Air Treatment Systems for Animal Housing Facilities: Techniques - Performance – Costs. KTBL, Publ. no. 464, 2008

Gates, 2007

Exhaust Air Treatment Systems for Animal Housing Facilities: Techniques -Performance – Costs. KTBL, Publ. no. 464, 2008

Exhaust Air Treatment Systems for Animal Housing Facilities: Techniques - Performance – Costs. KTBL, Publ. no. 464, 2008

Exhaust Air Treatment Systems for Animal Housing Facilities: Techniques - Performance – Costs. KTBL, Publ. no. 464, 2008

•Higher pressure drop

•High air treatment volume

•Sludge and wastewater storage

• Single stage - biofiltration

• Partial treatment of ventilation air - pit ventilation

• Low pressure drop ~ 0.1 – 0.25 “H2O

• Large footprint

Jacobson, et al. ASABE, 2006

Jacobson, et al. ASABE, 2006

Nicolai, et al, 2008. Mitigating air emissions from animal feeding

operations Conf.

Horizontal Filter Vertical Filter

Schmidt and Janni, Univ of Minn., 2009

Air Distribution Plenum

Nicolai and Lefers, NPPC Report, 2008

Tapered wall for uniform gas flow

• Maintain low pressure drop

• Sufficient void space in media bed

• Type/composition/size of media

• Air treatment volume

• Moisture control (range 40-60% wb)

• 90% odor reduction

• 90% hydrogen sulfide reduction

• 80% ammonia reduction

Nicolai and Lefers, NPPC Report, 2008

Horizontal Biofilter

Vertical BiofilterSchmidt and Janni, Univ of Minn., 2009

How Moisture Level of Media Affects

Generation/Degradation in Biofilter

Nicolai, et al, 2008. Mitigating air emissions from animal feeding operations Conf.

Oxygen Level

Biofilm of sulfate-reducing, anaerobic bacteria Desulfovibrio

desulfuricans grown on a hematite surface

Biofilm in anaerobic methane generator

Biofilm on human tooth enamel

Scanning electron micrograph of Ceriporiopsis subvermisporamycelium on wood, Courtesy R.

Blanchett, University of Minnesota

Xylem vessels with bacteria aggregated along the walls. UV light

illuminates cytoplasm in cells.Sophie Grall and Charles Manceau. Applied and Environmental Microbiology, April 2003, p. 1904-1912, Vol. 69, No. 4.

Kenaf, showing the open internal spaces containing microbial cells.

Distribution of physiological properties within an aggregate/particle. Lines represent isobars of O2

concentration (%). Coyne, 2010.

Typical Soil Aggregate Sylvia, et al. 2005. Prin. & Appl. Of Soil Micro.

Pearson. Upper Saddle, NJ.

Nitrification and Denitrification Processes:

NH3 NO2- NO3

-NH2OH

NON2ON2

Nitrification

Nitro

gen F

ixatio

n

NitrificationNitrification

De

nitrific

atio

n

DenitrificationDenitrification

Denitrification

Fungus has degraded some cells completely.

Diseases of Forest and Shade Trees©2006 Robert A. Blanchette

Increased total pore volume

Sawdust based compost~ 0.1 – 0.2 in

Water Activity ~ 1

Water Activity > 0.95

Water Activity < 0.90

GHG Production Affected by Moisture Content of Media

NH

3Degr

adation

and

CH

4Gene

ration

(g/

m3h)

N2 O

Gene

ration (g/m

3h)

0.9

0.91

0.92

0.93

0.94

0.95

0.96

0.97

0.98

0.99

1

0

5

10

15

20

25

30 35 40 45 50 55 60 65 70

Wate

r Act

ivity

Pore

Diamete

r (µ

m)

Compost Moisture Content (%-wb)

Maximum Pore Diameter (µm) Water Activity

Multi-Stage Biofilter Concept

• Application to deep beds

• Finer texture media ~ 0.1 – 0.2 in

• Higher pressure drops~ 1 – 3 “ H2O

• Smaller footprint

Humidified Air Stream

• Moisture measurement with capacitance wire-grid plates

• Position capacitance plates

• Soaker hose configuration

• Soaker hose position Funk, U of Ill, 2010

To maintain aerobic conditions in biofilter media a minimum of 100 parts of oxygen should be provided for each part of oxidizable gas (Williams and Miller 1992)