1. Covered Anaerobic Digester Developing an Environmental Management System (EMS) Approach for Agriculture and Agribusiness Dec. 18, 2000 Julian Barham Barham Farms Zebulon, NC

2. Case Study - Barham Farm Located - Johnston County, NC modern swine farm populated in 1994 owned and managed by Julian and Elaine Barham

3. Background Information 4000 sow - farrow to wean 4 gestation barns 2 farrowing barns slatted floors (grates) shallow pit/recharge flush pit 4/8 day cycle waste gravity flow

4. Process Diagram

5. 1994 - 1996 Effluent from barns to anaerobic lagoon 40,000 gallons/day (total solids < 1.0%) lagoon surface = 6 + acres

6. Traditional Anaerobic Lagoon Design Freeboard Rainfall/Storms Storage Treatment Sludge Field Application EvaporationEmissions

7. Covered Anaerobic Digester ? 1 Odor Control 2 Energy Resource 3 Ammonia Emissions 4 Rainfall Exclusion (*)

8. Anaerobic Digester and Storage pond Treatment Sludge Biogas Anaerobic DigesterStorage Pond Rainfall Digester effluent

9. Lagoon Cover Design partial cover ? bank to bank ? lower cost (?) rainwater into lagoon odor reduction high maintenance rain exclusion no emissions (sealed) biogas storage low maintenance

10. Partial Cover - Practical Application !

11. Bank to Bank Cover - Practical Application

12. Things Involved Biogas Methane + CO 2 + H 2 S Greenhouse gas Options Flare IC Engine Micro Turbine Burner/Boiler

13. Equipment Needed Boiler for hot water - 10,000 gallon hot water storage - hot water for space heating and mats Engine for co-generation - 120 KW for peak shaving - engine heat recovery - hot water

14. Lagoon Performance

15. Covered Anaerobic Digester Effluent Organic Carbon - reduced 85% TKN - reduced 30% Total P - reduced 75% K - reduced 20% Ref: ASAE Proceedings 8th InterNatl Symp. Oct 2000 Eval. of Alternat. Waste Sys.

16. Digester Effluent Use: Apply at agronomic rate to low value hayland!

17. Digester Effluent Use: Nutrient rich for high value produce in green house environment!

18. Benefits Seen Biofilter - low energy input process Reduce Ammonia Emissions (NH 4 to NO 3) Lower pH

19. Greenhouse

20. Other Results and Conclusion It’s not “A Sows Ear to a Silk Purse” but Demonstrated Energy Resource Reduced Emissions Marketable Produce Manageable System ?