Tuesday, November 6, 2007
194-12

Effect of Feedstock and Production Method on Pyrolysis Char's Properties for Use as an Agricultural Soil Amendment.

Keith R. Harris1, Julia Gaskin2, and K.C. Das1. (1) Dept. of Biology & Agricultural Engineering, University of Georgia, Driftmier Engineering Center, Athens, GA 30602, (2) Driftmier Engineering Center, University of Georgia, University of Georgia, Dept. of Biology & Agricultural Engineering, Athens, GA 30602

Pyrolyis char from biomass has potential as a soil amendment to improve soil quality including C and nutrient status.  Recent work indicates the feedstock and pyrolysis conditions such as temperature and the carrier gas effect important char characteristics for agricultural production.  Two readily available feedstocks in the southeastern United States are pine chips and poultry litter. We evaluated the effect of six char production methods on the total and available nutrients and cation exchange capacity (CEC).  Chars were produced at two temperatures – 400 and 500° C, and three carrier gas/activation regimes – steam carrier gas, nitrogen carrier gas, nitrogen as the carrier gas/steam activation.  Each of the six production combinations was replicated three times.  The resulting char was analyzed for total minerals, Mehlich I minerals, CEC, pH, water soluble carbon, and water extractable NH4-N and NO3-N.  There was a significant difference in nutrient concentration and CEC by feedstocks.  Poultry Litter pyrolyzed at 400° C had the highest CEC and nutrient content.  Pine chips were generally lower in CEC and nutrient content with no significant difference due to temperature or pyrolysis conditions.