Post-harvest processing methods for reduction of silica and alkali metals in wheat straw.
Silica and alkali metals in wheat straw limit its use for bioenergy and gasification. Slag deposits occur via the eutectic melting of SiO2 with K2O, trapping chlorides at surfaces and causing corrosion. A minimum melting point of 950 degrees C is desirable, corresponding to an SiO2:K2O weight ratio of about 3:1. Mild chemical treatments were used to reduce Si, K, and Cl, while varying temperature, concentration, % solids, and time. Dilute acid was more effective at removing K and Cl, while dilute alkali was more effective for Si. Reduction of minerals in this manner may prove economical for increasing utilization of the straw for combustion or gasification.
Thompson
David N
DN
Biotechnology Department, Idaho National Engineering and Environmental Laboratory, PO Box 1625, Idaho Falls, ID 83415-2203, USA. thomdn@inel.gov
Shaw
Peter G
PG
Lacey
Jeffrey A
JA
D000383:Agriculture / Q000379:methods; D000821:Animal Feed; D001709:Biotechnology / Q000379:methods; D002241:Carbohydrates / Q000032:analysis; D002482:Cellulose / Q000032:analysis; D002712:Chlorides / Q000302:isolation & purification; D008031:Lignin / Q000032:analysis; D008669:Metallurgy / Q000379:methods; D008670:Metals / Q000302:isolation & purification*; D012822:Silicon Dioxide / Q000302:isolation & purification*; D014908:Triticum / Q000737:chemistry*
D002241:Carbohydrates; D002712:Chlorides; D008670:Metals; D012822:Silicon Dioxide; D002482:Cellulose; D008031:Lignin