Theses and Dissertations


Lin Wei

Issuing Body

Mississippi State University


Thomasson, J. Alex

Committee Member

Bricka, R. Mark

Committee Member

Sui, Ruixiu

Committee Member

Fernando, Sandun D.

Date of Degree


Document Type

Graduate Thesis - Open Access


Biological Engineering

Degree Name

Master of Science


James Worth Bagley College of Engineering


Department of Agricultural and Biological Engineering


To examine the effects of operational parameters on syn-gas quality and biouel conversion rate under various running conditions, an experimental study of hardwood chip?s gasification in a downdraft gasifier was conducted. The resulting syn-gas had average low heating value of 5.79 ± 0.52 MJ/ Nm3, tar concentration of 14.06 ± 8.54 mg/Nm³, particulate concentration of 3.05 ± 1.79 mg/Nm³, hardwood conversion rate of 2.37±0.24 Nm³/kg, and carbon conversion rate of 98.01 ± 0.53%. This syn-gas is of acceptable quality to be used as a fuel source for internal combustion engine operations. The gasifier?s grate temperature had no evident effects on syn-gas quality and conversion rate within a range of 740 to 817oC. The particulate contents in preiltered syn-gas significantly increased when the gas flow rate changed from 36 to 56 Nm3/h. When the moisture content of hardwood chips increased, tar content of postiltered syn-gas significantly increased, and CO content significantly decreased.