Study on the viability of sewage sludge and Jatropha Curcas L. for bio-oil production

Investigation on the thermal degradation characteristics and other properties of Jatropha Curcas L. (JCL), sewage sludge and their combination was carried out to assess their viability for bio-oil production. Proximate and ultimate analysis was conducted on all the samples. Volatile matter content for sewage sludge was in the range of 23 to 40 weight percent while JCL was more than 85%. The volatile matter fraction of sewage sludge was enhanced up to 65 to 75% by mixing the sewage sludge with JCL, at a ratio of 30:70. Thermo-gravimetric (TG) analysis revealed the volatile matter content of the different samples increased proportionally to the bio-oil yield. JCL decomposed from 200°C-550°C whereas sewage sludge from 190°C-550°C. The combination feeds decomposed from 210°C-600°C. Production of bio-oil through pyrolysis is an interesting method since the majority of feedstock was made up of non-food resources and thus eliminating competition against food commodities. The groups of compounds detected were aromatics, ketones, amines, aldehydes and most importantly alkanes, alkenes which could be converted into valuable fuel as replacement for transportation fuel. Results indicated that a higher content of bio-oil could be produced from the combination feedstock and also produced low char compared to the individual sewage sludge sample.