Gasification of Tibetan herb residue: Thermogravimetric analysis and experimental study.

Tibet is environment-ecologically vulnerable with very weak self-adjustment ability, thus risk control of Tibet herb residue (THR) through environment-sustainable disposal is in urgent need. Gasification is an effective way to dispose THR with product gas, which could meet the energy demand of local users. In this paper, gasification of THR was performed in TG-MS and a tube furnace. Effects of operating temperature and air equivalence ratio (ER) were investigated both in plain and Tibet conditions. TG-MS curves indicated most syngas were produced at 250–380 °C, and the reactions were slow down under Tibetan atmosphere. Gasification results indicated the optimum LHV gas of 5.59 MJ m−3, cold gas efficiency of 63.22% and carbon conversion efficiency of 68.87% were obtained when ER = 0.24 at 1000 °C under Tibetan pressure. LHV gas was low in Tibetan pressure which only reach 47% of that under plain condition when ER = 0.28. Results can provide insights into using gasification for treating THR and even other wastes environment-sustainably in Tibet. Image 1 • Gasification and TG-MS of Tibetan herb residue were conducted in Tibet atmosphere. • LHV of producing gas reached 5.59 MJ m−3 with equivalence ratio of 0.24 at 1000 °C. • LHV of gas in Tibetan pressure only reach 47% of the plain condition when ER = 0.28. • Herb residue gasification is considered an environment-sustainable option in Tibet. [ABSTRACT FROM AUTHOR]