Techno-economical study of NMMO and steam explosion pretreatments for ethanol and biogas production in Iran

Sugarcane bagasse is an abundant waste material. Production of biofuels, e.g., ethanol and Biogas, from bagasse is a sustainable remediation of this waste material. However, the major problem of this lignocellulosic material is its poor hydrolysis yield. Therefore a pretreatment was applied to have an economically feasible biofuel production process. Pretreatment with N-methylmorpholine-N-oxide (NMMO) is a new and efficient method in which the materials are treated at 120 °C in atmospheric pressure. Seam explosion is another moderate energy consuming pretreatment process. This type of pretreatment is an old process which is well studied in lab and pilot scale. In this study, two processes including NMMO pretreatment were developed for ethanol and biogas production (Scenario 1) and biogas production (Scenrio 2). These processes were compared with two similar processes (scenario 3 and 4) which utilize steam explosion pretreatment. The results indicated that total capital investment for building a plant in Iran utilizing 200,000 ton/year bagasse (dry weight) for scenarios 1 to 4 were 219, 246, 201 and 222 million Euros respectively. The manufacturing cost of ethanol and biogas were calculated and gasoline equivalent prices were 0.82, 0.57, 0.59 and 0.42 €/L for scenarios 1 to 4 respectively. Thus the most promising process was biogas production by steam explosion pretreatment.

Keywords:

Ethanol , Biogas , Pretreatment , Bagasse , NMMO , Steam explosion