Valorization of corn wastes: assess the environmental impacts in a life-cycle prospective

Circular economy plays a key role in increasing sustainability of the agricultural sector, given the countless possibilities of transforming crop residues and recyclable precious resources. Maize cultivation produces many residues, commonly left on the field, as a soil conditioner and source of nutrients, but some parts, such as corncob, have a marginal role. An evaluation of the environmental performances of valorization processes in a life-cycle perspective is important to compare the overall sustainability of the alternatives, maximizing their environmental benefit. This work reports the life cycle assessment results of four different corncob valorization scenarios: two as raw material to produce corncob pellet or corncob abrasive grits, other two for energy production, one by incineration, and one for biofuel production from fermentation. The results show the environmental impacts of these scenarios. Moreover, it gives indications for evaluating the benefits of turning agricultural wastes in secondary raw materials, promoting circular economy processes.