Tecno-economic assessment of CNF and CMF production from forestry industrial wastes for a multiproduct biorefinery

CLAUSER, N.M.; FELISSIA, F.E.; AREA, M.C.; VALLEJOS, M.E.

Conferencia; XXV TECNICELPA ? International Forest, Pulp and Paper Conference and XI CIADICYP ? Iberoamerican Congress on Pulp and Paper Research; 2021

TECNICELPA

Themanufacture of nanomaterials from sustainable and renewable resources extendsthe promising potentials of nanotechnology. Cellulose nanofibrillated (CNF) andcellulose microfibrillated (CMF) revolutionized the field of biobasednanomaterials because of their unique characteristics and properties. In theproduction processes, biomass is processed to remove hemicelluloses, lignin,extractives, and inorganics. These pretreatments, which involve fractionationand bleaching, are usually applied for the manufacturing of biofuels and highvalueadded products. The solid material, containing mainly cellulose, issubjected to an intensive mechanical process in aqueous suspensions. Productionof these materials is an interdisciplinary field. Intense investigations havebeen focusing on these materials to make them potential candidates for theprofit of the industrial sector, mainly related to technical assessments ofproduction pathways, evaluation of properties, strategies for nanocellulosesurface modifications, and its applications. However, a technoeconomicassessment is necessary to determine and analyze variables that most affecttheproduction processes.Initially,a block diagram and complete mass and energy balance must be developed andmodeled. Then, the process is simulated, and the techno-economic analysis iscarried out with a sensitivity assessment to obtain the most importantvariables, parameters, and potential opportunities for cost optimization. Thisstudy is the starting point of a techno-economic assessment for the production processof CNF and CMF from forest-industrial waste (see Graphical abstract). In theproposed study, several software tools could be used. For mass and energybalances, software like Aspen Plus, Aspen Hysys, and Microsoft Excel. Foroptimization, GAMS software. Techno-economic assessment will be developed inMicrosoft Excel, and finally, a sensitivity analysis will be carried out byOracle Crystal Ball software.An annualdisponibility of about 100,000 tons of dry sawdust of eucalyptus as rawmaterial was assumed. Global yields after pretreatment (hemicellulosesextraction and delignification) are about 30 % of initial dry material sawdust.From this process, it is possible to obtain hemicellulosic sugars and ligninthat could be valorized and, from the bleached pulp, about 3 million tons ofCNF and CMF (1% of consistency).Reportedenergy consumptions of the mechanical step for CNF and CMF production from woodpulp can range from 500 kWh/t to 70 MWh/t, depending on the pulp and theapplied treatment. Production costs reported starts at USD 2/kg (withoutinformation on how the cost estimation was performed) and could reach USD 17/kg (dry equivalent), taking into account depreciation.Energyconsumption and production costs of the reported literature could reach veryhigh values, so the next steps of this study are to determine and analyzeenergy consumption, supplies andcapital investment followed by integrationstrategies, and sensitivity and environmental assessments, to determine anddevelop alternatives for process improvement