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Abstract: Waste papers (newspaper, office paper, magazines and cardboard in this study) with 50–73% (w/w oven dry weight) carbohydrate contents have considerable potential as raw materials for bioethanol production. A particle size reduction step of wet blending prior to enzymatic hydrolysis of newspaper was found to increase the glucan conversion efficiency by up to 10%. High-solids loading hydrolysis at 15% (w/w) of four types of paper using two enzyme alternatives, Celluclast 1.5L supplemented with Novozyme 188 and Cellic Ctec 1 (Novozymes A/S, Demark), at various enzyme concentrations were successfully performed in a lab-scale overhead-stirred reactor. This work has identified the relative saccharification performance for the four types of paper and shows office paper and cardboard to be more suitable for producing bioethanol than newspaper or magazine paper. The experimental data were also very well described by a modified, simple three parameter glucan and xylan hydrolysis model. These findings provide the possibility for incorporating this validated kinetic model into process designs required for commercial scale bioethanol production from waste paper resources. [Copyright &y& Elsevier]

Abstract: As a significant fraction of municipal solid waste, waste paper is a potential source for producing bioethanol. In the present paper, bioethanol production from various waste papers (newspaper, office paper, cardboard and magazine) using an enzyme complex (Cellic Ctec 1) was evaluated from an economic standpoint. Four bases cases without pre-treatment and two state-of-the-art cases (including dilute acid pre-treatment for office paper and oxidative lime pre-treatment for newspaper) were constructed using laboratory experimental data, literature values, expert consultations and simulation using AspenPlus™. Several scenarios were also carried out to assess the sensitivity of various technology parameters (i.e. solids loading in saccharification, anaerobic digestion and fermentation efficiency, and sugar yields in pre-treatment). The sensitivity analysis suggested that the economic performance of bioethanol produced from waste paper could be improved significantly with an up to 25% reduction in minimum ethanol selling price (MESP) by increasing solids loading in saccharification and with a 6% reduction in MESP by enhancing fermentation efficiency. The comparison of the bioethanol selling price at pump (reference year 2009) and the petrol price showed bioethanol produced from newspaper, office paper and cardboard were economically competitive with petrol. [Copyright &y& Elsevier]