Waste Paper as Promising Feedstock for Production of Biofuel

Modern approach to utilization of non-edible biomass is its conversion to glucose, and the following fermentation of the sugar into final bioproducts. Among various biomass types, the waste of office paper is distinguished by increased content of cellulose and negligible content of lignin; therefore it can be a suitable feedstock for bioconversion into valuable bioproducts. In this article, an advanced technology has been proposed for complete utilization of the paper waste by bioconversion. The technology is comprised of the following main steps: (1). Redispersion of the waste paper and then screening of the pulp in order to separate fibers from mineral fillers; (2). Acidification and washing of the fibers to remove the residual calcium carbonate; (3). High-solids enzymatic hydrolysis of the demineralized paper to obtain fermentable sugar - glucose; and (4). Fermentation of the glucose into biofuel. As a result, from 1 ton of the waste office paper about 280L of bioethanol can be produced that have capacity of the heat energy of 1680kWh. Besides, there remain by-products of the processing including about 260kg of residual fibers and about 270kg of mineral fillers that can be used repeatedly in the papermaking. Thus, the waste paper can be utilized completely for production of the valuable bioproduct and recycled paper materials.