Alternative Technologies for Biofuels Production in Kraft Pulp Mills—Potential and Prospects

Abstract

Abstract:The current global conditions provide the pulp mill new opportunities beyond the traditional production of cellulose. Due to stricter environmental regulations, volatility of oil price, energy policies and also the global competitiveness, the challenges for the pulp industry are many. They range from replacing fossil fuels with renewable energy sources to the export of biofuels, chemicals and biomaterials through the implementation of biorefineries. In spite of the enhanced maturity of various bio and thermo-chemical conversion processes, the economic viability becomes an impediment when considering the effective implementation on an industrial scale. In the case of kraft pulp mills, favorable conditions for biofuels production can be created due to the availability of wood residues and generation of black liquor. The objective of this article is to give an overview of the technologies related to the production of alternative biofuels in the kraft pulp mills and discuss their potential and prospects in the present and future scenario.

Side by Side Comparison of Chemical Compounds Generated by Aqueous Pretreatments of Maize Stover, Miscanthus and Sugarcane Bagasse

“…5, Table 2). In theory, these fatty acids could be readily skimmed as sodium soap from the complex pretreatment liquor prior pH neutralisation, in a similar manner to that of tall oil being isolated during the kraft pulp process of coniferous wood [49]. The resulting soap has several potential applications, among which the esterification of the fatty acids with methanol or ethanol would produce fatty acid methyl or ethyl esters, respectively, which is biodiesel [49][50][51].…”

Integrating a Biorefinery into an Operating Kraft Mill

“…Dissolving pulp mills are not included. Figure 1 shows some of the multiple options for extracting value from the process flow of a biorefinery integrated with a kraft mill (Hamaguchi et al 2012). The main paths to fuels and chemicals are through wood residue, bark, pins, fines, or hog fuel that can be de-ashed, dried, and ground.…”

“…Integration offers a cost saving in shared energy resources, biomass supply lines, creating value from underutilized waste streams and manufacturing expertise. A more specific SWOT analysis is needed for each type of feedstock, process technology, and product combination, producing an array of SWOT matrices that define platforms and success factors (Kretschmer 2014 Several reviews give a detailed view of how biorefineries may be deployed in a kraft mill (Ragauskas et al 2006;Hamaguchi et al 2012Hamaguchi et al , 2013Hakovirta 2014;Mariano 2015). Detailed descriptions of biorefinery plans and early commercial development by location and technology are available (Pytlar 2010;Mendell et al 2011;Cellulosic Biofuels -Industry Progress Report 2012Tuuttila and Joelsson 2012;Bacovsky et al 2013;Bergström and Matisons 2014;Laqua 2015).…”

Effects of Pretreatments on Yields, Selectivity and Properties of Products from Pyrolysis of Phragmites australis (Common Reeds)

“…While energy densification increases the quality and efficiency of the biomass for use in pyrolysis, torrefaction also gives the biomass other desirable qualities. Torrefaction reduces the hydroscopic property of biomass, making the biomass absorb less moisture when stored [37]. Torrefied biomass also contains improved grindability characteristics [38].…”