Environmental assessment of bioproducts in development stage: The case of fiberboards made from coconut residues

Abstract

Fiberboards made from agro-industrial residues have been developed recently to add value to residues and decrease demand for wood and its byproducts. Nonetheless, new bioproducts made from residues are not inherently beneficial to the environment and bring no guarantee of improved efficiency in the use of resources, when compared to standard products. The impacts of these new bioproducts shall be compared to standard products to foster improvements and reduce potential harms to the environment from the development stage. This study assesses the environmental impacts of new coconut husk-based fiberboards, at development stage, aiming to prioritize those for future improvements and up-scaling. The following fiberboards are analyzed: i) MDF made exclusively of coir and fiber; ii) MDF UF made of coir and fiber bonded with urea-formaldehyde; and iii) HDF made only of coir and fiber. This assessment is performed considering different scenarios for allocation procedures (mass and economic, for current and future husk market value) and production scales (lab and pilot). The up-scaled husk-based fiberboards are compared to commercial wood-based panels to support decision about which products should be further improved. Short and long-term research agendas are proposed for reducing the potential impacts of these new products. This cradle to gate study is based on the ISO 14040 and 14044 standards for life cycle assessment, considering the production of fiberboards with 6.05*10−5 m3, at laboratory scale, and 1 m3, at pilot scale. The results show that husk-based MDF and HDF have high potential in terms of environmental performance. Nonetheless, they still require improvements to better compete with wood-based fiberboards when mass allocation is the criteria applied in the product modelling system. The hotspot analysis of MDF and HDF highlights the need to reduce impacts in husk transportation and processing, as well as in coconut farming. Two research agendas are proposed to improve MDF and HDF environmental performances: i) a short-term agenda, focused on reducing transportation distances and reusing nutrient rich effluents from husk processing in crop irrigation; and ii) a long-term agenda, focused on reducing the dependence of coconut farming in commercial fertilizers and improving the efficiency of irrigation. From this environmental assessment, the importance of applying both mass and economic allocation in the study of new bio-based products is shown. Furthermore, the need to design and evaluate up-scaled processes, at laboratory stage, in order to make meaningful choices among products is also highlighted. The methodological framework adopted in this study may support research teams searching to improve the environmental performance of products from laboratory stage.