Architectural technologies for life environment: improving sustainability by reusing wastes in novel geopolymeric mortars

Abstract

Recently, implementing construction to a more sustainable industry has become a focal point in the international debate due to the huge volume of non-renewvable raw materials and energy consumed every year, along with the significant emissions of green-house gases and global warming, often associated to the supplementing industries. Besides, valorisation and reuse of industrial wastes and by-products is a viable alternative to the traditional industrial system, becoming a compelling topic to improve processes and materials sustainability. This paper fo- cuses on the development of a novel class of green geopolymers, worldwide considered a solid and sustainable alternative to Portland cement. Among the most advanced studies on construc- tion materials, many are the accredited advantages in boosting geopolimers as such as excellent properties, optimal durability, low CO2 emissions, low-cost and reproducible manufacture, etc. More particularly, this work discusses an alternative recycling procedure of kraft pulp indus- trial wastes to manufacture the specimens. Requirement, mix design, manufacture and charac- terisation of the novel mortars are reported in light of the relevant application in construction. Furthermore, a preliminary industrial setup and product cost assessment are predicted in order to estimate the commercial feasibility of the operation. Tests indicate that the produced ge- opolymers may efficiently substitute the ordinary Portland cement and can be used as structural material in construction according to the most relevant regulations and technical requirement. More over, other applications may be hypothesised in light of the analysed materials features. Finally, this study indicates that these novel mortars represent an efficient solution to reduce the environmental footprint associated with waste disposal whose valorisation and reuse in geopol- ymers technology is a suboptimal way of gaining financial surplus for the involved industrial players, while contributes for the implementation of a desirable circular economy, centered in the EU and international debate.