Tri Y Environmental Research Institute (Canada)

As plastic pollution is eroding our ecological environment at an alarming rate around the world, tracking the origins is a necessity for putting forward effective measures to prevent it. The building industry, as an important sector consuming plastic products and producing plastic wastes, is increasing application of thermal insulations to improve energy efficiency. However, most insulation materials have negative impact on the environment. With the strategies to boost sustainability of buildings, natural fibres have occurred in the market as promising raw materials for thermal insulations. This mini-review aims to describe the extent building insulations contributed to plastic pollution, and a possible solution to plastic pollution from natural fibres and their current shortcomings. Hopefully, the mini-review could advance the current knowledge on contribution of building materials, especially thermal insulations to the ubiquitous plastic pollution, and the potential of natural fibres for replacing the plastic insulations, which could accordingly help future development of sustainable green insulations.

This study describesthe optimization of a eucalyptus elementalchlorine-free (ECF) bleach plant to reduce adsorbable organic halogen(AOX). The correlations between operating conditions of each stageand pulp quality indices as well as the AOX content in wastewaterare analyzed, taking an ECF bleaching technology (D0EpPD1) as an example. The calculation models of pulp quality indicesand AOX content in wastewater are established. Then, an optimizationmodel aiming at minimizing AOX emission is structured. The model showsa good simulation effect because the errors between the calculatedand experimental values are within 6.3%. By analyzing the impact ofvarious operating conditions on AOX emissions, it was found that chlorinedioxide reduced in the D0 stage has the greatest impacton AOX. The optimization results show that AOX can be reduced from90.84 to 79.58 kg/h, a decrease of 12.5%. The verification experimentresults based on the optimized operating conditions showed that theexperimental results are in good agreement with the calculated resultsof the optimization model, and the effect of reducing AOX based onthe optimization model is obvious.