Análisis del posible uso del residuo de lodo de papel como material cementante suplementario

Fontalvo Pérez, Juan Esteban | 2022

The paper industry produces a waste known as sludge (a mixture of kaolin and cellulose fibers) and due to the high generation of this waste and the environmental burden that its disposal represents, the objective of this research is to analyze whether this sludge from paper manufacturing can be used to partially replace cement. This research contemplated two forms of study for kraft paper (KP) and soft paper (SP) sludge. The first consisted of investigating the calcination temperature of the sludge using TGA to optimize the pozzolanic activity of the ashes, and the second was the variable with the milling process. The pozzolanic activity of the sludge studied showed that the ashes obtained at 800°C had the highest pozzolanic activity. The particle morphology study showed that the particles of both types of sludge that were subjected to the calcination process are finer than the particles of the samples that were subjected to the milling process, since the percentage of these calcined sludges that were retained in the 35 μm sieve was higher, and this was essential to determine which of the two processes would be the most feasible for the different chemical and physical processes that these sludges can have with the adherence in their mixtures. Likewise, DRX showed phases such as calcite, talc, silica and cellulose, while SEM- EDS reflected the presence of typical microstructure such as calcium, oxygen, silicon, aluminum and iron content. The compressive strength results show that the tested dosages reached mechanical strength percentages of 11.48% for the ground kraft paper, 56.82% for the calcined kraft paper, 57.82% for the calcined soft paper and 24.61% for the ground soft paper, with respect to the control sample, at 28 days. Paper sludge is a sustainable option for use in construction.