Physical and chemical effects of using dregs on industrial composting of sludge from Kraft pulp industry

Abstract

The beneficial use of solid wastes could be an alternative for landfill management. However, there are few rigorous studies that have led to estimate the impact of these wastes on the environment. The most suitable combination of these wastes was studied based on a 32 factorial design and it was found that the dregs dose should not exceed 12.5% (v/v) with an optimal ratio of dregs:bark equal to 0.25. The results indicate that the process was successful and showed an evolution of its typical temperature. Similarly, in most of the mixtures the termophilic temperature was exceeded. The tendency of N-NO3- and N-NH4+ contents indicated the existence of a mature compost, as well as seed germination rates.