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Methods for Facilitating Microbial Growth on Pulp Mill Waste Streams and Characterization of the Biodegradation Potential of Cultured Microbes
Published on: December 12, 2013
Pulp and paper plant wastes valorisation in bituminous mixes
R Modolo1, A Benta, V M Ferreira
1University of Aveiro, Civil Engineering Department/CICECO, 3810-193 Aveiro, Portugal. regina.modolo@ua.pt
Waste Management (New York, N.Y.)
|December 8, 2009
Summary
Pulp and paper inorganic wastes, dregs and grits, show potential for use in bituminous mixtures. Grits perform well as aggregate replacements in road construction, while dregs require treatment to ensure mix stability.
Area of Science:
- Environmental Science
- Materials Science
- Civil Engineering
Background:
- Growing waste disposal concerns necessitate sustainable solutions.
- Pulp and paper industry generates significant inorganic waste (dregs and grits).
- Utilizing these wastes in construction can mitigate environmental impact.
Purpose of the Study:
- To evaluate the feasibility of using pulp and paper inorganic wastes (dregs and grits) as aggregate substitutes in bituminous mixtures.
- To assess the environmental benefits of reducing waste disposal through this application.
Main Methods:
- Chemical and physical characterization of dregs and grits.
- Testing waste materials for suitability as aggregates in bituminous mixtures.
- Preparation of bituminous mixtures with varying percentages of waste replacement.
- Comparative analysis of mechanical properties with standard reference mixtures.
Main Results:
- Grits demonstrated favorable performance, suggesting direct industrial application in road construction.
- Dregs exhibited potential but require pre-treatment to address water sensitivity issues.
- Mechanical properties of waste-containing mixtures were evaluated against control samples.
Conclusions:
- Pulp and paper inorganic wastes offer a promising avenue for sustainable road construction materials.
- Grits can be directly incorporated as aggregates, while dregs need further processing for optimal performance.
- This research contributes to waste valorization and environmentally conscious construction practices.
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