Solidification of High Organic Matter Content Sludge by Cement, Lime and Metakaolin

  • Ke Rui
  • Wang Hongxing Hubei Key Laboratory of Disaster Prevention and Mitigation, China Three Gorges University, Yichang, 443002, China
  • Tan Yunzhi
  • Wang Lehua

Abstract

Based on orthogonal experimental design, the key solidification controlling technology of Solidified/Stabilized (S/S) sludge with high total organic content (TOC) by cement, lime and metakaolin was explored by macroscopic tests, chemical components measurements and microscopic analysis. The macroscopic tests show that, the permeability coefficient is mainly affected by initial water content and lime content, and the unconfined compression strength is mainly affected by cement content and lime content. The chemical components measurements show that, the solidification effect of S/S sludge with high TOC is controlled by organic matter consumption, and organic matter consumption is determined by the alkaline environment from the cement and lime hydration reactions, which is mainly affect by the initial water content and lime-metakaolin content ratio. The microscopic analysis results show that, lime consumes parts of organic matter while excess lime produces weak Ca(OH)2 crystal fluffy sheet structure, matakaolin produces pozzolanic reactions with cement and lime instead of soil particles, and consumes the weak Ca(OH)2 crystal fluffy sheet structure produced by superfluous lime. The research has confirmed key controlling points of S/S sludge in case of high TOC, which will provide theoretical guidance and technical support for S/S sludge promotion with high TOC.

Keywords: solidified/stabilized sludge, high total organic content, organic matter consumption, key controlling technology
Published online
2018-10-29
How to Cite
Rui, K., Hongxing, W., Yunzhi, T., & Lehua, W. Solidification of High Organic Matter Content Sludge by Cement, Lime and Metakaolin. Periodica Polytechnica Civil Engineering. https://doi.org/10.3311/PPci.12293
Section
Research Article