Asian Journal of Pure and Applied Mathematics

Multi-Component Ternary Solidification /Stabilization System Based on Gibbs-Roozeboom Triangular Model and the System Operationalized as Unit Processes in a Process Flow Diagram

Duke Orata *

Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya.

*Author to whom correspondence should be addressed.

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Abstract

In this paper we discuss a novel multi-component ternary solidification/stabilization system for a simulated leachate concentrate contaminant. The multi-component ternary system components are bentonite, water hyacinth and cement as host matrices.
In this multicomponent system the solidification/stabilization unit is shown to be effective in sequestering Cr (VI) and all the other metal cations investigated and also toluene in the organic simulation liquid.
The Gibbs-Roozeboom triangular diagram for multicomponent systems has been used to establish the final composition of a mixture of the constituent host matrices in the ternary stabilization/solidification unit.
Heavy metal cations Pb²⁺,Cr(VI), Cu²⁺, Zn²⁺, Ni²⁺, Mn²⁺ and organic compound toluene in a simulation leachate concentrate contaminant have been sequestered effectively by the multicomponent ternary solidification/stabilization unit, through physical and chemical adsorption, ion exchange, ultra-filtration by nanotubes and deliberate geometrical design of the ternary solidification/stabilization unit to influence the hydraulic conductivity of the simulation leachate liquid in the system. 
 A process flow diagram has been proposed for the ternary solidification/stabilization system where the host matrices are considered as unit processes.
The bentonite in the process flow diagram acts as a tray column, water hyacinth as a tubular reactor and Portland cement as a packed column or fixed bed reactor.
In the coiled multicomponent ternary system configuration, the coiled host matrix represents   a serpentine tube reactor.
The unit processes in the solidification/stabilization ternary system can therefore be optimized for increased operational efficiency by upscaling/and or realignment of the unit processes in the multicomponent ternary solidification/stabilization unit.
Variation of pH of the simulation leachate concentrate was observed not to affect the stabilization of the heavy metal cations studied.

 

Keywords: Sedimentary model, stabilization, solidification technology, leachate concentrate

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