Tunisia, Pilot Project on Mechanical Biological Treatment (MBT)

The main objective of this pilot project was to prove MBT (Mechanical-Biological Treatment) being an alternative and suitable solution to landfilling currently practiced in Tunisia. The project consisted in the set-up and operation of a pilot plant for a 2-years period.

First, the waste was characterized allowing to determine different fractions of the waste flow, and in particular the biological fraction.

The following set-up and operation of the pilot plant enabled to identify key parameters for the design of a large-scale installation taking into consideration the operational needs of MBT systems (energy, water, personnel, machinery).

A detailed investigation of the different processes allowed to determine the optimal solution, to set objectives and target values for MBT and to identify the institution and framework for the scientific support and follow up for future MBT projects. The main criteria considered were

• Minimization of odor and leachate emissions 
• Need for water and energy
• Operational needs and system costs caused by the optimization of the biological decomposition of the recyclable fraction
• Production of a secondary fuel (RDF), and
• Evaluation of the opportunity to use the residues of organic matter treated as low-quality compost.

• Waste characterization
• Set-up and operation of a pilot plant with active ventilation, semi-permeable membranes and suitable mechanical engines
• Set-up of an on-site laboratory to follow and adjust the plant parameters (temperatures, aeration)
• Realization of 2 trials of 100 tons of solid waste each: summer and winter trials in order to evaluate the impact of meteorological conditions
• Determination of mass and energy balance
• Laboratory analysis (heavy metals, TOC, AT4) of the compost and leachate produced
• Determination of the best practices for an MBT plant in Tunisia
• Reduction of more than 40% of the volume of waste going to landfill 

Client / Financing Agency

• Agence Nationale de Gestion des Déchets (ANGed), Algeria
• KfW Entwicklungsbank, Germany

Services Period

2013 - 2015