Biodrying – Mechanical treatment and biological drying for the production of a high energy content material

Type of Waste:

The technology is suitable for the treatment of:

    • Mixed municipal solid waste
    • Commercial waste


The process of bio-drying is carried out by forced aeration of the waste, which enables the activation of biochemical reactions that lead to the decomposition of the easily biodegradable fraction. The result of these reactions is the productions of large amount of heat, which enhances the evaporation of the  moisture contained in the waste and the destruction of pathogenic microorganisms.
The dried material produced from biological drying has the following characteristics:

  • It is a stabilized material
  • It does not carry pathogenic microorganisms
  • It does not emit odors
  • It is easily manageable in bales and can be safely stored
  • It has a high energy content

Biological drying takes place either in open tunnel-halls in closed buildings  (in-hall biodrying) or indoors – in bioreactors (garage type). The mechanical treatment of waste prior to biological treatment (eg shredding) allows the preparation of waste  for the process of biodrying. The mechanical post-treatment of the biodried material can upgrade the characteristics of the material to high energy quality fuel.
The product can be utilized for energy production:

  • in Sanitary Landfill Sites of type of closed bioreactor (landfill bioreactor), where the produced biogas is utilized in the best possible way
  • in waste-to-energy  units
  • in the cement industry and other industrial facilities

Case study


The aim of the project is the harmonization with the requirements of national and European legislation, and thus the reduction of waste mass, biodegradable fraction, odors and pathogenic microorganisms placed in landfill site.

The plant consists of a closed industrial building, where all the stages take place. The building is under pressure to eliminate any danger of greenhouse gas emission and dust in the air as well as the waste scattering in the environment. The treatment of waste entering the facility is based on aerobic biological drying technology. At the current stage, the expansion of the unit including the mechanical post-treatment section of the dried material is under study in order to enable the production of solid fuel of high energy content


Project Data:

Incoming waste streamMunicipal solid waste
Amount of incoming waste75.000 tn / yr
Moisture reduction percentage related to the incoming waste mass65%
Final quantity of dried product65% ή 49.000 tn / yr
Quality of dried productMoisture 18%
Calorific value 10.500 kJ/kg
Metal Recovery1.080 tn/yr