Annex X: Energy Efficient Drying and Dewatering Technologies

This Annex was finished in 2011. The six technical reports delivered are listed and available for download at the bottom of this page.

Technical Background

Solids drying can be found in many areas of human activities, from the household to the process industry. In many cases drying is not only the final step in the total dewatering process but also the final step in a production process.

In the drying process the energy use and costs can be reduced by a number of methods:

  • optimize the process or change to a more energy efficient process such as drying in superheated steam
  • recover a larger part of the secondary energy for low-temperature heating within the process system or deliver it externally to district heating networks
  • replace expensive primary energy sources with less expensive such as replacing oil with biofuels
  • switch to energy sources which have less environmental impact reducing the costs for pollution abatement techniques and emission taxes for carbon dioxide and possibly resulting in green certificates for produced renewable electricity

Description of Annex

Separation processes such as distillation, evaporation and drying, are used in the production of all kind of different products and the energy use in this sector constitutes a major part of the total industrial energy use.

The activity in Annex X has focused on knowledge transfer and deployment of information between the members of the IETS countries.

The need for enhanced assessment of key energy-related drying and dewatering technologies highlights the need for dissemination of results from different areas and different countries. Some of the objectives of this Annex has been to highlight ongoing research projects in the drying area, compile relevant information about legislation and how to increase the dry matter content.

The objectives of this Annex has been the following:

  1. Make available information about on-going research projects in the drying area, present a survey of the energy used for drying in the participating countries and establish methods for benchmarking of different dryers.
  2. Compile the relevant legislation for drying of sludges, biowastes and solid biofuels as well compare a number of methods for drying of these products.
  3. Compile available information about how the dry matter content can be increased for mechanical dewatering of sludges, biowastes and solid biofuels.

Annex Manager

Prof. Stig Stenström, Lund Institute of Technology, Department of Chemical Engineering, Sweden

Annex Deliveries
Drying and Dewatering of Sludge – Summary of Papers Presented at ECSM´08
Compiled by Ola Jonassen, VVS, Norplan AS, Norway; Angelique Leonard & Michel Crine, Université de Liège, Belgium; Stig Stenström, Lund University, Sweden.
Compiled by Stig Stenström, Lund University, Sweden
Compiled by Stig Stenström, Lund University, Sweden
Compiled by Odilio Alves-Filho, NTNU, Norway
Compiled by Ola Jonassen, VVS Norrplan, Norway
Compiled by Stig Stenström, Lund University, Sweden