Proceedings

The cost of energy in thermal drying processes represents more than 50% of the total costs in thermal sludge processes. The
price of fossil fuels has increased considerably over recent years, and future trend prospects look increasingly worse.
Renewable energy production systems, such as wind-driven generators, solar panels, biomass, etc, pose a problem in terms
of availability. This requires a compatible, flexible and integrated technology for thermal drying that offsets this partial use, in
order to attain an operating range that is economical, such as heat pump technology. This article includes a technicaleconomic analysis of various combinations for the use of heat pumps offset by renewable energy for thermal sludge drying.

KEY WORDS
Fuels, heat pump, Kyoto protocol, renewable energy, sludge, thermal drying