The influence of operating experiences in the design of the IVAR thermal drying plant expansion in Stavanger, Norway

摘要

The Regional Wastewater Treatment Plant of North Jaeren (IVAR IKS) serves the Stavanger conurbation with a population equivalence of 240,000. The site was the first in Norway to operate a thermal drying and a pelletising plant for municipal sludge. Since the start up in 1992, IVAR has encountered most of the operational problems typically associated with thermal drying processes. Considerable modifications have been made and lessons learnt resulting in the plant being one of the few thermal drying facilities in Norway which continues to operate successfully. In general, thermal drying is often considered as a costly, energy demanding and complex process requiring careful attention to safety aspects such as risks of self-combustion, fires and dust explosions. The paper presents general considerations of operating experiences influencing the procurement and design stage of the new extended IVAR thermal drying plant. Furthermore, topical issues important for resolution of thermal drying problems are also discussed. Mass and energy balances for the Stavanger plant are presented.