Abstract
A prediction, prompt detection and suitable control of ash deposition on heat transfer surface are one of the most important factors for a stable and highly efficient operation of pulverized coal fired boiler. Several indices based on the coal analysis have been developed for estimating the slagging potential. However, these indices often give misleading results and are somewhat unreliable, because the slagging phenomenon is affected by not only ash behavior in high temperature but also operating conditions, including boiler load, flame length, flue gas temperature and boiler structure. The integrated computer software package named "Idemitsu Coal Assessment System (I-CAS)" was developed to evaluate boiler performances and judge adaptability of each coal. In this system, the gas temperature at several parts in boiler and the melting behavior of ash deposit are calculated to predict ash deposition growth and their location for each coal type and operating condition.
