New Estimation Method of Fouling for the Low-Rank Coals: Sintering Factor
(Room Garuda 10B, 1st Floor)
19 Sep 18
4:30 PM
-
6:00 PM
Tracks:
TRACK C - Optimizing Plant Operation
Although the low rank coals such as sub-bituminous and lignite coals are getting more and more popular in coal firing power stations in the world, it is still difficult to estimate the precise slagging and fouling characteristics, some coals sometimes caused to lower unit availability and unit efficiency drop. Since current criteria for ash slagging/ fouling are mostly established for US and/or European coals, Australian coals have provided other indices for coal slagging. As well, some of the Indonesian sub-bituminous coals could not apply to the popular indices related to slagging/fouling. In fact, coal firing boilers in Malaysia sometimes encountered the severe slagging/fouling problem which caused tube leakages and/or required to unit shut down for clearing the ash/slag from the boiler. As of the practical ways for precisely evaluating the slagging and fouling potential, IHI and IIC have newly developed SINTERING FACTOR, which could apply to any of bituminous and sub-bituminous coals, and tested more than 30 kinds of Indonesian bituminous/sub-bituminous coals. SINTERING FACTOR could then well-evaluate the DEGREE of slagging/fouling characteristics for coals which are mostly difficult to evaluate by the popular slagging/fouling indices. This paper describes the methodology of SINTERING FACTOR and its application to coals involving Indonesian bituminous/sub-bituminous coals. SINTERING FACTOR has been also related to the boiler operation, influencing to the ash/slag deposition at the higher and lower temperature area, resulting into boiler flue gas temperature. We also discuss ash chemistry through the simulation by FactSage, comparing SINTERING FACTOR with the fraction of liquid phase of ash coming from Ash Chemistry. We also explain the multiple regression analysis from the coal ash data, relating SINTERING FACTOR with ash component and conventional slagging/fouling indices, which will provide which factors relate more with the actual ash sintering behavior.