Root cause failure analysis of a division wall superheater tube of a coal-fired power station

Determination of Trace Iron in the Boiler Water Used in Power Generation Plants by Solid-phase Spectrophotometry

“…To a 50-cm 3 boiler water sample, 2.5 cm 3 of (1+1) hydrochloric acid was added, and then the solution was allowed to stand in boiling water for 30 min to digest the particulate matter containing iron. The water sample was then allowed to cool to room temperature, and 1 cm 3 of the hydroxylammonium chloride solution, 2 cm 3 of the TPTZ solution, 3.5 cm 3 of the formic acid-ammonia buffer solution, and 0.08 cm 3 of Muromac 50W-X2 resin (Muromachi Technos) were added in this order. Next, the mixture was stirred for 30 min at 25 C in the thermostated bath.…”

“…A coloring reagent TPTZ solution was prepared by dissolving 0.32 g TPTZ (Wako, Tokyo, Japan) in 1 cm 3 (1+1) hydrochloric acid, and then diluted to 500 cm 3 with water. A reducing agent (hydroxylammonium chloride) solution (10%) was made by dissolving 10 g of hydroxylammonium chloride (Wako) in water and made up to 100 cm 3 . The Muromac 50W-X2 cation exchanger (100 -200 mesh) was purchased from Muromachi Technos, Tokyo, Japan.…”

“…1 Tube corrosion is known to be the main cause of boiler failure, and at its worst, a single corrosion failure can make a plant inoperable. 1,2 The total cost of boiler tube failures in power plants is estimated to be about 5 billion dollars a year, 3 and accidents temporarily interrupt power supply to tens of thousands of consumers. Scale deposits in boiler systems are another main concern since they significantly decrease energy efficiency.…”

“…8 Regarding the concentration, the SPS efficiency is significantly greater than that of evaporation concentration. For example, in the solution spectrometric method, an 800-cm 3 boiler water sample has to be evaporated/concentrated to 50 cm 3 by heating for 4 -5 h to obtain a measurable iron concentration. 9 However, in the present SPS method for iron determination, a 0.08 cm 3 cation exchanger is added to a 50-cm 3 boiler water sample, and mixed for 30 min to adsorb/concentrate the colored analyte on the solid beads, resulting in a 625 times concentration of the target analyte in 30 min without any other procedure.…”

RAM investigation of coal-fired thermal power plants: A case study

“…Liwei et al (2005) proposed a new method and algorithm for functional reliability simulation for a steam-turbine's behaviour and established a degeneration model based on the laws of the steam-turbine. Rahman et al (2010) worked on root cause failure analysis of a division wall superheater tube (super alloy Inconel ® 800) of a coal-fired power station in Kapar Power Station, Malaysia. Purbolaksono et al (2010) had undergone failure case studies of SA213-T22 steel tubes of the reheater and superheater of boiler using computer simulations.…”