Feed Water Heaters Performance Indicators  and Characteristics on the 405MW   Coal-Thermal Power Plant

Jameson R. Almedilla; Leonel L. Pabilona; Eliseo P. . Villanueva

Jameson R. Almedilla College of Engineering and Architecture University of Science and Technology of Southern Philippines – Cagayan de Oro Cagayan de Oro City, 9000 Philippines
Leonel L. Pabilona College of Engineering and Architecture University of Science and Technology of Southern Philippines – Cagayan de Oro Cagayan de Oro City, 9000 Philippines
Eliseo P. . Villanueva College of Engineering Mindanao State University – Iligan Institute of Technology Iligan City, 9200 Philippines

Keywords: terminal temperature difference, drain cooler approach, temperature rise

Abstract

The coal-fired thermal power plant with a capacity of 3x135 MW gross or a total of 405 MW is composed of two high-pressure, one deaerator-heater and four lowpressure feed water heaters arranged in cascading stages on each of the three units. The objectives of the study are to determine the performance of these feed water heaters, both HP and LP, using the American Society of Mechanical Engineers Performance Test Code (ASME PTC) 12.1 and Heat Exchange Institute (HEI) Inc. procedures with engineering report and comparative discussions. Performance indicators such as terminal temperature difference (TTD), drain cooler approach (DCA) and temperature rise (TR) across heater were used to determine each unit’s feed water heater system performance. The results showed that the high-pressure feed water heaters (HPH) were significantly more efficient compared to the low-pressure feed water heaters (LPH). An alarming off-design condition was encountered by the last stage heater, LPH7, in unit one where it showed a lower TR of around 2.95°C and the highest TTD of 49.86ºC. Thus, the results of the test showed that unit one and two has some problem on its last stage heater while unit three was performing better than the other two units. Based on the evaluation of the results, the last stage heaters were recommended to be evaluated for further analysis to prevent failure of equipment and these need necessary improvements. Generally, heaters are part of power station forthe increase of cycle efficiency.