What is the primary purpose of incorporating an economizer in boiler systems _______________________?
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Answer: A. increase thermal efficiency of boiler
Explanation
An economizer preheats boiler feed water using waste heat from exhaust flue gases, which directly increases thermal efficiency. Recovering thermal energy that would otherwise escape up the chimney reduces the total fuel required to generate steam. This heat exchanger acts as a vital energy-saving device in modern high-capacity industrial steam power plant designs. Boiler economizers are placed in the exhaust flue gas path to transfer residual heat into incoming cold feed water. Thermal efficiency measures the ratio of useful energy output to total chemical energy input supplied by the boiler fuel. Preheating feed water also reduces thermal shock stresses inside the main boiler drum by narrowing temperature differentials.
Economizing on fuel is a direct economic outcome rather than the primary thermodynamic mechanism increasing boiler thermal efficiency. Extracting heat from flue gases describes the method used, but increasing boiler efficiency is the overarching performance goal. Heating feed water using bled steam describes feed water heaters, whereas economizers utilize hot exhaust flue gases.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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