A boiler economizer functions to______________________?
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Answer: C. decreases fuel consumption
Explanation
A boiler economizer uses waste exhaust flue gases to preheat incoming feedwater before it enters the drum. Preheating feedwater reduces the amount of thermal energy required from fuel combustion inside the boiler. Lower thermal energy demand directly translates into decreased fuel consumption and improved thermal efficiency. Economizers act as heat exchangers capturing waste thermal energy that would otherwise escape up the chimney. Improving overall thermal plant efficiency lowers operating costs and reduces greenhouse gas emissions. Feedwater preheating also minimizes thermal shock stresses on thick-walled boiler drum components.
Power generation plants install economizers on large utility boilers to maximize fuel economy. Marine steam propulsion systems utilize exhaust gas economizers to conserve heavy fuel oil consumption. Industrial manufacturing facilities rely on waste heat recovery devices to optimize factory energy budgets. Option A steam pressure is regulated by boiler firing rates and turbine throttle valves, not economizers. Option B steam flow rate is determined by consumer demand and feedwater pump speed settings. Option D steam pressure is maintained by system demand rather than the heat exchanger position.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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