What is the function of the steam injector in low-capacity boilers____________________?
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Answer: C. pump water, similar to boiler feed pump
Explanation
A steam injector uses high-velocity steam expansion to entrain and pump feed water into low-capacity boilers, acting as a feed pump. It converts thermal energy from steam into kinetic energy, creating a low-pressure zone that draws in water and forces it against boiler pressure. This compact device eliminates the need for complex mechanical water pumps in small industrial steam generation plants. Steam injectors operate on the Bernoulli principle and momentum transfer between high-speed steam and liquid water jets. They serve as reliable, non-moving-part mechanical pumps capable of feeding high-pressure water using boiler steam. Low-capacity boilers benefit from the simplicity, self-priming capability, and integrated water preheating provided by injectors.
Steam ejectors are sometimes used to create vacuum, but boiler injectors are specifically designed for pumping feed water. Injecting chemical treatment solutions into feed pumps is handled by small chemical dosing pumps rather than main steam injectors. Adding makeup water is a system-level function, whereas the injector acts primarily as a high-pressure water delivery pump.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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