Exam Question

### (a) Exhaust Gas Economizer (EGE) Definition and Construction
An Exhaust Gas Economizer (EGE), also known as a waste heat recovery boiler, is a heat exchanger that utilizes the thermal energy from the main engine exhaust gases to generate steam or heat thermal oil. Its primary purpose is to improve the overall thermal efficiency of the ship's power plant by recovering waste heat that would otherwise be lost to the atmosphere.
**Principle of Operation:**
The EGE is installed in the main engine exhaust gas uptake. Hot exhaust gases, typically at temperatures between 250°C and 400°C, are directed over banks of tubes containing water. The heat from the gas is transferred to the water, causing it to boil and generate steam.