COMPARISON OF JET AND SURFACE CONDENSERS

1 Jet Condensers

Advantages

1. Mixing of steam and cooling water is more intimate.
2. Less quantity of circulating water for condensing exhaust steam is required.
3. Condensing plant is simple and less costly.
4. Spare parts required are less.
5. Condensate extraction pump is not needed in barometric jet and ejector condensers.

Disadvantages

1. Condensate is wasted unless cooling water is pure.
2. In the low-level jet condenser, if the condensate extraction pump fails, then the engine would get flooded unless safe guarded.
3. Barometric condenser cost is high due to long piping.
4. There is vacuum loss in barometric condenser due to leakage in long piping.
5. There are limitations of vacuum of up to 650 mm of Hg due to liberation of dissolved gases in cooling water.
6. The air extraction pump requires comparatively high power.

2 Surface Condensers

Advantages

1. Vacuum obtained is comparatively very high, resulting in high efficiency.
2. Condensate can be used directly as boiler feed.
3. There is no need of water treatment plant.
4. It is more suitable for high capacity plants.

Disadvantages

1. It requires more space.
2. Maintenance cost is more.