Introduction to Steam Distribution
The steam distribution network comprises of pipelines and accessories that connect the steam boiler to the process equipment. The key objective of the distribution network is to transport steam as efficiently as possible, in the required quantity and at the right quality from the steam boiler to the point of use in the process. In practical settings, plants face several issues due to deficiencies in the distribution network.
| Issues | Possible Causes |
|---|---|
| Pressure drop or steam starvation | Undersized steam lines |
| Frequent leakages from flanges, gasket failures or pipeline leakages | Condensate accumulation in the lines on account of – Wet steam – Necessary pipeline slope not provided – Incorrect drain pockets – Sagging of the pipelines due to incorrect/ inadequate supports – Steam traps not installed at desired locations – Water logged /blocked /isolated mainline traps |
| Displacement of the pipelines | – Incorrect/no provision for pipeline expansions – Incorrect piping supports |
| Higher batch times in the process | Presence of air / air-steam mixture in the system |
| 7-10% gap between steam generation and consumption / unaccounted distribution loss | – High radiation losses – Leaking steam traps – Direct steam leaks |
Table: Common issues in steam distribution and their possible causes
These issues adversely impact the plant’s performance on Product Quality, Productivity, Energy Conservation, Safety, Uptime and Sustainability.
Optimising the distribution network involves addressing four key aspects:
- Supplying the right quantity of steam to the process
- Ensuring steam quality i.e. the steam is dry, clean and free from air
- Ensuring that the distribution losses do not exceed 3% of steam generation
- Making sure that the network is safe and easy to operate and maintain