Boiler house Heat recovery systems
2
How to size Use the chart below to select the appropriate flash vessel. It is necessary to know the pressure on the steam traps or boiler pressure in the case of blowdown heat recovery, the flash steam pressure (desired or existing), and the condensate or blowdown flowrate. Example 1: (solid lines) A boiler plant operating at 12 bar g has a TDS control blowdown flowrate of 2 500 kg/h (3 boilers at 833 kg/h each). The flash steam from the blowdown is to be added to the low pressure steam system operating at 1 bar g. 1. From boiler pressure move horizontally to flash steam pressure - A 2. Drop vertically to blowdown flowrate in kg / h - B 3. Follow curve to right-hand scale and across to same flash pressure - C 4. Move upwards to flash vessel size. Select flash vessel - in this case an FV8 is required.
Example 2: (dotted lines) A plant operating on steam at 11 bar g condenses 4 000 kg/h of steam. Flash is to be recovered at 0.5 bar g. 1. From pressure on steam traps move horizontally to flash steam pressure - A1 2. Drop vertically to condensate flowrate in kg/h - B1 3. Follow curve to right hand scale and across to same flash pressure - C1 4. Move upwards to flash vessel size. Select flash vessel - in this case an FV12 is required.
2.8 15
Flash steam pressure bar g
Example 1 Example 2
Flash vessel size
TI-P404-03 EMM Issue 11
Page 3 of 4
FV Flash Vessel
Powered by FlippingBook