A Practical Example for Generating Steam Balance

FIGURE 16.7. Step 3b Converged steam balance based on DA steam iterations. 

High-pressure steam is generated from three on-purpose boilers, together with the waste heat boiler (H-9001) in the hydrogen plant and the convection section of a 

FIGURE 16.8. A practical example of the steam system with missing flows. 

This imbalance is caused by metering error and corresponds to 5% of total HP steam input, which is not acceptable compared with the best practice guideline suggesting 3% or less. We will discuss this later for identifying the root causes of the imbalance and to close the balance with higher accuracy. 

For the MP header, steam input comes from the process-fired heater F-5001 where the radiation section is used for process feed heating, while the convection section for MP steam generation. MP steam is also made from the extraction of CT-1401 turbine, the HP letdown, and two WHBs. On the other hand, MP steam is used as column reboiling and stripping as well as in the steam turbines and MP letdown. CT-1601 turbines run a compressor and boiler PTs include four small turbines used for running a boiler water circulation pump and three AD fans. Since MP letdown is not measured, it is unknown and to be determined together with the MP imbalance. The MP imbalance includes metering error, steam losses due to steam traps, leaks, and so on. Table 16.10 shows the balance for the MP header. 

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