List of top Plant Design and Economics Questions on Principles of process economics asked in GATE Chemical Engineering

Consider the process in the figure for manufacturing \( B \). The feed to the process is 90 mol% \( A \) and a close-boiling inert component \( I \). At a particular steady-state:
- \( B \) product rate is 100 kmol \(h^{-1}\)
- Single-pass conversion of \( A \) in the reactor is 50%
- Recycle-to-purge stream flow ratio is 10
The flow rate of \( A \) in the purge stream in kmol h^-1, rounded off to 1 decimal place, is ___________ 

The capital cost of a distillation column is Rs. 90 lakhs. The cost is to be fully depreciated (salvage value is zero) using the double-declining balance method over 10 years. At the end of two years of continuous operation, the book-value of the column, in lakhs of rupees, rounded off to 1 decimal place, is___