The following table presents stream data for a background process.

(a) Compute MER targets for this process at \(\Delta T_{\text {min }}=20^{\circ} \mathrm{C}\).
(b) Design a HEN to meet the MER targets at \(\Delta T_{\text {min }}=20^{\circ} \mathrm{C}\) with the minimum number of units.
(c) Investigate the feasibility of substituting boiler feed water (BFW) at \(180^{\circ} \mathrm{C}\) to raise steam for part of the cooling water requirement implemented in (b). What is the maximum amount of steam (in MW) that can be raised from this process?
(d) Redesign the HEN, again with the minimum number of units, to meet the MER targets at \(\Delta T_{\text {min }}=20^{\circ} \mathrm{C}\) and at the same time, produce as much \(180^{\circ} \mathrm{C}\) steam as possible.

Stream Feed Temp. (C) Target Temp. (C) C (MW/C) HI 500 100 CI 50 450 1 C2 60 400 C3 40 420 0.75