Pinch design energy targets

In other words, to achieve the energy target set by the composite curves, the designer must not transfer heat across the pinch by... 

Given the stream data provided in Table 6.3, identify the energy targets and pinch temperatures. Design a HEN that achieves the maximum energy recovery. 

The pinch analysis method is a simple thermodynamically based method that is widely used to provide the energy targets for the HEN designs of the examined process. The design of the HEN is classified as a sub-problem of the overall process synthesis and design problem where its combinatorial procedure for matching the process streams are well covered in literature. 

Figure 16.23a shows the complete design, achieving maximum energy recovery in one more unit than the target minimum due to the inability to tick off streams below the pinch. 

When designing a HEN to meet its MER targets, stream splitting must be employed if (a) the number of hot streams at the pinch, on the cold side, is less than the number of cold streams or (b) the number of cold streams at the pinch, on the hot side, is less than the number of hot streams. In this way, parallel pairings that fully exploit the temperature differences between energy sources and sinks are possible. Moreover, stream splitting helps to reduce... 

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