pinch analysis heat exchanger problem table

The improvement of design can be realised by Appropriate Placement and Plus/Minus principle. Find the trade-off between utility consumption, heat exchange area and number of units. Reduce redundant elements, as small heat exchangers, or small split streams. Determine matches in subsystems and generate alternatives. Synthesis of heat exchanger network (HEN) for minimum energy requirements and maximum heat recovery. ⊙ Number of units and heat exchange area. Set a reference basis for energy integration, namely: 2 The synthesis of a Heat Exchanger Network consists of three main activities: 1 a. This feature helps the selection and placement of utilities, as well as the identification of the potential process/process matches. Another diagram, Grand Composite Curve (GCC) allows the visualisation of the excess heat between hot and cold streams. The counter-current heat flow of the streams selected for integration may be represented by means of Composite Curves (CC). If not, stream segmentation is necessary 7. The key computational assumption in Pinch Point Analysis is constant CP on the interval where the streams are matched. Stream selection and data extraction are essential in Pinch Analysis for effective heat integration. The result is that heat recovery problem becomes an optimisation of both energy and capital costs, constraint by a minimum temperature approach in designing the heat exchangers 5. The operation will be paid by supplementary energetic consumption, which has to be optimised against the reduction in capital costs. When the capital cost is high, it might be necessary to remove the Pinch constraint in order to reduce the number of units. The partition of the original problem in subsystems may introduce redundancy in the number of heat exchangers. No design can achieve MER if there is a cross-pinch heat transfer. For given ΔT min the hot and cold utility consumption identified so far becomes Minimum Energy Requirements (MER). Above the Pinch there is need only for hot utility, while below the Pinch only cold utility is necessary. Consequently, the system can be split into two stand-alone subsystems, above and below the Pinch. This tool allows the identifications of the Pinch, as well as of targets for hot and cold utilities. The fundamental computational tool is the Problem Table algorithm. The Pinch is characterised by a minimum temperature difference ΔT min between hot and cold streams and designates the location where the heat recovery is the most constraint. Pinch Point Analysis is a systematic process design methodology consisting of a number of concepts and techniques that ensure an optimal use of energy.

Pinch analysis heat exchanger problem table