Total site material recycling network design and headers targeting framework with minimal cross-plant source transfer

Abstract

Proper resources recycle or reuse planning helps the industrial sites to reduce reliance on raw resources. There are a lot of previous researches that had applied the Pinch Analysis on the resources recycling problem. However, there is not much work completed on targeting the materials headers or mains from the sources of the plants. This work extends the Material Recovery Pinch Diagram to provide an insightful yet straightforward approach to targeting the material headers/mains with minimum fresh resource consumption (e.g. water, hydrogen or CO2) with single quality. The flowrates and the concentration of the exchanged streams in the material headers, as well as the minimum number of headers, can be targeted using a Pinch-based strategy, which can be applied at either process or Total Site scale. This study also proposes a novel algorithm to minimise the cross-plant material source transfer for the Total Site material network with header/mains design while ensuring the overall minimum fresh resource target is satisfied. A Source Transfer Diagram is proposed to identify optimal reuse opportunities of the purged sources from individual plants. A case study is used to demonstrate the proposed framework, comparing results obtained using direct integration and centralised headers. The benefits of this framework are two-fold. It provides the minimum resource consumption rates for the overall network, and it also enables the network and mains/header design through graphical visualisation, which is a non-linear problem. The graphical interface allows users to explore different source mixing options from individual plants while ensuring the number of headers, resource consumptions, and cross-plant source transfer are minimal.