A decision support system for business development around decentralised waste utilisation in South Africa

Waste management is a growing concern in South Africa mainly due to a lack of infrastructure, skills, and public funding. This paper introduces a novel decision support system (DSS) for decentralised general waste management with a focus on sustainable SMME development. The theoretical framework, methodology, first principle model development and integration are explained as a baseline for the Waste Utilisation Decision Support System (WUDSS). The WUDSS baseline model includes 7 feedstocks, 17 Step 1 processes, 23 Step 2 processes and 24 end-products. In total, the included options allow for more than 600 unique combinations for which all results are calculated and made available as decision support outputs. After defining the WUDSS baseline, a prototype is developed as an output of the paper to evaluate the appropriateness, repeatability, and accuracy of the DSS results. The mass balance and financial verification steps both showed positive results, with 94% of the mass balance results falling within the required specific throughput-based accuracy limits, and 82% of the benchmarked financial results falling within the ranges predicted by the DSS. Finally, to demonstrate the concept, the DSS was applied to a case study for biochar production so that prototype results could be directly compared to measured outcomes. Error-values for the result comparison fell between 0 and 8%, which were found to be well within the ranges required for concept design accuracy. After a final validation step, the WUDSS was found to have met the required specification