Palm oil mill effluent (POME) elimination has been considered recently as the alternative to expensive biogas recovery to conquer environmental criticisms in the palm oil industry involving the release of biogas (i.e., a primary contributor towards climate change), during POME treatment. With POME elimination and mill-refinery integration considered, the integrated palm oil-based complex (POBC) serves as an appropriate system for sustainable food-energy-water (FEW) nexus evaluations. In this respect, multi-objective optimisation and debottlenecking of POBC has been suggested to address the economic and environmental trade-offs in palm oil mill (POM) for cleaner production. In this study, a stepwise debottlenecking framework was proposed to include previous fuzzy multi-objective optimisation approach and a new debottlenecking method to improve the fuzzy optimal POBC design and evaluate the impact of process on FEW nexus contributions. Each process creates distinctive impact or influence on the POBC performance. Shapley-Shubik Power Index (SSI) has been applied in the notion of power for yes-no voting systems. By evaluating the operate-fail possibilities of internal processes, SSI can be utilised to allocate the power of each process in achieving or failing the POBC performance target, prior to identifying the system bottleneck (SB) in terms of process stage. Therefore, a novel process-level debottlenecking approach with SSI incorporation for a sustainable FEW system was proposed. The SB of greatest impact on overall POBC performance within the fuzzy optimal flowsheet was identified based on SSI allocation and weightage assignment considering decision-maker’s interest in multiple goals. Subsequently, the debottlenecked POBC flowsheet with improvement in SB process parameter was generated subjected to profit maximisation and environmental constraints. In this study, the nut/kernel separation and biomass cogeneration system was identified as the SB of fuzzy optimal POBC. The debottlenecked results show 0.8% and 51% of profit and net energy improvement upon 30% increment of boiler efficiency. The debottlenecked flowsheet is validated in the benefit-to-drawback ratio analysis with a feasible score of 3.9. The POME-eliminated POBC generated via the integrated multi-objective optimisation and debottlenecking framework is applicable for POM retrofit to secure 13 %, 97 % and 47 % of improvements in terms of EP, GHG emissions and WFP compared to the status quo biogas utilisation scenario. The results of the study could aid palm oil holders in real-life planning of budget distribution and maintenance schedule for process stages in the retrofitted POM.

棕榈油厂废液（POME）的消除最近已被认为是昂贵的沼气回收的一种选择，以克服棕榈油行业在POME处理期间涉及释放沼气（即导致气候变化的主要因素）的环境批评。考虑到消除POME和工厂与炼油厂的集成，集成的棕榈油基复合物（POBC）可作为可持续食品，能源，水（FEW）关系评估的合适系统。在这方面，已经提出了POBC的多目标优化和消除瓶颈的建议，以解决棕榈油厂（POM）在清洁生产中的经济和环境折衷问题。在这项研究中，提出了逐步消除瓶颈的框架，该框架包括以前的模糊多目标优化方法和新的消除瓶颈的方法，以改进模糊最优POBC设计并评估过程对FEW关联贡献的影响。每个过程都会对POBC的性能产生不同的影响。Shapley-Shubik权力指数（SSI）已被用于“是/否”投票系统的权力概念。通过评估内部过程的操作失败可能性，可以在确定过程阶段的系统瓶颈（SB）之前，利用SSI分配实现或失败POBC性能目标的每个过程的能力。因此，提出了一种将SSI纳入可持续FEW系统的新型过程级去瓶颈方法。在考虑决策者对多个目标的兴趣的基础上，基于SSI分配和权重分配，确定了模糊最优流程中对POBC总体性能影响最大的SB。随后，在受到利润最大化和环境约束的情况下，生成了具有SB工艺参数改善效果的去瓶颈POBC流程。在这项研究中，坚果/仁分离和生物质热电联产系统被确定为模糊最优POBC的SB。消除瓶颈的结果表明，当锅炉效率提高30％时，利润和净能源改善分别为0.8％和51％。消除瓶颈的流程已在收益与亏损比率分析中得到验证，可行分是3.9。通过集成的多目标优化和消除瓶颈的框架生成的消除POME的POBC适用于POM改造，与目前的沼气利用情景相比，可确保实现EP，GHG排放和WFP方面的13％，97％和47％的改进。研究的结果可以帮助棕榈油持有者在现实生活中计划预算分配和维护计划，以改进POM的过程阶段。