Recent threats to sustainability in the palm oil milling industry such as methane emissions, has impacted the palm oil market negatively. To facilitate methane emission mitigation, most palm oil mills opt for expensive biogas facilities. An alternative solution to this expensive biogas facility, can be an integrated palm oil-based complex (POBC). POBC is proposed to reduce environmental consequences while maximising the palm oil mill profit by integrating it with a palm oil refinery and implementing POME elimination strategy. However, in order to understand the feasibility of the POBC, it is important to identify the most crucial process otherwise known as the anchor process. The anchor process can be determined based on the allocation of incremental economic benefits among the internal processes. On that account, in work proposes a new process-level performance allocation approach based on cooperative game theory to investigate future optimisation strategies for the POBC. Cooperative game theory was previously applied for rationally allocating incremental profits among collaborating parties and determining anchor tenant within an eco-industrial park. In this study, the cooperative game model analyses internal processes instead of collaborating plants to determine the anchor process. The anchor process is critical for defining performance benchmarks for other processes within the POBC. The developed framework is applied consecutively on the given POBC case study based on the presented framework. The optimal results obtained are analysed to determine the anchor process for deciding suitable strategies to improve the overall profitability of POBC.