Throughout the palm oil milling process, fresh fruit bunches are converted into crude palm oil and a large amount of palm-based biomasses are produced as byproducts. Processes that convert palm-based biomass (e.g., empty fruit bunches, palm oil mill effluent, etc.) into value added products via single conversion technology (i.e., thermal, biological, and physical conversion technologies) are well established. However, integrating multiple conversion technologies to convert palm-based biomasses into value-added palm green products (e.g., biofuels, biochemicals) has not been studied. In this work, a conceptual zone of integrated palm oil processing complex (POPC) that is owned by single owner is introduced to fully utilize palm-based biomasses for value-added palm green product production and heat and power generation. In this work, integrated POPC is defined as a complex that integrates palm oil mill (POM), palm oil refinery (POR), palm oil-based biorefinery (POB), and combined heat power (CHP) at the same site. A systematic generic approach for synthesis and optimization of integrated POPC to achieve maximum economic performance is developed and presented in Part 1 of this series. The optimized network configuration that achieves the targets can also be determined. Meanwhile, the synthesis and optimization of integrated POPC that has multiple owners of those processing facilities is further analyzed based on industrial symbiosis concept and will be presented in Part 2 of this series.