<p>In today’s competitive environment, developing an efficient strategic approach to supply chain network design that enhances overall system performance through the optimization of its components is essential. This study investigates an integrated closed-loop supply chain network composed of two green supply chains with heterogeneous products that adopt an interactive approach for the distribution of returned items. In this framework, a portion of returned products from consumers in each supply chain is redirected to its own network, while the remainder is transferred to the partner chain for recycling and reuse in new product manufacturing. The interaction between these chains is limited to this aspect, with other operations remaining independent and non-shared. The fleet is considered heterogeneous, including both green (eco-friendly) and non-green (conventional) vehicles to achieve a more realistic network design. To model this integrated system, a multi-objective mixed nonlinear programming model is developed, aiming to minimize total costs as the economic objective and total emissions as the environmental objective. The model incorporates the Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD) and the cross-docking (CD) concept. The ultimate goal is to optimize critical production system operations, including procurement, manufacturing, and distribution while considering green aspects. The proposed model is implemented on a small scale and further solved for larger instances using three metaheuristic algorithms: NSGA-II, NRGA, and MOPSO. Results demonstrate that interactive approaches, alongside simultaneous pickup and delivery and cross-docking concepts, significantly reduce total costs and environmental impacts of supply chain networks.</p>