A study on the four-party evolutionary game of collaborative carbon emission reduction in the petrochemical industry

Against the dual backdrop of domestic green transformation and international carbon emission reduction constraints, this paper addresses the challenge of synergistic carbon governance in the petrochemical industry. Grounded in the industry’s characteristics of long facility service life, high transformation costs, and strong policy dependence, it focuses on the interest conflicts among four parties—the central government, local governments, petrochemical enterprises, and third-party regulatory agencies—and develops a four-party evolutionary game model. Through local stability analysis and numerical simulation, the stability conditions and evolutionary trends of the four parties’ strategy choices are systematically examined. The results indicate that: (1) Raising the central government’s penalty intensity significantly shortens the decision-making time of the central government, petrochemical enterprises, and third-party agencies, yet prolongs the strategy evolution time of local governments; (2) As the central government’s subsidy coefficient increases, the central government’s strategy exhibits persistent fluctuation within the 0–1 interval and fails to converge to a steady state, while the decision-making time of petrochemical enterprises is markedly shortened, with the evolutionary trajectories of local governments and third-party agencies showing no significant change; (3) Strengthening local governments’ penalty intensity effectively accelerates the decision-making of local governments and petrochemical enterprises, whereas the evolutionary trajectories of the central government and third-party agencies remain largely unaffected; (4) Increasing local governments’ subsidy coefficient slows the evolution of local governments toward the proactive emission-reduction governance strategy, but effectively drives petrochemical enterprises to actively evolve toward proactive carbon reduction strategies. These findings offer theoretical support and practical implications for improving the multi-agent collaborative governance mechanism of carbon reduction in the petrochemical industry, assisting governments at all levels in formulating differentiated carbon regulation policies with precision, and promoting the green and low-carbon transformation of the petrochemical sector.