［Objective］In response to the dual demand for energy-efficient and low-cost thermal insulation technology in the petrochemical industry.［Methods］ A low-cost composite thermal insulation coating was developed by selecting conventional thermal insulation fillers such as hollowglass beads and inorganic thermal insulation powders to partially replace the expensive nano-aerogels.The effect of filler dosage，ratio and pigment-to-binder ratio on the equivalent thermal conductivity and mechanical properties of the coating was investigated. In addition，a comprehensive economic evaluation based on the full life cycle cost and energy saving benefits was carried out in conjunctionwith the actual working conditions of petrochemical projects.［Results］The experimental results showthat the coating exhibits improved key mechanical properties such as adhesion and impact resistancewhile maintaining good thermal insulation performance，and the total cost of production is about 13%lower than that of pure aerogel coatings. The analysis shows that the coating has advantages in initialinvestment，application efficiency and long-term maintenance，and the overall cost over a 15-year service period is 87% of traditional rock wool insulation solutions and 72% of commercially availableaerogel coatings，with significant energy saving and emission reduction benefits.［Conclusion］The study provides theoretical basis and data support for the large-scale application of this type of coatingin the petrochemical field in terms of technical feasibility and economic rationality.