The ZGM123G-II medium-speed vertical coal mill system matched with a certain 6 200t/d clinker production line had long experienced problems such as coarse pulverized coal fineness and high power consumption. Through the upgrading of the grinding area by expanding the diameter of the grinding track of the table and the size of the grinding roller, and upgrading the grinding curve. Apply the new type of high-efficiency and low-resistance separator, optimize the rotor seal design. By optimizing and upgrading the air ring, the gas flow field and heat exchange inside the mill can be improved. Change the control mode of the hydraulic system to enable the central control operation to adjust the grinding pressure at any time, the fineness of pulverization coal R80μm decreased from 11% to <6%. The power consumption of the main motor of the vertical mill decreased from 15.5kW·h/t to 11.0kW·h/t, and the system power consumption  decreased from 28.7kW·h/t to 24.3kW·h/t. The payback period of the project investment is less than two years. It saves CNY 974 000 yuan in electricity fees annually, achieving remarkable energy-saving and consumption-reducing effects.