Thermodynamic Analysis And Energy Saving Research On SKS Lead Smelting Process Of Oxygen Bottom Blown Furnace

The bottom-blowing Furnace is an indispensable equipment to SKS lead smelting process, energy-saving work of the enterprises by using SKS lead-smelting process must be carried out on the bottom-blowing Furnace.Therefore, it is significant to determine the weak links in energy utilization and energy losses'reasons, positions and values by applying thermodynamic analysis on a lead smelting process of the oxygen bottom-blown furnace, and then to propose some energy saving measures for reducing energy consumption.In the paper, the chemical reaction mechanisms of the oxygen bottom blown furnace are analyzed. Based on the thermodynamic and dynamic principles, a metallurgical model and a thermal equilibrium model of the system are established, the main factors affecting on the thermal efficiency are analyed. The results show that:without any gas recovery and waste heat utilization equipment, the thermal efficiency of the bottom-blowing furnace is 34.59%, the heat loss of high lead slag is 9871.46MJ/h, account for 19.31% of the total heat loss; the heat loss of flue gas is 30153.23 MJ/h, account for 58.97% of the total heat loss. If some measures to reduce the heat loss are taken, the thermal efficiency can be improved by46percentage point; if recycles the heat loss, the standard coal can be saved by about 1.366t per hour.Secondly, a exergy model of the system is established according to the energy transfer, conversion and dissipation mechanism. Some indices, such as exergy efficiency and exergy loss etc., are obtained through the exergy analysis. The results show that the exergy efficiency of the SKS bottom-blown furnace is only 25.28% if there is no any gas recovery and waste heat utilization equipment. The total exergy loss includes exergy loss caused by exhaust smoke, physical exergy loss of the output production and internal exergy loss due to irreversibility factors such as chemical reaction, etc, accounts for 74.72%. The total exergy flow of 152727.52 MJ/h is much more than the total heat flow of 78172.82 MJ/h, which shows that the essence indwelled in material and energy flow of the SKS bottom-blowing furnace is better manifested through exergy analysis than through energy conversation analysis. At last,based on the overall thorough exergy analysis of the SKS lead smelting system, the energy saving measures were proposed and discussed, which are strengthen the recovery and the utilization of waste energy of the high lead slag and gas.