Heating Furnace Wall Dissipation Calculation And Structural Optimization

This paper is on the basis of deeply understanding on the heating furnace, taking the No. 4 furnace of the Wuhan Iron and Steel Group as an example, proposes a simple and quick calculation method of the furnace wall heat dissipation. Taking wall heat transfer as a big flat steady state heat conduction model, through the method of searching calculation domain to estimate the furnace wall heat dissipation, and calculate the analog temperature on specified point by using the method of numerical simulation, compared with the measured temperature, the value difference is minimized. At the same time the convective heat transfer was used on the furnace flue gas side to calculate the wall heat flux, compared with the result of heat conduction mode. The above results show that the simple and fast calculation method proposed above is feasible and valid.On the basis of the calculation results, the author made the furnace wall heat energy saving analysis and found out the most energy saving prospect of furnace. Analysis results showed that heat loss on the top account for 58.21% of the total furnace wall heat loss, was much bigger than the furnace heat release proportion on the bottom and the side. For the higher temperature of heating and soaking, heat losses accounted for 31.48% and 30.95% respectively, indicating that the second heating section on the top can appropriately adjust the thickness of the insulation material to further reduce the heat loss.The finite element analysis was conducted on the second heating section of the top the furnace wall structure of the optimal solution was observed. By dividing the most energy saving potential second-heating section on the top into nine combinations of different material thickness according to the research object, respectively conducted the finite element analysis on the nine schemes. In combination with heat loss calculation, heat storage calculation and cost calculation, the fourth scheme is the most economic, energy saving, and the outer wall temperature is within the scope of technical requirements. At the same time, the results of the analysis showed that the relationship between the heat loss, storage loss, the outer wall temperature, the average temperature and the thickness of different materials, provided referential basis for the reasonable arrangement of insulation materials.From analyzing the mutual influence between the wall thermal insulation material and the furnace operation, the author put forward proposals for the decreasing of the corresponding wall heat dissipation. The main components of the furnace wall heat preservation material is aluminum silicate fiber, which can easily crystallize under high temperature, leads to thermal insulation material’s easily aging and harden in the long-term using process. At the same time mechanical action and flame scour damage in the process of heating furnace operation and so on are easy to make the heat preservation material thinning, can lead heat preservation performance degradation. The weakening of heat preservation material will lead to the increase of the furnace wall heat loss, to further increase the flue gas leakage and the workshop environment thermal pollution. Based on this, the author puts forward four Suggestions as follows.1) Reduce the adjust delay of temperature control, create a set of slab temperature real-time monitoring software programming.2) Dust removal furnace wall on a regular basis.3) Without affecting the quality of the slab rolling, insulation material can be appropriately replaced. 4) The dome of waste heat recovery of furnace wall is used.