Design And Application Of Control System For Large Titanium Slag Electric Furnace

Titanium alloys are widely used in aviation,shipbuilding,military,medical equipment and other fields because of their light texture and high strength.The reserves of titanium resources in China are large,mainly in the form of titanium iron ores.Titaniferous rock has low grade and high content of impurities.It is necessary to remove impurities and rich titanium to produce titanium slag before it can be used as raw materials for producing high quality titanium dioxide and sponge titanium.At present,the production of titanium slag in our country mostly adopts the traditional small open smelting furnace,which has low degree of automation,high energy consumption,environmental pollution,and can not support and meet the needs of the titanium industry and national economic development.Therefore,the development of large-scale and intelligent production of titanium slag will be the future development trend.Panzhihua Iron and Steel Co.has introduced and developed large-scale titanium slag electric furnace production technology.The project is divided into two phases.One phase is to build a 25.5 MVA electric furnace with an annual output of 60 kt/a,and the second phase is to build two 25.5 MVA electric furnaces with a single output of 60 kt/a.During the operation of the first-stage electric furnace,there are still some shortcomings,such as low precision of electrode control,large unbalance of three power items,low utilization rate of electric energy,inability to realize program control of furnace pressure,and manual participation in the distribution process.Based on the second stage project of Panzhihua Iron and Steel Group Co.,Ltd.,this paper designs a practical and stable automatic control system for large-scale titanium slag electric furnace according to the problems existing in the operation of the first stage electric furnace and the development of the current industrial control technology.For the four subsystems of electrode automatic lifting control,furnace pressure automatic control,automatic feeding control and auxiliary facilities related control,the paper designs algorithm model,,selects Siemens PLC as the control equipment,and uses SIMATIC WinCC to design man-machine interaction interface.A set of automatic control system for large-scale titanium slag electric furnace is established.In the process of production,relevant parameters can be inputted through friendly man-machine interface to realize the automatic control of smelting process.It can effectively reduce the unbalance of three-phase power input,improve theefficiency of power input,reduce the safety risk of smelting process,and realize the purpose of reducing production costs and improving economic benefits.