Bell less top charging system of a blast furnace using PLC and SCADA
Naveenkumar T S, Nirmala C, Jayashree G, Bhanupriya S R
PLC, SCADA,HMI, Relay, Sensors
Blast Furnace is one of the major equipment where the conversion of raw materials like iron ore, Sinter and coke into molten metal (pig iron) takes place. To charge raw material into Blast Furnaces, which are operated at 2kg/cm2 pressure, Bell-less top (BLT) charging system. The Bell less Top Charging System (BTCS) which is a continuous system for charging raw material into a blast furnace for iron making. The valve casing comprising material gate, lower sealing valve and distribution chute assembly is an important unit of the system. This assembly helps to retain the charging material inside the hopper; protect the lower sealing valve during charging; control charging material discharge rate; seal gases of Blast furnace reactions; and seal high counter pressure of furnace. In addition, with leakage of Blast furnace gas being eliminated, safe working conditions have been established, and productivity has increased with downtime of Blast furnace reduced. Good control of the gas flow in the blast furnace ensures greater productivity and a longer life span of the installation.
Various failures of BLT mechanical equipment are studied and noted. Based on this failure analysis Sealing valve failure is taken for further study which is causing highest production loss to the company due to high burden. In proposed work modification of blast furnace bell-less top charging system sealing valve, there is changes in sealing valve opeation which helps in reduce time delay, low maintenance and higher productivity. The modification is based on the alternatives designs suggested to the gland joints and hydraulic circuits and Calculation of forces by the mathematical process
In this project sealing valve and chute can be controlled by using PLC and SCADA, to avoid burden an sealing values, and chute is also controlled for the proper distribution of coke and non-coke material in the furnace