Residual Treatment Plant (RTP) is a part of Leaching and Purification area in smelters. It is also called Jarosite Precipitation (JP) area.
There are total of 5 Reactors having a capacity of 300 cubic meters each at Zinc Smelter Debari. These reactors are equipped with agitators and steam coil for heating process solution to 100 degree centigrade.
The challenge was that if the agitator of any reactor fails, the steam would continue to flow through control valve to the reactor. As there would be no mixing of solution due to failure of agitator, solution near steam coils would heat rapidly and could lead to explosion of the reactor. The control valve would only be closed manually and that involved great amount of risk as well as process inefficiency.
A team consisting Mr. Vijay Kumar Rana (AM - Process), Mr. Sanjay Kumar (AM - Instrumentation), Mr. Debasis Sahoo (Engineer - Process) and Mr. Sandip Kanani (AM - Mechanical) felt the need for a change in this whole process and automation with steam auto valve cut-off seemed to be the solution.
Once this modification was done, it is ensured that if agitator of any reactor trips, the amperage of the reactor will drop down to no load level and the valve will close automatically preventing the steam entrance into the reactor.
This automation resulted in elimination of major hazard and also eliminated man machine interaction in reactors. It also resulted in power saving and increasing productivity.