MERCURY RETORTMENT SYSTEM
This system is used where the mercury retortment in form of liquid and gas is needed in gold and silver plants.
PLC, HMI, programming and automation cabinet is manifactured by our company.
The system includes close circuit temperature and pressure controls.
The process is adjusted step by step according to the chemical properties of gold or silver.
The systems’ instrumentation, motors and system parameters are displayed and controlled on the HMI panel.
SYSTEM INSTRUMENTATION AND CONTROLS
- Cooler: Used for cooling the vapor and liquid
- Vacuum Pump: Provides vacuum pressure to pull mercury and vapor
- Temperature Sensor: Furnace temperature is read by thormocouple
- Flow Sensor: Flow rate control
- Pressure Sensor: Vacuum pressure and differential preasure is checked
- Solid State Relay: Furnace heaters are controlled via PID
- Pneumatic Proportional Valve: Pressure is controlled via PID
HEATING AND COOLING PARAMETERS
The heating, cooling duration of gold or silver inside the furnace and temperature of furnace is crucial. Thus perfect control is needed for the system.
The furnace is heated and cooled in 6 steps.
1- First set temperature is freely reached.
2- The furnace temperature is holded for determinated period. If the furnace pressure is on the desired level at the end of the period, system moves to the third step. If not system doesn’t move on to the third step.
3- Adjusted temperature increases by the temperature/time ratio.
4- Temperature is holded still for the determinated period.
5- Furnace is cooled to the fixed temperature by the temperature/time ratio.
6- Furnace is cooled to the determinated temperature freely and the loop is finished.
All data below has to be observed and controlled for the system.
Temperature, vacuum pressure, water flow, trap temperature, return temperature, carbon differential pressure, vapor temperature, pump water pressure, heater current, pump current set values are adjusted, alarms are created and controlled.
Testing and maintenance are done by manual operation.
Heater, vacuum pump, water valve, pump and furnace valve are manually controlled.
Furnace temperature, heater current and furnace pressure is periodically logged in the data logging screen. The logs are kept for 90 days. The date selection is available to browse the logs. Reset button clears all the logs.
All fault logs related to the automation are shown on the alarm table. Past faults can be observed.