Project Scope

Implementation of a Smart Plant Monitoring and Control System for a Coal Handling Plant: Featuring Condition Monitoring for Rotating Equipment

Scope:

• Detailed design and engineering
• Supply, installation, and commissioning of a redundant PLC-based control system
• Integration of SCADA
• Installation of field instruments (level sensors)
• Implementation of a condition monitoring system for rotating equipment

Background:

Our client, a leading coal mining company operating over 6 mines, aimed to modernize their coal handling plant at an opencast facility. The objective was to automate the handling of coal over a 0.5-kilometer conveyor system, enabling remote monitoring and control from a central location. This required the integration of a fault identification system from the coal’s arrival at the pit to its dispatch into railway wagons.

Plant Process:

1. Receiving and Transporting Coal:
   • Run-Off-Mine (ROM) coal is unloaded into four receiving hoppers via lorries.
   • Hoppers equipped with 200 TPH reciprocating feeders reclaim the coal and feed it onto conveyors.
   • Conveyors transport the crushed coal (-100 mm in size) to a tripper trolley conveyor.
   • The tripper trolley evenly distributes the coal into a ground bunker with a capacity of 1,000+ tonnes.
2. Bunker and Dispatch:
   • Plough feeders and slit-type openings in the bunker transfer coal to the reclaiming conveyor.
   • Coal is unloaded onto the dispatch conveyor, measured in a pre-weigh bin, and loaded into railway wagons.

System Description:

A real-time automated and centralized control system was implemented, enabling the start/stop of all equipment from a central control station. Key features include:

• Continuous Monitoring:
  • Reciprocating feeders
  • Conveyors
  • Plough feeders
  • Magnetic separators
  • Sump pumps
  • Exhaust fans
  • Tripper conveyors
  • Main transformers
  • Circuit breakers
• Condition Monitoring:
  • Monitoring 80 plummer blocks, conveyor drums, gearboxes, and motors for temperature, sound, smoke, and vibration levels.
• Emergency Control:
  • Equipment can be stopped from control stations using pull cord switches, belt sway switches, zero-speed switches, and chute overflow sensors.
  • Local control stations enable maintenance and testing.
• Visualization:
  • Visual display units provide continuous monitoring, showing equipment status, alarms, and detected faults.

Our Approach:

1. Remote IO Panels:
   • Placed at each of the four conveyor start-stations (substations) to capture trip-related information for prompt action.
2. Beltwatch System:
   • Deployed throughout the conveyor to identify pull cord engagements.
3. Central Control Unit:
   • Mitsubishi Electric control system+ SCADA visualizes equipment status, fire alerts from smoke detectors, tripper trolley location, and coal level status in the bunker through installed level switches.
4. Smart Sensors:
   • Banner Engineering’s smart vibration and temperature sensors monitor conveyor drums, motors, and gearboxes in real time, identifying mechanical fluctuations.
5. PLC System:
   • A redundant Mitsubishi IQR- series PLC system facilitates remote monitoring and sequential control.
   • Electro-mechanical equipment at the overground bunker and hopper loading complex is controlled via the PLC.
   • Automation of plough feeders ensures efficient coal disembarkation onto the reclaim conveyor.
   • Level sensors across conveyor chutes detect discharge jams.
   • Cameras provide real-time views of the conveyor system.

Results:

• Automation and Control:
  • Complete automation and remote monitoring of the Coal Handling Plant were achieved, reducing reliance on manual interventions.
  • Improved operational efficiency and effectiveness through centralized control.
• Reduced Manual Labor:
  • Lowered manpower requirements for operation due to automated control measures.
• Proactive Fault Management:
  • Real-time condition monitoring of conveyor drums, motors, and drives enabled proactive fault identification and timely remediation.

By implementing this smart monitoring and control system, the client achieved a highly efficient and automated coal handling process, enhancing overall plant performance and safety.