The document discusses automation opportunities in sugar processing plants. It describes how automation can help optimize processes like cane feeding, milling, crushing rate control, boiler efficiency, evaporation, and continuous pan boiling. Automating control of key variables like drum boiler levels, mill extraction rates, and pan brix levels can help reduce losses, maintain quality, and improve overall plant efficiency while not necessarily reducing manpower. The document also provides several case studies of mills where automation has increased cane crushing capacity, reduced bagasse moisture and pol, and lowered energy use.
2. The Sugar Process
Continuous Flow Process
Highly Regulated Operating Conditions
Seasonal Operation
Limited Resources
Budgetary Limitations
Personnel Limitations
Remote Locations
New Challenges
Shrinking Margins due to Globalization
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3. Is Automation Needed?
Example 1
The Drum Level in a 2.4MPa 80TPH boiler can be
controlled manually. However, the risk of losing control is
high and the cost of instruments for this loop is too small
compared to the damage caused by the loss of control.
It is, therefore, better to automate this action.
Example 2
Starting and stopping of the Screened Juice Pumps in
the Mill House can be done manually. The cost of
isolating valves at the suction and delivery sides of the
pumps is too high to justify automating this action.
THE AUTOMATORS
4. Why Automate?
Reduce Losses
Capacity
Energy
Materials
Mechanical Failures
Maintain Quality
Unbiased Analyses
Independence from Manual Skill
NOT TO REDUCE MANPOWER
THE AUTOMATORS
5. Suggested Optimizations
Mill House
Cane Feeding (Capacity Enhancement)
Milling and Imbibition (Extraction Improvement)
Crushing Rate Optimization (Process Balance)
Boilers and Steam Management
Heating, Clarification and Evaporation
Raw Pans (Batch or Continuous)
Brix/Super-saturation Control in Batch Pans
Brix and Boiling Rate Control in Continuous Pans
Remelting and Refining
Powerhouse (Load-shedding)
THE AUTOMATORS
6. Control Systems
Discrete Controllers and Recorders
Low Cost in case of Few Loops
Poor Analysis Tools
Difficult to Maintain
PLC / Multi-Loop Controllers + SCADA
Availability and Maintainability Issues
Good for Machine Level or Area Wide Control
Distributed Control Systems
Easy to Implement and Maintain
Suitable for Plant Wide Control
THE AUTOMATORS
7. MILL HOUSE
Starting point of the Sugar Plant, providing:
Juice to the Process House
Bagasse to Boilers (at low moisture/ sugar traces)
Exhaust Steam to the Evaporators
Irregularities in the Mill House mean
Boiler and Steam Pressure Disturbance
Evaporation Process Mismanagement
Low or Poor Crushing for hours
High Maintenance Costs
Reduced Extraction
Reduced Energy Efficiency
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8. Mill House Automation ResultsYear Plant Setting Achievement
1997/
98
Shahtaj Shredder with 2 Cutters, 5 Mills Capacity enhanced to 11,000 from 8,500
Pol down to 1.8
2003 JDW-1A Shredder with 3 Cutters, 6 Mills Capacity enhanced to 8,500 from 6,500
2004/
05
JDW-1B Shredder with 3 Cutters and
Motorized Pressure Feeders on Mill
1/Mill 6
Never operated Manually.
Capacity 14,000 TCD
2006 JDW-2 Fibriser, 5 Mills Capacity enhanced to 10,000 from 7,000
2007 Al-Abbas Fibriser, 5 Mills, 1 on Motor Capacity enhanced to 7,500 from 5,500
Pol down to 1.6
2008 JDW-3 Shredder with 2 Cutters, 6 Mills Never operated Manually.
Capacity 15,000 TCD
2011 Noon Shredder with 2 Cutters, 4 Mills Capacity enhanced to 9,000 from 7,000
2013 Khairpur Shredder with 2 Cutters, 4 Mills Capacity enhanced to 7,000 from 5,000
2015 Chaudhry Shredder with 2 Cutters, 5 Mills Capacity enhanced to 10,000 from 9,000
Pol down to 1.6
2015 Sheikhoo Unigrators with 2 Cutters, 7 Mills, 3
on Motor
Capacity enhanced to 16,000 from 13,500
Pol down to 1.8
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10. CANE FEEDING: Advantage
Enhancement of Crushing Rate—up to 15%
Regulation of Bagasse Supply to Boilers
Improvement in Mill 1 Extraction
Reduction in Damage to Mechanical
Assemblies of Mill 1, Cane Carries, Shredder
and Cutters
Regular and lowered Energy Consumption at
the above devices
THE AUTOMATORS
12. MILLING: Advantage
Improved Extraction at all Mills
Reduced Bagasse Moisture and Pol
Maintained Overall Extraction Results at
Variable Crushing Rates
Reduction in Damage to Mechanical Assemblies
of Mills, Inter-carriers, and Pumps
Sustained Steam Consumption at Different
Crushing Rates
THE AUTOMATORS
13. Crushing Rate Optimization
Under Crushing
Loss of Production
Energy Losses
Over Crushing
Saturation in Boiling House
Increased Steam Demand
Boiler Inefficiencies
Millhouse Stoppages
Loss of Production
Energy Losses
Equipment Damages
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15. Other Optimizations in Sugar Plant
Boilers
Efficiency Enhancement
Pressure Stability
Evaporators
Steam Economy
Syrup Brix Improvement
Continuous Pan
Uninterrupted Brix control for B & C Sugar Boiling
Correlated Molasses and Massecuite flows for regular Vapor consumption
Minimal Water Addition
Sugar Refinery
Remelter Stabilization
Maintained pH Control
Deep Bed Filters
Batch Pan
Reduced Strike Time
Manual Washing
THE AUTOMATORS