Transcript PRO-PLAN Pulp Mill & Recovery Scheduling System

PRO-PLAN
Pulp Mill & Recovery
Scheduling System
PRO-PLAN - Pulp Production
The Pro-Plan Pulp Mill & Recovery Scheduling System is a
short to medium term scheduling and simulation system to
determine the maximum Pulp Mill production rate consistent
with constraints on:
pulp demand and storages,
•weak black liquor storage and evaporator throughput, and
•white liquor supply.
Applicability
• It is especially useful when two or more
pulp lines are vying for a limited supply of
white liquor, or limited black liquor
processing capacity.
• Rules are employed to determine priorities
and allocate available capacity logically.
Recovery Throughput
GL
Evaporators
Recovery
Boilers
Clarifier
It will also calculate the appropriate production rates for
evaporators, recovery boilers, recausticizers and lime kilns to
achieve and maintain the optimal levels in WBL, SBL, Green
Liquor and White Liquor storages.
Mill Coordination
Causticizers
GL Clarifier
WL Clarifier
Lime Kiln
It is intended as an aid to mill coordinators, and Pulp Mill,
Recovery and Recaust. operators to determine the most
appropriate production rates for maximising production and
minimising rate changes.
Optimal Production Rates
With no constraints, the model will calculate production rates to
achieve and maintain the levels in the pulp silos and liquor
storages that will best cope with unplanned shuts upstream or
downstream of each storage.
This is based on the probability of plant downtime upstream and
downstream of each storage.
Results
Maximise Available Capacity
Demands
Minimise Rate Changes
Constraints
Increased Production
Uniform Quality
Pro-Plan
Demands
Constraints
Better Storage Management
Reduced Inventory
Less Shuts
Lower Costs
Constraints
If there is a mismatch in pulp demand and minimum or
maximum production, best use will be made of the available
capacity in the storages to maintain production.
Constraints include white liquor supply, black liquor processing,
or plant throughput. The plant bottleneck may change from day
to day.
If pulp mill production is limited by white liquor supply or
evaporator throughput, the maximum production rate is
calculated according to the current priorities and available
capacity in the white liquor or WBL systems.
The system also determines whether:
Other Functions
• washer Dilution Factors need to be changed to reduce
WBL volumes,
• evaporator performance has degraded and the WBL
system has capacity for an evaporator wash.
• recycling of strong black liquor back to the weak black
liquor system is required.
PRO-PLAN I/O
The Inputs are:
• Paper machine making
plans
• Planned Shuts
• Current stocks
• Restrictions
• Plant reliabilities
The Outputs are:
• Optimal levels
• Optimal production
rates
• Predicted levels
• Predicted stocks
The Business Case
• How often does the digester need to shut or
slowdown due to a breakdown or restriction
in another area?
• How is the new rate determined?
• What is the lost opportunity?
• How are tank level and stock level targets
set now?
Financial Benefits
The financial benefits from using the PRO-PLAN Pulp Mill Scheduling System will vary
from mill to mill, and are dependent on the types of constraints and the method of operation
of the mill prior to using the system.
Typical improvements might be:
Better utilisation of capacity
Increased production of 1% of 500 tonnes/day for 350 days @ $200 margin = $ 350,000 p.a.
Better storage management
If there are 10 unscheduled upsets per year, and the storages are 5% closer to optimal levels:
10 x 5% x 500t x $200 = $ 50,000 p.a.
G2
Pro-Plan has been developed using Gensym’s G2 platform.
G2 is a graphical, object-oriented “expert system” for
building intelligent operations management applications.
These applications reason about operational data in real
time to provide advice and take corrective actions. G2
enables organisations to dramatically improve operational
availability, safety and optimisation.
Contact Procex
To discover more about Pro-Plan and its potential payback
for your situation, contact Norm Lasslett at Procex on:
Tel/fax: (613) 9386 1235
Mobile: 0418 378 453
Email: [email protected]
PRO C EX
Procex Pty Ltd ACN 076 092 370
39 Balmoral Avenue
Brunswick East, Australia 3057
Procex Pty Ltd
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