Stockpile Planning
Client: Dampier Salt
 |
Building a salt stockpile at Lake MacLeod |
A Powerful Tool for the Salt Industry.
In a highly competitive international market for salt, Dampier Salt
[Operations] (DSO) has a reputation for being one of the most reliable
suppliers of consistent high quality bulk solar salt. As part of its
plan to increase productivity, DSO wanted to evaluate the long term
effects of different stockpile sizes on its ability to reliably meet
the demand from clients. Moreover, each of the massive 120-tonne
trucks which haul salt at Dampier Salt's Lake MacLeod operation in
Western Australia costs about $400,000 a year to run. The trucks cost
$100,000 a year even when they are not used.
Now, thanks largely to a simulation model developed by the CSIRO,
Dampier Salt has been able to cut one truck from its 12-vehicle fleet,
while still improving the efficiency of operations at Lake MacLeod.
With the help of the CSIRO package, the company is considering whether
it could cut the truck fleet down to ten.
A model of the salt production operations was developed for use as
a planning tool to help evaluate likely outcomes of different
operating policies. It incorporates most aspects of the salt
production process at Lake MacLeod, including salt growth due to
evaporation in the crystallisers, stockpile levels at different stages
in the production process and the shipping demand, particularly the
arrival patterns and tonnages of ships at the port. The model also
includes operational factors such as harvesting, washing and drying
the salt, transporting the salt between stockpiles and loading the
ships. The operational processes in the model were subject to weather
patterns and equipment availability and maintenance schedules.
The model was interfaced to Lotus 123. This allowed the staff at
DSO to use a familiar spreadsheet package to enter data for different
operating scenarios, to run different simulations and to analyse and
graph the output from the simulations.
In order for Dampier Salt to maintain its high quality
and reliability of supply, involves maintaining large stockpiles of
expensive processed salt, keeping a careful track of shipping
schedules and weather conditions, and maintaining the capacity to
shift salt at short notice from stockpile to dockside. To keep this
front end of operations working efficiently, salt has to be
continuously moved from crystallisers to washing facility, then to a
'wet' stockpile and - after drying for two months - on to a 'dry'
stockpile near the docks. As clean dry salt has to ready at any time
to move up to replenish the dockside stockpiles, this means that
scheduling decisions have to be made months in advance.
The CSIRO operational stockpile planning software now enables
simulation runs to be set up for five to 20 years ahead. This allows
DSO to investigate the medium and long term effects of different
production policies by examining 'what if' scenarios far into the
future as well as investigating how the company can achieve
efficiencies with different stockpile and truck fleet options.
Over a period of time the model has been modified to reflect the
working needs of the management and staff at the Lake MacLeod
production facility.
As a result of this work, DSO has been able to substantially reduce
its operating costs while maintaining its reputation as a reliable
supplier of high quality salt.
Meanwhile the CSIRO team is applying the same modelling techniques
to the company's similar but larger salt facility at Dampier in
Western Australia. A further stage of this project would involve
integrating operations at both sites.
CSIRO is also looking beyond the salt industry to other possible
applications of its planning software.
Client Feedback
CSIRO's work has definitely helped us understand our own operational process more clearly. It is an excellent tool for examining 'what if' scenarios far into the future and it demonstrates how we can achieve efficiencies with different stockpile and truck fleet options.
Ron van Zelzen, Acting General Manager, Dampier Salt, June 1993
Further Information
For further information, please contact
Andreas Ernst
|
To top