Application No.8: Fluid Batch Mixing Tank
This PL-Sim plant simulates a process carried out in an industrial shop floor whereby a
special compound is produced and stored to be subsequently used at some time
during a
production cycle. The animated setting features two tanks. In the first tank,
called Mixer, three different fluids are mixed and heated as part of a recipe. The
second tank, called Product, is used to store the compound.
The mixer is fed by three different pipelines, each supplying a different
ingredient. Valves
and pumps fitted to these pipelines, together with the level sensors and level indicators fitted to
the tank, allow accurate metering of the compound. The three ingredients are
red, green
and blue, respectively. The mixture colour is a function of the different percentages of
fluid, following colorimeter standards. For example, if the same amount of red and green
colour are mixed, the resulting mixture will be yellow.
By turning the heater on, after detecting the temperature sensor status and the value
shown on temperature indicator, the compound will be heated to a specified temperature.
A transfer pump-valve unit allows transfer of the finished product into the second tank,
where it will be stored. The pump-valve unit, at the outlet of the Product tank, is used
to feed industrial plants using the product. These plants are not shown and do not fall
within the scope of automation. The Product tank must always contain sufficient amount of fluid
to meet any fluid demand until a production cycle is completed.
The top section of the windows shows an operator panel complete with control push buttons
and status light indicators.
In another section, status indicators and ON-OFF sensor adjustments are shown.
Mix the three ingredients according to specified percentages. Heat the mixture for a
length of time, at a specified temperature, and then transfer the mixture into the Product
tank. We are confident that other procedures will be suggested by using your
imagination.
For initial applications, the use of all field signals is not absolutely
necessary. You may use
two ingredients only, and skip the heating step and so prevent the use of the warning alarm.
Additional functions, such as multiple recipes, may be gradually added.
