Published on MUST AS (http://www.must.as)

MUST Industries Brick Plant

Problems running the plant?

Please note that the MUST Industries Brick Plant ™ is implemented as a Java Applet that needs full access to your computer.

Your initial target is to produce bricks with the following properties:


In addition to this, you must add the correct amount of the colors red/green/blue to obtain the correct UV-VIS spectrum. An extensive process operators manual is given below the application. Read it, you really need the background information given there in order to succeed. Good luck!

You may also join the competition as the best MUST Industries Brick Plant ™ process engineer, by pressing the "Start test" button in the plant operator console. You will then be given a new set of target values, and it is your job to control the plant in order to produce bricks as close as possible to the quality target. When you feel you are close to the target, press the "Next target" button. In order to succeed with this, you better have a model of the plant first. Start by running the plant at various states (preferably using an experimental design) for collecting data. Then establish a model. Then start the test, using your model for finding optimal process set points. When you have completed the test, your results will be posted to our high-score list.

Java applet support is needed for MUST Simulator

Want to show off your optimization skills?

In cooperation with the Norwegian Chemometric Society, MUST AS is organizing a competition in process optimization. The winner is awarded the "Prosessoptimaliserings- prisen". For more information on the award, see this announcement. You can find the competition rules here.

Operators manual

The purpose of this manual is to give untrained personnel the information needed for operating the MUST Industries Brick Plant ™. After reading this manual, anyone should be able to operate the plant in such a way that only the world famous MUST Industries super-high brick quality is produced.

Process description

The unique MUST Industries Brick Plant ™ process containts these discrete manifacturing steps:

  1. The bricks are moulded from two different clay qualities, type A and type B.
  2. After moulding, the bricks are transported to the firing unit.
  3. When the brick leaves the firing unit, it is cooled down and spray painted.

Starting the plant

Plant startup is extremely simple, and chances are that the plant is already running while you read this. If not, you probably need a recent version of Java. Make sure you have the right tools for the job, the rest of the plant startup is completely automated!

The operator console

The MUST Industries Brick Plant ™ is a modern production facility, containing state-of-the-art instrumentation and control systems. This includes a modern and easy to use operator panel, and a process history database. The process database will store data for up to 100 bricks. When more than 100 bricks have been produced, data for the "oldest" brick will be deleted.

The operator console shows a visual presentation of the plant, and has got several sliders for controlling the process (the mainpulated variables). The functionality of the sliders are explained in the following chapters.

A visualisation of the quality control laboratory is also displayed in the operator console. In the MUST Industries Brick Plant ™ every brick is tested, and the current quality is displayed in the console (together with the target values).

The "Start test" button in the lower right area of the operator console will generate a new set of brick quality target values. Use this when you have managed to control the plant within the initial target values, and are ready for new challenges! By pressing this button you enter competition mode. Try reaching the targets, then hit the "Next target" button. After reaching your third set of targets, you may post your results.

The functionality of the "Plot" button, also located in the lower right area of the operator console, is explained in detail later.

Operating the moulding unit

In the moulding process unit two different clay qualities are mixed together, forming a brick. The ratio between the two clay qualities can be controlled from the operator panel, using the slider just below the mould. The amount of clay quality A can never go below 50%, but it can be increased up to 100% if needed for obtaining the correct quality.

Operating the firing unit

The temperature and residence time in the firing unit can be controlled, and these settings are extremely important for complete vitrification of the brick. The temperature and residence time is controlled using the sliders in the operator panel, below the firing unit.

Operating the color unit

After cooling down, the bricks are spray painted with enamel paint in the colors red, green and blue. The amount of each of the three colors can be controlled individually, making it possible to produce bricks in any color. The color control sliders are located below the spray paint unit, and are color coded (the red slider controls the amount of red, etc...). Be aware of the fact that if the brick temperature is too high, the applied enamel paint will degrade. When both temperature and residence time in the firing unit is high, this problem will occur. The result will be bricks of unacceptable quality.

Using the operator plotting console

If you want to see the process measurement trends, click the "Plot" button. This will bring up a new window, containing two plots and a table. Please note that data is only logged when you have opened the plot window.

The uppermost plot shows the historic values for the manipulated variables in the moulding and firing units (clay fraction, firing temperature and residence time) and the response values (brick porosity, permeability, crunchiness and hardness). If you have not made any set-point changes for the manipulated variables, the trends will simply be horizontal lines (and thus not easy to see in the plot...).

The lowermost plot shows the last acquired spectrum from the advanced UV-VIS online instrument located after the spray painting unit. It also contains the target spectrum for the ideal brick color.

The table on the left hand side of the plotting console displays raw data for process- and product quality measurements. It is only interesting to engineers and others who want to use the plant data in other software applications like Excel, The Unscrambler, Matlab, Analyze! etc. If you want to export data to another software application, simply right-click the table and select "Copy". Then go to your favourite modelling tool and select "Paste".

The process measurements (inputs) are tagged with the group name U, while the product quality measurements (outputs) are tagged with the group name Y. The brick color number is an indicator for how close the current brick color is to the target UV-VIS spectrum (100 is a perfect match). The desirability is an overall quality measure for the parameters porosity, permeability, crunchiness and hardness. When desirability is 1.0 you are producting bricks that match the target values for these parameters perfectly (but do not forget the color number).

Understanding quality

The MUST Industries Brick Plant ™ utilizes a highly non-linear brick production process. This section contains some hints on how to obtain the target quality with the least possible effort.

Focus on the three moulding and firing input variables first, and forget about the color. The colorization of the bricks will not affect the brick porosity, permeability, crunchiness and hardness anyway.

As the process is highly non-linear, it is not easy to find the relations between the three input variables and the four output variables without having a clear strategy on how to do this. Our suggestion is to run an experimental design, varying the input variables in a structured way and then study the effect on the output variables. Use the plotting screen when studying the relations between the inputs and outputs. Remember that a brick must pass all the production units and enter the laboratory before you see the effect of your process changes. The time lag may be quite substantial, try e.g. raising the termerature set point (SP) to the max and see how long it takes for the process value (PV) to get there!

For your convenience a "desirability" number, indicating how close you are to the quality targets, is calculated. You can see this number in the table part of the plot window. A desirability of 1.0 is a perfect product, but do not expect to get there every time... Sometimes close is good enough!

When you have reached the target for brick porosity, permeability, crunchiness and hardness, you can start fiddeling with the colorization of the bricks. Again, use the plot window and study the effect in the UV-VIS spectrum when adding/removing a color. You may also want to monitor the brick color number, try getting as close to 100 as possible. Also remember that the enamel paint used in this process may degrade if brick temperature is too high!

Health and safety consideration

The production of bricks involves heavy machinery and high temperatures, and there is plenty of noise and dust in the production facility. In short: this is a very dangerous working area!

Luckily, you are the control room operator, and you are located in a safe distance from the actual production area. You sit in a luxurious control room, drinking coffee and reading the newspaper, and do not need to worry about the highly toxic area where the bricks are made. But be aware: long hours in front of the operator console may cause permanent damages on your eyes and brain!

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