138 posts

### re Yet Another Raw Mix Design program

Avisgop,

As far as I can understand, there is no influence of the filter dust.

These dusts leave the kiln and come back to the kiln, summing up to nothing in the mass balance. (in stationary conditions)

Bypass dust is another story: they leave and don't come back, of course.

If you can assume that their composition is more or less constant, then it is an easy matter to take them into account in the toy calculation I have provided. This will be the case, for example, if you are only interrested in the main oxides.

By definition, the quantities are all positive numbers. Therefore, if you add a line or replace a line to represent the bypass dust, the quantity of bypass dust will be a positive number. Since bypass dust do remove something from the mass balance, you then
need to put **negative analysis for the bypass dust** (at least for those things that the bypass dusts do remove from the kiln, cost is an exception of course).

Note further that bypass dust usually have an analysis close to clinker. If this is confirmed, then there will be no effect of the bypass dust on the RMD, except for the total quantity of meal needed.

However, if you are considering big changes in chlorine inputs and other volatiles, and if you want to use this aspect in the calculations, then you cannot assume anymore that bypass dust would have a constant analysis. This is where you can see the limitations
of this toy RMD. Indeed, the bypass dust will extract a fraction of the total chlorine circulating in the kiln. This is easy to express mathematically, but this cannot be translated in this toy model.

This is the basic logic regarding dust, but there are variants.

For example, you might be interrested in performing all the calculations with bypass dust analysis based on the maximum quantity of chlorine they could remove from the given kiln. This is often useful, since the maximum capacity of chlorine input will be correctly
represented.

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20 posts

537 posts

### re RAW MIX CALCULATION

Attached are a couple of simple 3 and 4 component raw mix calculations in excel spreadsheets that I developed, plus a document explaining the derivation of the formulae for calculating a four component mix calculation using matrix determinants.

I hope they are useful to someone....

Regards,

Ted.