3 posts
TimePosted 06/01/2009 13:34:22
asdasdfas says


Dear all

Please to answer me. How to decide air volume and coal require in burner for combustion process. I have below inputs which perhabs require. Again this input are subjected to what I have in my basket, kindly let me have your further information if require to panacea the solution.

Input available

At kiln    

Dia                    3.75m               
Heat req           1439KJ/KGCL



Know the answer to this question? Join the community and register for a free guest account to post a reply.

Michael Clark
321 posts
TimePosted 09/01/2009 09:41:56


You need the calorific value and ultimate analysis of the coal. Division of the heat required by the net calorific value of the coal tells you how many tonnes of coal you will need per tonne of clinker produced. From the ultimate analysis you can work out the oxygen required for combustion of the coal and from that the air required from the amount of oxygen in air.


32 posts
TimePosted 09/01/2009 12:08:54
guddu says


Dear sir
Thanks for your conscious coverage. . Enthalpy I can calculate, but concerning to stochiometric ratios, that pose me in my calculation. Apparently I don’t know what should be the ratio in case of cement. However I have below input parameter but how to use the stochiometric ratios to calculate air req that really needs your significant support.

Kiln spec
Dia 3.75
L 57
Fuel petcoke @ cal value 7500 kcal/kg
Heat req 1430kj/kgcl
Result This cal gives me the combustible fuel req ie 6500kg/hr. But on this basis what should be the air requirement, something I couldn’t calculate. I got to understand and been told by somebody to use socheiomestry ratio. Apparently I don’t know about this, but what you enlighten me to assess the coal properties will also require some significant support from your side. But to condensed and panacea the problem . I mentioned above the operating parameter , can you calculate the air requirement with Pressure required.

Again thanks for your generosity

In anticipation


14 posts
TimePosted 11/01/2009 16:54:27


Dear Rathul;

to calculate the stochiometric quantity I will post you the formular which I use for quick evaluation once you send me your email address.

However the stochiometric quantity gives you the theortical combustion air quantity required. For practical purposes you may have to to operate over-stochiometric (Landa appr. 1,1 - 1,2) for complete combustion or under stochiometric (Landa 0,8 - 0,9) for NOx reduction.

The actual combustion air requirement will therefor depend on type of calciner installed, excess Oxygen from kiln gas, mixing efficieny between kiln gas and tertiary air, calciner operating temperature and retention time in calciner to name just some of the mayor influences.

There is always a difference between the actual calulated results and the practical achievable/required quantities.

Best regards,