1156 posts
Re: Burning
This is a big question! The merit is that the output of the kiln can be boosted by up to 15 per cent, the demerit is that the oxygen is expensive and therefore the costs of producing the additional clinker are higher. If market demand exists with good prices for cement then oxygen enrichment can be a good option. There are a number of kilns in the USA using oxygen enrichment of either the main burner or the precalciner. It is worth noting that CEMEX USA consider oxygen enrichment of precalciner firing to be their technology for which they have lodged a patent. You can find papers on oxygen enrichment in the proceedings of the IEEE conference in Vancouver 2001.
Know the answer to this question? Join the community and register for a free guest account to post a reply.
1156 posts
Burning Question 10
Does better nodulisation mean more consistent size of nodules with less dust or with less large nodules ? What might be wrong if always getting a large portion of large nodules (4-6 inches in diameter), even at 25 per cent liquid phase, which isn't high, and ALm of kiln feed ranging from 1.55-1.75. Kiln is typically run at 3.5rpm. The large nodules are only visible on kiln stops when there is a chance to look into the cooler, before the clinker goes through the crusher.
1156 posts
Re: Burning
Your chemistry does not sound abnormal and we have discussed the possibility that the large nodules are caused by MgO variation before. A further remote possibility would be Mn2O3 variation where slight increases cause the formation of vary large balls and also take the coating out of the burning zone. However, that is a long shot.
1156 posts
Burning Question 1
Our clinker chemical composition is as follows: SiO2= 21 per cent; CaO= 64 per cent; Al2O3 = 6.0 per cent; Fe2O3= 5.2 ; K2O = 0.4 per cent; SO3 = 0.55 per cent; MgO =1.0 per cent; Free CaO = 1.0 per cent and the liquid = 34.5 per cent. Liter Wt 1380g/ l. If there is slight reduction in the liquid the clinker becomes dusty though the free CaO is under control. Here it seems the Al2O3 comes from limestone does not get into liquid though the calculated liquid is high.If slight reduction in Fe2O3 content results in dusty clinker. We add aluminous laterite and hematite ore as fluxes. The question is how to differentiate between the actual liquid and calculated liquid.Does the optical microscopy help in this regard? From your experience give a clear picture on how to reduce the liquid content with improved nodulisation and to have better refractory life in the burning zone. Even the Spinel bricks give only( refra mag-85 of refratecnik) six month's life.