Particulate matter and elemental emissions from a cement kiln

Particulate matter emission from a stack attached to the kiln and raw mill in a cement plant was studied. Elemental (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and ionic (Ca2+, NO3−, SO42−) composition and particle size distribution of stack particulates, principal raw materials and products were determined. The feed rates of raw meal were found to be 144 and 18 t h− 1 at cyclone and bag house inlets, respectively, while stack emission of the same amounted to 86 kg h− 1, indicating bag filter removal efficiency of over 99%. Particle size distribution of stack particulates revealed that PM10, PM2.4 and PM1 had cumulative shares of 88%, 49% and 15%, respectively. Emission load of various elements from the stack ranged from 0.001 (copper) to 1.69 (iron) kg h− 1. Air quality modelling indicated that maximum ground level concentrations of As, Pb, Ni, Cd and Cr were much lower than the prescribed ambient air quality standards in India and also the Health Guidelines of USEPA and others. Particle size distribution and the elemental content of the raw materials, by-products and cement indicated that elemental exposure is likely from fugitive emissions during improper material handling and transport.

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► Particulate emission from kiln stack of a cement plant was 86 kg h− 1.
► PM10, PM2.5 and PM1 in stack emission were 88%, 49% and 15%, respectively.
► Small proportions of elements in the raw meal were emitted through the stack.
► Removal efficiency of bag filter for particulate matter was about 99%.
► Air quality model‐predicted values were below permissible limits and health guidelines.