Spectronephelometric methods to determine microphysical characteristics of dust in aspiration air and off-gases in cement plants

Abstract

The information value of spectral directional scattering coefficients of cement dust released into both the atmosphere and aspiration air during cement production is analyzed in terms of the concentration and effective dust particle size based on a regression approach to solving the inverse problem. The most effective layouts of dust meters that combine ease of implementation with high accuracy over the entire range of physicochemical properties of dust are considered.Introduction. The activity of cement plants is unavoidably connected with extensive release of gas-dust streams into the atmosphere. The high concentration of solid pollutants (dust) in the releases inflicts enormous damage on the environment and causes irreversible loss of a large amount of raw material and finished product and premature deterioration of living quarters, etc. In addition to this, high dust concentrations in workplace air degrade the health conditions of the workers and reduce their productivity. In several instances they can cause occupational diseases. Therefore, an important problem for modern industry is protection of the environment from releases of dust and hazardous gases.Various dust-trapping apparatuses such as electric filters, sleeve filters, cyclones, inertial dust-traps, etc. are currently used to remove dust from workplace air of industrial facilities and gases released into the atmosphere [1-3]. However, in many instances the dust concentration of industrial releases exceed by several times the maximum allowed concentrations defined by regulations [2].According to current rules and standards, the mass concentration of dust in off-gases is used to monitor the effectiveness of existing dust-trapping apparatuses and to evaluate the throughput of designed ones [2]. This parameter is also applicable to health and epidemiological services for quantitative estimation of industrial atmospheric dust releases [4,5].Methods for measuring dust concentration are divided into two groups. Those of the first group are based on preliminary precipitation of dust particles and a study of the precipitate. Those of the second group do not include preliminary precipitation [3]. The principal advantage of the first group is the capability for direct measurement of the dust mass concentration. Its disadvantages are the labor-intensiveness of the measurements and the need for strict observance of lengthy procedures that required highly qualified personnel. As a result, air pollution becomes apparent only after the passage of a significant time period after its occurrence. Advantages of the second group are the capability for direct measurements in the gas-dust stream itself without the use of a sampling device, continuous measurements, high sensitivity, and the ability for total automation of the measurement process. The stream is not subjected to aerodynamic distortion during the measurements. Furthermore, these methods provide continuous information about the instantaneous dust concentration in the stream and trends in its change. This enab...

Impact of the cement dust emitted from the South Cement Factory in Tafila/Jordan on plant diversity of the surrounding area

“…Zvereva et al (2008) investigated the general pattern of changes in species richness and diversity of vascular plants due to environmental contamination, and associated habitat changes imposed by point polluters and identified the sources of variation in the response of plant communities to industrial pollution at a global scale. Lisenko et al (2012) suggested spectronephelometric methods to determine microphysical characteristics of dust in aspiration air and off-gases in cement plants. Edral and Demirtas.…”