Characterization of particulate matter in the process of manufacturing titanium metal powder

Abstract

Working in the metal powder production environment may result in a high level of particulate matter, which might pose a health threat. The main objective of this study is to determine the amount and type of the particles that might be emitted at the main sections of the Titanium production process and evaluate and characterize the exposure risk and exposure variability within persons, between persons, and between groups to the community working in that environment and compare the results with the Occupational Health Limit. The samples were collected randomly using sampling pumps set at 2 l/min flow rate and 25 mm Polyvinyl chloride filters with a diameter of 0.8 microns. The weighing balance was to determine the amount of particulate matter loaded in the filter, X-ray powder diffraction to determine and quantify the crystalline particulate matter collected from the study area, X-ray fluorescence was used to determine the elemental composition of the particulate matter and Fourier-transform infrared spectroscopy was used to determine the arrangement of particulate matter through their movement. The assessment is computed from the location of the sample and variables. The results obtained by the weighing balance confirmed the low amount of the particulate matter loaded in the filters in all sample locations except at the TiCl(sub4) loading section. The same samples were analyzed by XRD and FTIR and the crystalline peak was identified confirming the presence of silicates and carbonate minerals. The analysis done by XRF confirms the presence of an oxide element. The association between variables and crystalline particulate matter concentration was assessed through linear regression modelling. This model was based on the calculation of mean, minimum and maximum and standard deviation values of each variable. The outcome variable respirable crystalline particulate matter concentration was log transformed before the analysis. All the variables showed a non significantly weak correlation with particulate matter concentration. The overall p-value for all variables showed statistically non significant association with log-transformed average particulate matter concentration (p = 0.853). As the distance increased by 1 m, the particulate matter concentration decreased by 0.05% with significant differences (Coefficient: -0.0005; 95% CI: -0.00091; P = 0.050). As the wind speed increased by every 1 m/s2, the mean of concentration particulate matter increased by 14% while every 1% increase in humidity showed a 0.2% decrease in average particulate matter concentration.