Farshad Ahmadilar; Leila Khazini; Seyyed Shamedin Alizadeh
Abstract
Background and Purpose: Emitted pollutants in indoor environment of printing industries are the most serious risks to labor’s health according to WHO. The health effects of these pollutants range from acute diseases like eye irritation to chronic effects such as cancer and DNA damage.Materials ...
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Background and Purpose: Emitted pollutants in indoor environment of printing industries are the most serious risks to labor’s health according to WHO. The health effects of these pollutants range from acute diseases like eye irritation to chronic effects such as cancer and DNA damage.Materials and Methods: To study air pollution in indoor environment of the printing industry, using EPA methodology and ranked set sampling, samples were collected and then analysed through gas chromatography. Results: Based on the results, despite the concentration profile at the sampling sites, the total concentration of very volatile and volatile organic compounds at the nearest point to the dye tank, the location of the operator at a distance of one and two meters from the heliogravure machine, and the general working space were 20.83%, 5.41%, 1.85% and 1.46%, respectively . About 52% of the observed putants were ink organic solvents, 38% were sulfur compounds and 52% were nitrogen compounds. About 24% of pollutants have a complex structure of 12 carbons or more. The concentrations of pollutants observed not only exceed OSHA and NIOSH standards but also very high compared to similar international research; so that they are in the range of danger code announcement and have worrying health effects on employees. Conclusiuon: The results indicate the need for urgent intervention to reduce pollution in the printing industry. The preferred method for managing indoor air quality is control or replace the source of pollution, proper air conditioning equipment use, and simultaneous use of filters and air conditioning system to reduce emissions.
Amir Shojaei; Hossein Ghafourian; Linda Yadegarian; Kamran Lari; Mohammadtaghi Sadatipour
Abstract
Abstract Background and Aim :The release of volatile organic compounds from stationary and mobile sources increases the concentration of these compounds in the environment. These compounds are potentially hazardous to the environment and human health. The selection of management and engineering systems ...
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Abstract Background and Aim :The release of volatile organic compounds from stationary and mobile sources increases the concentration of these compounds in the environment. These compounds are potentially hazardous to the environment and human health. The selection of management and engineering systems has become essential for controlling the release of these pollutants. The aim of this study was to use an advanced catalytic ozonation process to reduce the concentration of these pollutants in industrial emissions. Materials and Methods:In this experimental study, the ozonation process in the presence of a catalyst bed containing ZnO nanocomposites coated on zeolite was used to treat the air contaminated with BTEX compounds as indicators of volatile organic compounds on a laboratory scale. In this study, the synthesis of nanocomposites was done using the chemical co-deposition method. SEM, XRD, BET, and FT-IR analyses were performed to investigate the structural properties of the nanocomposites. The initial concentrations of BTEX (50-200 ppm), the flow of the polluted air (5-20 l/h), humidity (0-75%), and ozone dose (0.25-1 g/h) were studied. The concentration of the BTEX compounds was measured by a Gas Chromatography (GC) device according to the NIOSH Guideline 1501. Results:The results of SEM, XRD, BET, and FT-IR indicated the proper synthesis of nanocomposites. Based on the laboratory results, the optimal process conditions were the initial concentration of pollutants equal to 50 ppm, the inlet flow rate of polluted air equal to 5 l/h, relative humidity of 25-35%, and the inlet concentration of ozone equal to 1 g/h. Under these conditions, the removal efficiencies of benzene, toluene, ethylbenzene, and xylene were 98, 96, 92, and 91%, respectively. Simple ozonation and adsorption processes had lower efficiencies than catalytic ozonation and the synergistic effect of the process was evident. Conclusion:Based on the obtained results, the process has the ability to reduce the concentration of BTEX compounds to the specified standards. This process can be used to treat polluted air in BTEX emitting industries that threaten human health and the environment. Article type:Research article Keywords: Volatile Organic Compounds; BTEX; Nanocomposite; Zinc Oxide; Ozone; Polluted Air