Life cycle assessment of clinker production using refuse‐derived fuel: A case study using refuse‐derived fuel from Tehran municipal solid waste

One of the techniques used to dispose of 4,000 tons per day (TPD) of non‐recyclable waste from Tehran is to burn it as an alternative fuel in cement kilns. This practice reduces emissions from landfills, prevents the loss of waste energy, and conserves fossil fuel resources. The aim of our study was to conduct a life cycle assessment (LCA) of clinker production in cement kilns using a combination of natural gas, mazut, a form of heavy, low‐quality fuel oil, and refuse‐derived fuel (RDF) from Tehran. We used SimaPro 7.1 software to perform an LCA of 1 kilogram (kg) of clinker produced using the following fuel combinations: the first scenario involved natural gas consumption alone, the second scenario involved a combination of natural gas and mazut, with the mazut providing 5% to 30% of the heating value needed to produce cement clinker in the kiln, and the third scenario involved a combination of natural gas and RDF (providing 5% to 30% of the heating needed in the kiln). The impact categories in the LCA of global warming, eutrophication, and acidification were assessed by the Center of Environmental Science of Leiden University (Centrum voor Milieukunde Leiden—CML) CML 2000 method. The results indicated that the third scenario, involving natural gas and RDF, reduced acidification by 2.14–11.5% and global warming by 0–1.3% relative to the first scenario involving the use of only natural gas. In addition, we observed a 0.65–3.81% reduction in acidification and a 0.9–3.8% reduction in global warming under the third scenario compared with the second scenario (co‐firing of natural gas and mazut). The amount of nitrogen oxides (NO_X) emitted from the combustion of the Tehran RDF was greater than that was emitted when burning mazut. Therefore, reduction of nitrogen from the RDF composition is necessary. This study indicates that the use of Tehran RDF (with reduced nitrogen) in Tehran cement kilns does not increase cement kiln NO_X, sulfur dioxide (SO₂), and carbon dioxide (CO₂) emissions; however, we need to conduct additional investigation into the chemical composition of the Tehran waste before using solid waste in place of fossil fuels.     

The Comparison of Lagrangian and Gaussian Models in Predicting of Air Pollution Emission Using Experimental Study,a Case Study: Ammonia Emission

Ammonia, as a colorless gas with a sharp odor, is considered as one of the created odors in the composting and landfill of solid waste. We used experimental data to study the robustness of AERMOD and the forward Lagrangian stochastic (FLS) in predicting ammonia emission in short range. The study area was Kahrizak landfill and composting plants, Tehran, Iran. The boundary layer parameters for the FLS were calculated on the basis of mean values of temperature, wind speed, and direction. While, the boundary layers of AERMOD were computed on the basis of exact meteorological data. The results depicted that AERMOD prediction at distances less than 1000 m from the sources and the locations inside the sources were poor. However, the results of FLS indicated more agreement with the field measurement, which the coefficient of determination was 0.83. Both models predicted, in the distance of 2000 m from the source, the ammonia concentration would be insignificant.     

Experimental study of benzene,toluene, ethylbenzene,and xylene (BTEX) contributions in the air pollution of Tehran,Iran

Urbanization and development are associated with air pollution, including emissions of volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, and xylene (BTEX). For this study, we measured and investigated the outdoor concentrations of BTEX in Tehran, Iran. National Institute for Occupational Safety and Health (NIOSH, 1996) methods were applied to measure the concentrations of BTEX in winter and spring of 2015 at 46 air monitoring stations. BETX concentrations were also measured at 19 monitoring stations in June and July of 2003. In 2003, BTEX compound pollutants were observed at greater concentration in the eastern, central, and southern zones of Tehran than in other zones. The average concentrations of the BTEX compounds were 238 parts per billion (ppb), 130 ppb, 69 ppb, and 118 ppb, respectively, for benzene, toluene, ethylbenzene, and xylene. The benzene to toluene (B/T) ratios ranged from 0.8 to 3.2, which indicated that the gasoline used in the city was of poor quality at that time. In 2015, the BTEX concentrations in District 19 (south of Tehran) were higher than in the eastern and central regions, which included restricted “traffic zones” and the extensive development of public transportation systems. In the restricted traffic zones, only public vehicles, such as buses, taxis, ambulances, etc., and other authorized vehicles are allowed to operate. By ameliorating the quality of gasoline, encouraging the use of late model private cars, and development of subway and public transportation during the years between 2003 and 2015, the BTEX concentrations have fallen to levels that comply with Iran's air quality standards. The 2015 measurements revealed that the average concentrations of the BTEX compounds were 5.3, 9.2, 1.5, and 2.6 ppb, respectively. The B/T ratio fluctuated from 0.39 to 0.76, demonstrating the remarkable role that vehicle traffic plays in BTEX pollution.     

Anthropometric hand dimensions in a population of Iranian male workers in 2012

Background. The mismatch between the hand size of workers and the size of industrial instruments is a growing concern; it can lead to various musculoskeletal complications. Currently, there are few reliable studies available to address this concern in Iran. This study was conducted to measure 30 upper-extremity parameters in a group of Iranian industrial workers. Methods. This study is a cross-sectional study on 529 workers. The study population was randomly selected from male Iranian industrial workers who were referred to the Yazd hospital occupational medicine clinic for surveillance evaluations. Results. The M (SD) age of the participants was 30.13 (8.29) years. Statistical analysis was performed using the mean, standard deviation and 5th, 50th and 90th percentiles for each measured hand dimension. A considerable number of dimensions were significantly different between the measurements of right and left hands in each examinee. The results showed significant differences between Iranian hand size and that of other populations. Conclusion. This study provided a valuable databank of hand dimensions in a population of Iranian male workers. These data can be used by manufacturers in designing high-quality hand-tools and industrial gloves, taking into consideration Iranian worker characteristics.     

Indoor air pollution evaluation with emphasize on HDI and biological assessment of HDA in the polyurethane factories

Today, many raw materials used in factories may have a dangerous effect on the physiological system of workers. One of them which is widely used in the polyurethane factories is diisocyanates. These compounds are widely used in surface coatings, polyurethane foams, adhesives, resins, elastomers, binders, and sealants. Exposure to diisocyanates causes irritation to the skin, mucous membranes, eyes, and respiratory tract. Hexamethylene diamine (HDA) is metabolite of hexamethylene diisocyanate (HDI). It is an excretory material by worker’s urine who is exposed to HDI. Around 100 air samples were collected from five defined factories by midget impinger which contained dimethyl sulfoxide absorbent as a solvent and tryptamine as reagent. Samples were analyzed by high-performance liquid chromatography with EC\UV detector using NIOSH 5522 method of sampling. Also, 50 urine samples collected from workers were also analyzed using William’s biological analysis method. The concentration of HDI into all air samples were more than 88 xxxμg/m³, and they have shown high concentration of pollutant in the workplaces in comparison with NIOSH standard, and all of the workers’ urine were contaminated by HDA. The correlation and regression test were used to obtain statistical model for HDI and HDA, which is useful for the prediction of diisocyanates pollution situation in the polyurethane factories.     

Designing of an environmental assessment algorithm for surface mining projects

This paper depicts the method used to quantify the environmental impact of mining activities in surface mine projects. The affected environment was broken down into thirteen components, such as Human health and immunity, Surface water, Air quality, etc. The effect of twenty impacting factors from the mining and milling activities was then calculated for each Environmental Component. Environmental assessments are often performed by using matrix methods in which one dimension of the matrix is the “Impacting Factor” and the other one is the “Environmental Components”. For the presented matrix method, each Impacting Factor was first given a magnitude between −10 and 10. These factors are used to set up a matrix named Impacting Factor Matrix, whose elements represent the Impacting Factor values. The effects of each Impacting Factor on each Environmental Component were then quantified by multiplying the Impacting Factor Matrix by Weighting Factor Matrix. The elements of the weighting factors matrix reflect the effects of each Impacting Factor on each Environmental Component. The outlined method was originally developed for a mining and milling operation in Iran, but it can successfully be used for mining ventures and more general industrial activities in other countries in accordance to their environmental regulations and laws.