نشریه کاربرد شیمی در محیط زیست
پیاپی 39 (تابستان 1398)

Water is one of the most important chemicals and vital fluids without which living things are impossible. Today, many factors cause environmental water pollution that in this article, we try to absorb nitrophenol derivatives from contaminated water by poly co-hydrogel (vinylpyrrolidone-co-allylamine hydrochloride). Today, many factors cause pollution of environmental waters. In this article, we tried to absorb nanonitrophenol derivatives from contaminated water by co-hydrogel (vinyl pyrrolidone-co-allylamine hydrochloride). In this project, free radical polymerization at 70°C for 5 hours and 20 minutes using A.I.B.N as the initiator of N and N 'methylene base acrylamide as a crosslinking agent were prepared. then, the uptake of nitrophenol toxin from contaminated water by hydrogels was investigated. In this work, 5 to 20 ppm of nitrophenol and the amount of 0.02, 0.05, 0.1 g of hydrogel in different monomeric ratios (1:1, 1: 0.5, 1:2 The amount of adsorption was measured, which increased with increasing the amount of hydrogel and also increasing the concentration of nitrophenol.

In this study, in addition to a brief description of the production process of styrene and HIPS and study of their properties and structure, effective parameters in HIPS quality and the effect of various factors on the product, especially the impact of various rubbers in the Iranian market, both domestic and foreign, in appearance and index Impact susceptibility (IZOD) has been investigated. In the production process of HIPS, which must have clear and desirable standards, there are often situations that by changing the quality of raw materials and also changing the conditions of the production line and defective equipment of the production unit, product quality is not optimal and may be in the consumer market, Not sold and returned to the company. In addition, it is necessary that production conditions are always up to date and competitive. In this regard, by performing practical experiments on different samples of HIPS product, effective methods in optimizing product quality have been investigated and tried to make changes in process conditions such as temperature, pressure, mixer speed, type and amount of rubber, solvent content, The amount of additives, the use of more advanced catalysts, the best values and results to be obtained to use these results to produce cost-effective and high quality products.

In this study, in addition to a brief description of the production process of styrene and HIPS and study of their properties and structure, effective parameters in HIPS quality and the effect of various factors on the product, especially the impact of various rubbers in the Iranian market, both domestic and foreign, in appearance and index Impact susceptibility (IZOD) has been investigated. In the production process of HIPS, which must have clear and desirable standards, there are often situations that by changing the quality of raw materials and also changing the conditions of the production line and defective equipment of the production unit, product quality is not optimal and may be in the consumer market, not sold and returned to the company. In addition, it is necessary that production conditions are always up to date and competitive. In this regard, by performing practical experiments on different samples of HIPS product, effective methods in optimizing product quality have been investigated and tried to make changes in process conditions such as temperature, pressure, mixer speed, type and amount of rubber, solvent content, the amount of additives, the use of more advanced catalysts, the best values and results to be obtained to use these results to produce cost-effective and high quality products.

In this study, the effect of various factors on the permeability of CO2 and O2 gases on light polyethylene can be investigated. temperature, gas pressure and polymer thickness factors affect the permeability of gases. Various models such as DSC model and a device with ASTM standard and barometric method were used in the measurements. the results of the mentioned models show that with increasing temperature, the coefficients of permeability and permeability and solubility increase. also, increasing the pressure reduces the passing coefficient by a certain amount. But after a certain amount, the increase in pressure does not work. also, increasing the pressure has no effect on the permeability coefficient. In the case of solubility coefficient, increasing to a pressure range reduces this coefficient, then reaches a constant value.

Wastewater treatment, both in the industrial and urban dimensions, has many problems due to the use of expensive equipment and operational issues. Wastewater treatment of the pharmaceutical industry is a wide range of wastewater treatment methods that differ in structure and scope due to the variety of treatment methods, the variety of treatment plants, the variety of seasons, and even time. In this study, the analysis of serum company effluent after biological treatment during one year was investigated. Due to the high level of COD in some months of the year, the reduction of COD in the effluent of the serum manufacturing company after biological treatment and in the supplementary treatment stage was investigated using lime coagulant. The modeling and optimization of the COD removal process were studied using experimental design. The optimum COD removal efficiency was 18.9 minutes, pH was 5.6 and coagulant was 2 g / l, which was about 51%. In this study, the modeling for the process using the response procedure method and the optimization obtained for this method were in good agreement with the experimental data.

Considering safety measures in industrial and chemical facilities is a fundamental issue. Statistical figures and facts display the great impact of industrial accidents on humans’ life as well as economic and environmental damages. Industrial accidents are amounted to high percentages of accidents around the globe. In addition, some of these damages are irreversible. Therefore, discovering and preventing these damages and assessment of the risks which lead to these damages, requires specific strategies and guidelines in addition to risk analysis in industrial units. In this research paper, risk assessment and risk analysis of utility unit of Fifth Gas Refinery of South Pars Gas Complex has been studies. HAZOP Technique has been used for risk assessment of this Unit, which has been established to detect the procedural problems, so, the existing deviation has been assessed by HAZOP team. The result of the study showed the use of experts’ recommendations from HAZOP method for risk management and increasing safety and procedural measurements of the Unit. Based on compiled expertise, utility unit efficiency depends strongly on flow and compression for this unit, since the inflow stores in reservoirs initially and distributed in this unit with a proper pressure. Therefore, it is vital to regulate these parameters as far as possible and prevent their inadequate increase and decrease. The flow circulates in system with a normal procedural pressure rate and can prevent the probable damages such as lines break down due to high sensitivity against high tension and stopping pump and unit being out of service due to decrease of flow. the most important recommendations in this study include: installation of temperature and pressure alarms in unit. Therefore, based on the obtained results from this study, unit setup guidelines and policies have been reformed.