جستجوی مقالات مرتبط با کلیدواژه « environment » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

The water injection process is a common method for enhancing oil recovery from reservoirs. However, challenges arise, primarily due to the incompatibility of injected water with both oil and reservoir water. On the other hand, due to the limited availability of fresh water resources worldwide, the use of unconventional water sources is being considered. Among these sources, agricultural drainage water, particularly sugarcane irrigation water, is a significant source. In this study, the compatibility of two samples of sugarcane irrigation water with three samples of oil from southwest Iranian fields was investigated in terms of emulsion formation and organic matter deposition. Additionally, the compatibility of sugarcane irrigation water and a produced water sample was monitored in terms of mineral deposition through laboratory experiments. Furthermore, the results indicate that emulsion formation and phase separation occurred in the emulsion of sugarcane water sample 1 and oil A during the three-hour test period, with a 63% phase separation. However, a stable emulsion without phase separation was observed in the emulsion of sugarcane water sample 2. Similar experiments were conducted with oils B and C, and for both sugarcane irrigation water samples, the phase separation increased from 37% in the initial hours to 82% after three hours. Furthermore, the tendency for emulsion formation changes significantly with variations in the water-oil mixing ratio. On the other hand, no organic deposition resulting from the incompatibility of water and crude oil samples was observed. Overall, sugarcane irrigation water can be a suitable option for injection in some oil fields, but it is important to assess compatibility prior to field implementation. Moreover, no significant deposition was observed when both sugarcane water samples were mixed with the produced water, indicating the possibility of mixing water from different sources for injection. Furthermore, to evaluate the possibility of various depositions due to the injection of sugarcane water into the reservoir, simulation was performed using OLI scale chem software, and the probability of CaCO3, CaSO4, and Fe2CO3 deposition was determined.

Sustainability is the key to ensuring that our actions today do not limit the range of economic, social and environmental options for future generations. In fact, sustainable development is committed to preserving the environment and paying attention to the needs of future generations. The textile and clothing industry is one of the most polluting industries in the world, so special attention should be paid to its sustainability aspects throughout the textile and clothing supply chain. For this purpose, the assessment and improvement of social, environmental and economic effects at each stage of the entire supply chain should be considered. The textile and clothing industry sector is heavily involved in environmental, social, and economic issues, and sustainable design can lead to long-term use and reduce the wastage of materials and products. One of the most important findings of this research is the improvement of the awareness of designers and clothing manufacturers of sustainable development, which plays an important role in the application of the principles of sustainable development in the country. One of the solutions that can be offered in this regard is the optimal use of clothing in the best possible way. Buying clothes that are of high quality and longevity can be the best solution. Another solution is to recycle and make minor changes to the clothes that we do not want to use anymore. The most important solution to coexist with the environment is for people to turn to the business of sharing clothes.

According to the new findings of scientists, millions of tons of waste from plastic materials enter the oceans every year. Accumulation, decomposition, and penetration into organisms' life cycle and feed cycle pose a serious threat to the health of humans and the global ecosystem. The production of plastic materials worldwide has increased dramatically in recent years. Any plastic material that is consumed and then enters nature and seas as waste may be divided into many pieces and pollute the environment. Microplastics are directly transferred to the rivers and the sea through sewage or landfill leachate. Microplastics are bioavailable to organisms due to their small size. Their composition and relatively wide surface have made them suitable for absorbing organic pollutants. This article investigates the characteristics, sources of production, ways of entering and its effects on the environment, introduction and identification-analysis methods of these particles. Among the visual methods, the new method of qualitative and quantitative identification of microplastics using colorimetry with the help of fluorescent dyes has been noticed. 

Biogas is a sustainable energy source produced from organic waste. Raw biogas can be used to generate electricity, but since the energy content of biogas is directly related to methane concentration, it is necessary to improve the biogas and remove its carbon dioxide and other impurities to inject it into the gas grid. This article represents the biogas-improving process based on low-pressure steam compression, which is optimized with an expansion of the clean solvent exiting from the reboiler of the solvent recovery tower, and sending dense hot steam to the reboiler. Two common and optimal modes have been simulated by Aspan-Hasys software based on pure amine solvents. The obtained results showed an increase in the amount of carbon dioxide recovery, and a decrease in the heat load of the reboiler of the disposal tower to the amount of 3.62 GJ/tCO2, which is a 28.74% reduction compared to the base process.

The main purpose of this study is to identify the factors affecting the fashion and clothing industry with Environmental sustainability approach. The logic for using this approach in the present study is based on the assumption that today we are witnessing the development of the fashion and clothing industry, and this has led to the development of economic, environmental and social issues in this industry. The statistical population of the present study consists of 22 selected samples from active textile and clothing factories in the west of Mazandaran province and the census method was used for sampling. In order to collect data, the standard Step Ecotax questionnaire was used and its reliability was calculated to be 0.86. The findings of the present study indicate that all three dimensions of producers, consumers and the environment are effective on fashion and clothing design and also there is a significant difference between these three dimensions in terms of ranking, so that the dimension of producers in the first place, the dimension of environment in Second place and consumers were third.

With increasing population, reducing the amount of pollutants in the environment is especially important. Oil and gas refineries are one of industrial units which cause environmental pollution. Since all the hydrocarbon components recovered from the reservoirs are not separable, therefore inevitably a significant amount of these compounds, which are generally of high economic value, are burn in flares. In addition to the loss of many beneficial hydrocarbon compounds, flaring has many environmental damages. The main purpose of this paper is to provide the best way to separate and minimize flare gases and reduce the loss of gas hydrocarbons. For this purpose, the separation of gases sent to Parsian refinery flare was simulated using Aspen HYSYS software and operational enhancements were applied. Different types of amines for carbon dioxide separation were investigated and the best type was selected with the highest recovery rate. Moreover, sensitivity analysis were performed on important operational parameters and the results were analyzed. Finally the application of separated carbon dioxide for gas injection in gas reservoirs for pressure stabilization and the separated sweet gas for GTL process and conversion to more valuable compounds were suggested.

Increasing usage of fossil fuels, is polluting environment with an ascending rate. In addition to carbon dioxide, using crude oil leads to emitting sulfur oxides, which in the environment leads to acidification of rainfall and soil and pollution of water resources, and in human can exacerbate heart and respiratory diseases. Moreover, presence of sulfur in petroleum refining is unpleasant since can lead to catalysis deactivation, corrosion of equipment, scale formation, etc. To decrease effects of these pollutants, in many countries environmental regulations are developed to reduce sulfur in petroleum products. The process which is currently used in refineries to reduce sulfur level is hydrodesulfurization. This technology at high temperature and pressure by using hydrogen and in presence of the catalysts, convert sulfur atom in organic compounds to hydrogen sulfide. However, hydrodesulfurization faces with many obstacles and challenges, which in this paper most important issues in this regards are addressed.

Hypothis: Rubber powder with a very fine particle size, rough surface and very low impurities can be prepared by water jet technology. The use of this powder as a suitable additive in tyre compounds is very important from economic and environmental viewpoints.
Morphology of the water jet powder was investigated using SEM. The rubber powder was added to a SBR/BR-based tyre tread formulation and the curing behavior and mechanical properties of the resultant product were determined. A full factorial experimental design was also conducted to study simultaneously the effects of rubber powder, sulfur and carbon black levels on the curing and mechanical properties of tyre tread formulation. Furthermore, the modification effect of Vestenamer additive and curing agent on the formulation properties was investigated. When using design of experiments, for each property the regression models with linear and binary interaction terms on the basis of three variables were successfully developed and statistically validated.
Findings: The rubber powder showed a lowering effect on tensile properties, which was attributed to reduced crosslink density due to the sulfur migration from the rubber matrix to the powder phase. A small, but statistically significant negative effect on the aging, abrasion and resilience properties of rubber compound was also observed, However, the tear resistance and de Mattia crack growth were improved with increasing rubber powder content, that could be attributed to the lesser effect of rubber powder on the compound modulus. It was shown that with some increase in the curing agent, sulfur and accelerator dosage, it was possible to compensate for the tensile properties to some extent and for the abrasion, resilience and aging properties completely, whereas others remained relatively unchanged. It was also shown that except for abrasion, the Vestenamer processing aid had little improving effect in the presence of rubber powder.

Water pollutant is an issue that concerns all of the people. Considering the importance of the environment and water sources, in this study, simulation of refinery sour water purification unit has been investigated based on the determination of appropriate operating conditions. To predict the thermodynamic behavior of this system, Electrolyte NRTL activity coefficient model was used to simulate the sour water stripping tower. The simulation results showed that suitable feed temperature of column and tray spacing were 40 oC and 0.54 m, respectively. Also, the Concentrations of H2S and Ammonia reached to maximum amount at this conditions. Due to economic Considerations, feed volume flow rate of 38 m3/h was proposed.

Researchers predict that gas production will peak in the world between 2020 and 2050. Owning %18.2 of the world?s natural gas reserves, Iran is known as the largest natural gas holder in the world and the South Pars Gas Field, as the world?s largest gas field, owns about 40 percent of the country?s gas reserves. Iran is the third largest natural gas producer in the world by producing 192.5 trillion cubic meters of gas by 2015. These capacities can be applied to the implementation of general resistance policies, paragraphs 12, 13 and 14 in the oil and gas industry, and to the fulfillment of general environmental policies announced by the Supreme Leader and help the low carbon industry and the use of desired clean energies. This paper compares the amount of CO2 produced from natural gas with fossil fuels. Moreover, it deals with the role of 67% of carbon dioxide and 19% of methane from total environmental pollutants and 21-fold capacity of each methane molecule relative to carbon dioxide in global warming. And the role of natural gas in sustainable production, sustainable development, the implementation of general resistance policies and the emission of greenhouse gases from different fuels such as oil, coal, diesel, gasoline and natural gas has been reviewed and natural gas has been introduced as a clean, sustainable and environmentally friendly fuel due to its low CO2 emissions compared to other fuels.

Spent caustic wastewater is one of the most important environmental challenges due to high alkalinity, the presence of sulfur compounds and non-biodegradable pollutants. Therefore, in this research, the effective parameters of Electro-Fenton process including pH range (2-5), H2O2/COD (0.2- 0.745), temperature (20-60 °C), reaction time (45- 135 min) and current density (5-20 mA/cm2) have been investigated on the COD removal efficiency by adopting response surface methodology (RSM). The results indicated that H2O2/COD, temperature, pH, current density and reaction time have the most effect on the pollutants removal, respectively. The optimum conditions have been found at pH =4.8, current density =14.8 mA/cm2, temperature =57 °C, reaction time =63 minutes and H2O2/COD =0.63 with 96% COD removal efficiency. According to the results, by changing of initial COD within 12,500 to 60,000 mg/L range at the optimum conditions, the pollutant removal efficiency has been increased from 94% to 97%.

In this work, the effluent of Merox unit of Kermanshah Oil Refinery was used for un-hairing (tanning) regional sheep skin in leather production process. Four main factors influencing the hair removal process were studied in three levels including: the weight percentage of sodium sulfide (0.2-2%), calcium carbonate (4-6%), temperature (25-45°C) and time (30-90 min). Design of experiments (Design Expert software) was conducted with four mentioned variables and their effect on un-hairing efficiency (response factor) was investigated. The results showed the highest efficiency (99%) was achievable under optimum conditions of highest level of variables, while the 63% efficiency was obtained using tap water (instead of wastewater) under similar experimental conditions (level of variables). Moreover, the qualitative characteristic of un-haired hide was the same in two experiments. Adding calcium carbonate had no significant effect on un-hairing due to high alkalinity of wastewater. Using wastewater, considering 2% content of sodium hydroxide, increased efficiency and decrease the needs for calcium carbonate and sodium sulphide significantly. Using wastewater of Merox unit in skin-tanning leads to a decrease in unpleasant effluents of oil refineries and therefore the needs for chemicals and raw water in leather production industry, and as a consequence a reduce in environmental pollution generation.

Global warming caused by greenhouse gases is one of the main environmental threats that we face in the 21st century. With increasing concerns, research on converting CO2 in to valuable compounds has increased. In the past few decades, scientific consensus for capture, fixation and recycling technologies of CO2 increased. Today, methanol production, as one of the hydrocarbons that can be used in various industries instead of crude oil derivatives, is very important. Photo Catalytic conversion of CO2 into valuable compounds, in addition to reduce concerns about this pollutant, is a new way to produce synthetic compounds derived from carbon dioxide gas.
In this review paper, after presenting the different methods of application and conversion for CO2, photo catalytic conversion process will have been studied and then catalysts, the required reactions as well as the types of reactors will have been discussed.

Containers for packaging and storage of food represent one of the most popular uses of plastics and polymer additives. Due to low weight, high mechanical resistance, maintenance and easy transportation, the application of plastic bottles have increased. This paper investigates the effects of plastic bottles aspects of medical, environmental and energy consumption are discussed and compared with glass bottles. According to reported surveys, this is predicted that the growth of consumption plastics bottles will be 92000 ton in Iran in this year. Plastic bottles are not suitable for food storage because of their biodegradable property, recycling problem and their low quality after recycling. Releasing the hazardous substances in the air, especially during the manufacturing process, the emission of toxic compounds such as Antimony, Zinc, Bromide derivatives, and Phenol in water and food, are destructive effects on environment and human. Also, the usage of these containers is not cost effective because of their problems in recycling and the high cost to landfill the plastic bottle wastes. Versus, Glass bottles are made of minerals that can be recycled easily (15 -20 time) and have low cost recycling, so recycled glass bottles have a quality like the original bottles and less energy to primary energy production are needed. Therefore, glass bottles may be safe to store food.

Today, solar evaporators have been attracted researchers attentions due to their low cost, application facility and environmental considerations. They can be an appropriate alternative for thermal heaters, which use the fossil fuels. In this study, firstly a review on solar energy absorption systems has been presented and then manufacture and design procedure for a homemade solar evaporator, which can be used in buildings. This produced evaporator consumes 100 W electric current and 800 W.hr during a day and it can provide 48 liters distilled water in a day. Total cost has been calculated in three cases: 1-80% evaporation of input water with solar energy absorption efficiency of 100% or 50%, 2-100% evaporation of input water with solar energy absorption efficiency of 50%, 3-100% evaporation of input water with solar energy absorption efficiency of 50% with energy recovery in two cases of 50% and 75%.

In this research, Nanoemulsions of water droplets in gas oil have been prepared using combination of nonionic surfactants. Three formulations of the emulsion containing various amount of water as 5, 10 and 14 volume fractions (based on 100 volume fractions of gas oil) have been prepared, clear and stable, using a mixture of two surfactants containing sorbitan monooleate (20%) and sorbitan trioleate polyoxyethylene (20 mole ethoxylated) (80%) and adjusting the system HLB at 10. The effect of water content on droplets size, fuel calorific value, amount of gas emissions (environmental pollutants) and the exhaust gas temperature have been studied in a diesel engine, and it has been found that the amount of nitrogen oxide, soot, particulates, unburnt hydrocarbons and carbon monoxide are reduced. This study shows that the average droplet size of water formed (being 19.3-39 nanometers in this research) depends on the total concentration of surfactants and the amount of water used.

In this survey, the Paraxylen Plant located in Bandar Imam Petrochemical Complex was studied in the viewpoint of Environmental Management in four aspects: waste water, air pollutants, Noise pollution and solid wastes. This survey has been performed through 9 months of field and library work from April to December 2005. After recognition of process and resources of pollutants in studied plant, sampling points were choose and through 6 months quality parameters for waste water and air pollutants were defined. The results of this research show that the concentration of COD, OIL, TDS, parameters and phosphate in output waste water of studied plant were higher than national standards. Estimating the atmospheric pollutants (CO, NOX, SO2) in studied plant show that these parameters are less than the allowed range defined by Environmental protection organization. Study the Noise pollutants in related plant show that the highest balance of noise pressure is 94dB (A). In study of solid wastes in PX plant totally 11 types of solid waste, were identified and 7 of them were as Hazardous wastes