زمینه و هدف: استفاده از سرزمین، بدون در نظر گرفتن تفاوت های اکولوژیک و پتانسیل های محیطی، باعث پیامدهای ناگوار و تخریب محیط زیست می شود که در نهایت، منابع طبیعی را در معرض تهدید قرار داده و محیط را از توسعه پایدار دور می کند. توسعه و گسترش پرشتاب، فقدان برنامه ریزی شهری و ترکیب بندی ناموزون شهرستان پارس آباد مغان نیاز به اعمال مدیریت صحیح در جهت جلوگیری از اثرات منفی ناشی از روند توسعه داشته و معرفی مناطق جدید جهت توسعه شهری ضروری می باشد. هدف این پژوهش، انتخاب جهات مناسب در محدوده شهرستان پارس آباد مغان برای توسعه شهری می باشد. روش بررسی: الگوی مدل مورد استفاده MADM و رویکرد آن تمرکز بر ارزش و روش جبرانی تحلیل سلسله مراتبی(AHP) جهت وزن دهی و تلفیق معیارها در محیط GIS بوده است. توسعه شهری، با استفاده از معیارهای مدل اکولوژی توسعه شهری، روستایی و صنعتی مخدوم و همچنین برخی از معیارهای اقتصادی، اجتماعی، هیدرولوژی و هیدروژئولوژی مانند فاصله از چاه، رودخانه، جاده، فرودگاه، مناطق صنعتی، گسل، شهرها و غیره نیز به این مدل اضافه شد. بحث و نتیجه‌گیری: نتایج حاکی از آن است از مجموع مساحت شهرستان پارس آباد، (2896/ 6238) هکتار به کاربری مناسب، (5083/18146) هکتار به کاربری متوسط و (067/110121) هکتار به کاربری نامناسب توسعه ی شهری اختصاص یافته است. اراضی مناسب و متوسط کاربری توسعه شهری بیشتر در بخش شمالی واقع شده اند که در حال حاضر نیز پراکنش فضایی مراکز جمعیتی پارس آباد در این نواحی است و از مهم ترین دلایل آن می توان به هم جواری با رودخانه ارس، شیب کم و نزدیکی به مناطق مسکونی اشاره کرد. پرونده مقاله

Caustic soda is a substance used for sweetening hydrocarbon products in oil refinery, gas and petrochemical units. The caustic soda-generated salts are increasingly formed during the process of removing impurities like mercaptans, sulfides and nitrates, which finally leave process system through spent caustic discharge. Spent caustic discharge into environment is prohibited due to the presence of compounds like organic and toxic substances, sulfide salts, mercaptans as well as high chemical oxygen demand (COD), emphasizing the need to treat such effluents. The present study aimed to apply catalytic wet air oxidation method for treatment of spent caustic effluent from Bandar Abbas oil refinery and to optimize related parameters. Experimental processes were performed in a 500-ml batch reactor. Catalyst concentration, residence time and stoichiometric air flow parameters were optimized by Box-Behnken design. Based on the results, optimal conditions for this process were the catalyst concentration of 123 ppm, the residence time of 3 h and the stoichiometric air flow of 4.1 l/h, with a maximum reduction of spent caustic COD of 42.2%. The results of optimization experiments were analyzed by Design Expert 11 software, the results of which documented that the three mentioned parameters had the greatest effect on reducing spent caustic COD. Prolonging residence time had no significant effect on COD removal. Polynomial equation based on the three mentioned variables was presented to predict the spent caustic COD changes. In this treatment method, in addition to a significant reduction in COD, the available toxic substances also reached less than 1 ppm. پرونده مقاله

Water is an essential component in the world. The presence of heavy metals in water has dramatic effects on health and ecological process in the environment. Heavy metal pollution in water bodies is an existing and developing problem in the world. There are several methods for removing these pollutions in water. A photocatalytic degradation is a useful approach to removal a variety of heavy metals from contaminated water. In this study, we summarized different types of methods for the removal of heavy metals especially arsenic and lead from water. Studies include different nano-photocatalyst and methods such as the use of TiO2 substrates, TiO2 nanotubes, and nanocrystals, organic and inorganic nanoparticles based on silica, a variety of nanomaterial-based polymers, magnetic nanoparticles such as zero-valent iron and zinc oxide, or using two or more of these nanomaterials at the same time as an adsorbent or oxidizer of pollutants, all under visible or ultraviolet light. Each method has some limitations and advantages and based on different research that scientists presented, the efficiency of each technique is depended on some conditions such as pH, adsorption time, solvent type, and UV light, so we still can’t introduce the best method. Nowadays researchers are trying to find a method with high efficiency, low cost, least risk for the environment, and without secondary contamination. Hopefully, researchers find many promising methods that can be used with high efficiency in the future by continuing the research. پرونده مقاله

Acidic mine drainage (AMD) contains large amounts of heavy metal ions and SO42, which can pose serious risks to human and environmental health. Anaerobic bioreactors are considered to be suitable methods for the treatment of acidic effluents due to some advantages such as the need for a small area, easy control, and simultaneous removal of sulfate and metals even in low concentrations. In this study, sulfate-reducing bacteria (SRB) performance was investigated in a semi-pilot scale down-flow fluidized-bed (DFFB) anaerobic reactor for SO42- and metals removal from the Sungun copper tailings AMD. The results indicated that utilizing SRB in the DFFB anaerobic bioreactor was an efficient, cost-effective, and environmentally friendly method for the treatment of effluents containing large amounts of SO42- and metals. All contaminants except Cr showed more than 70% removal after 24 h. The SO42- and Cu which had the highest initial concentrations showed removal efficiencies of 98.64% and 98.75%, respectively. Besides the removal of hazardous contaminants, the alkalinity of effluent increased remarkably. Also, the SRB had acceptable stability even after six consecutive cycles due to using AC granules as a support in the reactor which is an important parameter in industrial applications. پرونده مقاله