نوع مقاله : مقاله مروری
نویسندگان
1 دانش آموخته کارشناسی ارشد، گروه محیط‌زیست، واحد اهواز، دانشگاه آزاد اسلامی، اهواز، ایران
2 استادیار گروه محیط‌زیست، واحد اهواز، دانشگاه آزاد اسلامی، اهواز، ایران
چکیده
فلزات سنگین از منابع مختلف تولید شده و اکثر آلودگی‌های ناشی از آن‌ها به منابع آبی وارد می‌شوند. بیشتر آن‌ها به علت سمیت و سرطان‌زایی برای انسان و محیط‌زیست خطرناک هستند. برخی از آن‌ها مانند کادمیوم، سرب و کروم در غلظت‌های کم نیز دارای اثرات سمی هستند. حذف فلزات سنگین از فاضلاب در سال‌های اخیر با توجه به قوانین محیطزیستی مورد توجه قرارگرفته است. فاضلاب صنعتی حاوی فلز سنگین باید قبل از تخلیه در جریان آب، تصفیه شوند اما فرآیند تصفیه پرهزینه است. پژوهش و توسعه روشهای کارآمد با کمترین هزینه و بیشترین کارایی در حذف آلاینده‌های محیطزیستی مخرب مانند فلزات سنگین یکی از تلاش‌های کنونی جامعه بشری است. جاذب‌هایی که مقرون به‌صرفه بوده و قابلیت استفاده مجدد داشته باشند، قابل کاربرد در صنایع هستند. روش های مرسوم معایبی دارند و بههمین دلیل علاقه‌مندی فراوانی به شناخت و استفاده از مواد بیولوژیکی در دسترس و سازگار با محیط‌زیست و تجاری‌سازی آن‌ها وجود دارد. این مطالعه به شیوه کتابخانهای با استناد به منابع و جستجو در مقالات متعدد انجام شد. نتایج این مطالعه نشان داد انجام تصفیه بیولوژیکی بهوسیله قارچ، مخمر، باکتری و جلبک نسبت به روشهای رایج دارای مزایایی مانند کاهش هزینه، کاهش حجم دفعی، مصرف انرژی کمتر، راندمان بالاتر، قابلیت احیاء جرم بیولوژیکی و آلودگی کمتر محیطزیستی میباشد. مقایسه صورت گرفته بین گونه‌های جلبک سبز، قهوه‌ای و قرمز جهت حذف کادمیوم و سرب نشان داد ظرفیت جذب جلبک قهوه‌ای با حداکثر ظرفیت جذب mmol/g 1/239 بیشتر از سایر گونه‌های جلبک بود.
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
Investigation and Comparison of Biosorbents for the Removal of the Heavy Metals )Cadmium, Chromium and Lead( from Industrial Wastewater
نویسندگان [English]
- Hamide Rashidi 1
- Forouzan Farrokhian 2
- Somayeh Zallaghi 1
- Meraj Amirjani 1
1 M.Sc. Alumni, Department of Environment, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran
2 Assist. Professor, Department of Environment, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran
چکیده [English]
Heavy metals are derived from various sources and majority of their associated pollutants enters water resources. Most of them are dangerous to humans and the environment due to their toxicity and carcinogenicity. Some of them, such as cadmium, lead, and chromium in low concentrations, also have toxic effects. The removal of heavy metals from wastewater has been considered in recent years due to environmentally protection regulations. Industrial wastewater containing heavy metals must be treated before being discharged into the water stream, but the treatment process is costly. Research and development of new and efficient methods with the lowest cost and highest efficiency in the removal of harmful environmental pollutants such as heavy metals are one of the current efforts of human society. Cost-effective and reusable adsorbents can be used in industry. Conventional methods have their own disadvantages; hence, there is a great interest in recognizing and using available and environmentally friendly biological materials and their commercialization. This study was literature review based in which several papers were reviewd from different databases available. The results of this study showed that biological treatment by fungi, yeast, bacteria, and algae has advantages over conventional methods such as cost reduction, reduced waste sludge, lower energy consumption, higher efficiency, biomass reduction capacity and less environmental pollution. Comparison between green, brown and red algae species for cadmium and lead removal showed that brown algae adsorption capacity with a maximum adsorption capacity of 239.1 mmol/g was higher than other algae species.
کلیدواژه‌ها [English]
- Adsorption Capacity
- Biosorbents
- Chemical Removal
- Physical Removal
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