ارزیابی ضرایب انتشار COا، SO2 و NOx برای مشعل‌های گازی واحدهای فرآورش نفت و گاز

نوع مقاله: مقاله پژوهشی

نویسندگان

1 تبریز، دانشگاه صنعتی سهند، دانشکده مهندسی شیمی، مرکز تحقیقات مهندسی محیط زیست

2 خوزستان، مرکز علوم و تحقیقات دانشگاه آزاد اسلامی

3 اهواز، دانشگاه علوم پزشکی جندی شاپور

چکیده

محاسبه ضرایب انتشار یکی از روش‌های ساده و کم هزینه برای ارزیابی میزان آلایندگی حاصل از منابع آلاینده می‌باشد. در بین منابع آلاینده، ضرایب انتشار مشعل‌ها با خطای بالایی همراه است. چراکه میزان احتراق در مشعل‌ها به‌خصوص در حالت‌های اضطراری نامشخص بوده و اطلاعات دقیقی در مورد بازده احتراق واقعی مشعل‌ها در دسترس نیست. مقاله حاضر به منظور ارزیابی ضرایب انتشار سه آلاینده CO،اSO2 و NOx در مشعل‌ها انجام شده است. در این تحقیق، از روش محاسبه معکوس که بر اساس اندازه‌گیری محیطی همراه با مدل‌سازی استوار است، برای تخمین ضرایب انتشار آلاینده‌های گازی مورد نظر برای یک نمونه مشعل گازی در یکی از واحدهای موجود در مناطق نفت‌خیز جنوب ایران استفاده گردید. ضرایب انتشار متوسط آلاینده‌های CO، اSO2 و NOx برای این مشعل نمونه به ترتیب 07/1، 037/0 و lb /MMBtu/0168/0 با عدم قطعیت‌هایی معادل 5/27، 3/34 و 3/36% تعیین شد. مقایسه این ضرایب انتشار با ضرایب انتشار ارائه شده در مراجع، شامل ضرایب انتشار سازمان حفاظت محیط‌زیست آمریکا (EPA) و انجمن نفت آمریکای لاتین (ARPEL) نشان داد که هر دو مرجع برای تخمین میزان انتشار آلاینده‌ها به‌خصوص در مورد آلاینده‌های NOx و CO دارای خطای بالایی هستند. برای تعیین ضرایب واقعی مشعل‌های گازی، مطالعات دقیق در خصوص بررسی تأثیر شرایط محیطی بر بازده مشعل‌ها همراه با اندازه‌گیری آلاینده‌ها از طریق مشابه‌سازی مشعل‌های گازی، واقعی در آزمایشگاه مورد نیاز است.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of CO, SO2 and NOx Emission Factors for Gas Flares in Oil and Gas Processing Plants

نویسندگان [English]

  • D. kahforoushan 1
  • E. Fatehifar 1
  • A. Zoveydavi 2
  • N. Jafarzadeh 3
  • S.M. Hedayatzadeh 1
1 Environmental Engineering Research Center, Faculty of Chemical Engineering, Sahand University of Technology, Tabriz, Iran.
2 Khoozestan Azad university science and research center, Ahvaz, Iran.
3 Jondi Shapoor medical university, Ahvaz, Iran.
چکیده [English]

Emission factors technique is one of the simple and low cost methods for estimating pollution from air pollutant sources. However, emission factors of gas flare may have high uncertainty because in flares, especially under emergency conditions, flow rate of flaring gases as well as combustion efficiency are unknown. The aim of this paper is to evaluate SO2, NOx and CO emission factors in gas flares. For this purpose, emission factors were estimated using back calculation method based on modeling and pollutant emission measurement in ambient air in a selected flare in an Iranian oil and gas plant. SO2, NOx and CO average emission factors for selected flare are determined to be 0.037, 0.0168 and 1.07 MMBtu/lb, respectively, with uncertainty of 34.3, 36.3 and 27.5%, respectively. Comparison of calculated emission factors with United States Environmental Protection Agency (EPA) and Regional Association of Oil and Natural Gas Companies in Latin America and the Caribbean (ARPEL) emission factors showed that both emission factors have high uncertainty, especially for NOx and CO emission estimation. Therefore, it is necessary to study details of the influence of ambient conditions on combustion efficiency of flares as well as experimental simulation of actual flare to obtain more representative emission factors of flares.

کلیدواژه‌ها [English]

  • Emission Factor
  • Gas and Oil Processing Plant
  • Gas Flare
  • Air Pollution Modeling
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