مطالعه‌ی فرآیند گرماکافت بستر ثابت روی چوب هرس درختان شهری در جوّ اکسایشی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری مکانیک بیوسیستم- دانشگاه ارومیه

2 دانشیار گروه مهندسی مکانیک بیوسیستم- دانشگاه ارومیه

چکیده

 
در این تحقیق اثر حضور اکسیژن بر فرآیند گرماکافت ضایعات چوب مورد بررسی قرار گرفت. نمونه­های مکعبی در ابعاد 5/2 سانتی­متر در دماهای 300 و 400 درجه سیلسیوس در جو اکسایشی گرماکافت شدند. دمای سطح و مرکز نمونه‌ها اندازه‌گیری و کسر اتلاف جرمی نمونه­ها محاسبه شد. نتایج نشان داد که افزایش دما باعث افزایش سرعت گرماکافت و افزایش نرخ تغییرات دما می­شود. همچنین دمای سطح نمونه­ها در گرماکافت اکسایشی به‌طور متوسط 100 درجه سیلسیوس بیشتر از گرماکافت در جو بی­اثر است که به معنی کاهش مصرف زمان و به تبع آن کاهش استفاده‌ی انرژی در فرآیند گرماکافت اکسایشی می­باشد. با توجه به ماهیت غیرخطی فرآیند گرماکافت ضایعات چوب، شبکه های عصبی مصنوعی با سه فاکتور زمان، اندازه­ی قطعات و دمای واکنش به عنوان متغیرهای ورودی به کار گرفته شد. نتایج حاصل از مدل­سازی توزیع دما و کسر اتلاف جرمی به ترتیب با ضریب همبستگی 9998/0 و 9991/0 تطابق خوبی با نتایج تجربی داشت.

کلیدواژه‌ها


عنوان مقاله [English]

The study of fixed bed pyrolysis process on urban pruned woods of trees in oxidative atmosphere

نویسندگان [English]

  • ahmad piri 1
  • Ali Mohammad Nikbakht 2
1
2
چکیده [English]

The purposes of this article are studying the effects of oxygen presence on waste wood pyrolysis process in order to produce bio-char. To reach the goal, cubic samples of size 2.5 cm pyrolized at 300 and 400 °C. The surface and center temperatures of samples were measured and their mass losses were calculated from the ratio of pyrolized mass to initial mass of the sample. increase in temperature caused increase in the rate of pyrolysis and temperature changes, but decrease the final efficiency of biochar. Moreover, the surface temperature of samples in oxidative pyrolysis compared with the pyrolysis in an environment containing inert gasses, is about 100 °C more, i.e. a reduction in time consumption and consequently in energy use during the oxidative pyrolysis process. According to the non-linear nature of waste wood pyrolysis process, artificial neural network (ANN) was used to model the temperature distribution and the mass loss of samples. The results of ANN were in a good agreement with the experimental consequences and showed the correlation coefficients of 0.9998 and 0.9991 in modeling of temperature distribution and mass loss of samples, respectively.

کلیدواژه‌ها [English]

  • waste wood
  • Oxidative pyrolysis
  • Temperature changes
  • Mass loss fraction
  • ANN
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