IDENTIFYING THE IMPROVEMENT POSSIBILITIES OF A FLUIDIZED BED BOILER WITH EXERGY ANALYSIS

Öz

In this study, a circulation-type fluidized bed boiler's exergy performance in a power generation plant was investigated. The boiler was examined not as a whole but by dividing it into its sub-systems. In the analysis, the sub-systems' exergy performance was evaluated in terms of criteria such as exergy efficiency, exergy destruction, fuel depletion ratio, relative exergy destruction ratio, exergetic improvement potential, and productivity lack ratio. In addition, the effect of different dead state temperatures on these exergy performance criteria is compared and discussed. As a result of the analysis, the highest exergy efficiency was achieved in the furnace with 80.2% at 6℃, while the highest exergy destruction occurred in the furnace as 18,118.9 kW at 27℃. The highest exergetic improvement potential was realized in Economizer-II with 11,593.82 kW at 6℃, and the lowest in Economizer-I at 27℃ with 631,9 kW. The effect of the increase in the dead state temperature on the exergy performance criteria applied to boiler sub-systems was variable. It showed its effect as an increase in some sub-systems and a decrease in others.

Anahtar Kelimeler

• Fluidized Bed
• Boiler
• Exergy Efficiency
• Exergy Destruction

EKSERJİ ANALİZİ İLE BİR AKIŞKAN YATAKLI KAZANIN İYİLEŞTİRME OLANAKLARININ TESPİT EDİLMESİ

Öz

Bu çalışmada, bir güç üretim tesisinde kullanılan dolaşım tipli akışkan yataklı kazanın ekserji performansı araştırılmıştır. Kazan bir bütün olarak değil, alt sistemlerine ayrılarak incelemeye tabi tutulmuştur. Analizde alt sistemlerin ekserji performansı, ekserji verimliliği, ekserji yıkımı, nispi ekserji yıkımı oranı, yakıt tüketme oranı, ekserjetik gelişim potansiyeli ve üretkenlik eksikliği oranı gibi kriterler bakımından değerlendirilmiştir. Ayrıca, farklı ölü hal sıcaklıklarının bu ekserji performans kriterleri üzerindeki etkisi kıyaslanmış ve tartışılmıştır. Yapılan analizler sonucunda en yüksek ekserji verimi %80,2 ile 6℃’de yanma odasında, en yüksek ekserji yıkımı ise yine yanma odasında 27℃’de 18.118,9 kW olarak gerçekleşmiştir. En yüksek ekserjetik gelişim potansiyeli 11.593,82 kW ile 6℃’de eko-II’de, en düşük ise 631,9 kW ile 27℃’de eko-I’de gerçekleşmiştir. Ölü hal sıcaklığındaki artışın kazan alt sistemlerine uygulanan ekserji performans kriterleri üzerindeki etkisi değişken olmuştur. Kimi alt sistemde artış kimi alt sistemde ise düşüş olarak etkisini göstermiştir.

Anahtar Kelimeler

• Akışkan Yatak
• Kazan
• Ekserji Verimi
• Ekserji Yıkımı

Kaynakça

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