NUMERICAL ANALYSIS OF 330 MWth ÇAN POWER PLANT CIRCULATING FLUIDIZED BED BOILER BY COMPUTATIONAL PARTICLE FLUID DYNAMIC METHOD

Abstract

CFBB (Circulating Fluidized Bed Boiler) systems that is foregoing as efficiency and enviromental combustion of the low quality lignites that have %88 in the Turkish lignites. In the present study, Çan TS numerical analysis were conducted by CPFD(Computational Particle Fluid Dynamics) method with it was reached that boundary conditions and geometrical knowledges of the Çan TS CFBB system by otomation and control room. Pressure, temperature, O₂, CO₂, H₂O and SO₂ mole fraction changing in the combustion chamber were investigated in the numerical analysis. In the study results, pressure, temperature, O₂, CO₂, H₂O and SO₂ mole fraction of the bottom of the furnace is relatively 108401 Pa, 1093 K, 0,01, 0,04, 0,077, 0,005 and pressure, temperature, O₂, CO₂, H₂O and SO₂ mole fraction of the exit of the furnace is relatively 103347 Pa, 1015 K, 0,081, 0,05, 0,049, 0,003. It is showed that very good compliance with numerical and practical results.Also, important emissions and particule hydrodynamic flow are modelled with combustion and pressure properties by improved mathematical model. It is showed that, mathematical model that is improved by CPFD method will have great benefits in modeling studies. As a result of the study,it is showed that optimizable of the small and large capacity(0,5-100 MW_th) of the CFBB systems with CPFD method using validated numerical model.

Keywords

• Circulating fluidized bed boiler,Computational Particle Fluid dynamics,Combustion,Particle hydrodynamic flow,Numerical analysis

330 MWth ÇAN DOLAŞIMLI AKIŞKAN YATAKLI TERMİK SANTRAL KAZANININ HESAPLAMALI PARTİKÜL AKIŞKANLAR DİNAMİĞİ METODUYLA SAYISAL ANALİZİ

Abstract

Son yıllarda Türkiye linyitlerinin %88’ini oluşturan düşük kaliteli linyitlerin temiz ve verimli bir şekilde yakılabilmesini sağlayan en önemli yakma teknolojisi olarak CFBB (Dolaşımlı Akışkan Yataklı Kazan) sistemleri öne çıkmaktadır. Bu çalışmada, çalışır durumda ve 330 MW_th kapasitesindeki ÇTS (Çan Termik Santrali) CFBB sistemine ait otomasyon odasından alınan sınır koşulları ve yanma odası geometrik parametreleri dikkate alınarak, CPFD (Hesaplamalı Partikül Akışkanlar Dinamiği) metodu yardımıyla sistemin sayısal analizi gerçekleştirilmiştir. Analizlerde, yanma odasındaki basınç, sıcaklık, O₂, CO₂, H₂O ve SO₂ mol oranlarındaki değişimler incelenmiştir. Elde edilen analiz sonuçlara göre,  ÇTS kazan tabanındaki basıncın 108401 Pa,   sıcaklığın 1093 K, mol oranları ise O₂ için  0,01,  CO₂ için 0,04, H₂Oiçin 0,077  ve SO₂ için 0,005 olduğu gözlemlenirken, kazan çıkışındaki ise sıcaklığın 1015 K, mol oranlarının O₂ için  0,08,  CO₂ için 0,05, H₂O için 0,049 ve  SO₂ için 0,003 olduğu görülmüştür. Sunulan çalışmada kapsamında,, pratik sonuçlarla oldukça uyumlu olduğu sayısal sonuçlar elde edilmiştir. Gerçekleştirilen matematiksel modellemede, yanma ve basınç özelliklerinin yanı sıra önemli emisyonlar ve partikül hidrodinamik akışı da modellenmiştir. Bu durum da CPFD metoduyla geliştirilen matematiksel modelin,akışın ve yanma prosesinin modellenmesinde çok büyük kolaylık oluşturduğunu göstermiştir. CPFD metoduyla doğrulanan sayısal model kullanılarak, 0,5-100 MW_th arasında değişen farklı kapasitede CFBB sistemlerinin tasarımları ve sınır koşullarının  optimize edilebileceği sonucuna ulaşılmıştır.

Keywords

• Dolaşımlı akışkan yataklı kazan,Hesaplamalı partikül akışkanlar dinamiği,Yanma,Partikül hidrodinamik akışı,Sayısal analiz

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