Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, ENERJİ SİSTEMLERİ MÜHENDİSLİĞİ ANA BİLİM DALI, Turkey
Approval Date: 2022
Thesis Language: Turkish
Student: Sezgin TAŞDEMİR
Supervisor: Serhat Karyeyen
Open Archive Collection: AVESIS Open Access Collection
Abstract:
In the world, which is facing a global threat due to the ever-increasing energy need, the
energy resources should be used efficiently. Although coal reserves, which are fossil fuels,
are abundant in our country, it may not be convenient to use coal directly due to the
difficulty of transportation, the cost of combustor, and the excess of post-combustion
pollutant emissions. Since the gaseous fuels, which have easier combustion conditions,
have lower pollutant emission values, the by-product coke oven gas obtained from the
coking of the solid fuel coal was used in this study. The coke oven gas was consumed in a
burner with a thermal power of 10 kW, at conditions of excess air coefficient λ = 1,2. In
addition, the premixed burner, which increases the air-fuel mixture more and reduces the
dynamic pressure changes compared to the non-premixed burner, is consumed as premixed
fuel in this study, with the expectation that it will reduce the NO emission level and
combustion noise after combustion. In terms of being more economical and energy
efficient, using combustion simulations can guide new findings. For this purpose, the
experimental setup was modeled in three dimensions with a commercial CFD code. The
Eddy Dissipation Concept combustion model integrates 162-step reactions created with the
help of GRI-Mech 3.0 chemical kinetics. Standard k-Ɛ turbulence model and P-1 radiation
model were also included in the system, and the temperature and NO values after
combustion were compared with the experimental results and a good similarity was
achieved. Against the expectation that the coke oven gas containing high H2 will generate
high NOX during combustion, the colorless distributed combustion method has also been
examined. While applying this method, the temperature distribution, NO, CO and CO2
emissions after combustion were investigated by increasing the N2 or CO2 diluents so that
the O2 ratio in the air would decrease from 21%. In the results, it was observed that lower
maximum temperature and more homogeneous thermal field were obtained, and there was
a significant decrease in NO levels. It was concluded that using CO2 as a diluent is more
effective in terms of temperature distribution and NO reduction, while dilution with N2 is
more effective in terms of CO reduction.
Key Words : C oke oven gas, colorless distributed combustion, premixed burner,
computational fluid dynamics