Exhaust gas recirculation with highly oxygenated fuels in gas turbines

Rosec, Žiga (author), Žvar Baškovič, Urban (author), Katrašnik, Tomaž (author), Seljak, Tine (author)

To achieve a near zero emission footprint of combustion in power generation, introduction of fuels with low global warming potential, namely low-carbon or carbon neutral fuels and simultaneous reduction of harmful emissions through implementation of advanced combustion concepts is necessary. The study addresses this challenge experimentally by proposing a new approach which combines the benefits of highly oxygenated waste derived fuels, here represented by glycerol, and an introduction of external exhaust gasses recirculation (EGR) aimed for further reduction of NOx emissions. Thus, the recognized role of the high oxygen content in glycerol can positively influence the well-known penalties of EGR, which are commonly perceivable through elevated CO and soot emissions. The measurements were performed with an experimental gas turbine equipped with an exhaust heat regeneration system and feedback loop for 8% and 13% EGR content in compressor intake air. The proposed system layout represents a technically viable and cost-efficient approach for upgrading existent gas turbine setups with a goal to improve their emission footprint. Results confirm that with 8% and 13% EGR rate, NO [sub] x, CO and soot can be reduced simultaneously, thus improving the CO- NO [sub] x and soot- NO [sub] x trade off approximately 2-fold for each species. Additionally, underlying phenomena responsible for observed improvements while increasing EGR rate are identified as an increased soot reactivity, a competing effect of EGR related dilution and an increased primary air temperature together with spray related parameters linked to low stoichiometric ratio of glycerol.

• Language: English
• Keywords: oxygenated fuel, exhaust gas recirculation, biofuel, particulate matter, gas turbine, advanced combustion concepts
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Author Accepted Manuscript
• Submitted for review: 24.05.2020
• Article acceptance date: 29.05.2020
• Publication date: 15.10.2020
• Year: 2020
• Number of pages: Str. 1-12
• Numbering: Vol. 278, art. 118285
• PID: 20.500.12556/RUL-126919
• UDC: 621.438(045)
• ISSN on article: 0016-2361
• DOI: 10.1016/j.fuel.2020.118285
• COBISS.SI-ID: 20033539
• Publication date in RUL: 10.05.2021

Record is a part of a journal

• Title: Fuel
• Shortened title: Fuel
• Publisher: Elsevier
• ISSN: 0016-2361
• COBISS.SI-ID: 37399

Secondary language

• Language: Slovenian
• Keywords: oksigenirana goriva, recirkulacija izpušnih plinov, biogorivo, izpusti delcev, plinska turbina, napredni koncepti zgorevanja