Jeotermal enerji kullanılarak sıvı hidrojen üretimi için geliştirilen ORC destekli çok fonksiyonlu bir sistemin modellenmesi, termodinamik optimizasyonu ve eksergoekonomik analizi
Loading...
Date
2020-12-31
Authors
Bademlioğlu, Ali Hüsnü
Journal Title
Journal ISSN
Volume Title
Publisher
Bursa Uludağ Üniversitesi
Abstract
Bu çalışmada, sıvı hidrojen üretimi için geliştirilen jeotermal enerji kaynaklı ve alt modül olarak sırasıyla ORC sistemi, yüksek sıcaklıklı elektroliz, absorbsiyonlu soğutma ve hidrojen sıvılaştırma çevrimlerinden oluşan kapsamlı, çok fonksiyonlu bir sistem modellenmiş, modellenen sistemin termodinamik optimizasyonu ve eksergoekonomik analizleri gerçekleştirilmiştir. Sıvı hidrojen üretimi için modellenen sistemin termodinamik performansı ORC sistemlerinde kullanılan farklı soğutucu akışkanlar (R123, R245fa, R601, n-Hexane) için farklı buharlaştırıcı sıcaklıklarında (100⁰C-150⁰C) incelenmiştir. Ayrıca çalışma kapsamında farklı sıvılaştırma çevrimleri ve absorbsiyonlu soğutma sisteminde kullanılan eriyik çiftleri dikkate alınarak hidrojen üretim sistemi için altı farklı model oluşturulmuştur. Modellerin enerji ve ekserji analizleri gerçekleştirilmiş, sıvı hidrojen üretim performansları karşılaştırılmış ve sistem için optimum çalışma parametreleri belirlenmiştir. Optimum çalışma şartları için eksergoekonomik analizler gerçekleştirilmiş ve sistemi oluşturan komponentlerin eksergoekonomik performansları değerlendirilmiştir. Oluşturulan tüm modeller birlikte ele alındığında, ön soğutmalı Claude sıvılaştırma sisteminin kullanıldığı ve absorbsiyonlu soğutma çevriminde NH3-H2O eriyik çiftinin tercih edildiği Model 2’nin termodinamik performansının diğer modellere kıyasla daha yüksek olduğu ve hidrojen üretim miktarı açısından ise daha kullanılabilir olduğu belirlenmiştir. Sabit çalışma şartlarında, soğutucu akışkan ve buharlaştırıcı sıcaklığına bağlı olarak Model 2’de üretilen hidrojen miktarı maksimum 0,18049 kg/s olarak hesaplanmış, enerji ve ekserji verimi ise sırasıyla maksimum %11,56 ve %35,09 olarak belirlenmiştir. 150⁰C buharlaştırıcı sıcaklığı ve n-Hexane için Model 2’nin eksergoekonomik analizleri gerçekleştirilmiş ve elektroliz ünitesi 441,206 USD/h ile en yüksek yatırım maliyetine sahip komponent olmuştur. Ayrıca sistemde, ekserji yıkım maliyeti en yüksek olan komponentin 61,206 USD/h maliyet ile Claude sıvılaştırma sistemindeki (2) numaralı eşanjör olduğu belirlenmiştir. Sıvılaştırılan hidrojenin birim ekserji maliyeti 11,277 USD/GJ olarak hesaplanmıştır.
In this study, a comprehensive, multifunctional system consisting of ORC system, high temperature electrolysis system, absorption refrigeration system and hydrogen liquefaction system, developed for liquid hydrogen production, aided from geothermal energy, was modeled and thermodynamic optimization and exergoeconomic analyzes of the modeled system were performed. The thermodynamic performance of the system modeled for liquid hydrogen production was investigated at different evaporator temperatures (100⁰C-150⁰C) for different refrigerants (R123, R245fa, R601, n-Hexane) used in ORC systems. In addition, within the scope of the study, six different models were created for the hydrogen production system by considering the different liquefaction cycles and the solution pairs used in the absorption refrigeration system. Energy and exergy analyze of the models were performed, liquid hydrogen production performances were compared, and optimum operating parameters were determined for the system. Exergoeconomic analysis were performed for optimum operating conditions, and the exergoeconomic performances of the components that made up the system were evaluated. Considering all created models, it was determined that the thermodynamic performance of Model 2, in which the precooled Claude liquefaction system is used and the NH3-H2O solution pair is preferred in the absorption refrigeration cycle, was higher than the other models and more usable in terms of the amount of hydrogen production. Under constant operating conditions, the amount of hydrogen produced in Model 2 depending on the refrigerant and evaporator temperature was calculated as maximum 0,18049 kg/h, the energy and exergy efficiency was determined as 11,56% and 35,09% respectively. Exergoeconomic analysis of Model 2 for 150⁰C evaporator temperature and n-Hexane was performed and the electrolysis unit became the component with the highest investment cost with 441,206 USD/h. Furthermore, it was determined that the component with the highest exergy destruction cost in the system was the heat exchanger (2) in the Claude liquefaction system with a cost of 61,206 USD/h. The unit exergetic cost of liquefied hydrogen was calculated as 11,277 USD/GJ.
In this study, a comprehensive, multifunctional system consisting of ORC system, high temperature electrolysis system, absorption refrigeration system and hydrogen liquefaction system, developed for liquid hydrogen production, aided from geothermal energy, was modeled and thermodynamic optimization and exergoeconomic analyzes of the modeled system were performed. The thermodynamic performance of the system modeled for liquid hydrogen production was investigated at different evaporator temperatures (100⁰C-150⁰C) for different refrigerants (R123, R245fa, R601, n-Hexane) used in ORC systems. In addition, within the scope of the study, six different models were created for the hydrogen production system by considering the different liquefaction cycles and the solution pairs used in the absorption refrigeration system. Energy and exergy analyze of the models were performed, liquid hydrogen production performances were compared, and optimum operating parameters were determined for the system. Exergoeconomic analysis were performed for optimum operating conditions, and the exergoeconomic performances of the components that made up the system were evaluated. Considering all created models, it was determined that the thermodynamic performance of Model 2, in which the precooled Claude liquefaction system is used and the NH3-H2O solution pair is preferred in the absorption refrigeration cycle, was higher than the other models and more usable in terms of the amount of hydrogen production. Under constant operating conditions, the amount of hydrogen produced in Model 2 depending on the refrigerant and evaporator temperature was calculated as maximum 0,18049 kg/h, the energy and exergy efficiency was determined as 11,56% and 35,09% respectively. Exergoeconomic analysis of Model 2 for 150⁰C evaporator temperature and n-Hexane was performed and the electrolysis unit became the component with the highest investment cost with 441,206 USD/h. Furthermore, it was determined that the component with the highest exergy destruction cost in the system was the heat exchanger (2) in the Claude liquefaction system with a cost of 61,206 USD/h. The unit exergetic cost of liquefied hydrogen was calculated as 11,277 USD/GJ.
Description
Keywords
ORC, Jeotermal, Hidrojen, Enerji, Ekserji, Eksergoekonomik, Sistem, Geothermal, Hydrogen, Energy, Exergy, Exergoeconomic, System
Citation
Bademlioğlu, A. H. (2020). Jeotermal enerji kullanılarak sıvı hidrojen üretimi için geliştirilen ORC destekli çok fonksiyonlu bir sistemin modellenmesi, termodinamik optimizasyonu ve eksergoekonomik analizi. Yayınlanmamış doktora tezi. Bursa Uludağ Üniversitesi Fen Bilimleri Enstitüsü.