NİTRİK ASİT ÜRETİMİNDE ENERJİ AKTARIM SÜRECİ VE PROSES GAZI AKIŞ MODELİ

Öz

Ostwald prosesinde, platin katalizörlüğünde amonyak, oksijenle reaksiyona sokularak oksitler meydana getirilir ve bunlar da aside dönüştürülür. Asitle yapılan nitrolama prosesleri endüstride önemli olup, bu yolla plastikler, boyalar ve patlayıcı maddeler gibi pek çok çeşit ürün elde edilir. Bu tür işletmelerde prosesler bazında enerji tüketiminin izlenmesiyle enerji tasarrufu sağlanması ve üretim reflekslerinin geliştirilmesi, mevcut proses akışlarının ve yapısının bir model üzerinden tanımlanarak, parametre değişimleri ile analizini gerektirmektedir. Bu çalışmada, bir nitrik asit üretim tesisinde amonyak oksidasyon reaktöründe elde edilen ve proses gazı olarak kullanılan NOx gazlarının enerji aktarım süreci ile prosesi etkileyen parametrelerin araştırılması yapılmış olup, verimliliği etkileyen parametreler belirlenmiştir. Tesisin enerji verimliliği göz önüne alınarak problemler ele alınmıştır. Amonyak oksidasyon reaktörü sistemin en önemli kısmıdır. Bu nedenle tesisteki eski reaktörlerin işletme parametreleri ile yerine revize edilen yeni reaktörlerin karşılaştırılması yapılmıştır. Revizyon sonrası eski ve yeni reaktörlerde sistemin verimliliği ile performansı incelenmiştir. Ayrıca yeni reaktörlerde mevcut proses gazının akışı ve hidrodinamik yapısı ANSYS Fluent programı yani CFD analizi ile incelenmiştir.

Anahtar Kelimeler

• Nitrik Asit Üretim Prosesi
• Amonyak Oksidasyon Reaktörü
• Proses Gazı
• Akış Modeli

Energy Transfer Process and Process Gas Flow Model in Nitric Acid Production

Öz

In the Oswald process, ammonia is reacted with oxygen under the catalyst of platinum to form oxides, which are converted into acid. Acid nitriding processes are essential in industry, and many kinds of products, such as plastics, paints, and explosives, are obtained this way. Achieving energy savings and improving production reflexes by monitoring energy consumption on a process basis in such enterprises requires defining the current process flows and structure through a model and analyzing them with parameter changes. In this study, the energy transfer process of NOx gases obtained in the ammonia oxidation reactor and used as process gas in a nitric acid production facility and the parameters affecting the process were investigated. The parameters affecting the efficiency were determined. The problems were addressed by considering the energy efficiency of the facility. The ammonia oxidation reactor is the most essential part of the system. For this reason, the operating parameters of the old reactors in the facility were compared with the revised new reactors. After the revision, the efficiency and performance of the system were examined in old and new reactors. In addition, the flow and hydrodynamic structure of the existing process gas in the new reactors were reviewed with the ANSYS Fluent program, that is, CFD analysis.

Anahtar Kelimeler

• Nitric Acid Production Process
• Ammonia Oxidation Reactor
• Process Gas
• Flow Model

Kaynakça

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