Effect of Ionization-Assisted Electrochemical Aeration on Wastewater Treatment Performance

Öz

In this study, the effect of an ionization-assisted electrochemical aeration system on wastewater treatment performance was experimentally investigated. Experiments were conducted using raw wastewater samples obtained from the Yeniköy (Gölcük) Wastewater Treatment Plant, and samples were collected at specific time intervals during a 60 min aeration period for each system. System performance was evaluated in terms of temperature, dissolved oxygen, chemical oxygen demand, biochemical oxygen demand, total suspended solids, phosphate, and total nitrogen. The obtained results demonstrated that the ionization-assisted electrochemical aeration system achieved higher dissolved oxygen concentrations than the conventional compressor aeration system. Dissolved oxygen concentrations reached 4.24 mg/L in the electrochemical aeration system and 5.40 mg/L in the hybrid system. The hybrid system exhibited the highest chemical oxygen demand removal performance with a removal efficiency of 70.4%, whereas the electrochemical aeration system achieved 54.1% chemical oxygen demand removal. Approximately 50.5% reduction in biochemical oxygen demand was observed in the hybrid system. Phosphate removal reached approximately 88.5% in the electrochemical system and 98.0% in the hybrid system; however, this high removal was likely influenced substantially by aluminum-induced electrocoagulation and precipitation in addition to the aeration process. Similar total nitrogen removal efficiencies were observed in all systems, with approximately 47% removal. The ionization-assisted electrochemical aeration system and hybrid aeration systems also resulted in higher wastewater temperatures than the conventional compressor aeration system. An increase in total suspended solids concentrations was observed in the ionization-assisted electrochemical and hybrid systems, which may be associated with intensive mixing, floc disruption, and particle resuspension. Overall, the ionization-assisted electrochemical and hybrid aeration systems resulted in higher dissolved oxygen concentrations and improved removal of several measured pollutants compared with conventional compressor aeration.

Anahtar Kelimeler

• Electrochemical aeration
• ionization
• wastewater treatment
• dissolved oxygen
• phosphate removal

Etik Beyan

Compliance with Ethical Standard a) Author Contributions 1. M.B.B: Conceptualization, Investigation, Data Curation, Formal analysis, Methodology, 2. M.K.: Methodology, Investigation; Validation, 3. K.E.: Writing—review and editing. The published version of the manuscript has been read and approved by both authors. b) Conflict of Interests There is no conflict of interest, according to the authors. c) Statement on the Welfare of Animals Not relevant, d) Statement of Human Rights There are no human subjects in this study. e) Declaration of Not Using AI The authors declare that they have not used any form of generative artificial intelligence in the writing of this article, or in the creation of visuals, graphs, tables, or their corresponding headings.

İyonizasyon Destekli Elektrokimyasal Havalandırmanın Atıksu Arıtım Performansına Etkisi

Öz

Bu çalışmada, iyonizasyon destekli elektrokimyasal havalandırma sisteminin atıksu arıtma performansı üzerindeki etkisi deneysel olarak araştırılmıştır. Deneyler, Yeniköy (Gölcük) Atıksu Arıtma Tesisi'nden elde edilen ham atıksu numuneleri kullanılarak gerçekleştirilmiş ve her bir sistem için 60 dakikalık havalandırma süresi boyunca belirli zaman aralıklarında numuneler alınmıştır. Sistem performansı; sıcaklık, çözünmüş oksijen, kimyasal oksijen ihtiyacı, biyokimyasal oksijen ihtiyacı, toplam askıda katı madde, fosfat ve toplam azot parametreleri üzerinden değerlendirilmiştir. Elde edilen sonuçlar, iyonizasyon destekli elektrokimyasal havalandırma sisteminin geleneksel kompresörlü havalandırma sistemine kıyasla daha yüksek çözünmüş oksijen konsantrasyonlarına ulaştığını göstermiştir. Çözünmüş oksijen konsantrasyonları elektrokimyasal havalandırma sisteminde 4,24 mg/L'ye ve hibrit sistemde 5,40 mg/L'ye ulaşmıştır. Hibrit sistem %70,4'lük giderim verimliliği ile en yüksek kimyasal oksijen ihtiyacı giderim performansını göstermiş; buna karşılık elektrokimyasal havalandırma sistemi %54,1 oranında kimyasal oksijen ihtiyacı giderimi sağlamıştır. Hibrit sistemde biyokimyasal oksijen ihtiyacında yaklaşık %50,5 oranında azalma gözlenmiştir. Fosfat giderimi elektrokimyasal sistemde yaklaşık %88,5 ve hibrit sistemde %98,0 seviyesine ulaşmıştır; ancak bu yüksek giderimin havalandırma prosesine ek olarak alüminyum kaynaklı elektrokoagülasyon ve çöktürmeden önemli ölçüde etkilenmiş olması muhtemeldir. Toplam azot gideriminde ise tüm sistemlerde benzer sonuçlar gözlenmiş ve yaklaşık %47 seviyesinde giderim sağlanmıştır. İyonizasyon destekli elektrokimyasal havalandırma sistemi ve hibrit havalandırma sistemleri, geleneksel kompresörlü havalandırma sistemine kıyasla daha yüksek atıksu sıcaklıklarına da neden olmuştur. İyonizasyon destekli elektrokimyasal ve hibrit sistemlerde toplam askıda katı madde konsantrasyonlarında bir artış gözlenmiş olup, bu durum yoğun karıştırma, flok yapısının bozulması ve partiküllerin yeniden süspanse olması ile ilişkilendirilebilir. Sonuç olarak, iyonizasyon destekli elektrokimyasal ve hibrit havalandırma sistemleri, geleneksel kompresörlü havalandırmaya kıyasla daha yüksek çözünmüş oksijen konsantrasyonları ve ölçülen çeşitli kirleticilerin gideriminde iyileşme sağlamıştır.

Anahtar Kelimeler

• Elektrokimyasal havalandırma
• iyonizasyon
• atıksu arıtımı
• çözünmüş oksijen
• fosfat giderimi

Etik Beyan

Etik Standartlara Uyum Yazar Katkıları 1. MBB: Kavramsallaştırma, Araştırma, Veri Kürasyonu, Biçimsel analiz, Metodoloji, 2. M.K.: Metodoloji, Araştırma; Onaylama, 3. K.E.: Yazma—inceleme ve düzenleme. El yazmasının yayımlanan versiyonu her iki yazar tarafından okunmuş ve onaylanmıştır. Çıkar Çatışması Yazarlara göre çıkar çatışması yoktur. c) Hayvanların Refahı Bildirisi İlgili değil, d) İnsan Hakları Beyanı Bu çalışmada insan denek yok. e) Yapay Zeka Kullanmama İdkanı Yazarlar, bu makalenin yazılışında veya görseller, grafikler, tablolar veya ilgili başlıklar oluşturulurken herhangi bir üretken yapay zeka kullanmadıklarını belirtmektedir.

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