Anaerobic treatment of amoxycilin

Abstract

The pharmaceutical wastewaters contain a variety of organic and inorganic constituents including spent solvents, catalysts, additives, reactants and small amounts of intermediates and products, and may therefore be high in chemical oxygen demand (COD) It is estimated that approximately half of the pharmaceutical wastewaters produced worldwide are discarded without specific treatment. Recently there are specific studies reporting the application of anaerobic technology for the treatment of drug pharmaceutical wastewaters. However, the high COD concentration in such pharmaceutical wastewaters makes them potential candidates for anaerobic technology. The anaerobic process is very much favorable for toxic wastewater, where aerobic oxidation of organic matter would result in high-energy consumption and production of huge quantities of sludge. The most important merits of anaerobic treatment are the ability to treat toxic wastes, low energy input, low sludge yield, low nutrient requirement, low operating cost, low space requirement and net benefit of energy generation in the form of biogas. Modern anaerobic processes used for high rate reactors such as the UASB have been applied to the treatment of a wide variety of industrial wastewaters, increased disinfection of pathogenic organisms and eliminating the need of cooling for effluent of high temperature. The occurrences of several kinds of antibiotics like macrolides have been reported in many environmental samples such as municipal wastewater, surface water, groundwater, sludge and sediments. Antibiotics are often not metabolised completely in the human body after administration and are consequently excreted into the sewage system, which becomes the main route of emission of these compounds. The activities such as sewage, medical wastes, medicine production, food production and livestock production have created the sources of antibiotics. β-Lactam groups of antibiotics have a wide area of usage in human healthy and veterinary medicine and they have inhibitory effects on bacteria in the biological treatment systems. One of the most frequently used antibiotics in the world is amoxicillin. The effect of amoxicillin in human excrement on the biodegradation process of feces has been reported and it was found that although the concentration of amoxicillin in toilet matrix declined quickly, it seemed to be basically difficult to treat antibiotics in a bioreactor due to their inhibitory effect on bacteria. Since the delaying effect on the feces decomposition process was strong. Specially, Amoxycillin is a broad spectrum antibiotic. Generally, it is used for growing of livestock and their health (for Helicobacter pylori and Actinobacillus pleuropneumoniae to be killed) in veterinary and human healthy. Since the wastewater containing antibiotics have low BOD5/ COD ratios, it is thought that this ratio could be increased by using anaerobic multi-chamber bed reactor (AMCBR). Since the wastewater containing antibiotics have high inert COD ratios and recalcitrant organic matters, it is important to remove the slowly organic matters via acclimation of anaerobic microorganisms under anaerobic conditions in an AMCBR reactor system. In this study, the IC50 value for Amoxycillin is ascertained as 195 mg/L by using anaerobic granular sludge in anaerobic batch reactors. When Amoxycillin concentration is increased from 5 mg/L to 350 mg/L in batch operation, it is observed that SMA decreased from 1.2 gCH4-COD/gVSS.day to 0.18 gCH4-COD/gVSS.day. In ninth and tenth days of the operation period, without acclimation step, it is observed that COD removal efficiency reached to 70% the daily methane production was 9000 ml, while the percent of methane gas produced was 50% of the total gas It is observed that total volatile fatty acid (TVFA) concentrations decreased from the third chamber of the AMCBR to the first chamber of the AMCBR. The TVFA concentrations decreased from 500 mg/L to 120–140 mg/L in the third chamber of the anaerobic reactor. It was showed that the HCO3 alkalinity ranged 569–874 mg/L and TVFA/ HCO3 ratios ranged between 0.15 and 0.38. The amoxycillin concentrations decreased from 150 mg/L to 70 mg/L, after one weak of operation period without acclimation. The Amoxycillin removal efficiency was recorded as 53% after 9 and 19 days of operation period. Also, it is observed that The BOD5/COD ratio of wastewater containing Amoxycillin antibiotic increased from 0.05 to 0.25 after 10-20 days of anaerobic treatment in AMCBR reactor system.

Özet

Kanalizasyon, tıbbi atıklar, ilaç endüstrisi, gıda üretimi, çiftlik hayvanlarının üretimi gibi faaliyetler antibiyotiklerin kaynaklarını oluşturmaktadır. Antibiyotiklerden β-Laktam grubu olanlar insan sağlığında ve veterinerlikte çok geniş bir kullanım aralığına sahiptir. Özellikle Amoksisilin geniş spektrumlu bir etkiye sahiptir. Genellikle çiftlik hayvanlarının gelişimi ve sağlığı için (Helicobacter pylori ile Actinobacillus pleuropneumoniae’nin öldürülmesi) veterinerlikte ve özellikle insan sağlığında kullanılmaktadır. Antibiyotiklerin anaerobik koşullarda arıtılabilirliği ile yapılmış çok az sayıda çalışma bulunmaktadır. Antibiyotiklerin BOİ5/KOİ oranları düşük olduğundan bu oranın Anaerobik Çok Kademeli Yatak Reaktör (AÇKYR) kullanarak yüksek değerlere çıkarılması düşünülmektedir. Genelde antibiyotik içeren atık suların inert KOİ oranları ve zor ayrışan organik madde düzeyleri yüksektir. Bu nedenle zor ayrışan organik maddenin anaerobik koşullarda aklimasyon ile mikroorganizmalar tarafından alınmasını sağlamak önemlidir. Bu çalışmada serum şişelerinde anaerobik granül çamur kullanılarak Amoksisilin için IC50 değeri 195 mg/L bulunmuştur. Anaerobik kesikli çalışmalarda Amoksisilin konsantrasyonu 5 mg/L’den 350 mg/L’ye arttırıldığında SMA’nın 1.2 gCH4-KOİ/gUAKM.gün’den 0.18 gCH4-KOİ/gUAKM.gün’e düştüğü gözlenmiştir. Aklimasyon safhası olmadan işletme periyodunun 9 ve 10. gününde KOİ giderim veriminin % 70’e çıktığı ve sabit kaldığı, metan üretiminin 9000 ml, metan yüzdesinin de % 50 olduğu gözlenmiştir. TUYA miktarlarının 1.Hazneden 3.Hazneye geçişte azaldığı ve TUYA konsantrasyonlarının 500 mg/L’den 120–140 mg/L’ye düştüğü gözlenmiştir. 1.Haznede pH’ın 6.98 olduğu çıkışta ise pH değerlerinin arttığı (7.55) gözlenmiştir. HCO3 alkalinitesinin 569–874 mg/L arasında olduğu ve TUYA/ HCO3 oranının 0.15-0.38 arasında olduğu gözlenmiştir. Amoksisilin konsantrasyonu reaktör işletilmesinin 9 ve 19. günlerinde 150 mg/L’den 70 mg/L’ye düştüğü yani % 53 oranlarında arıtma verimi ile giderildiği gözlenmiştir. Amoksisilin içeren atıksuyun BOİ5/KOİ oranının anaerobik arıtma sonrası 0.05’ten 0.25’e yükseldiği gözlenmiştir.