Physico-Chemical Treatment of Dairy Industry Wastewaters: A Review

Dairy industries have grown in most countries because of the demand in milk and milk products. This rise has led to the growth of dairy industries. The wastewaters discharged from this industry contain high concentrations of nutrients, chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS) and organic and inorganic contents, which can cause serious environmental problems if not properly treated. The conventional biological treatment methods are suitable for dairy wastewaters due to its high biodegradability. However, long chain fatty acids formed during the hydrolysis of lipids show the inhibitory action during anaerobic treatment. Sequencing batch reactor (SBR) and up flow anaerobic sludge blanket (UASB) systems seem to be the most promising technology for the biological treatment of dairy wastewaters. Several research papers have been published on the application of aerobic and anaerobic treatment technologies for dairy industry wastewater, but both treatment methods still have some disadvantages. The most important challenge is to find cost-efficient and environmentally sustainable approaches to enable water reuse and waste management. Therefore, alternative treatment technologies against biological treatment methods such as coagulation, adsorption, membrane and electrolysis processes are under investigation. This chapter provides a critical review focusing on physicochemical treatment technologies of dairy wastewater

Treatment of Antibiotics in Wastewater Using Advanced Oxidation Processes (AOPs)

Antibiotics are nonbiodegradable, can survive at aquatic environments for long periods and they have a big potential bio-accumulation in the environment. They are extensively metabolized by humans, animals and plants. After metabolization, antibiotics or their metabolites are excreted into the aquatic environment. Removal of these compounds from the aquatic environment is feasible by different processes. But antibiotics are not treated in conventional wastewater treatment plants efficiently. During the last years studies with advanced oxidation processes (AOPs) for removal of these pharmaceuticals from waters has shown that they can be useful for removing them fully. Advanced oxidation processes (AOPs) can work as alternatives or complementary method in traditional wastewater treatment, and highly reactive free radicals, especially hydroxyl radicals (OH) generated via chemical (O3/H2O2, O3/OH-), photochemical (UV/O3, O3/H2O2) reactions, serve as the main oxidant. This study presents an overview of the literature on antibiotics and their removal from water by advanced oxidation processes. It includes almost all types of antibiotics which are consumed by human and veterinary processes. It was found that most of the investigated advanced oxidation treatment processes for the oxidation of antibiotics in water are direct and indirect photolysis with the combinations of H2O2, TiO2, ozone and Fenton?s reagent

Investigation of electrochemical ozone generation and its applications by using new catalysts

Bu çalışmada, yeni nesil elektrokatalistler ile hazırlanan anot materyali ile elektrokimyasal olarak ozon üretiminin incelenmesi ve bu yeni anotlarla çeşitli endüstriyel atıksuların anodik oksidasyonunun incelenmesi amaçlanmıştır. Anot üretimi laboratuvar ortamında, titanyum örgü üzerine antimon, kalay, nikel ve antimon, kalay, kobalt kaplanarak hazırlanmıştır. Bu elektrotların elektrokimyasal ozon üretimindeki potansiyeli incelenmiştir. Elektrotlar daldırma ve piroliz yöntemiyle kaplanmıştır. Sn:Sb:Ni ve Sn:Sb:Co kaplama solüsyonları 500:8:1 molar oranında optimize edilmiştir. Bu kompozisyonda, nikel kaplı elektrotlar için %33 ve kobalt kaplı elektrotlar için %35 oranlarında toplam elektrokiyasal ozon üretimi için akımsal verimlilik değerleri ölçülmüştür. Uygulanan voltaj ve akımsal yoğunluğun, akımsal verimlilik üzerine etkisi ve enerji tüketim oranları incelenmiştir. Ni/Sb– SnO2 ve Co/Sb – SnO2 kaplı anotlar tekstil ve süt endüstrisi atıksuyunu arıtmak için kullanılmıştır. Tekstil atıksularında nikel kaplı anot materyali için optimum şartlarda (7,2 pH, 1 g/L NaCl ve 50 mA/cm2 akımsal yoğunluk) % 100 renk ve %91 KOİ giderim verimleri kobalt kaplı anot materyali için 7 pH, 1 g/L tuzluluk ve 50 mA/cm2 akımsal yoğunluk değerlerinde %100 renk ve %90 KOİ giderim verimleri elde edilmiştir. Yine aynı şekilde süt endüstrisi atıksularında da çalışmalar yürütülmüştür. Süt endüstrisi atıksuları yağlı içeriğin giderimi amacı ile asit kraking işlemine tabi tutulduktan sonra anodik oksidasyona tabi tutulmuş ve nikel kaplı anot materyali için 4 pH, 1 g/L tuzluluk ve 50 mA/cm2 akımsal yoğunluk değerlerinde %98 KOİ giderim verimi elde edilmiştir. Kobalt kaplı anot materyali için 7 pH, 1,5 g/L tuzluluk ve 50 mA/cm2 akımsal yoğunluk değerlerinde %98 KOİ giderim verimi elde edilmiştir.In this study, investigation of electrochemical ozone generation by anodic material which prepared by novel electrocatalysts and observation of the anodic oxidation of various industrial wastewaters with these new anodes were aimed. The anode material was prepared in laboratory environment by dip coating antimony and nickel doped tin dioxide on titanium substrate. The potential of electrochemical ozone generationof these anodes was observed. The electrode was prepared by the dip-coating and pyrolysis method. The tin, antimony and nickel composition in the precursor coating solution was optimized to be Sn: Sb: Ni = 500: 8: 1 (molar ratio) the tin antimony and cobalt composition was also optimized to Sn:Sb:Co 500:8:1. With the optimized composition, for nickel doped electrodes 33% total current efficiency was achieved and for cobalt doped electrodes %35 current efficiency was achieved for ozone generation. The effect of applied voltage on current efficiency, current densities, power consumption rate were discussed. Ni/Sb – SnO2 and Co/Sb – SnO2 anodes were used to investigate their efficiency in treating textile and dairy industrial wastewater. For nickel doped anodic material in optimum conditions (pH:7,2, 1 g/L NaCl, 50 mA/cm2 current density) 100% color and 91% COD treatment and for cobalt doped anodic material in optimum conditions (7 pH, 1 g/L NaCl ve 50 mA/cm2 current density) 100% color and 90% COD treatment were achieved in textile industry wastewater. Because of oily content anodic oxidation was applied after acid cracking for dairy industry wastewater and for nickel doped anodic material in optimum conditions (pH:4, 1 g/L NaCl, 50 mA/cm2 current density and 91% COD treatment and for cobalt doped anodic material in optimum conditions (pH:7, 1,5 g/L NaCl ve 50 mA/cm2 current density) and 98% COD treatment were achieved in dairy industry wastewater. Ozone, Electrochemical ozone generation, Electrolysis, wastewater treatmen

A survey on nitrogen and phosphorus removal by constructed wetlands and other treatment systems

Bu çalışmada evsel ve endüstriyel atıksularda bulunan ve ötrofikasyona neden olan azot ve fosfor elementlerinin giderimi için kullanılan yöntemler araştırılmıştır. Çalışmanın asıl amacı, genel olarak sistemin kurulabilmesi için gerekli şartların belirlenmesi ve yapay sulakalan sisteminin bir köye uygulanmasıdır.Sistem kurulumunda 500 kişilik bir köy için bir uygulama yapılmıştır. Önce debi hesaplanmış, kirlilik yükleri belirlenmiş, sızdırmazlık sağlanmış ve Typha Latifolia sulakalan bitkisi vasıtasıyla arıtma yapılacak şekilde tasarım tamamlanmıştır.Sistem tasarımında "Su Kirliliği Kontrol Yönetmeliği Tablo 21.5"de bulunan AKM=150 mg/l, BOİ = 50 mg/l limit değerleri esas alınmıştır. Çalışma sonucunda projelendirilen sistemde yasal değerler teorik olarak sağlanmıştır.In this study, removal of nitrogen and phosphorus, which can be found in domestic and industrial wastewater and cause eutrofication, is examined. The aim of this study is to determine how to found constructed wetland systems in general and implementation of a constructed wetland to a village.Implementation is performed on a village of 500 people. First, the flow of wastewater is calculated, then pollution loadings are determined, basin is formed by impermeable substrate and the design is completed such that wastewater is treated using Typha Latifolia which is a type of constructed wetland plant.In the system project, 150 mg/l for TSS and 50 mg/l for BOD5 pollution charges of effluent water are accepted as values of limit.The system projected at the end of study is theoretically within the limits of the legal standards of wastewater discharge