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Due to their potential environmental risk, the abatement of organic micropollutants from wastewater has gained increasing attention in recent years. This thesis evaluates the use of ozone in Swedish wastewater treatment plants (WWTPs) and the incentives for full-scale implementation of organic micropollutant removal.This work is divided into two sections: the first segment comprises quantitative research of the removal of organic micropollutants using ozone, and the second discusses a qualitative study on the drivers of full-scale implementation of quaternary treatment in Swedish WWTPs.Ozone oxidation of organic micropollutants was examined in Sweden, taking country-specific conditions into consideration. This technology was implemented on a pilot scale on site at a total of 14 WWTPs, and its influence on the removal rates of organic micropollutants was determined by ozone dose, hydraulic retention time (HRT), water temperature, pH, concentration of organic matter, and prior treatment level (high- or low-loaded activated sludge and post-precipitation).The results from the first section demonstrate that ozonation is a suitable technology for Swedish conditions. In general, a slightly higher ozone dose was needed, compared with reported values, and a shorter HRT (7 min) can be applied without altering the removal efficiency. Nitrogen removal was not a prerequisite for efficient removal of organic micropollutants, and the evaluation of ozone dose was similar, whether based on dissolved organic carbon (DOC) or chemical oxygen demand (COD).The second section indicates that two of the most prominent drivers were proactivity with regard to possible treatment requirements and the desire to protect receiving waters. There were also aspirations to increase general knowledge of organic micropollutants and the role of WWTPs in the release of these into the environment.

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, Çevre Mühendisliği Ana Bilim Dalı, Kağıt endüstrisi, birçok gelişmiş ve gelişmekte olan ülkenin ekonomisinde önemli bir rol oynamaktadır. Bununla birlikte, suyu kirleten endüstrilerin başlıcılarından bir tanesi kağıt endüstrisidir. Kağıt endüstrisi yüksek su tüketimi ve üretim sonucu oluşan düşük biyolojik olarak parçalanamayan ve yüksek askıda katı madde miktarı ile tanımlanır. Kağıt sanayi atık sularının arıtımında biyolojik arıtma sıklıkla kullanılır. Hem biyolojik parçalanabilirliğinin çok düşük olması hem de atık suyun geri kazanımı için ileri arıtımın şart olduğu görülmektedir. Gelişmiş arıtma süreçleri arasında, membran teknolojisi bu amaçla kağıt fabrikası atık sularını arıtmak için iyi bir alternatif sunar. Bu çalışmada, membran süreçlerinin ham atık suya direkt uygulanması gerçekleştirilmiştir. Balıkesir Varaka Kağıt sanayi fabrikasından alınan atık suya seramik membran modülü entegre edilmiş çapraz akış ultrafiltrasyon ünitesinde direkt arıtımı uygulanmıştır. Askıda katı madde giderimi açısından çapraz akışlı membran sistemleri oldukça başarılı olabilmektedir. Giriş KOİ konsantrasyonu 5756 mg/L AKM konsantrasyonu ise 2233,3 mg/L olan atık su 200 nm por çapı ve 0,043314 m2 yüzey alanına sahip membran ünitesinden çapraz akış modda süzülmüştür. Sistemden %45 ortalama KOİ giderimi %100 AKM giderimi elde edilmiştir. 2,32 m/sn çapraz akış hız, 3 bar transmembran basıncı altında 30 ºC sıcaklıkta ve 1000 mg/L AKM konsantrasyonunda 415 L/m2 *sa limit akı değerine ulaşılmıştır. Çalışmada membran sisteminin tek başına oldukça yüksek verimde KOİ giderimi yaptığı tespit edilmiştir., Paper industry plays an important role in the economy of many developing and developed countries. Besides that, paper industry is one of the heavy water polluting industries. Paper industry is defined with high water consumption and high suspended solids amount high and non-biodegradable content. Biological wastewater treatment is used frequently for paper industry waste water. For both facts that biological degradability is too low and for of wastewater, advanced treatment is a pre-condition. Among all the treatment processes developed, membrane technology is a good alternative to treat paper industry waste water. In this study, a direct application of membrane processes has been applied to raw paper industry wastewater. Ceramic membrane module has been used on wastewater received from Balikesir Varaka Paper industry factory and direct filtration has been made on cross flow ultrafiltration unit. In terms of suspended solids cross flow membrane systems can be very successful. Raw wastewater (COD 5756 mg/L and SS 2233,3 mg/L) has been filtered in cross flow membrane module (200 nm por dimension and 0,044314 m2 membrane surface area). 45% average COD and 100% SS removal has been achieved from the system. At 2,32 m/second cross flow speed, under 3 bar transmembrane pressure, 30 ºC wastewater temperature and 1000 mg/L SS concentration, 415 L/m2 *h limit flux value has been reached. In this study it has been determined that membrane systems had a rather high performance of COD removal alone.

Heavy metal polluted wastewater from industries is currently one of the major environmental concerns leading to insufficient supply of clean water. Several strategies have been implemented to overcome this challenge including the use of microalgae as heavy metal bio-removers. However, there are still limitations that prevent microalgae to function optimally. Synthetic biology is a new biological discipline developed to solve challenging problems via bioengineering approaches. To date, synthetic biology has no universally affirmed definitions; however, it is uncontroversial that synthetic biology utilizes a constructive library of genetic standardized parts to create new biological systems or to redesign existing ones with improved characteristics. In this mini-review, we present state-of-the-art synthetic biology-based approaches that can be used to enhance heavy metal bio-removal from wastewater effluents by microalgae with a narrative synthetic biology workflow (Design-Build-Test-Learn cycle) to guide future developments of more advanced systems. We also provide insights into potent genes and proteins responsible for the bio-removal processes for stepwise developments of more advanced systems. A total of 49 unique genes and proteins are listed based on their eight heavy metals (Mn, Fe, Cu, Zn, As, Cd, Hg, and Pb) bio-removal functions in transport system, cellular tolerance, synthesis of key players in heavy metal bio-removal, biotransformation of heavy metals, and gene expression regulation. Thus, with our library, genetic parts are ready to be recruited for any synthetic biology-based designs. Thereby, this mini-review identifies potential avenues of future research and maps opportunities to unleash more potential of microalgae as heavy metal bio-removers with synthetic biology.

The growing accumulation of emerging contaminants in the environment can cause direct and indirect water pollution that puts human lives at risk. The fact that these contaminants are not or cannot be eliminated from the municipal water utilities, poses a significant concern. Researchers are currently pulling massive attention to improve existing technologies, develop new strategies and provide environmentally and durable solutions to mitigate water contamination problems. Adsorption and photodegradation are two of the most sustainable technologies that are used in water purification. These technologies have many advantages because of the economic, simple and easily operated designs needed to treat wastewater. Within these applications, metal organic frameworks (MOFs) are playing a significant role as novel class of porous materials characterized by a crystalline structure. MOFs are considered good candidates to be employed in wastewater treatment technologies because of the tunability of their features. The scope of this review article is to provide a comprehensive description of the recent studies published in the literature about the adsorptive and photocatalytic use of MOFs for the removal of organic emerging contaminants from wastewater. Furthermore, this study briefly highlights the synthesis technologies of MOFs. Finally, future perspective, and challenges associated with MOFs large scale production are discussed.

Wool and wastewaters from scouring can be a mixed blessing – a useful technological raw material or an environmental problem. If wool is scoured with no control, as the case most often is in Croatia, the wastewater released could endanger the environmental stability of the existing water systems. Since the interest has been growing recently for processing domestic wool, which also presents a considerable hazard of polluting water because of unskilled scouring and uncontrolled wastewater release into the natural water flows, we have organized investigations aimed at determining potentially dangerous ecological loads on the Croatian water systems, caused by scouring domestic wool. The results obtained indicate that improper disposal of the wool and/or uncontrolled release of wastewater from scouring present a considerable environmental hazard. We have concluded that impacts on the environment of scouring domestic wool in Croatia are the same as impacts on the environment obtained by normal functioning of a town of 1700– 2000 inhabitants.