Occurrence and removal of emerging contaminants in wastewaters

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Over the past decade, the occurrence and removal of emerging contaminants in the environment has received much attention. Both natural and synthetic progestogens, which are hormones, and also benzotriazoles are two examples of such emerging contaminants. Sewage treatment works are recognised as one of the main routes of these compounds to the environment. Low concentrations (nanograms per litre) of biologically active chemicals may exhibit an impact on aquatic organisms and human health. This study was undertaken to determine the occurrence and removal of these two classes of chemicals at sewage treatment works, along with an evaluation of the performance of advanced treatment and also to investigate their fate in the aquatic environment. Therefore, field-based sampling campaigns were undertaken at a sewage treatment works, rivers and potable water to achieve these aims. Solid phase extraction and LC/MS/MS were used in order to analyse the samples from these different locations, along with catchment modelling and assessment of how the use of benzotriazoles may contribute to their presence in the environment. The results have demonstrated that progestogens and benzotriazoles are in the sewage system; the natural hormone (progesterone) was the most predominant compound entering the sewage treatment work (46.9 ng/l) among the progestogens while concentrations of the benzotriazoles were two orders of magnitude higher than the progestogens. The conventional sewage treatment works were, to some extent, able to remove these compounds from wastewaters. However, this may not be adequate to afford protection to the environment. The investigation of advanced treatments, ozone, granular activated carbon and chlorine dioxide, indicated no further significant removal of progestogens, probably as a result of concentrations being close to method detection limits. However, there were indications that benzotriazoles were removed. A degradation study demonstrated that the natural hormone (progesterone) was degraded rapidly while benzotriazoles were not degraded. Catchment modelling indicated that high (up to 2,000 ng/l) concentrations of benzotriazoles would be present in surface waters used for potable supply, and consequently benzotriazoles were found in the tap water with mean concentrations of 30.9 ng/l (benzotriazole) and 15.1 ng/l for tolyltriazole. It is therefore apparent that although conventional treatment may be seen as effective, achieving over 90% removal, this may not be good enough. However, before investing in tertiary treatment, a number of factors, such as the effectiveness at different sites, the presence of degradation products and costs, both financial and in relation to energy use, need to be considered.Ministry of Higher Education and Scientific Research (IRAQ); Engineering and Physical Sciences Research Council (EPSRC) (UK); Severn Trent Water Ltd (UK

A review on induced mutagenesis of Stevia rebaudiana Bertoni

Stevia rebaudiana Bertoni in the Asteraceae family is commercially valuable and cultivated throughout the world due to the great demand for its steviol glycosides (SGs) contents particularly rebaudioside A. Previous studies confirmed that maximal content of SGs in stevia was achieved at or just before flowering, and delayed flowering with long days provide longer duration for steviol glycosides accumulation. However, there is no suitable stevia variety to be cultivated in Malaysia due to her short day length. Mutation induction, including gamma irradiation, had been shown to be useful for generating genetic variations as well as developing new plant varieties from which desired mutants were successfully selected. The use of mutagens, both physical and chemical, has helped in creating mutants that expressed the selected desirable traits. This paper presents some selected essential data available in extant scientific studies on stevia with the focus on application of gamma irradiation on stevia. Both established achievements and recent publications of gamma radiation on stevia were reviewed. Emphasis is on the exceptional potential of stevia through induced mutation approach especially by using gamma rays

A Review on Induced Mutagenesis of Stevia rebaudiana Bertoni

Stevia rebaudiana Bertoni in the Asteraceae family is commercially valuable and cultivated throughout the world due to the great demand for its steviol glycosides (SGs) contents particularly rebaudioside A. Previous studies confirmed that maximal content of SGs in stevia was achieved at or just before flowering, and delayed flowering with long days provide longer duration for steviol glycosides accumulation. However, there is no suitable stevia variety to be cultivated in Malaysia due to her short day length. Mutation induction, including gamma irradiation, had been shown to be useful for generating genetic variations as well as developing new plant varieties from which desired mutants were successfully selected. The use of mutagens, both physical and chemical, has helped in creating mutants that expressed the selected desirable traits. This paper presents some selected essential data available in extant scientific studies on stevia with the focus on application of gamma irradiation on stevia. Both established achievements and recent publications of gamma radiation on stevia were reviewed. Emphasis is on the exceptional potential of stevia through induced mutation approach especially by using gamma rays

Occurrence and removal of emerging contaminants in wastewaters

Over the past decade, the occurrence and removal of emerging contaminants in the environment has received much attention. Both natural and synthetic progestogens, which are hormones, and also benzotriazoles are two examples of such emerging contaminants. Sewage treatment works are recognised as one of the main routes of these compounds to the environment. Low concentrations (nanograms per litre) of biologically active chemicals may exhibit an impact on aquatic organisms and human health. This study was undertaken to determine the occurrence and removal of these two classes of chemicals at sewage treatment works, along with an evaluation of the performance of advanced treatment and also to investigate their fate in the aquatic environment. Therefore, field-based sampling campaigns were undertaken at a sewage treatment works, rivers and potable water to achieve these aims. Solid phase extraction and LC/MS/MS were used in order to analyse the samples from these different locations, along with catchment modelling and assessment of how the use of benzotriazoles may contribute to their presence in the environment. The results have demonstrated that progestogens and benzotriazoles are in the sewage system; the natural hormone (progesterone) was the most predominant compound entering the sewage treatment work (46.9 ng/l) among the progestogens while concentrations of the benzotriazoles were two orders of magnitude higher than the progestogens. The conventional sewage treatment works were, to some extent, able to remove these compounds from wastewaters. However, this may not be adequate to afford protection to the environment. The investigation of advanced treatments, ozone, granular activated carbon and chlorine dioxide, indicated no further significant removal of progestogens, probably as a result of concentrations being close to method detection limits. However, there were indications that benzotriazoles were removed. A degradation study demonstrated that the natural hormone (progesterone) was degraded rapidly while benzotriazoles were not degraded. Catchment modelling indicated that high (up to 2,000 ng/l) concentrations of benzotriazoles would be present in surface waters used for potable supply, and consequently benzotriazoles were found in the tap water with mean concentrations of 30.9 ng/l (benzotriazole) and 15.1 ng/l for tolyltriazole. It is therefore apparent that although conventional treatment may be seen as effective, achieving over 90% removal, this may not be good enough. However, before investing in tertiary treatment, a number of factors, such as the effectiveness at different sites, the presence of degradation products and costs, both financial and in relation to energy use, need to be considered.EThOS - Electronic Theses Online ServiceMinistry of Higher Education and Scientific Research (IRAQ)Engineering and Physical Sciences Research Council (EPSRC)Severn Trent Water LtdGBUnited Kingdo

Characterisation of Raw Sewage and Performance Evaluation of Al-Diwaniyah Sewage Treatment Work

Abstract These days, water and wastewater treatment are one of the most important issues regarding to the human health. Wastewaters are one of the most environmental pollutants and a wide range of adverse effects linked to the effect of untreated wastewaters or wastewaters that treat improperly. The aim of this present study was to evaluate performance of the wastewater treatment plant at Al-Diwaniyah City according to the national standards. Therefore, data of the most common parameters (PH, BOD 5 , COD, TSS, PO 4 , NO 3 , Cl, and Oil and Grease) were collected from the wastewater treatment plant. The study revealed that the wastewater treatment plant was receiving medium to strong influent with a BOD 5 /COD ratio of between (0.4 -0.7). Regression analysis was achieved to approximate the influent of BOD5 and TSS. While the effluent quality was exceeded the Iraq standards for disposing treated wastewater to the water bodies with a fluctuation in the ratio of BOD 5 to COD as a consequence of the operational problems. Therefore, these results would be of help to planners and policy makers in the City to combat such this problem and to take the necessary actions to reduce the impact of these pollutants

Assessment model of water harvesting and storage location using GIS and remote sensing in Al-Qadisiyah, Iraq

One of the important steps towards optimizing land productivity and water availability for the semi-arid and arid areas is the identification of potential sites for water harvesting. Therefore, this paper uses the Geographical Information System (GIS) techniques to select the optimized sites for water harvesting in Al-Qadisiyah Governorate, Iraq. Geographic water management capabilities are applied as a spatial analysis model. Data from global data repositories are retrieved followed by rescaling them to a spatial resolution to acquire a manageable input data set. The Soil Conservation Service Curve Number (SCS-CN) model is used to calculate the potential runoff as an intermediate input. Multi-Criteria Evaluation techniques are adopted to identify the relative importance and suitability levels of the input parameters set to manage the water supply. The suitability for identifying irrigation pond and dam location(s) was considered in this study. To achieve this goal, the criteria for eligibility for water harvesting areas have been completed on the basis of the conditions in the study methods. Based on the hydrological and geomorphological standards of the study area, suitable sites for harvest areas were identified and it was divided into four classes in terms of their suitability for water harvesting, namely very low, low, moderate, and high suitable for water harvesting. It can be concluded that the findings of this research can be used to assist in water resources management as an efficient planning tool to ensure sustainable development of the water in Iraq who suffers from water shortages.Validerad;2020;Nivå 2;2020-11-26 (johcin)</p

Energy Content Estimation of Municipal Solid Waste by Physical Composition in Al-Diwaniyah City, Iraq

This study was undertaken to estimate the energy potential of municipal solid waste via creating a relationship between the high heating value (HHV) and the fractions of physical composition of municipal solid waste MSW (% food, % plastic, % paper, % wood, % textile) into the two scenarios, namely wet MSW (as discarded) and dry (free moisture). The created models were determined based on the results of obtained from the analysis of the components of the Al-Diwaniyah MSW and then from previous studies which involved experimental ultimate analysis (% C, % O, % H, % N, %S) of MSW, supported by the equations and models of previous studies which were used for HHV calculation. SPSS Statistical software was used to prepare the models. For each scenario, the input datasets were 60 cases, taking into account the minimization of the data and the average of HHV that result from equations. Four models were created, two models for each status where R2 was 1.00 and 0.999 for dry and wet situation, respectively. However, the equations of verification process showed that the models which depended on the dry fractions are more accurate. The produced HHV from the dry and wet MSW components in the Al-Diwaniyah City is 8655 KJ/Kg and 6440 KJ/Kg, respectively (as discarded)

Effectiveness of Sequencing Batch Biofilm Reactor Technology to Treat Domestic Wastewater in Basrah City

The efficiency of a Sequencing Batch Biofilm Reactor (SBBR) for domestic wastewater treatment in Basrah was assessed. The experiments were carried out via a laboratory-scale SBBR cylindrical vessel used for this study, with geometric volume of 26 L, having an internal diameter of 15 cm, a height of 40 cm, and a working volume of 13 L. After a one-month start-up cycle for biofilm growth on the fibrous filler, the SBBR research test period lasted two months. The SBBR was run for three weeks to ensure that the biological treatment systems were mature and those steady-state requirements were reached, throughout the starting-up phase of operation, the removal efficiency for COD, NH3-N, TN, and TP were 95%, 89%, 85%, and 93% respectively. The impact of aeration time on the SBBR efficiency was also tested by removal of COD, ammonia, total nitrogen TN, and total phosphorous TP under different levels of dissolved oxygen DO (2.0 – 6.8) mg\L. The SBBR method proved to be an effective method for treating domestic wastewater in Basrah city. The COD, NH3-N, TN, and TP concentrations in the effluent were 42, 6.7, 9.0, and 1.0 mg/L, respectively, with the removal efficiency rates of 90.32 %, 86.24 %, 84.75 %, and 84.38 %. When comparing the SBBR effluent value to the WHO, European, Iraqi, and Chinese discharge standards, it was observed that the COD concentration (42 mg/L) met these standards. while ammonia (6.7 mg/L), TN (9.0 mg/L), and TP (1.0 mg/L) met the WHO, European, and Chinese standard only

Drivers and consequences of child marriage in a context of protracted displacement: a qualitative study among Syrian refugees in Egypt

BACKGROUND: Child marriage is a human rights violation disproportionately impacting girls in low- and middle-income countries. In the Middle East region, conflict and displacement have prompted concerns that families are increasingly resorting to child marriage to cope with economic insecurity and fears from sexual violence. This study set out to examine child marriage among Syrian refugees residing in Egypt with the aim of understanding drivers of child marriage in this context of displacement as well as how child marriage affects refugee girls’ wellbeing. METHODS: This analysis draws from 15 focus group discussions (FGD) conducted with married and unmarried girls, as well as parents of adolescent girls in three governorates in Egypt. FGDs included a participatory ranking exercise and photo-elicitation. Additionally, we conducted 29 in-depth interviews with girls and mothers, as well as 28 key informant interviews with health providers, community leaders, and humanitarian actors. The data was thematically analyzed using a combination of inductive and deductive coding. RESULTS: A prevalent phenomenon in pre-war Syria, child marriage has been sustained after the influx of Syrian refugees into Egypt by pre-existing cultural traditions and gender norms that prioritize the role of girls as wives and mothers. However, displacement into Egypt engendered different responses. For some families, displacement-specific challenges such as disruptions to girls’ education, protection concerns, and livelihood insecurity were found to exacerbate girls’ vulnerability to child marriage. For others, however, displacement into urban areas in Egypt may have contributed to the erosion of social norms that favored child marriage, leading to marriage postponement. Among girls who were married early, we identified a range of negative health and social consequences, including lack of family planning use, disruption to schooling and curtailment of girls’ mobility as well as challenges with marriage and birth registration which accentuated their vulnerability. CONCLUSION: Efforts to address child marriage among Syrian refugees must acknowledge the different ways in which displacement can influence child marriage attitudes and practices and should capitalize on positive changes that have the potential to catalyze social norm change. Moreover, targeted, focused and contextualized interventions should not only focus on preventing child marriage but also on mitigating its impacts