Removal of steroid estrogens from municipal wastewater in a pilot scale expanded granular sludge blanket reactor and anaerobic membrane bioreactor

Anaerobic treatment of municipal wastewater offers the prospect of a new paradigm by reducing aeration costs and minimizing sludge production. It has been successfully applied in warm climates, but does not always achieve the desired outcomes in temperate climates at the biochemical oxygen demand (BOD) values of municipal crude wastewater. Recently the concept of fortification' has been proposed to increase organic strength and has been demonstrated at the laboratory and pilot scale treating municipal wastewater at temperatures of 10-17°C. The process treats a proportion of the flow anaerobically by combining it with primary sludge from the residual flow and then polishing it to a high effluent standard aerobically. Energy consumption is reduced as is sludge production. However, no new treatment process is viable if it only addresses the problems of traditional pollutants (suspended solids - SS, BOD, nitrogen - N and phosphorus - P); it must also treat hazardous substances. This study compared three potential municipal anaerobic treatment regimes, crude wastewater in an expanded granular sludge blanket (EGSB) reactor, fortified crude wastewater in an EGSB and crude wastewater in an anaerobic membrane bioreactor. The benefits of fortification were demonstrated for the removal of SS, BOD, N and P. These three systems were further challenged with the removal of steroid estrogens at environmental concentrations from natural indigenous sources. All three systems removed these compounds to a significant degree, confirming that estrogen removal is not restricted to highly aerobic autotrophs, or aerobic heterotrophs, but is also a faculty of anaerobic bacteria

Engineering biological wastewater treatment for the removal of hazardous chemicals.

The European Union’s Environmental Quality Standards (EQS) continue to be stringent with regards to discharge of hazardous chemicals (HCs) (mainly organic micropollutants) from wastewater treatment plants (WWTPs). The strict limits are driven by the growing interest in wastewater reuse, evidence of feminisation of male aquatic species and bioaccumulation of HCs in water-based biota. WWTPs are the last barrier to these chemicals getting into the environment from homes, institutions and industries and therefore optimisation of existing WWTPs is critical. The operational conditions of the WWTPs such as solid retention time (SRT), hydraulic retention time (HRT), dissolved oxygen (DO) concentration and seasonal temperature variations have been proven to influence the removal of these HCs and also affect the microbial/bacterial diversity in WWTPs. This study therefore aimed to find the missing link in the literature, which is to seek the relationship between the microbial/bacterial diversity or abundance and HCs removal in WWTPs. A pilot-scale study was conducted to analyse the microbial and bacterial diversity using phospholipids fatty acid and 16S rRNA analysis respectively at 3, 10 and 27 d SRT (at constant 8 h HRT) and then repeated at a fixed 27 d SRT while HRT varied at 8, 16 and 24 h. The concentrations of nonylphenols and estrogens in the influent and effluent were also analysed using LC-MS/MS to determine the plant’s chemical removal efficiency. The results showed that raising SRT (from 3 to 27 d) and HRT (from 8 to 24 h) increased bacterial diversity by 2.7 times and increased the removal of EE2 by 11%. The pilot-scale also revealed 32 novel positive correlations between bacterial genera abundance and HCs removal. The abundances of Hyphomicrobium, Mesorhizobium, Planctomyces, and Rhizomicrobium positively correlated with the removals of estrogens (E1, E2 and E3) and with nonylphenols (NP₂ EC, NP ₅EO) at r- values >0.7. The experiment was repeated by surveying the bacterial diversity in 12 full-scale activated sludge plants (ASPs) operating at varying DO levels, SRTs (4.9 to 22.3 d), HRTs (6.2 to 26.6 h) and temperature (10.6 to 20.3 ˚C). The concentrations of 26 micropollutants (analgesics, antibiotics, anti-depressants, beta-blockers, estrogens, flame retardants etc.) were also analysed in the influent and effluent. The results showed that bacterial diversity in the full- scale reactor differed from that of the pilot-scale plant. Euclidean distance matrix shows that temperature (p<0.005) was the most influential parameter in chemical removal and bacterial diversity. SRT and HRT were also important in bacterial diversity and HC removal but not in every ASP. Removal of HC followed a pseudo first order kinetics with metformin and ibuprofen achieving >98% removals. DO concentration did not show any effect due to lack of variation across the WWTPs. Once again, some novel correlations between bacterial genera abundance and chemical removal were found. The abundances of Candidatus Accumulibacter (a phosphate accumulating bacteria capable of denitrification) and Nitrosomonas (nitrite-oxidising bacteria) correlate positively with the removal of trixylenyl phosphate (flame retardant) at R>0.7. Anaeromyxobacter dehalogenans abundance also correlates positively with the removal of erythromycin. This work has shown that process parameters do influence both bacterial diversity and hazardous chemical removal, and there are correlations between bacteria taxa abundance and HCs removal. This knowledge will be vital in the discussion on improving existing activated sludge plants achieve better chemical removal and it will also be the foundation for future research into correlations of bacterial taxa abundance with chemical removal in the ASP reactor.Engineering and Physical Sciences (EPSRC)PhD in Water, including Desig

Improving the Establishment and Yield of Soybean through Planting Depth and Land Preparation Methods in Northern Ghana

Two field experiments, organized in randomized complete block design, were conducted in 2005 and 2006 farming seasons at Nyankpala in the Northern Region of Ghana to investigate the effects of planting depth (1, 2, 4, 6 and 8 cm) and land preparation methods (flat field, mounding and ridging) on crop establishment (percentage number of established plants) and grain yield of soybean (Glycine max cv. Anidaso). In the 2005 farming season results indicated that crop establishment increased from planting depth of 1 cm (97.75%), reached a peak at 4 cm (98.82%) and declined through 6–8 cm (94.15%) under flat field condition. Nodule formation was high between planting depth of 2 and 4 cm. Generally, the number of pods and grain yield decreased with increasing plant depth. The grain yield values for 1, 2, 4, 6 and 8 cm depths were 4.25, 4.22, 3.87, 3.26 and 3.12 t/ha, respectively. In the 2006 farming season, at 4 cm planting depth ridging gave the highest crop establishment of 97.77%. The highest number of pods was recorded for mound (197 per plant) followed by ridge (189 per plant) and flat (143 per plant). This pod formation characteristic reflected in the grain yield of 6.14 t/ha, 5.95 t/ha and 4.07 t/ha for mound, ridge and flat, respectively. The study revealed that for good crop establishment and optimum grain yield of soybean in northern Ghana planting could be done on mounds or ridges at planting depth between 1 and 4 cm. Ridging may be preferred because it can easily be prepared mechanically using a tractor to save time and labour

Influence of solids and hydraulic retention times on microbial diversity and removal of estrogens and nonylphenols in a pilot-scale activated sludge plant.

The removal of EDCs in activated sludge processes can be enhanced by increasing solid and hydraulic retention times (SRT and HRT); it has been suggested that the improvement in removal is due to changes in microbial community structure (MCS). Though the influence of SRT and HRT on chemical removal and MCS has been studied in isolation, their synergistic impact on MCS and the removal of estrogens and nonylphenols in activated sludge remains unknown. Hence, we investigated how both parameters influence MCS in activated sludge processes and their ulterior effect on EDC removal. In our study, an activated sludge pilot-plant was fed with domestic sewage fortified with 100 and 1000 ng/L nonylphenols or 2 and 15 ng/L estrogens and operated at 3, 10 and 27 d SRT (constant HRT) and at 8, 16 and 24 h HRT (constant SRT). The MCS was assessed by phospholipid fatty acids (PLFA) analysis, and the archaeal and bacterial diversities were determined by 16S rRNA analysis. From the PLFA, the microbial abundance ranked as follows: Gram-negative > fungi > Gram-positive > actinomycetes whilst 16S rRNA analysis revealed Proteobacteria > Bacteroidetes > Others. Both PLFA and 16S rRNA analysis detected changes in MCS as SRT and HRT were increased. An SRT increment from 3 to 10 d resulted in higher estrone (E1) removal from 19 to 93% and nonylphenol-4-exthoxylate (NP4EO) from 44 to 73%. These findings demonstrate that EDC-removal in activated sludge plants can be optimised where longer SRT (>10 d) and HRT (>8 h) are suitable. We have also demonstrated that PLFA can be used for routine monitoring of changes in MCS in activated sludge plants

An investigation of the evidence of benefits from climate compatible development

Climate change is likely to have profound effects on developing countries both through the climate impacts experienced, but also through the policies, programmes and projects adopted to address climate change. Climate change mitigation (actions taken to reduce the extent of climate change), adaptation (actions taken to ameliorate the impacts), and on-going development are all critical to reduce current and future losses associated with climate change, and to harness gains. In the context of limited resources to invest in climate change, policies, programmes, or projects that deliver ‘triple wins’ (i.e. generating climate adaptation, mitigation and development benefits) – also known as climate compatible development – are increasingly discussed by bilateral and multilateral donors. Yet there remains an absence of empirical evidence of the benefits and costs of triple win policies. The purpose of this paper is therefore to assess evidence of ‘triple wins’ on the ground, and the feasibility of triple wins that do not generate negative impacts. We describe the theoretical linkages that exist between adaptation, mitigation and development, as well as the trade-offs and synergies that might exist between them. Using four developing country studies, we make a simple assessment of the extent of climate compatible development policy in practice through the lens of ‘no-regrets’, ‘low regrets’ and ‘with regrets’ decision making. The lack of evidence of either policy or practice of triple wins significantly limits the capacity of donors to identify, monitor or evaluate ‘triple wins at this point in time. We recommend a more strategic assessment of the distributional and financial implications of 'triple wins' policies

Adaptation to climate change or non-climatic stressors in semi-arid regions? Evidence of gender differentiation in three agrarian districts of Ghana

This work was carried out under the Adaptation at Scale in Semi-Arid Regions project(ASSAR). ASSAR is one of five reserarch programs funded under the Collaborative Adaptation Reseasrch Initiative in African and Asisa (CARIAA), with financial support from the UK Government's Department for International Development (DfID) and the International Development Research Centre (IDRC),Canada (107640-001).The views expressed in this work are those of the authors and do not necessarily represent those of DfID and IDRC or its Board of Governors. Special thanks go to the Climate Change, Agriculture and Food Security (CCAFS) projects secretariat in Ghana for the support in linking our research with the CCAFS district platform chairpersons. We also would like to acknowledge the support of Stephen Omari in fieldwork data collection as well as chairpersons of CCAFS district platforms.We are also grateful to the anonymous reviewers for their comments.With the increasing impacts of climate change in Africa, a relationship between rainfall and yields in semi-arid Ghana has been observed. Drawing insights from three agrarian societies in the semi-arid region of Ghana using qualitative research methods, the study reports how people currently deal with climate variability as insight on how they will deal with climate change in the future. The findings indicate wide gender inequality in decision making processes and land access resulting from patriarchal local customs and institutions that shape adaptation responses of different vulnerable social groups to climatic or non-climatic stressors. Different adaptation practices of groups indicate that both climatic and non-climatic stressors shape the kind of responses that groups adopt. From the current adaptation practices, efforts to improve adaptation to future climate change at local levels must give attention to the nexus of both climatic and non-climatic stressors, gender, differential vulnerabilities and other subjectivities that produce a particular adaptation practice in a given place

Assessment of Knowledge and Consumption Patterns of Soybean, Moringa Oleifera, Aloe Vera and Other Agro-Resources: The Case of the Elderly and Pregnant/Nursing Women in Lome, Togo

Purpose: To assess how soybean products and other agro-resources are known and consumed by some vulnerable populations in Lome (Togo). Methods: A cross sectional study was conducted from March to April 2015 among people aged 50 years and over attending two Pension Fund departments and pregnant and nursing women attending Bè Hospital in Lome. Data were collected using a pre-tested face-to-face questionnaire. Participants were surveyed about their knowledge and consumption habits of soybean, Moringa oleifera, Aloe vera products and other agro-resources. Results: A total of 847 respondents were included in the study with 426 pregnant/nursing women and 421 people aged 50 years and over. The majority of respondents were married (39.5%) and 45.3% of the elderly people were widowed. At least nine over ten respondents (96%) knew soybean products and 76.8% of them reported a lifetime consumption of soybean products. The available and most consumed agro-resources included tofu (82.7%), moringa leaves (87.2%) and soy flour (29.7%). The least consumed products were soymilk, soy yogurt and moringa juice. Respondents also reported using moringa tea and soap, as well as Aloe vera juice and toothpaste. Conclusion: Soybean products and other agricultural resources are well known and consumed by people living in Lome. Data on actual food intake is useful to public health professionals and food safety risk assessors. It is important to inform the public at large of the recognized benefits of some foods that will provide solutions to their health problems

Political Economy of Climate Compatible Development: Artisanal Fisheries and Climate Change in Ghana

This chapter presents results of research that explores the socio-political forces and challenges by understanding the political economy of climate compatible development (CCD) in relation to artisanal fisheries in Ghana. The analysis provides insight into the complex political economy in Ghana's artisanal fisheries, a sector that has received little attention with regard to climate change linkages. This could help other projects and wider initiatives on climate change locate their work within a political economy context and target efforts in politically smart ways. The chapter outlines the context for the artisanal fisheries sector and challenges to its sustainability and relations with climate change. It then analyses the politics of climate change policy formulation, including its relationship with the fisheries sector. Ghana is an excellent example of the additional challenges climate change and variability pose to development. It has achieved middle-income country status yet this significant economic progress, as in all other countries, has been accompanied by rising greenhouse gas (GHG) emissions

Using Transformative Scenario Planning to think critically about the future of agriculture and food security in the Upper West Region of Ghana an overview

This work was carried out under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA), with financial support from the UK Government’s Department for International Development (DfID) and the International Development Research Centre (IDRC), Canada.In West Africa, ASSAR works in the semi-arid and dry sub-humid parts of Ghana and Mali — areas that are increasingly exposed to climatic extremes of droughts, floods and heavy rainfall. These changing conditions impact different people in different ways. For all living here, figuring out how to adapt to these uncertain circumstances is a challenging task that requires input from many different groups