Optimal recovery of resources from wastewater treatment: aspects of the developing world

Whilst there is significant improvement in access to sanitation globally, access to proper sanitation is still a great challenge in the developing world, especially the Sub Sahara Africa where 25% of the population still practiced open deification by 2012. The current sanitation systems have loop-holes and can barely help the situation. Wastewater is rich in a number of resources, which include water, energy and nutrients. These when rightly explored through recovery, present an opportunity to subsidise sanitation costs hence making it more affordable and consequently accessible for all. A paradigm shift from the ordinary centralised and onsite systems to a cluster decentralised systems which encourage resource recovery is pertinent to achieve more cost effective and manageable wastewater treatment system. This work sought to explore interventions for resource recovery that are appropriate for application in the developing world. In Chapter 1, a review of literature was done to understand the current situation in Africa, after which, a wastewater management plan that could contribute to improvement for small agricultural communities was suggested. The plan encourages zero waste generation through decentralisation and recovery of water, energy and by-products such as nutrients and organics relevant to the local community. The subsequent chapters therefore details studies in which resources from wastewater could be recovered as new water, energy and nutrients/fertilizers or simply re-used to achieve better treatment. The work considers not only domestic wastewater but also integrates wastes from other sources to bring about better wastewater treatment performance as well as increase resource recovery benefits. Chapter 2 of this work explores, the re-use of polyaluminium drinking water treatment sludge (PA-WTS) as a flocculant aid to improve the effluent quality of wastewater during primary sedimentation. The results obtained showed a tremendous decrease in total suspended solids (TSS), chemical oxygen demand (COD), total ammonium nitrogen (TAN), and total phosphates (TP) in the supernatant after 30 min of settlement. The optimal PA-WTS dosage of 37.5 mL/L significantly (P<0.05) increased the TSS, TP and COD removal efficiencies by 15, 22 and 30%, respectively. It can be concluded PA-WTS therefore positively complimented the sedimentation process in the primary treatment of wastewater to achieve better effluent quality. Among the many resources in wastewater and other wastes is the energy which can be recovered through biogas production. Chapter 3 presents a study where two organic wastes, cow dung and brewery sludge were co-digested with primary sludge in different proportions. The aim was to enhance biogas production from municipal sewage sludge. Brewery waste was found to increase the biogas production rate by a factor of ≥3. This was significantly (p<0.001) higher than that observed (336 ± 18 mL/L.d) in the control treatment containing only STP sludge. Co-digestion with brewery-waste and cow-dung improved biodegradability of municipal sewage sludge and is recommended. Apart from the increased energy recovery, digestion of other wastes with sewage sludge would also lead to cleaner cities as waste is better managed and would ultimately cut down cost of both sewage and solid waste management. Chapter 4 explores the re-use of water for agricultural purposes with a two treatment systems; a high rate activated sludge (HRAS) system and alternating charcoal filters (ACF). Two systems were in parallel with the ACF line after the HRAS. The HRAS effectively removed up to 65% of total suspended solids (TSS) and 59% of chemical oxygen demand (COD), while ACF1 removed up to 70% TSS and 58% COD. The combined treatment system of HRAS and ACF effectively decreased TSS and COD on average by 89% and 83% respectively. Total ammonium nitrogen (TAN) and total phosphates (TP) were largely retained in the effluent with removal percentages of on average 19.5% and 27.5% respectively, encouraging reuse for plant growth. The charcoal can upon saturation be dried and used as fuel. This provides a cheap way for developing countries to counter the challenge of climate change especially in regard to water scarcity. Another possible way of recovering nutrients and energy from wastewater treatment is by converting the sludge to biochar. In Chapter 5 biochar formed from high rate activated sludge (HRAS) was characterised with respect to its use as a soild improver and energy. HRAS was first anaerobically digested under mesophilic conditions at a sludge retention time of 20 days. The results showed that HRAS digested well producing on average 0.5 ± 0.15 CH4 L -1L -1d for an average OLR of 1.85 ± 0.63 g COD -1L -1d. The produced biochar showed optimal properties as a soil improver when produced at a temperature of 400°C with values of 18.11 wt%, 21.32 wt%, 60.58 % and 0.41 for volatile matter, fixed carbon, ash content and H/C ratio, respectively. With regard to energy, the biochar had a lower caloric value than the dried HRAS digestate. Based on these findings, it can be concluded that anaerobic digestion of HRAS and its subsequent biochar formation at HHT of 400°C presents a sustainable management option for sludge in tropic settings like in Uganda. Based on the results presented in the chapters of this work, future research needs are proposed in chapter 6. Among them, the need for cheaper and user friendly pyrolysis techniques that can make biochar formation sustainable in the developing world. A number of local technologies for charcoal making are already in existence and could be adopted, with optimisation aimed at increased efficiency in biochar production. With regard to the HRAS +ACF system, further studies could be dedicated to optimising the system in order to achieve complete removal of faecal coliform. Also, the used charcoal from that system could easily turn into a waste nuisance it not well managed. Yet, charcoal behaves similarly to biochar, moreover, this one also had organics adsorbed on the surface, which may increase its potential to act as a soil improver when crushed and applied to soils. Further research therefore, could consider establishing the impact of applying the crushed charcoal to soil as some form of biochar

The need to develop a successful competition regime in Uganda: an analysis of the factors hindering the operationalisation and implementation of the East African Community Competition Act

Uganda is in the process of enacting a competition law. Like most developing countries, it faces a unique adoption process, local circumstances and concerns that makes the competition law and enforcement practices distinguishable from other jurisdictions. This research will analyse the need for development of a successful competition regime in Uganda by highlighting the factors that should inform the law and policy. The study will analyse the adequacy of the current competition bill 2004 in comparison with the competition laws of Kenya, Tanzania and South Africa and propose that Uganda needs to develop a competition regime that is suited to its local development needs. The East African Community (EAC) aimed at enhancing trade liberalisation and development, among other sectors adopted the East African Competition Policy in 2004 and subsequently the East African Legislative Assembly enacted the East African Competition Act in 2006. However to date an East African Community Competition Authority has not been established and the law is not yet operational. The study will further appraise the challenges to the operationalisation and implementation of the East African Community Competition Act and suggest that apart from the fact that Uganda has not enacted a competition law as required by the East African community Protocol, there are other significant challenges hindering the operationalisation and implementation of the East African Community Competition Act

Wake With Me

This thesis outlines my research, writing, and performance process, leading up to and reflecting on the final product of my MFA Solo Thesis project. The project is entitled Wake With Me, and its performance is a shamanistic portrayal of a folklore story from my native place of origin; Kampala, Uganda. It is an exploration of the metaphorical loss of cultural identity through the literal loss of a family member, and the journey through story telling as a method to reclaim or preserve what was lost. Throughout the piece, the performer plays the role of narrator, using voice, body and mind to explore five distinct characters. These characters are all representative of significant aspects in the narrator’s life, and they act as stepping stones to a new realization and appreciation of cultural identity. A version of the original story of Nsangi And The Ogre, a copy of the final script, and my reflection on this process will be included in this document

Male involvement in utilization of emergency obstetric care and averting of deaths for maternal near misses in Rakai district in Central Uganda

Although studies have assessed male involvement in birth preparedness and complication readiness, little is known about their involvement after the onset of maternal near miss complications. This information is important in developing appropriate strategies for male involvement in accessing emergency obstetric care (EmOC) in order to reduce Uganda’s high maternal mortality ratio. The study examined the roles played by men after the onset of maternal near miss complications in Uganda. A qualitative study using narratives of 40 purposively selected maternal near misses and in-depth interviews of 10 randomly selected men was conducted. Results showed that men were involved in postpartum uptake of long term contraceptive methods, management of obstetric complications, decision making, social support, transport arrangements and provision of financial support to access EmOC. Therefore, men should be sensitized on the recommended haemorrhage medication during home births, the need for supervised deliveries and prompt referral of their wives to health facilities

Enhancement of biogas potential of primary sludge by co-digestion with cow manure and brewery sludge

Anaerobic digestion (AD) has long been used to treat different types of organic wastes especially in the developed world. However, organic wastes are still more often considered as a waste instead of a resource in the developing world, which contributes to environmental pollution arising from their disposal. This study has been conducted at Bugolobi Sewage Treatment Plant (BSTP), where two organic wastes, cow manure and brewery sludge were co-digested with primary sludge in different proportions. This study was done in lab-scale reactors at mesophilic temperature and sludge retention time of 20 d. The main objective was to evaluate the biodegradability of primary sludge generated at BSTP, Kampala, Uganda and enhance its ability of biogas production. When the brewery sludge was added to primary STP sludge at all proportions, the biogas production rate increased by a factor of 3. This was significantly (p<0.001) higher than observed gas yield (337 +/- 18 mL/(L.d)) in the control treatment containing (only STP sludge). Co-digesting STP sludge with cow manure did not show different results compared to the control treatment. In conclusion, Bugolobi STP sludge is poorly anaerobically degradable with low biogas production but co-digestion with brewery sludge enhanced the biogas production rate, while co-digestion with cow manure was not beneficial

Prevalence of maternal near miss and community‐based risk factors in Central Uganda

ObjectiveTo examine the prevalence of maternal near‐miss (MNM) and its associated risk factors in a community setting in Central Uganda.MethodsA cross‐sectional research design employing multi‐stage sampling collected data from women aged 15–49 years in Rakai, Uganda, who had been pregnant in the 3 years preceding the survey, conducted between August 10 and December 31, 2013. Additionally, in‐depth interviews were conducted. WHO‐based disease and management criteria were used to identify MNM. Binary logistic regression was used to predict MNM risk factors. Content analysis was performed for qualitative data.ResultsSurvey data were collected from 1557 women and 40 in‐depth interviews were conducted. The MNM prevalence was 287.7 per 1000 pregnancies; the majority of MNMs resulted from hemorrhage. Unwanted pregnancies, a history of MNM, primipara, pregnancy danger signs, Banyakore ethnicity, and a partner who had completed primary education only were associated with increased odds of MNM (all P < 0.05).ConclusionsMNM morbidity is a significant burden in Central Uganda. The present study demonstrated higher MNM rates compared with studies employing organ‐failure MNM‐diagnostic criteria. These findings illustrate the need to look beyond mortality statistics when assessing maternal health outcomes. Concerted efforts to increase supervised deliveries, access to emergency obstetric care, and access to contraceptives are warranted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135484/1/ijgo214.pd

Contraceptive Uptake Among Married Women in Uganda: Does Empowerment Matter?

Although contraceptive prevalence increased from 24% to 30% between 2006 and 2011, this uptake is still below global level of 62% and low levels of women empowerment could be a factor. Data was extracted from 2011 UDHS to examine associations between women’s empowerment and contraceptive uptake. We developed four empowerment indices symbolising economic and social empowerment, established associations between them and contraceptive use. Most women (83%) were from the rural areas and 61% were married for 10+ years. Most (59%) scored low on power over earnings and domestic violence indices. All indices independently were positively associated with contraceptive use, but only the reproductive health rights index was significant before (OR 2.13, 95% CI; 1.52-2.98) and after adjusting for background characteristics (AOR 1.72, 95% CI; 1.07-2.73). Empowered women were more likely to use contraceptives. More efforts in sensitisation of women about their sexual and reproductive health rights as well as ensuring more control over their earnings.

Effect of polyaluminium chloride water treatment sludge on effluent quality of domestic wastewater treatment

Water resources degeneration is accelerated by the discharge of untreated wastewater and its byproducts, hence, reuse of these wastes is a major contributor to sustaining fresh water for the coming decades. In this study, the reuse of polyaluminium water treatment sludge (PA-WTS) as a flocculant aid to improve the effluent quality of wastewater during primary sedimentation is evaluated and presented. PA-WTS was collected from Gabba water treatment plant (Gabba WTP) Uganda, after the coagulation-flocculation process that makes use of aluminium chlorohydrate (ACH). The average aluminium residue concentration in PA-WTS was 3.4 mg/L. During this study, batch laboratory experiments were conducted in a jar-test apparatus in which different doses of PA-WTS were added. The results obtained showed a decrease in total suspended solids (TSS), chemical oxygen demand (COD), total ammonium nitrogen (TAN), and total phosphates (TP) in the supernatant after 30 min of settlement. The optimal PA-WTS dosage of 37.5 mL/L significantly (P&lt;0.05) increased the TSS, TP and COD removal efficiencies by 15, 22 and 30%, respectively. It can be concluded that the PA-WTS positively complimented the sedimentation process in the primary treatment of wastewater to achieve better effluent quality.Key words: Aluminium chlorohydrate, poly aluminium sludge, reuse, wastewater, water treatment sludge

A two-stage decentralised system combining high rate activated sludge (HRAS) with alternating charcoal filters (ACF) for treating small community sewage to reusable standards for agriculture

Water scarcity increasingly drives wastewater recovery. Campaigns towards re-use of wastewater are not very common in Africa among other factors, due to a lack of efficient and cost-effective technology to treat wastewater to re-usable standards. In this study, two treatment systems, a high rate activated sludge (HRAS) system and alternating charcoal filters (ACF) are combined and used to treat wastewater to standards fit for reuse in agriculture. The charcoal can upon saturation be dried and used as fuel. Two different ACF lines were used in parallel after the HRAS: ACF1 with a residence time of 2.5 h and ACF2 with residence time of 5 h. Results show no significant difference (α = 0.05) in the performance of the two filter lines, hence ACF1 with a higher flow rate was considered as optimal. The HRAS effectively removed up to 65% of total suspended solids (TSS) and 59% of chemical oxygen demand (COD), while ACF1 removed up to 70% TSS and 58% COD. The combined treatment system of HRAS and ACF1 effectively decreased TSS and COD on average by 89 and 83%, respectively. Total ammonium nitrogen (TAN) and total phosphates (TP) were largely retained in the effluent with average removal percentages of 19.5 and 27.5%, respectively, encouraging reuse for plant growth.Key words: A-stage, sustainable wastewater treatment, resource recovery, developing countries, water reuse, nutrient management, agriculture

Clinico-pathological pattern and early post-operative complications of gastro-duodenal perforations at Mulago Hospital Kampala- a prospective cohort study

Background: Gastro-Duodenal Perforations are one of the commonest causes of mortality and morbidity in conditions that require emergency surgery. The main objective of this study was to determine the clinico-pathological pattern and evaluate factors for early post operative complications of Gastro-duodenal perforations in Mulago. Methods: This was a prospective cohort study of patients with gastro-duodenal perforations managed by simple repair between September 2014 and April 2015 in Mulago was studied. Primary/ secondary outcomes were mortality and complications respectively. Data was managed using stata-12 and multivariate analysis using log-binomial regression model. Results: A total of 65 patients were operated for Gastro-duodenal perforations in the study period. 86.2% were male (M: F 6.2:1). Median age was 35 years (range 16- 80 years). 93.9% had gastric perforations. Clinical diagnosis was predicted in 89.3%. H. pyloriwas present in 7.9%. Mortality was 18.5% and complications developed in 58.5%. Age above 35 and presence of   co morbidity predicted mortality (CI 1.22- 21.12, p= 0.009) (CI 1.26- 8.82, p= 0.024) and early post-operative complications (CI 1.03- 2.44, p= 0.031) (CI 1.23- 2.44, p= 0.011) respectively. Conclusion: Gastroduodenal perforations remain a common surgical emergency in Mulago hospital affecting mainly young men below 35 years. Majority are gastric perforations. Mortality and early post-operative complications are high, and increase with age and presence of co morbidity. Keywords: gastro-duodenal perforations, perforated peptic ulcer disease, gastric perforation