Decision Support for Redesigning Wastewater Treatment Technologies

This paper offers a methodology for structuring the design space for innovative process engineering technology development. The methodology is exemplified in the evaluation of a wide variety of treatment technologies for source-separated domestic wastewater within the scope of the Reinvent the Toilet Challenge. It offers a methodology for narrowing down the decision-making field based on a strict interpretation of treatment objectives for undiluted urine and dry feces and macroenvironmental factors (STEEPLED analysis) which influence decision criteria. Such an evaluation identifies promising paths for technology development such as focusing on space-saving processes or the need for more innovation in low-cost, energy-efficient urine treatment methods. Critical macroenvironmental factors, such as housing density, transportation infrastructure, and climate conditions were found to affect technology decisions regarding reactor volume, weight of outputs, energy consumption, atmospheric emissions, investment cost, and net revenue. The analysis also identified a number of qualitative factors that should be carefully weighed when pursuing technology development; such as availability of O&M resources, health and safety goals, and other ethical issues. Use of this methodology allows for coevolution of innovative technology within context constraints; however, for full-scale technology choices in the field, only very mature technologies can be evaluated

Pathways from research to sustainable development: insights from ten research projects in sustainability and resilience

Drawing on collective experience from ten collaborative research projects focused on the Global South, we identify three major challenges that impede the translation of research on sustainability and resilience into better-informed choices by individuals and policy-makers that in turn can support transformation to a sustainable future. The three challenges comprise: (i) converting knowledge produced during research projects into successful knowledge application; (ii) scaling up knowledge in time when research projects are short-term and potential impacts are long-term; and (iii) scaling up knowledge across space, from local research sites to larger-scale or even global impact. Some potential pathways for funding agencies to overcome these challenges include providing targeted prolonged funding for dissemination and outreach, and facilitating collaboration and coordination across different sites, research teams, and partner organizations. By systematically documenting these challenges, we hope to pave the way for further innovations in the research cycle

Aerosolized Delivery of Antifungal Agents

Pulmonary infections caused by Aspergillus species are associated with significant morbidity and mortality in immunocompromised patients. Although the treatment of pulmonary fungal infections requires the use of systemic agents, aerosolized delivery is an attractive option in prevention because the drug can concentrate locally at the site of infection with minimal systemic exposure. Current clinical evidence for the use of aerosolized delivery in preventing fungal infections is limited to amphotericin B products, although itraconazole, voriconazole, and caspofungin are under investigation. Based on conflicting results from clinical trials that evaluated various amphotericin B formulations, the routine use of aerosolized delivery cannot be recommended. Further research with well-designed clinical trials is necessary to elucidate the therapeutic role and risks associated with aerosolized delivery of antifungal agents. This article provides an overview of aerosolized delivery systems, the intrapulmonary pharmacokinetic properties of aerosolized antifungal agents, and key findings from clinical studies

Assessing sustainable approaches to sanitation planning and implementation in West Africa

The challenge of achieving global sanitation targets is that it requires application of both technology that is appropriate and a supporting organizational structure. The interactions between the two begin during the planning/decision-making process and continue throughout the system lifetime. During the last decade, strategic planning frameworks have emerged in the water and sanitation sector that reflect a shift from traditional, top-down planning to a more participatory, bottom-up approach. Despite this shift and in light of the continuing challenge of achieving widespread sanitation in the world, it is necessary to question if a knowledge gap exists between the global sanitation frameworks and local stakeholder priorities. This licentiate thesis presents the first phase of a research project whose objective is to study the global models and compare them with existing local planning and decision-making conditions. It focuses on establishing the global context with regard to strategic planning tools and perspectives on sustainable sanitation. In general, there is close agreement on methodology and processes recommended by international planning frameworks; however the use of the term “sustainable sanitation” is highly variable. In general, the findings of this thesis show that improving sanitation conditions requires tools based on participation, social marketing, and process approaches for planning, capacity development, and feedback. Continuation of this research will investigate the local context regarding current planning practices and perspectives on sustainable sanitation in order to assess potential differences between the global and local context and make recommendations for improving adaptation of planning strategies for bringing sanitation to scale.QC 2010111

Estimating environmental and societal impacts from scaling up urine concentration technologies

There is a growing trend for nutrient recovery from wastewater as part of the transition to a circular economy. Most nutrients in household wastewater originate from urine and one way to facilitate reuse of these nutrients is to concentrate the urine into fertiliser products. Urine concentration technologies are still in the development phase and not implemented at scale. The aim of this study was to provide guidance to technology developers and policymakers by assessing the environmental and societal impacts of urine concentration technologies. In particular, it includes practical aspects such as worker safety, space availability and local fertiliser needs that have not been included in previous studies. Future scenarios on implementing three different urine concentration technologies (alkaline dehydration, nitrification-distillation, ion-exchange with struvite precipitation) in a planned residential area in Malmö, Sweden, were developed. The technologies were evaluated using multi-criteria assessment (MCA), with environment, technical, economic and health sustainability criteria derived from the Sustainable Development Goals (SDGs). It was found that all urine concentration technologies performed well against many of the sustainability criteria examined and can contribute to achieving SDGs, especially regarding nitrogen recovery. Specific areas for further development were identified for each technology. An impact assessment on scaling up demonstrated that nitrogen emissions to surface water were significantly reduced when more than 60% of urine in Malmö city was subjected to urine concentration. Nitrogen and phosphorus recovered from recycling only 15–30% of urine in Malmö could supply 50% of Malmö municipality's fertiliser demand

Acceptance of human excreta derived fertilizers in Swedish grocery stores

Safe recycling of nutrients found in human excreta back to agriculture is an important component of a circular economy that can protect waterways and stabilize food prices. Although many technological advances for the recovery of these nutrients exist, large-scale implementation is lacking. A commonly cited barrier is a lack of acceptance of fertilizers from human excreta and for food products grown with such fertilizers. The food retail sector, as an intermediary between producers and consumers, is an important actor with power to influence opinions and purchasing practices. In this study, we surveyed 127 food retailers (stores) and reviewed publicly available retailer sustainability policies to assess acceptance of the use of recycled fertilizers. We gauged acceptance of three products relevant for the Swedish market – struvite, phosphorus from ash, and dehydrated urine. Most respondents felt that all three recovery techniques were unlikely to be harmful either to themselves or to the environment. It was more acceptable to use products further away from human consumption. In general, struvite and phosphorus from ash were perceived more positively. Acceptance of wastewater-derived fertilizers was largely dependent on perceived risks, especially the fate of pharmaceutical residues. While retailers in Sweden are not negative to reuse, they seem unlikely to provide strong support for nutrient recirculation from human excreta unless it becomes a greater concern for the public

Structured Approach for Comparison of Treatment Options for Nutrient-Recovery From Fecal Sludge

The aim of this study is to present a structured approach for comparing possible nutrient-recovery fecal sludge (FS) treatment systems in order to support transparent decision-making. The approach uses a multi-dimensional sustainability assessment of treatment technologies for nutrient recovery from FS, using a typical case of Kampala City, Uganda. A synthesized list of 22 treatment technologies was prepared from literature. This list included wastewater treatment technologies, which could be adapted to treat fecal sludge, and established fecal sludge treatment technologies that are available or potentially applicable in Kampala. Based on the local situation, the list was reduced to eight possible options, which were carried forward into a multi-dimensional sustainability assessment that incorporated input of stakeholders. The technologies included in the final assessment were optimization of the existing system, lactic acid fermentation (LAF), composting, vermicomposting, Black-Soldier Fly (BSF) composting, ammonia treatment, alkaline stabilization and solar drying. Optimization of the existing system performed well against the set criteria and is a recommended short-term solution. This will require e.g., adding narrower screens to remove more trash from the incoming sludge and respecting storage times prior to selling the sludge. To maximize the agricultural value of the recovered product, while respecting the need for safe reuse, a combination of technologies becomes relevant; the use of a combination of BSF, and subsequent ammonia or alkaline treatment of the remaining organic fraction would allow for maximized safe nutrient recovery and can be the aim for long-term sanitation planning in Kampala. The results of this process provide supporting information for a discussion of trade-offs between stakeholder groups as part of a decision-making process within a larger planning context.Funding details: VetenskapsrÃ¥det, VR; Funding details: 2016-06297; Funding text 1: We are also grateful for the input from local stakeholders in Kampala, internal advice from colleagues and the efforts of students Solveig Johannesdottir, Erick Odom, Emma Lindberg, Anna Rost, Elina Persson and Therese H?gerup. Funding. The authors are grateful for the support of the Swedish Research Council (Vetenskapsr?det) under Grant number: 2016-06297.</p

Decision Support for Redesigning Wastewater Treatment Technologies

This paper offers a methodology for structuring the design space for innovative process engineering technology development. The methodology is exemplified in the evaluation of a wide variety of treatment technologies for source-separated domestic wastewater within the scope of the Reinvent the Toilet Challenge. It offers a methodology for narrowing down the decision-making field based on a strict interpretation of treatment objectives for undiluted urine and dry feces and macroenvironmental factors (STEEPLED analysis) which influence decision criteria. Such an evaluation identifies promising paths for technology development such as focusing on space-saving processes or the need for more innovation in low-cost, energy-efficient urine treatment methods. Critical macroenvironmental factors, such as housing density, transportation infrastructure, and climate conditions were found to affect technology decisions regarding reactor volume, weight of outputs, energy consumption, atmospheric emissions, investment cost, and net revenue. The analysis also identified a number of qualitative factors that should be carefully weighed when pursuing technology development; such as availability of O&M resources, health and safety goals, and other ethical issues. Use of this methodology allows for coevolution of innovative technology within context constraints; however, for full-scale technology choices in the field, only very mature technologies can be evaluated