1. |
- Ddiba, Daniel Isaac Waya, 1990-, et al.
(författare)
-
A review of how decision support tools address resource recovery in sanitation systems
- 2023
-
Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 342
-
Forskningsöversikt (refereegranskat)abstract
- Globally, there is increasing interest in recovering resources from sanitation systems. However, the process of planning and implementing circular sanitation is complex and can necessitate software-based tools to support decision-making. In this paper, we review 24 decision support software tools used for sanitation planning, to generate insights into how they address resource recovery across the sanitation chain. The findings reveal that the tools can address many planning issues around resource recovery in sanitation including analysis of material flows, integrating resource recovery technologies and products in the design of sanitation systems, and assessing the sustainability implications of resource recovery. The results and recommendations presented here can guide users in the choice of different tools depending on, for example, what kind of tool features and functions the user is interested in as well as the elements of the planning process and the sanitation service chain that are in focus. However, some issues are not adequately covered and need improvements in the available tools including quantifying the demand for and value of resource recovery products, addressing retrofitting of existing sanitation infrastructure for resource recovery and assessing social impacts of resource recovery from a life cycle perspective. While there is scope to develop new tools or to modify existing ones to cover these gaps, communication efforts are needed to create awareness about existing tools, their functions and how they address resource recovery. It is also important to further integrate the available tools into infrastructure planning and programming processes by e.g. customizing to relevant planning regimes and procedures, to move them beyond research and pilots into practice, and hopefully contribute towards more circular sanitation systems.
|
|
2. |
- Ddiba, Daniel Isaac Waya, 1990-, et al.
(författare)
-
Governing the circular economy : Assessing the capacity to implement resource-oriented sanitation and waste management systems in low- and middle-income countries
- 2020
-
Ingår i: Earth System Governance. - : Elsevier BV. - 2589-8116. ; 4, s. 100063-
-
Tidskriftsartikel (refereegranskat)abstract
- Transitioning to a circular economy requires strategic investments in infrastructure, but it also requires policy coherence, coordination and collaboration among stakeholders across sectors and governance levels. In this paper, we aimed to identify the factors that facilitate or impede governance capacity to adopt circularity in the form of resource recovery from urban organic waste streams. We conducted a literature review and semi-structured interviews using the ‘Governance Capacity Framework’ in a case study of Naivasha, Kenya. Our findings emphasize the importance of leadership from the public sector in co-developing visionary strategies for circularity and using their convening power to facilitate cross-sectoral collaboration. Moreover, we identify a need for bridging theoretical circular economy concepts to initiatives in local communities of practice. The insights in this paper are relevant for advancing the understanding of challenges for governance of the circular economy especially in low-and middle-income country contexts.
|
|
3. |
- Ddiba, Daniel Isaac Waya, 1990-, et al.
(författare)
-
Sustainability assessment of increased circularity of urban organic waste streams
- 2022
-
Ingår i: Sustainable Production and Consumption. - : Elsevier BV. - 2352-5509. ; 34, s. 114-129
-
Tidskriftsartikel (refereegranskat)abstract
- The circular economy, from an urban organic waste perspective, is seen as an approach to deal with increasing waste streams, while contributing to meeting the increasing demand for water, energy, food and other resources in urban areas. However, there is need for a systematic assessment of the broader environmental and social ben-efits and trade-offs of resource recovery from organic waste streams. This paper presents a framework for assessing the societal impacts of increased circularity in terms of resource recovery from organic waste streams at city scale, building on the design of alternative scenarios for future technology systems. The framework was developed based on a literature review of current frameworks in the area, adapting and combining some of their aspects and adding required features to allow for a broad sustainability assessment. It was also informed by stakeholder interviews. The framework was applied to the case of Naivasha, Kenya to illustrate its applicability and usefulness. The outcome of the application in the Naivasha case indicate potential sustainability improve-ments from increased circularity, where resource recovery could lead to a reduction of greenhouse gas emissions, more efficient natural resource usage and job creation. It indicated also some risks of negative impacts on the health of workers in resource recovery facilities, and, in this specific case, negative impact on smallholder farmers. The framework proved applicable and useful in the case study, and hence could provide input at early stages of planning even with low availability of data. Thereby it could provide policy-relevant insights towards circular economy implementation approaches that harness the benefits while mitigating any identified potential negative impacts.
|
|
4. |
- Ddiba, Daniel Isaac Waya, 1990-, et al.
(författare)
-
The circular economy potential of urban organic waste streams in low- and middle-income countries
- 2021
-
Ingår i: Environment, Development and Sustainability. - : Springer Nature. - 1387-585X .- 1573-2975.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- There is growing recognition of the potential environmental and socio-economic benefits of applying a circular economy approach to urban organic waste management through resource recovery. Decisions around planning and implementing circular urban waste systems require estimates of the quantity of resources available in waste streams and their potential market value. However, most case-studies have so-far been conducted in high-income countries and cities in low- and middle-income countries have different challenges when developing a circular economy. The present paper explores these issues by estimating the potential for resource recovery from organic waste streams in the context of low- and middle-income countries, illustrated in Kampala, Uganda. A simplified material flow analysis approach is used to track the transformation of waste streams, namely; faecal sludge, sewage sludge and organic solid waste into the resource recovery products biogas, solid fuel, black soldier fly larvae and compost. Findings indicate that even at current rates of waste collection, the three waste streams combined could annually yield 135,000 tonnes of solid fuel or 39.6 million Nm3 of biogas or 15,000 tonnes of black soldier fly larvae or 108,000 tonnes of compost. Potential revenues from the products could range from 5.1 million USD for compost to 47 million USD for biogas, annually. This case study demonstrates how complex information describing urban waste in specific cities can be presented to facilitate decision-making and planning by stakeholders. By highlighting different resource recovery opportunities, application of this approach could provide an incentive for more sustainable urban sanitation and waste management systems.
|
|
5. |
- Ntostoglou, Eftychia, et al.
(författare)
-
Understanding the interactions between biowaste valorisation and the Sustainable Development Goals: insights from an early transition stage
- 2024
-
Ingår i: International Journal of Urban Sustainable Development. - : Taylor & Francis Group. - 1946-3138 .- 1946-3146. ; 16:1, s. 53-72
-
Tidskriftsartikel (refereegranskat)abstract
- The valorisation of urban biowaste can contribute to a circular and sustainable resource management. However, biowaste valorisation is not inherently sustainable. This study employs the Sustainable Development Goals (SDGs) to investigate the sustainability implications of biowaste valorisation. A narrative literature review provided an overview of the current scientific knowledge on interactions between biowaste valorisation and selected SDG targets. Then stakeholder interviews yielded insights into such interactions in a national context. Our findings show the potential for 19 synergies and 11 trade-offs between biowaste valorisation and 20 selected SDG targets that are addressed in detail. Although the synergies outnumber the trade-offs, different context-dependencies influence the nature and strength of the interactions. We highlight three types of context-dependencies relating to governance. This study informs the scientific community and decision-makers on planning for sustainable biowaste valorisation that addresses context-dependencies. The insights can guide countries and cities at early transition stages towards biowaste valorisation.
|
|
6. |
- Oster, Michael, et al.
(författare)
-
Bridging gaps in the agricultural phosphorus cycle from an animal husbandry perspective: The case of pigs and poultry
- 2018
-
Ingår i: Sustainability. - Basel, Switzerland : MDPI. - 2071-1050. ; 10:6
-
Tidskriftsartikel (refereegranskat)abstract
- Since phosphorus (P) is an essential element for life, its usage and application across agricultural production systems requires great attention. Monogastric species such as pigs and poultry can significantly contribute to global food security but these animals remain highly dependent on the supply of mineral inorganic P in their feeds. Pig and poultry, which represent 70% of the global meat production, are also major P excretors and thus represent important sources of environmental P inputs. Balancing the P cycle within farming systems is crucial to achieve P sustainable and resilient livestock production. Therefore, the interconnection of animal feed, livestock farming, manure, and soil/aquatic ecosystems requires multidisciplinary approaches to improve P management. With regard to a sustainable agricultural P cycle, this study addresses aspects of feeding strategies and animal physiology (e.g., phase feeding, P conditioning, liquid feeding, phytase supplementation, genetics), soil agroecosystems (e.g., P cycling, P losses, P gains), reuse and recycling (e.g., manure, slaughter waste), measures of farmers' economic performance (e.g., bio-economic models), and P governance/policy instruments (e.g., P quota, P tax). To reconcile the economic and ecological sustainability of animal husbandry, the strategic objective of future research will be to provide solutions for a sufficient supply of high-quality animal products from resource-efficient and economically competitive agro-systems which are valued by society and preserve soil and aquatic ecosystems.
|
|
7. |
- Strande, Linda, et al.
(författare)
-
Methods to reliably estimate faecal sludge quantities and qualities for the design of treatment technologies and management solutions
- 2018
-
Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 223, s. 898-907
-
Tidskriftsartikel (refereegranskat)abstract
- Sanitation access in urban areas of low-income countries is provided through unstandardized onsite technologies containing accumulated faecal sludge. The demand for infrastructure to manage faecal sludge is increasing, however, no reliable method exists to estimate total accumulated quantities and qualities (Q&Q) This proposed approach averages out complexities to estimate conditions at a centralized to semi-centralized scale required for management and treatment technology solutions, as opposed to previous approaches evaluating what happens in individual containments. Empirical data, demographic data, and questionnaires were used in Kampala, Uganda to estimate total faecal sludge accumulation in the city, resulting in 270 L/capâyear for pit latrines and 280 L/capâyear for septic tanks. Septic tank sludge was more dilute than pit latrine sludge, however, public toilet was not a distinguishing factor. Non-household sources of sludge represent a significant fraction of the total and have different characteristics than household-level sludge. Income level, water connection, black water only, solid waste, number of users, containment volume, emptying frequency, and truck size were predictors of sludge quality. Empirical relationships such as a COD:TS of 1.09 ± 0.56 could be used for more resource efficient sampling campaigns. Based on this approach, spatially available demographic, technical and environmental (SPA-DET) data and statistical relationships between parameters could be used to predict Q&Q of faecal sludge.
|
|
8. |
- Vanhuyse, Fedra, et al.
(författare)
-
The lack of social impact considerations in transitioning towards urban circular economies : a scoping review
- 2021
-
Ingår i: Sustainable cities and society. - : Elsevier BV. - 2210-6707. ; , s. 103394-103394
-
Tidskriftsartikel (refereegranskat)abstract
- Worldwide, cities are implementing circular economy (CE) strategies to reduce the resources they consume and their environmental impact. However, the evidence of the intended and unintended social consequences of the transition to “circular cities” is scattered. The lack of a coherent overview of the evidence on the subject can hinder effective decision-making in policy and practice. This study examines the extent to which the current literature addresses the social impacts that a transition to a CE produces in cities. We used a methodological approach related to systematic mapping to collate the evidence published over the past decade globally. The study finds that social impacts have rarely been considered in studies of circular cities, and where they have been discussed, the scope has been quite limited, only covering employment (mostly of informal sector workers) and governance practices. This scoping review highlights the need to further analyse and integrate social impact considerations into decision-making connected to transitions towards circular cities.
|
|