In many countries, policymakers, researchers and other stakeholders have advocated that using materials previously regarded as waste as an important step towards a more sustainable future. The issue, however, is that using waste is not easy in practice. Concerns regarding safety, cleanliness, profitability, and quality are frequently raised. My focus is on Swedish sewage sludge use in agriculture, a practice which went from six percent of the total amount sewage sludge produced to 46 percent between 2002 and 2020. The main guiding question is how actors like researchers, farmer federations, industrial organizations, wastewater treatment plant operators, and public agency representatives negotiate what sewage sludge is and how it should be used. The study contributes to the emerging literature on resourcification, a theoretical approach which understands that resources become through practice. I also draw on concepts from multiple ontology research to demonstrate how complex materials like sewage sludge become a matter of political contestation. 

The study is based on researchers’ arguments published in scientific papers over the past fifty years, Swedish stakeholders’ opinion statements to four governmental inquiries over the past twenty years, minutes from a wastewater treatment certification organization (Revaq) from 2011 to 2022, and interviews with the expert panel initiated by the 2018 governmental sewage sludge inquiry. Analytically, I focus on how sewage sludge is related to other objects and phenomena and by that enacting what the sludge should be. I argue that farmers, wastewater treatment plant operators, researchers, and recycling companies have enacted sewage sludge as a fertilizer, partially through the establishment of a certificate. In the Swedish agricultural sector, sewage sludge has now become a usable good. This enactment, however, requires constant support to fend off the challenges presented by other ways of enacting what sewage sludge is and should become. 

Beslutsfattare, forskare och andra intressenter i många länder förespråkar att göra avfall användbart som ett viktigt steg mot en mer hållbar framtid. Problemet är dock att användning av avfall inte är enkelt i praktiken. Oro kring säkerhet, renlighet, lönsamhet och kvalitet lyfts ofta fram. Mitt fokus ligger på användningen av svenskt avloppsslam inom jordbruket, en praxis som ökade från sex procent av den totala mängden avloppsslam producerad till 46 procent mellan 2002 och 2020. Den vägledande frågan är hur aktörer som forskare, lantbruksförbund, branschorganisationer, avloppsreningsverksoperatörer och representanter för offentliga myndigheter förhandlar om vad avloppsslam är och hur det bör användas. Studien bidrar till den framväxande litteraturen om resursifiering, en teoretisk ansats som utgår från att resurser blir till genom praktik. Studien bygger på forskarnas problemformuleringar publicerade i vetenskapliga artiklar under de senaste femtio åren, svenska intressenters remissvar till fyra statliga utredningar under de senaste tjugo åren, protokoll från en certifieringsorganisation för avloppsrening (Revaq) från 2011 till 2022 samt intervjuer med den expertpanel som initierades av den statliga utredningen om avloppsslam 2018. Jag visar att avloppsslam relateras till olika objekt och fenomen. Jag argumenterar för att bönder, operatörer av avloppsreningsverk, forskare och återvinningsföretag har förverkligat avloppsslam som en gödsel, delvis genom införandet av ett certifikat. Inom den svenska jordbrukssektorn har avloppsslam blivit en användbar vara. Denna förvandling kräver dock kontinuerligt stöd för att möta de utmaningar som andra sätt att förstå vad avloppsslam är och bör bli innebär.

Sewage sludge management is torn between a desire for pollution prevention and reuse of a valuable resource. Reconciling these interests in sustainable management is a challenge for researchers. This study focuses on how research on sewage sludge management practices has evolved and scrutinizes how this research is interlinked with concerns and societal issues such as contaminants, economic efficiency, and legislation. Based on published academic papers on sewage sludge management between 1971 and 2019, this study found four trends in research focused on sewage sludge management: a decreasing interest in disposal (landfilling and sea dumping), a dominant interest in land application, a growing interest in sewage sludge as product, and a stable interest in energy recovery. Research on disposal focuses on increasing sludge volumes, legislative changes, and economic challenges with an interest in waste co-treatment. Research on land application concerns nutrient use and contaminants, mainly heavy metals. Research on sewage sludge as a product focuses on the extraction of certain resources and less on use of sewage sludge specifically. Research on energy recovery of sewage sludge focuses on volume reduction rather than contaminants. Two-thirds of the papers are detailed studies aiming to improve single technologies and assessing single risks or benefits. As management of sewage sludge is multifaceted, the narrow focus resulting from detailed studies promotes some concerns while excluding others. Therefore, this study highlights potential gaps such as the combination of nutrient use and disposal and energy recovery and nutrient use.

Recycling nutrients from renewable sources, like sewage sludge, has been promoted as a step towards a circular economy by decreasing extraction and dependency on inorganic fertilizers. Implementation, however, is often controversial. In 2018, a Swedish governmental inquiry was commissioned to propose a complete ban on land application of sewage sludge to reduce soil pollution and increase phosphorus recovery. In 2020, the inquiry suggested two pathways, one to ban all land application, and one where agricultural land use should continuously be allowed. This paper is based on interviews with experts tied to the inquiry where they reference to sewage sludge, related objects, and future management. The inquiry’s inability to propose a coherent suggestion is analysed inspired by the concept of multiple ontology. Several ontological versions of sewage sludge emerge that unveil tensions between concepts of danger and cleanliness, pollution and naturalness, often captured in previous studies of waste. Some versions of sewage sludge conflict, which can explain the difficulty to establish an ontologically singular knowledge base for a transformation of sewage sludge from waste to resource. Though most of the experts agree that circular economy and nutrient recycling are good things, policymaking is caught in an ontological conundrum.

This article discerns why the substantial political efforts to increase circulation of nutrients in sewage sludge, and phosphorus in particular, have shown such meager results over the last twenty years in Sweden. We have analyzed stakeholders’ statements of opinions to four government-initiated inquiries, to decipher the chemo-social relations between stakeholders and phosphorus, and how these relations have transformed over time and made a difference in the policy process. In our analysis, we found five different relations: 1) a metabolic, 2) a purity, 3) a nutritional, 4) a marketable, and 5) a geopolitical. These relations connect actors, phosphorus and politics in different ways, and obstruct policymaking by creating tensions between political objectives, values and stakeholder positions. We observe how the extraction of phosphorus as a singular, marketable element to be sold for profit reasons on a global market, is increasingly favored in comparison to local eco-cycling of nutrients between farmers and consumers. We see this as a consequence of that the circular economy as a concept has replaced eco-cycle efforts in the Swedish policy debate. We conclude that if circular economy-initiatives are to be successfully implemented, they need to be informed by the current configuration of material flows that they wish to transform as well as the political implications of their efforts. So far, this has not been the case regarding sewage sludge in Sweden.

The European Directive 86/278/EEC implemented in 1986 was a means adopted by the European Union to improve use of the valuables in sewage sludge by applying treated sludge on agricultural soils. To prevent an accumulation of pollutants, the Directive provided suggestions limiting concentrations of toxic elements in sewage sludge and agricultural soil. The Directive was implemented diversely throughout EU member states, with current national legislations only partly reflecting the initial intentions of the EU Directive from 30 years ago. This study demonstrates how the European Directive was implemented in three countries currently at different stages of replacing the agricultural application of sewage sludge with incineration (Netherlands, Germany and Sweden). Additionally, recent changes in the legislation with regards to the re-use and final disposal of sewage sludge in the three chosen member states are analysed. The aim was to investigate how each member state has solved the conflict between improvement of nutrient recovery from sludge and limitation of pollutants in agricultural soil. Based on this review, limit values are not necessarily reflected in application rates of sewage sludge in agriculture. Following changes in current legislation, phosphorus recovery will become a priority task. The recovery of other valuables from sewage sludge is currently not regulated in the legislation of the three member states investigated.

The Sweden Democrats (SD) was the first radical right populist party (RRPP) to be elected to the Swedish Parliament in 2010, and today it is an established and important force in Swedish politics. The SD have the lowest proportion of female members of all parties in the Swedish Parliament, and also retain the view that there are biological and cognitive differences that affect men’s and women’s roles in society. There is, however, a growing tendency to emphasize the need for gender equality and even feminism in the party. Previous research (Mulinari & Neergaard 2013; Towns, Karlsson & Eyre 2014) has dismissed these attempts as rhetorical duplicity aiming at constructing immigrants as an out-group. In this paper we analyse interviews conducted with women representatives of the SD in local, regional and national assemblies. By mapping ideas about gender and equality and by identifying the ontological scales on which they exist, we paint a picture of a party with a dynamic and sometimes contradictory understanding of gender equality. Several gender equality discourses co-exist in SD ideology, but their inconsistency is caused by changes in context rather than by purposeful ambiguity.

The Sweden Democrats (SD) was the first radical right populist party (RRPP) to be elected to the Swedish Parliament in 2010, and today it is an established and important force in Swedish politics. The SD have the lowest proportion of female members of all parties in the Swedish Parliament, and also retain a traditionalist view that there are biological and cognitive differences that affect men’s and women’s roles in society. There is, however, a growing tendency to emphasize the need for equality and even feminism in the party. Previous research has dismissed this as rhetorical duplicity aiming at defining immigrants as an out-group. In this paper we analyse interviews conducted with women representative for the SD in local, regional and national assemblies. By mapping ideas about gender and equality and by identifying the ontological scales on which they occur, we paint a picture of a party with a dynamic and sometimes contradictory understanding of equality. Several equality discourses co-exist in SD ideology, but their use is the result of contextual application rather than purposeful ambiguity.