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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Transforming Organic Waste Into A Marketable Product: A Conjoint Analysis Of Bulk Compost Preferences And Strategies For Expanding The Compost Market In Vermont

Keeney, Daniel Colin 01 January 2014 (has links)
Organic waste management presents challenges and opportunities alike for community-based economic development. Waste-to-compost transformation can be socially and economically successful by employing ecological design principles, multi-stakeholder collaboration, and values-based supply chains (VCs). An analysis of commercial buyers' preferences for compost will inform approaches to forming effective partnerships of public, private and nonprofit stakeholders to develop a market for local waste resource products. The thesis summarizes the results of a consumer preferences survey of current and prospective bulk compost purchasers and discusses strategies for implementing new organic waste management policies that will strengthen a local market for compost, build social capital and share economic value. A conjoint analysis of bulk compost preferences in Vermont was conducted to identify the market's preference for quality-based attributes of bulk compost. The data was taken from a survey administered by mail to Vermont business professionals in various fields that use--or could potentially use--compost products in providing goods or services. In addition to price (81 percent of the relative importance buyers place on an attribute), local provenance (8 percent) and suitability for organic production (7.6 percent) were demonstrated as statistically significant determinants of the value buyers placed on compost. Willingness to pay for local provenance and suitability for organic production were measured at 15% and 14% above the baseline product price, respectively. Current and prospective compost producers can effectively market their products and retain a competitive edge in the marketplace by collaborating with other businesses. A viable market for Vermont compost could be achieved through cultivation of niche specialties, stable institutional buyers, more stringent regulation of food waste and nutrient management behavior, and a collaborative effort to construct a product narrative that emphasizes compost's role in a larger social-ecological system of nutrient management and sustainable agriculture.
2

Mapeamento do campo da gestão de resíduos orgânicos na cidade de São Paulo / Mapping the field of Organic Waste Management in São Paulo City

Cseh, Amanda 13 December 2018 (has links)
A fração orgânica representa uma parte significativa da problemática dos resíduos sólidos dispostos em aterros sanitários. Esses resíduos, quando recebem tratamento apropriado, podem ser assimilados pela natureza, gerando benefícios socioambientais para a produção de alimentos, mitigação de mudanças climáticas e recuperação de solos degradados. O objetivo desta dissertação foi entender o estágio da gestão de resíduos orgânicos na cidade de São Paulo. Elementos da teoria de campos de ação estratégica foram aplicados ao estudo de caso exploratório e qualitativo. Foram realizadas 16 entrevistas semiestruturadas com representantes de organizações da sociedade civil, funcionários de empresas de limpeza pública, gestores públicos para levantamento de dados primários e a análise documental para os dados secundários. A análise sociológica do discurso foi utilizada para a discussão dos resultados. A gestão de resíduos orgânicos está emergindo como campo. Neste caso, os atores estão delineando coletivamente suas ações estratégicas e organizando-se em dois possíveis quadros: o quadro interpretativo dominante modelo de aterros sanitários e dois quadros alternativos: um voltado para a gestão centralizada e o outro que se caracteriza pela visão de uma gestão descentralizada. Por fim, identificou-se uma tendência de tênue mudança na trajetória no campo de gestão dos resíduos orgânicos / The organic waste is a significant problem in landfills disposal of solid waste. When managed appropriately, this fraction can be assimilated by nature, generating socioenvironmental benefits for food production, mitigation of climate change and recovery of degraded soils. This study sought to understand the organic waste management stage in the city of São Paulo. Elements of the theory of strategic fields of action were applied to the exploratory and qualitative case study. Sixteen semi-structured interviews were conducted with representatives of civil society organizations, public cleaning company employees, public managers for primary data collection, and documentary analysis for secondary data. The sociological discourse analysis was used to discuss the results. Organic waste management is emerging as a field. In this case, the actors are collectively delineating their strategic actions and organizing themselves into two possible frameworks: the dominant interpretive framework - landfill model and two alternative frameworks: one focused on centralized management and the other characterized by a management vision decentralized. Finally, a trend of a slight change in the trajectory in the field of organic waste management was identified
3

Mapeamento do campo da gestão de resíduos orgânicos na cidade de São Paulo / Mapping the field of Organic Waste Management in São Paulo City

Amanda Cseh 13 December 2018 (has links)
A fração orgânica representa uma parte significativa da problemática dos resíduos sólidos dispostos em aterros sanitários. Esses resíduos, quando recebem tratamento apropriado, podem ser assimilados pela natureza, gerando benefícios socioambientais para a produção de alimentos, mitigação de mudanças climáticas e recuperação de solos degradados. O objetivo desta dissertação foi entender o estágio da gestão de resíduos orgânicos na cidade de São Paulo. Elementos da teoria de campos de ação estratégica foram aplicados ao estudo de caso exploratório e qualitativo. Foram realizadas 16 entrevistas semiestruturadas com representantes de organizações da sociedade civil, funcionários de empresas de limpeza pública, gestores públicos para levantamento de dados primários e a análise documental para os dados secundários. A análise sociológica do discurso foi utilizada para a discussão dos resultados. A gestão de resíduos orgânicos está emergindo como campo. Neste caso, os atores estão delineando coletivamente suas ações estratégicas e organizando-se em dois possíveis quadros: o quadro interpretativo dominante modelo de aterros sanitários e dois quadros alternativos: um voltado para a gestão centralizada e o outro que se caracteriza pela visão de uma gestão descentralizada. Por fim, identificou-se uma tendência de tênue mudança na trajetória no campo de gestão dos resíduos orgânicos / The organic waste is a significant problem in landfills disposal of solid waste. When managed appropriately, this fraction can be assimilated by nature, generating socioenvironmental benefits for food production, mitigation of climate change and recovery of degraded soils. This study sought to understand the organic waste management stage in the city of São Paulo. Elements of the theory of strategic fields of action were applied to the exploratory and qualitative case study. Sixteen semi-structured interviews were conducted with representatives of civil society organizations, public cleaning company employees, public managers for primary data collection, and documentary analysis for secondary data. The sociological discourse analysis was used to discuss the results. Organic waste management is emerging as a field. In this case, the actors are collectively delineating their strategic actions and organizing themselves into two possible frameworks: the dominant interpretive framework - landfill model and two alternative frameworks: one focused on centralized management and the other characterized by a management vision decentralized. Finally, a trend of a slight change in the trajectory in the field of organic waste management was identified
4

Food Waste Management in a Circular Economy Perspective : A case study of Swedish juice plant Loviseberg presseri AB / Matavfall ur ett cirkulärt ekonomiskt perspektiv : Fallstudie av den svenska juice fabrikören Loviseberg presseri AB

Salazar Ruiz Velasco, Maria Fernanda January 2019 (has links)
One third of all the food produced for human consumption is being wasted all around the world. The recovery and optimum use of this food waste is vital to support the growing population and food demand. The main objective of this research is to identify the optimum use of organic waste, using a circular economy approach, to generate recommendations that help industries in the food sector to reduce and valorize waste. A case study for food waste management alternative selection with the Swedish juice plant Loviseberg presseri AB is presented. This study furthermore proposes a detailed operation procedure of the selected options according to the results exploring the potential add value to the residue remaining from cold-pressed juice process. It was found that 49% of the total weight from raw material is wasted after the extraction process, being apple and orange the larger contributors. The research identified and recommended, for the specific case study, that the optimum use of apple pomace is used for ingredient for human consumption products, followed by animal feed and pectin production. As for the orange waste, it was identified to be used for essential oil extraction, followed by animal feed and anaerobic digestion. Furthermore, the results of the research shows, that a combination of the different waste management alternatives would also benefit the company. The research also identified potential challenges as well as benefits, which depend in the specific waste analyzed. / En tredje del av all mat som produceras slängs och bättre hushållning är avgörande för att kunna förse den växande befolkningen med livsmedel. Huvudsyftet med denna rapport är att identifiera den optimala användningen av organiskt avfall, med hjälp av en cirkulär ekonomi, generera rekommendationer som hjälper industrier inom livsmedelssektorn att minska och värdera livsmedelsavfall. En fallstudie för alternativ hantering av matavfall hos svenska juice-anläggningen Loviseberg presseri AB presenteras. Denna studie föreslår vidare en detaljerad hantering av de valda alternativen, i enlighet med resultaten, som undersöker det potentiella mervärdet för återstoden från kallpressad juice. Det visade sig att 49% av den totala vikten från råmaterial blir till avfall efter extraktionsprocessen, där äpple och apelsiner är de största bidragsgivarna. Studien identifierade att den optimala användningen av äppelmassa är som ingrediens för konsumtionsprodukter, följt av djurfoder och pektinproduktion. När det gäller avfallet från apelsiner identifierades extraktion av eterisk olja, följt av djurfoder och anaerob biogasproduktion som bästa alternativen. Vidare visar resultaten av studien att även en kombination av de olika avfallshanteringsalternativen skulle gynna företaget. Studien identifierade också potentiella utmaningar såväl som fördelar som beror på det specifika avfallet som analyserats.
5

Propuesta de instalación de una planta productora de compost en el distrito de Pátapo para satisfacer la demanda

Sales Fernandez, Ricardo Erick January 2023 (has links)
La presente investigación tiene como propósito elaborar un estudio de pre-factibilidad para la instalación de una planta productora de compost en el distrito de Pátapo, aprovechando los residuos orgánicos para satisfacer la demanda de abono orgánico, para ello se plantearon tres objetivos: evaluar la pre-factibilidad comercial, técnica y financiera. En base a ello, se obtuvo que para el año 2026 se tiene una demanda insatisfecha de 4 111 421 toneladas de abono orgánico, donde el precio de venta de los sacos de 50 kg de compost para ese mismo año sería de S/61,58. En relación al aspecto técnico, dicho distrito para el año 2026 estaría generando un total de 16 578,37 kg de residuos sólidos al día, de las cuales el 74,86% está representado por residuos orgánicos, para ello la planta requiere de un área total de 4 423,03 𝑚2 de acuerdo al Método de Guerchet y estaría ubicado en el mismo distrito, donde se estaría empleando un sistema de compostaje cerrado y la capacidad diseñada sería 31 sacos/h. Así mismo referente al aspecto financiero, se requiere una inversión total de S/ 7 097 607,70, de las cuales el 76,4% se estaría financiando y como indicador de rentabilidad presenta un VAN de S/ 4 181 709,36 mientras que en el costo beneficio sería que por cada S/1 invertido, se estaría ganando S/2,50. En síntesis, es viable la instalación la planta de acuerdo a sus tres aspectos evaluados, donde se estaría cumpliendo con el 8,15% de la demanda nacional insatisfecha para el año 2026. / The purpose of this research is to prepare a pre-feasibility study for the installation of a compost production plant in the district of Pátapo, taking advantage of organic waste to meet the demand for organic fertilizer, for this, three objectives were proposed, which are to evaluate the commercial, technical and financial pre-feasibility. Based on this, it was obtained that for the year 2026 there is an unsatisfied demand of 4 111 421 tons of organic fertilizer, where the sale price of the 50 kg bags of compost for that same year would be S / 61,58. In relation to the technical aspect, said district by 2026 would be generating a total of 16 578,37 kg of solid waste per day, of which 74,86% is represented by organic waste, for this the plant requires an area total of 4 423,03 𝑚2according to the Guerchet method and would be located in the same district, where a closed composting system would be used and the designed capacity would be 31 bags / h. Likewise, regarding the financial aspect, a total investment of S / 7 097 607,70 is required, in which 76,4% would be financed and as an indicator of profitability it presents a VAN of S / 4 181 709,36 while that the cost benefit would be S / 3,50. In summary, the installation of the plant is viable according to its three evaluated aspects, where it would be meeting 8,15% of the unsatisfied national demand by 2026.
6

Ecological food sense : connections between food waste flows and food production in Enkanini Informal Settlement, Stellenbosch

Mollatt, Michelle Claire 04 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2014 / ENGLISH ABSTRACT: In situ Informal Settlement Upgrading (ISU) was explored in this thesis, focussing on its relevance to waste service upgrading options immediately available and practically implementable for residents of Enkanini, a poorly serviced township (slum) in Stellenbosch, South Africa. Household food waste (kitchen scraps) was chosen as a key point of entry for exploring the context and viability of in situ improvement of solid waste management services in the area. This was done by investigating ways biological and social aspects of soil quality and food waste management can be incrementally improved in the settlement. Transdisciplinary methodology, Participatory Action Learning and Social Learning perspectives, combined with ecological thinking were used to explore different methods of managing food waste in Enkanini. A food waste collection pilot project was initiated in Enkanini by the Stellenbosch Municipality in 2012. The project was modified and continued in 2013, which served as the case study for this thesis. In 2013, food waste was collected by 56 households over five months. It was treated with Bokashi Effective Micro-organisms (Bokashi EM) containing yeasts, lactic acid bacteria, actinomycetes and photosynthetic bacteria. The Bokashi EM partially fermented the waste before it was used for composting or feeding to Black Soldier Fly (Hermetia illucens) larvae. Laboratory testing of food waste, compost, soils and larvae waste residue determined the safety, potential and sustainability of food waste for recycling and contribution to local urban agriculture by closing the organic waste loop, and for generating an income stream. A total of 5851kg food waste was collected, saving 6m3 landfill space. Households generated 5,2kg - 9,6kg food waste per week. Extrapolating this lower figure for all of Enkanini (about 2400 households), about 50,2 tonnes of food waste could be generated per month. If this were collected and recycled or composted, this would save 51,2m3 landfill space per month. The most commonly cited benefit of food waste collections by participants was reduction of vermin in or around their homes. Laboratory testing indicated that some samples had high levels of Escherichia coli (E. coli) bacteria. No traces of Salmonella were found in food waste, compost and soil samples, and most were within acceptable limits for heavy metals. It was cautioned that vegetables grown on soils or compost with high E. coli be washed or cooked before consumption. Following socially and ecologically sustainable management of Enkanini’s food waste requires a combination of waste management methods. Options include localised composting - burying EM treated food waste in soil; in situ container composting of waste and adding this to soil; processing of EM treated food waste by Black Soldier Fly larvae (and their subsequent use as feed for chickens or fish); and finally by anaerobic digestion for generation of biogas and effluent fertiliser in local biodigestors. The thesis showed that biological elements (such as bacteria and soil nutrients) have impacts on residents in communities and these need to be considered significant. The thesis suggests ecological elements be considered as indicators or building blocks for ISU locally, nationally and internationally. Keywords: in situ incremental upgrading, food waste management, Effective Micro-organisms, social learning, urban agriculture, closed-loop systems, organic waste management, informal settlements. / AFRIKAANSE OPSOMMING: In situ Opgraderingsprojek vir Informele Nedersetting (OIN) is in hierdie tesis ondersoek, met die fokus om die relevansie van afval diens opgradering opsies prakties te implementeer vir die inwoners van Enkanini, Stellenbosch, Suid Afrika, 'n gemeenskap met swak dienslewering. Huishoudelike kombuis voedselafval is gekies om die konteks en lewensvatbaarheid van in situ verbetering van vaste afval bestuur dienste te ondersoek. Dit is bereik deur maniere te ondersoek om die biologiese en sosiale aspekte van die kwaliteit van grond en voedselafval bestuur in die nedersetting te verbeter. Transdissiplinêre metode, Deelnemende Aksie Leer en Sosiale Leerprosesse, gekombineer met ekologiese denke, is gebruik is om verskillende metodes van die bestuur van voedselafval in Enkanini te verken. 'N Enkanini voedselafval versamelingsprojek is in 2012 deur die Stellenbosch Munisipaliteit begin. Dit is in 2013 aangepas en vir hierdie studie gebruik. Gedurende vyf maande in 2013 is voedselafval deur 56 huishoudings ingesamel. Dit is behandel met Bokashi effektiewe mikro-organismes (EM Bokashi) met gis, melksuur bakterieë, aktinomisete en fotosintetiese bakterieë. Die Bokashi EM het die afval gedeeltelik gegis voordat die afval gebruik was vir kompos of voeding aan Swart Soldaat Vlieg (Hermetia illucens) larwes. Voedselafval, kompos, grond en larwe oorskot laboratourim toetse het die veiligheid bepaal, asook die potensiaal en volhoubaarheid van die afval vir herwinning en die bydrae tot die plaaslike stedelike landbou deur middel van die organiese afval siklus, en vir inkomste generering. 5851kg voedselafval is ingesamel en 6m³ se opvullingsruimte bespaar. Die huishoudings het 5,2kg – 9,6kg voedselafval per week gegenereer. Die laer syfer in aggeneem, kan sowat 50,2 ton voedsalafval per maand in Enkanini (ongeveer 2400 huishoudings) gegenereer word. As dit ingesamel, herwin of gekomposteer was, sou 51,2 m³ opvullingsruimte per maand bespaar word. Die belangrikste voordeel van die voedselafval versamelings was die vermindering van knaag en aasdiere rondom wonings. Laboratoriumtoetse het hoë vlakke van Escherichia coli (E. coli) bakterieë in sommige monsters gevind. Geen spore van Salmonella is in die voedselafval, kompos en grondmonsters gevind nie en meeste was binne die aanvaarbare perke vir swaar metale. Die gemeenskap is gewaarsku om groente wat in die grond of kompos gekweek is voor verbruik in chloorwater te was of kook. Die sosiale en ekologies volhoubare bestuur van Enkanini se voedselafval vereis 'n kombinasie van afval bestuursmetodes. Opsies sluit gelokaliseerde kompos - begrawe EM behandelde voedsel afval in die grond; in situ houer kompos afval en die toevoeging van hierdie tot die grond; verwerking van EM behandelde voedselafval deur Swart Soldaat Vlieg larwes (en hul daaropvolgende gebruik as voer vir hoenders of vis); en uiteindelik deur mestvergisting vir die generasie van biogas en kunsmis in biovergisters. Die tesis toon dat biologiese elemente (soos bakterieë en voedingstowwe in grond)'n impak het op die gemeenskap se inwoners en as n belangrik faktor beskou moet word. Die tesis dui ekologiese elemente as n toekomstige aanwysers aan indien OIN plaaslik, nasionaal of internasionaal oorweeg word. Sleutelwoorde: in situ toenemende opgradering, kos afval bestuur, effektiewe mikro-organismes, sosiale leerproses, stedelike landbou, geslotestelsel-sisteme, organiese afval, informele nedersettings.
7

Diseño de modelo de la cadena de suministro del fertilizante orgánico para reutilizar desechos orgánicos y aumentar el consumo de fertilizantes en el Perú / Design of a model eco-friendly fertilizer supply chain to reuse organic waste and increase consumption of fertilizers in Peru

Flores Yaranga, Andrea Luz, Vasquez Perez, Renzo Alberto 22 November 2020 (has links)
Durante muchos años, el consumo global de fertilizantes ha mostrado una tendencia positiva, que también se refleja en el sector agrícola peruano. Sin embargo, en Perú el consumo de fertilizantes en kilogramos por hectárea agrícola es muy bajo en comparación con los países de América del Sur, ya que se consumen alrededor de 128 kilogramos por hectárea, cuando la recomendación de la Organización de las Naciones Unidas para la Agricultura y la Alimentación es de aproximadamente 204 kilogramos por hectárea. hectárea agrícola. Por ello, este problema fue analizado en el contexto del mercado agrícola peruano para determinar las posibles causas raíz, que ayudarían a incrementar el consumo de fertilizantes en el Perú. Se determinó que este problema es causado principalmente por el comercio centralizado de fertilizantes en el departamento de Lima y por la baja importación anual de fertilizantes orgánicos, que impactan directamente en la baja disponibilidad de fertilizantes orgánicos. Por ello, este artículo propone un modelo de cadena de suministro de fertilizantes ecológicos a través de la metodología SCOR para emplear la mejor solución posible que abarque todas las incertidumbres de la disponibilidad de fertilizantes orgánicos en el Perú. Este modelo identificará una mejora en los costos operativos y la rentabilidad para las partes interesadas en esta cadena de suministro. Como resultado final, el proyecta presenta una mejora en la sustentabilidad, la cual se incrementó en 2.8 y sostenibilidad, cuya mejora se incrementó en 3.2 con respecto a la situación actual de la cadena de suministro del floculo. / For many years, the global consumption of fertilizers has shown a positive trend, which is also reflected in the Peruvian agricultural sector. However, in Peru the consumption of fertilizers in kilograms per agricultural hectare is very low compared to the countries of South America, since around 128 kilograms per hectare is consumed, when the recommendation of the United Nations Organization to Agriculture and Food is approximately 204 kilograms per agricultural hectare. For this reason, this problem was analyzed in the context of the Peruvian agricultural market to determine the possible root causes, which would help to increase the consumption of fertilizers in Peru. It was determined that this problem is caused mainly by the centralized trade of fertilizers in the department of Lima and by the low annual import of organic fertilizers, which directly impact on the low availability of organic fertilizers. For this reason, this article proposes a supply chain model for eco-friendly fertilizer through the SCOR methodology to employ the best possible solution that encompasses all the uncertainties of the availability of organic fertilizers in Peru. This model will identify an improvement in operating costs and profitability for stakeholders in this supply chain. As a result, an economic acceptance of the project is obtained since in this case 4 financial indicators were used to determine the economic viability of the project. As a final result, the project presents an improvement in sustainability, which increased by 2.8 and sustainability, whose improvement was increased by 3.2 with respect to the current situation of the floc supply chain. / Trabajo de investigación
8

Hydrothermal processing of waste biomass: recovery of nutrients (N, P, soil amendments) and energy valorization

Scrinzi, Donato 18 July 2023 (has links)
Many environmental crises are threatening to collapse human societies, but also life on the Earth as we may know. Climate change due to anthropogenic global emissions is one of the main issues, but also soil degradation, and the management of the enormous amount of organic wastes that are harmfully released into the environment by human activities. On the one hand, direct spreading of biowastes onto the land is often limited due to eutrophication or pollution by toxic compounds. On the other hands, these biomasses may contain nutrients, such as phosphorus (listed as a critical raw material) and nitrogen, which could be recovered to sustain the high demand in expensive soil amendments and fertilizers. Thus, finding new solution to close the loop towards circular economy and sustainable processes is crucial, nowadays, to convert the global trends and restore the delicate equilibrium in the water-food-energy nexus, with soil ‘under special surveillance’. In this framework, many researchers are focusing their attention on hydrothermal carbonization (HTC) as a possible candidate, in particular to treat moist biowastes and obtain useful solid (hydrochar) and liquid (HTC liquor) products. Nutrients contained in biowastes are sensitive to HTC process parameters and initial feedstock properties, thus it is crucial to analyze their distribution and (im)mobilization among the HTC products for their reuse in soil. On the other hand, since some organic compounds are generated during the thermochemical process, which may be responsible for toxicity to plants and other organisms, analysis of their possible toxicity towards the biosphere becomes crucial before implementation at a large scale. This thesis collects our efforts to explore new processes and deepen the knowledge about the possibility to produce amendments suitable for soil application from hydrochar. The core is from a process engineering perspective, focusing on the production phase and the characterization of the products, never forgetting any possible limits or the implications on ecotoxicological issues. In the first part of the thesis, ‘How to make hydrochar a soil amendment?’ is the main question. Based on few pioneer studies about composting of hydrochar, we assessed a complete analysis of hydrochar co-compost, produced from the 25-day aerobic stabilization of digestate of organic fraction of municipal solid waste, together with a fraction of its hydrochar, and green waste. Under the umbrella of C2Land project (funded by The European Institute of Innovation & Technology -EIT), we produced this new amendment in specifically designed bioreactors, then we characterized the products from the point of view of physico-chemical properties, nutrients distribution, toxicity to plants and mammalian cells. We are confident that the crucial result of toxicity removal from hydrochar through composting will attract the interest of many stakeholders, since implementing HTC in anaerobic/aerobic plants is almost ready to be applied at a large scale. Moreover, an experimental campaign performed at the University of Leeds further explored the effect of some other post-treatments on hydrochar composition and phytotoxicity, depending on the initial feedstocks (manure, sewage digestate, water hyacinth, and grass). The second part of the thesis was dedicated to nutrients recovery, necessary when some harmful matrixes - such as the municipal sewage sludge digestate - are not allowed to be reused for agricultural purposes, due to law limitations or pollution issues. In this case, nutrients recovery (N, P) could be achieved chemically, via HTC and struvite precipitation, being struvite recognized as a good fertilizer. Firstly, we performed a techno-economic assessment of the implementation at a district level of HTC-centered sewage sludge management. The mass reduction of waste streams may have some important effects on transportation costs, while the recirculation of HTC liquor back to the anaerobic digestors can imply more biomethane production with increased revenues. A mass balance for the potential of N and P recovery through struvite precipitation in the centralized facility was also assessed. Secondly, a near-zero waste treatment process for municipal sewage sludge via HTC was designed according to the available literature and preliminarily analyzed at lab level. The fractionation of the different types of phosphorus was analyzed through the STM-P protocol before and after HTC, confirming the mineralization of organic phosphorus during the process. Citric acid was validated as a good green solvent for phosphorus extraction and high-quality struvite precipitation, even if the process was not still optimized in terms of yields. Future works may identify the best process parameters for final metal recovery from liquid byproducts in order to internally recirculate them back to water line, and to characterize the leached hydrochar as purified renewable fuel or soil amendment. Thus, the proof-of-concept chain would be confirmed and could be applied to the sustainable HTC-centered biorefineries of the future.

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