Anaerobic co-digestion of organic fraction of municipal solid waste (OFMSW), with thickened waste activated sludge (TWAS) and primary sludge (PS) has the potential to enhance (biodegradation) of solid waste, increase longevity of existing landfills and lead to more sustainable development by improving waste to energy production. This study reports on mesophilic batch anaerobic biological methane potential (BMP) assays carried out with different concentrations and combinations (ratios) of OFMSW, TWAS (microwave (MW) pre-treated and untreated) and PS to assess digester stability and potential improved specific biodegradability and potential increased specific biogas production by digestion of OFMSW with PS and TWAS in various tri-substrate mixtures. Results indicated improvements in specific biogas production with concomitant improvements in COD and volatile solid (VS) removal for co-digestion of OMSW, TWAS and PS vs. controls. In terms of improvements in biogas production and digester stability the OFMSW:TWAS:PS:50:25:25 ratio with or without TWAS MW treatment was deemed best for further continuous digester studies. At a 15d HRT which is the regulatory policy in the province of Ontario for municipal mesophilic anaerobic TWAS:PS treatment, co-digestion of OFMSW:TWAS:PS, and OFMSW:TWASMW:PS resulted in a 1.38 and 1.46 fold relative improvement in biogas production and concomitant waste stabilization when compared to TWAS:PS and TWASMW:PS digestion at the same HRT and volumetric VS loading rate respectively. Treatment of OFMSW with PS and TWAS provides beneficial effects that could be exploited at MWWTP that are being operated at loading rates less than design capacity.

Anaerobic co-digestion of organic fraction of municipal solid waste (OFMSW), with thickened waste activated sludge (TWAS) and primary sludge (PS) has the potential to enhance (biodegradation) of solid waste, increase longevity of existing landfills and lead to more sustainable development by improving waste to energy production. This study reports on mesophilic batch anaerobic biological methane potential (BMP) assays carried out with different concentrations and combinations (ratios) of OFMSW, TWAS (microwave (MW) pre-treated and untreated) and PS to assess digester stability and potential improved specific biodegradability and potential increased specific biogas production by digestion of OFMSW with PS and TWAS in various tri-substrate mixtures. Results indicated improvements in specific biogas production with concomitant improvements in COD and volatile solid (VS) removal for co-digestion of OMSW, TWAS and PS vs. controls. In terms of improvements in biogas production and digester stability the OFMSW:TWAS:PS:50:25:25 ratio with or without TWAS MW treatment was deemed best for further continuous digester studies. At a 15d HRT which is the regulatory policy in the province of Ontario for municipal mesophilic anaerobic TWAS:PS treatment, co-digestion of OFMSW:TWAS:PS, and OFMSW:TWASMW:PS resulted in a 1.38 and 1.46 fold relative improvement in biogas production and concomitant waste stabilization when compared to TWAS:PS and TWASMW:PS digestion at the same HRT and volumetric VS loading rate respectively. Treatment of OFMSW with PS and TWAS provides beneficial effects that could be exploited at MWWTP that are being operated at loading rates less than design capacity.

Anaerobic co-digestion of organic fraction of municipal solid waste (OFMSW), with thickened waste activated sludge (TWAS) and primary sludge (PS) has the potential to enhance (biodegradation) of solid waste, increase longevity of existing landfills and lead to more sustainable development by improving waste to energy production. This study reports on mesophilic batch anaerobic biological methane potential (BMP) assays carried out with different concentrations and combinations (ratios) of OFMSW, TWAS (microwave (MW) pre-treated and untreated) and PS to assess digester stability and potential improved specific biodegradability and potential increased specific biogas production by digestion of OFMSW with PS and TWAS in various tri-substrate mixtures. Results indicated improvements in specific biogas production with concomitant improvements in COD and volatile solid (VS) removal for co-digestion of OMSW, TWAS and PS vs. controls. In terms of improvements in biogas production and digester stability the OFMSW:TWAS:PS:50:25:25 ratio with or without TWAS MW treatment was deemed best for further continuous digester studies. At a 15d HRT which is the regulatory policy in the province of Ontario for municipal mesophilic anaerobic TWAS:PS treatment, co-digestion of OFMSW:TWAS:PS, and OFMSW:TWASMW:PS resulted in a 1.38 and 1.46 fold relative improvement in biogas production and concomitant waste stabilization when compared to TWAS:PS and TWASMW:PS digestion at the same HRT and volumetric VS loading rate respectively. Treatment of OFMSW with PS and TWAS provides beneficial effects that could be exploited at MWWTP that are being operated at loading rates less than design capacity.

Production of biogas through anaerobic digestion (AD) from the organic fraction of minucipal solid waste (OFMSW) was compared to incineration of the waste. At the moment, almost all of the OFMSW in Singapore is incinerated. Three different scales of biogas plants were compared to incineration: one large-scale biogas plant that can treat half of all OFMSW in Singapore; one medium- scale biogas plant about 15 times smaller than the large one; and one small-scale biogas plant that can treat waste from e.g. a shopping centre or food centre. Two alternatives for utilization of the biogas were also compared, generation of electricity and the use of the biogas in heavy vehicles. The combination of the different scales and the different utilization gives the six different scenarios. By using life cycle assessment (LCA) the different scenarios were compared in terms of global warming potential (GWP), acidification, eutrophication, energy use and land use. The results show that biogas production creates less environmental impact than incineration. The use of the gas as a vehicle fuel creates a bigger decrease of GWP, acidification and eutrophication than when using the gas for electricity generation. The prevention of leakage of biogas during production and upgrading is crucial for the environmental impact on GWP. A leakage of only a few percent of the produced gas will lead to a loss of all the gain in saved GHG-emissions.

Today's society is facing major challenges. In order to reduce the climate impact fossil fuels should be replaced with fuels that do not contribute to the greenhouse effect. The growing population generates organic waste originating from industry and households so called organic fraction of municipal solid waste (OFMSW). Through anaerobic digestion, waste can be utilized to produce energy-rich methane gas. In this way, waste can be a resource instead of a burden on society. The purpose of this project is to investigate the methane yield of source-sorted organic fraction of municipal solid waste (SS-OFMSW) pretreated with screw crush technology and methane yield at the co-digestion of food waste and biosludge from paper mills. SS-OFMSW which is either pre-treated in a screw crusher or a Food Waste Mill and a mixture of SS-OFMSW and biosludge from paper mills digested in a semi - continuous wet process under mesophilic conditions with a retention time of 20 days. Screw crush technique gave a slurry with a methane yield of about 440-490 mL / g VS, which was slightly higher than the yield of 300-350 mL / g VS from the slurry pretreated with Food Waste Mill. The methane concentration was slightly higher for slurry pretreated with Food Waste Mill, 74% in average compared with 68% for slurry pretreated with screw crush. Biosludge from paper mills is an organic waste that can be digested in order to produce biogas. The sludge is poor in nutrients and methane yield at individual anaerobic digestion of paper mill sludge is relatively low. In this study, biosludge was co-digested with SS-OFMSW. The mixture with the proportions 1:1 by g VS gave a methane yield of about 420-480 mL / g VS which is higher than the constituent substrates digested separately. Co-digestion gave a methane concentration at 80% which is also higher than at the individual anaerobic digestion of substrates.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-12-22T12:31:35Z No. of bitstreams: 1 Suelen Pavi_.pdf: 1636176 bytes, checksum: 0dd7b68d6b59964f41170ff034254b8d (MD5) / Made available in DSpace on 2016-12-22T12:31:35Z (GMT). No. of bitstreams: 1 Suelen Pavi_.pdf: 1636176 bytes, checksum: 0dd7b68d6b59964f41170ff034254b8d (MD5) Previous issue date: 2016-08-19 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / UNISINOS - Universidade do Vale do Rio dos Sinos / A digestão anaeróbia (DA) de resíduos é uma opção ambientalmente adequada para o tratamento de resíduos orgânicos e produção de biogás. Contudo, a eficiência do processo é influenciada por diversos fatores, incluindo a composição do substrato. Resíduos de hortifrutigranjeiros (RHF) apresentam propriedades físico-químicas adequadas para sua utilização como fonte energética. Porém, o alto teor de açúcares simples contido nas frutas e vegetais tende a acidificar o meio, inibindo a atividade dos microrganismos metanogênicos. A co-digestão com outros resíduos é uma alternativa para melhorar a estabilidade do processo. A fração orgânica dos resíduos sólidos urbanos (FORSU) também possui grande potencial energético que pode ser recuperado, e quando em co-digestão com RHF, a produção de biogás pode ser aumentada. Nesse contexto, o presente estudo buscou avaliar a produção de biogás a partir da co-digestão da FORSU com RHF, visando estabelecer uma proporção ótima onde a produção de biogás é máxima, sem danos à estabilidade do processo. O estudo foi realizado em quatro fases, em regime de batelada a 35 °C, empregando lodo anaeróbio como inóculo na relação S/I de 1/1 em termos de sólidos totais voláteis (STV). A massa de STV adicionada nos reatores foi a mesma em todas as condições. Foram testados a FORSU (Fase I) e os RHF (Fase IV) como mono-substrato e a co-digestão desses resíduos nas relações FORSU/RHF de 1/1 (Fase II) e de 1/3 (Fase III) em termos de STV. Os parâmetros monitorados foram pH, teor de sólidos totais e voláteis, carbono orgânico total, alcalinidade, ácidos graxos voláteis, ácidos orgânicos voláteis e volume de biogás. O biogás foi caracterizado quanto a teores de metano. Os resíduos aplicados na co-digestão e o biossólido final foram caracterizados quanto ao pH, teores de sólidos totais e voláteis, carbono orgânico total, alcalinidade, ácidos graxos voláteis, ácidos orgânicos voláteis, nitrogênio total e amoniacal e fósforo total. O processo de DA manteve-se estável em todas as condições de alimentação. Os resultados revelaram que a produção de biogás foi maior nas bateladas onde a FORSU e os RHF foram aplicados em co-digestão, em relação às bateladas que utilizaram FORSU e RHF como mono-substrato. A relação FORSU/RHF de 1/3 produziu o maior volume de biogás e obteve o maior rendimento de metano em função dos STV de resíduos aplicados, sendo 493,46 NL/kgSTV e 393,64 NL/kgSTV, respectivamente. / Anaerobic digestion (AD) of waste is an environmentally sound option for the treatment of organic waste and produce biogas. However, the process efficiency is influenced by several factors, including the composition of the substrate. Fruit and vegetable waste (FVW) have suitable physicochemical properties for use as an energy source. However, the high content of simple sugars contained in fruits and vegetables tend to acidify, inhibiting the activity of methanogens. The co-digestion of wastes is an alternative to improve process stability. The organic fraction of municipal solid waste (OFMSW) also has great energy potential that can be recovered, and when co-digestion with FVW, biogas production can be increased. In this context, this study aimed to evaluate the production of biogas from the co-digestion of OFMSW with FVW, to establish a great proportion where biogas production is maximum, without damage to the process stability. The study was conducted in four phases, batch system at 35 ° C, using anaerobic sludge as inoculum in the ratio S/I 1/1 in terms of the total volatile solids (VS). The VS mass added in the reactors was the same in all conditions. Were tested OFMSW (Phase I) and FVW (Phase IV) as mono- substrates and co-digestion of these wastes in relationships OFMSW/FVW 1/1 (Phase II) and 1/3 (Phase III) in terms of VS. The monitored parameters were pH, total and volatile solids, total organic carbon, alkalinity, volatile fatty acids, volatile organic acids and volume of biogas. Biogas was characterized as methane levels. Waste applied in co-digestion and the final biosolids were analyzed for pH, total and volatile solids content, total organic carbon, alkalinity, volatile fatty acids, volatile fatty acids, and total ammonia nitrogen and total phosphorus. The AD process remained stable in all power conditions. The results show that biogas production was higher in batches where OFMSW and FVW were applied by co-digestion in relation to batches that used OFMSW and FVW as mono-substrate. The relationship OFMSW/FVW of 1/3 produced the highest volume of biogas and obtained the higher yield of methane due to the VS applied to waste, being 493,46 NL/kgVS and 393,64 NL/kgVS respectively.

The UK buries about 100 million tonnes of waste a year, of which 25% is municipal solid waste (refuse). The environmental impacts from gas and leachate releases are known and direct risks to health from landfill are reported. Europe has agreed to a Landfill Directive which has set targets for the stepwise reduction in biodegradable municipal waste going to landfill. The anaerobic digestion of municipal solid waste in controlled bioreactors is an area that could play an important role in overall evolution towards sustainability by recovering biogas and organic matter. Separated hydrolysis and subsequent anaerobic codigestion was demonstrated from the literature review to have the best potential for biodegradable municipal waste diverted from landfill. The rate of hydrolysis of solids wastes remains an outstanding problem. In this research, firstly the codigestion of industrial effluent (coffee wastewater), food wastes and garden wastes were investigated for their impact on hydrolysis and digestion. The results show that there were no treatability problems for coffee wastes up to 37.5% of volume feed per day at the HRT of 9 days. The results supported the view that dilute biodegradable streams such as coffee waste may improve digestion by promoting mixing. Fruit and vegetable wastes were highly biodegradable and can have a major improvement in biogas production of the whole codigestion process, whereas garden waste was not as successful as a cosubstrate, probably because of the predominant celluloses and lignocelluloses with a low biodegradability. The literature review also revealed that washing or elutriation can remove organic matter from municipal waste. This is an important hydrolytic process in which a solubilised acidic organic matter is obtained. The codigestion of refuse hydrolysate with sewage sludge was therefore studied. A control digester treating sewage sludge only was compared with an experimental reactor fed mixed refuse hydrolysate with sewage sludge. It was possible to add the solubilised hydrolysate to existing anaerobic digesters designed at a standard sludge solids loading rate without causing overloading. (Continues...).

Nesta tese foi estudada a influência da recirculação do percolado, ajustando as melhores taxas e freqüências, para degradação da fração orgânica dos resíduos sólidos urbanos, em sistema de batelada de uma e duas fases (híbrido). Foram utilizados reatores de 3,45 litros preenchidos com resíduo sólido urbano padrão (FORSUp), percolado como inóculo e um filtro anaeróbio como reator metanogênico. Foram testadas as taxas de recirculação do inóculo de 1%, 2,5%, 5%, 10%, 20%, 30% e 50% e seu monitoramento feito por análises físico-químicas e microbiológicas. O reator que apresentou melhores valores de produção de metano e redução de DQO foi aquele com taxa de recirculação de 20% do percolado metanogênico. Na segunda etapa foram operados três digestores de 50L, alimentados com a FORSUp com as melhores taxas de recirculação determinadas na primeira etapa desse trabalho e a obtida no trabalho de Salgado (2003). Um reator simulou o reator acidogênico de um sistema de duas fases, no qual 20% de seu inóculo foi injetado em um filtro anaeróbio (com tempo de detenção hidráulico de 24 horas). Um outro sistema com taxa de 10% de recirculação de percolado foi operado como reator de uma fase. Outro reator, inoculado com a mesma quantidade de FORSUp e percolado, porém, não se realizou qualquer recirculação do seu inóculo (controle), servindo para comparar os digestores de uma e duas fases. O sistema de duas fases, comparado aos demais reatores, confirmou que a taxa de recirculação de 20%, obteve maior eficiência na partida, com elevada produção de metano e maior percentual de degradação de sólidos. Os exames microscópicos realizados em amostras de percolado desses reatores revelaram predominância de organismos de morfologia com características de Methanococcus e Methanosarcina. Concluiu-se que a taxa de recirculação de percolado influi significativamente nos reatores degradando a matéria orgânica. O estudo cinético confirmou que o processo de digestão obedece a cinética das reações em série, com elevados valores de k´1 / This thesis studied the influence of the leachate recirculation, adjusting to the best rates and frequencies, for degradation of the organic fraction of the urban solid wastes, in one and two-phases (hybrid) system. Bioreactors of 3.45 L were used and filled out with OFMSW pattern, leachate as seed and an anaerobic filter as methanogenic reactor. The performance of the reactors was analyzed varying recirculation rates (1, 2.5, 5, 10, 20, 30 and 50 % in volume of seed). Leachate samples from these reactors were examined through microscopical examinations and physical-chemical analyses to evaluate its performance. The reactor with 20% recirculation rate, got larger efficiency in the departure, methane production and percentage of solid degradation, compared to the others reactors. In the second stage, three 50L digesters were operated and fed with standard OFMSW with the best recirculation rates of the first stage and the best rate obtained in Salgado (2003). A bioreactor simulated the acidogenic reactor of a two-phase system, in which 20% of its seed was injected in anaerobic filter (with hydraulic detention time of 24 hours). Another system, with 10% of recirculation rate of leachate was operated in a one-phase reactor. Once more bioreactor, inoculated like others, however, without any recirculation were studied to compare with one and two-phase reactor. The two-phase system confirmed that the 20% recirculation rate, compared to the others reactors, obtained better efficiency with high methane production and solid degradation. The microscopical examinations in the leachate samples from this reactor presented predominance of organisms with characteristical morphology from Methanococcus and Methanosarcina. It was concluded that the leachate recirculation has significant influence in the degradation of organic matter bioreactors. The kinetic study confirmed that the anaerobic process for OFMSW proceed the in series kinetics, with high constants values of first order

Nesta tese foi estudada a influência da recirculação do percolado, ajustando as melhores taxas e freqüências, para degradação da fração orgânica dos resíduos sólidos urbanos, em sistema de batelada de uma e duas fases (híbrido). Foram utilizados reatores de 3,45 litros preenchidos com resíduo sólido urbano padrão (FORSUp), percolado como inóculo e um filtro anaeróbio como reator metanogênico. Foram testadas as taxas de recirculação do inóculo de 1%, 2,5%, 5%, 10%, 20%, 30% e 50% e seu monitoramento feito por análises físico-químicas e microbiológicas. O reator que apresentou melhores valores de produção de metano e redução de DQO foi aquele com taxa de recirculação de 20% do percolado metanogênico. Na segunda etapa foram operados três digestores de 50L, alimentados com a FORSUp com as melhores taxas de recirculação determinadas na primeira etapa desse trabalho e a obtida no trabalho de Salgado (2003). Um reator simulou o reator acidogênico de um sistema de duas fases, no qual 20% de seu inóculo foi injetado em um filtro anaeróbio (com tempo de detenção hidráulico de 24 horas). Um outro sistema com taxa de 10% de recirculação de percolado foi operado como reator de uma fase. Outro reator, inoculado com a mesma quantidade de FORSUp e percolado, porém, não se realizou qualquer recirculação do seu inóculo (controle), servindo para comparar os digestores de uma e duas fases. O sistema de duas fases, comparado aos demais reatores, confirmou que a taxa de recirculação de 20%, obteve maior eficiência na partida, com elevada produção de metano e maior percentual de degradação de sólidos. Os exames microscópicos realizados em amostras de percolado desses reatores revelaram predominância de organismos de morfologia com características de Methanococcus e Methanosarcina. Concluiu-se que a taxa de recirculação de percolado influi significativamente nos reatores degradando a matéria orgânica. O estudo cinético confirmou que o processo de digestão obedece a cinética das reações em série, com elevados valores de k´1 / This thesis studied the influence of the leachate recirculation, adjusting to the best rates and frequencies, for degradation of the organic fraction of the urban solid wastes, in one and two-phases (hybrid) system. Bioreactors of 3.45 L were used and filled out with OFMSW pattern, leachate as seed and an anaerobic filter as methanogenic reactor. The performance of the reactors was analyzed varying recirculation rates (1, 2.5, 5, 10, 20, 30 and 50 % in volume of seed). Leachate samples from these reactors were examined through microscopical examinations and physical-chemical analyses to evaluate its performance. The reactor with 20% recirculation rate, got larger efficiency in the departure, methane production and percentage of solid degradation, compared to the others reactors. In the second stage, three 50L digesters were operated and fed with standard OFMSW with the best recirculation rates of the first stage and the best rate obtained in Salgado (2003). A bioreactor simulated the acidogenic reactor of a two-phase system, in which 20% of its seed was injected in anaerobic filter (with hydraulic detention time of 24 hours). Another system, with 10% of recirculation rate of leachate was operated in a one-phase reactor. Once more bioreactor, inoculated like others, however, without any recirculation were studied to compare with one and two-phase reactor. The two-phase system confirmed that the 20% recirculation rate, compared to the others reactors, obtained better efficiency with high methane production and solid degradation. The microscopical examinations in the leachate samples from this reactor presented predominance of organisms with characteristical morphology from Methanococcus and Methanosarcina. It was concluded that the leachate recirculation has significant influence in the degradation of organic matter bioreactors. The kinetic study confirmed that the anaerobic process for OFMSW proceed the in series kinetics, with high constants values of first order

Tesis por compendio / [ES] La estrategia de la Unión Europea para la gestión de residuos se articula a través de una serie de directivas que toman como punto de partida la Directiva 2008/98/CE. En ella, se establece un marco jurídico para el tratamiento de los residuos diseñado para preservar el medio ambiente, poniendo el foco en la importancia del empleo de las mejores técnicas disponibles para la gestión, recuperación y reciclado de residuos, reduciendo así el uso de los recursos naturales. Ello ha derivado en diferentes normativas que obligan a las economías a ser más sostenibles, priorizando la minimización de residuos y, cuando no sea posible, favoreciendo su reutilización y reciclado. En España, todo ello ha sido traspuesto al ordenamiento jurídico a través de la reciente Ley 7 /2022, de 8 de abril, de residuos y suelos contaminados para una economía circular, en la que el papel protagonista recae en los municipios. La ciudad de Castelló de la Plana es una ciudad mediterránea de tamaño medio que dispone de un sistema completo de gestión de residuos sólidos urbanos y que, como todo sistema, presenta oportunidades de mejora. El objetivo fundamental de esta Tesis Doctoral es, por tanto, la mejora del sistema de gestión de residuos actual partiendo de un análisis detallado de sus principales dimensiones. Concretamente, se ha analizado la evolución histórica de las principales fracciones de residuos de la ciudad observando cómo los factores externos pueden afectar a su tendencia; se ha estudiado la composición de los biorresiduos recogidos selectivamente para ayudar al dimensionamiento de los servicios de recogida y de nuevas instalaciones de valorización provinciales; se ha propuesto la mejor tecnología de motorización disponible para la renovación de la flota de vehículos recolectores y se ha desarrollado una metodología para priorizar los planes de acción incluidos en el Plan Local de Residuos de la ciudad, a través de un análisis de sus principales indicadores. Estas propuestas de mejora están encaminadas al cumplimiento de los Objetivos de Desarrollo Sostenible fijados para el año 2030 y atienden, por tanto, a demandas de sostenibilidad y circularidad. En cuanto a la forma de presentación de este trabajo, debe reseñarse que ha sido elaborado mediante el compendio de publicaciones en las que se han evaluado las cuatro dimensiones del sistema citadas anteriormente. Para ello, se han analizado investigaciones anteriores y, utilizando los datos propios del municipio, se han realizado análisis estadísticos y de decisión multicriterio para obtener resultados que facilitan los procesos de toma de decisiones estratégicas, tácticas y operativas que mejorarán la gestión de los residuos sólidos urbanos. De estos análisis, se han extraído importantes conclusiones que permitirán manejar mejor futuras situaciones extraordinarias (como la reciente crisis sanitaria), realizar acciones encaminadas a la mejora en la separación en origen, mejorar las flotas de vehículos de recogida de residuos y optimizar los recursos municipales mediante la priorización de planes de acción. Estos resultados pueden suponer una aportación muy útil para los responsables municipales en gestión de residuos ya que, mediante el uso de los métodos aquí definidos, se proporcionan aportaciones teóricas y prácticas para la toma de decisiones, así como para el desarrollo de futuros trabajos de investigación. / [CA] L'estratègia de la Unió Europea per a la gestió de residus s'articula a través d'una sèrie de directives que prenen com a punt de partida la Directiva 2008/98/CE. En ella, s'estableix un marc jurídic per al tractament dels residus dissenyat per a preservar el medi ambient, posant el focus en la importància de l'ús de les millors tècniques disponibles per a la gestió, recuperació i reciclatge de residus, reduint així l'ús dels recursos naturals. Això ha derivat en diferents normatives que obliguen les economies a ser més sostenibles, prioritzant la minimització de residus i, quan no siga possible, afavorint la seua reutilització i reciclatge. A Espanya, tot això ha sigut transposat a l'ordenament jurídic a través de la recent Llei 7 /2022, de 8 d'abril, de residus i sòls contaminats per a una economia circular, en la qual el paper protagonista recau en els municipis. La ciutat de Castelló de la Plana és una ciutat mediterrània de grandària mitjana que disposa d'un sistema complet de gestió de residus sòlids urbans i que, com tot sistema, presenta oportunitats de millora. L'objectiu fonamental d'aquesta Tesi Doctoral és, per tant, la millora del sistema de gestió de residus actual partint d'una anàlisi detallada de les seues principals dimensions. Concretament, s'ha analitzat l'evolució històrica de les principals fraccions de residus de la ciutat observant com els factors externs poden afectar la seua tendència; s'ha estudiat la composició dels bioresidus recollits selectivament per a ajudar al dimensionament dels serveis de recollida i de noves instal·lacions de valorització provincials; s'ha proposat la millor tecnologia de motorització disponible per a la renovació de la flota de vehicles recol·lectors i s'ha desenvolupat una metodologia per a prioritzar els plans d'acció inclosos en el Pla Local de Residus de la ciutat, a través d'una anàlisi dels seus principals indicadors. Aquestes propostes de millora estan encaminades al compliment dels Objectius de Desenvolupament Sostenible fixats per a l'any 2030 i atenen, per tant, a demandes de sostenibilitat i circularitat. Quant a la forma de presentació d'aquest treball, ha de ressenyar-se que ha sigut elaborat mitjançant el compendi de publicacions en les quals s'han avaluat les quatre dimensions del sistema citades anteriorment. Per a això, s'han analitzat investigacions anteriors i, utilitzant les dades pròpies del municipi, s'han realitzat anàlisis estadístiques i de decisió multicriteri per a obtindre resultats que faciliten els processos de presa de decisions estratègiques, tàctiques i operatives que milloraran la gestió dels residus sòlids urbans. D'aquestes anàlisis, s'han extret importants conclusions que permetran manejar millor futures situacions extraordinàries (com la recent crisi sanitària), realitzar accions encaminades a la millora en la separació en origen, millorar les flotes de vehicles de recollida de residus i optimitzar els recursos municipals mitjançant la priorització de plans d'acció. Aquests resultats poden suposar una aportació molt útil per als responsables municipals en gestió de residus ja que, mitjançant l'ús dels mètodes ací definits, es proporcionen aportacions teòriques i pràctiques per a la presa de decisions, així com per al desenvolupament de futurs treballs de recerca. / [EN] The European Union's strategy for waste management is articulated through a series of directives that take Directive 2008/98/EC as a starting point. It establishes a legal framework for waste treatment designed to preserve the environment, focusing on the importance of using the best available techniques for waste management, recovery and recycling, thus reducing the use of natural resources. This has led to different regulations that oblige economies to be more sustainable, prioritizing waste minimization and, when this is not possible, favouring its reuse and recycling. In Spain, all this has been transposed into the legal system through the recent Law 7 /2022, of April 8, on waste and contaminated soils for a circular economy, in which the leading role falls to the municipalities. The city of Castelló de la Plana is a medium-sized Mediterranean city that has a complete system of solid urban waste management and that, like any system, presents opportunities for improvement. The main objective of this Doctoral Thesis is, therefore, the improvement of the current waste management system based on a detailed analysis of its main dimensions. Specifically, the historical evolution of the main waste fractions of the city has been analysed, observing how external factors can affect their trend; the composition of bio-waste collected selectively has been studied to help the sizing of collection services and new provincial recovery facilities; the best available motorization technology has been proposed for the renewal of the fleet of collection vehicles and a methodology has been developed to prioritize the action plans included in the Local Waste Plan of the city, through an analysis of its main indicators. These improvement proposals are aimed at meeting the Sustainable Development Goals set for the year 2030 and therefore address sustainability and circularity demands. With regard to the presentation of this work, it should be noted that it has been prepared by means of a compendium of publications in which the four dimensions of the system mentioned above have been evaluated. For this purpose, previous research has been analysed and, using the municipality's own data, statistical and multi-criteria decision analyses have been carried out to obtain results that facilitate the strategic, tactical and operational decision-making processes that will improve the management of urban solid waste. From these analyses, important conclusions have been drawn that will make it possible to better manage future extraordinary situations (such as the recent health crisis), carry out actions aimed at improving separation at source, improve waste collection vehicle fleets and optimize municipal resources by prioritizing action plans. These results can be a very useful contribution for municipal waste management managers since, by using the methods defined here, theoretical and practical contributions are provided for decision making, as well as for the development of future research work. / Moreno Solaz, H. (2023). Análisis y mejora del sistema integral de gestión de resíduos sólidos urbanos en la ciudad de Castellón de la Plana respondiendo a demandas de sostenibilidad y circularidad [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/199548 / Compendio