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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.
161

POLITICHE AMBIENTALI E INNOVAZIONE: IL CASO DELL'EMISSION TRADING EUROPEO / Environmental Policy and Innovation: the European Emission Trading Scheme

PONTOGLIO, SERENA 27 March 2008 (has links)
Questo lavoro esamina la relazione tra politiche ambientali ed eco-innovazione, discutendo i contributi teorici sull'argomento e i risultati delle analisi di valutazione ex-post degli effetti di politiche ambientali in contesti diversi. Si applica l'analisi degli effetti indotti d'innovazione ambientale al caso dell'emission trading europeo, il sistema di scambio dei permessi d'emissione d'anidride carbonica introdotto in Europa (Eu ets) con la direttiva 2007/83 nel 2005. Si esamina la configurazione dell'euts, il suo scostamento da un sistema ideale di permessi in grado di fornire il massimo incentivo all'innovazione, la performance del primo biennio di applicazione, confrontando emissioni allocate e verificate. Si analizza la risposta dell'industria cartaria italiana all'emission trading, attraverso lo sviluppo di un caso di studio che utilizza i risultati di un questionario sottoposto agli impianti cartari nel maggio 2007 e una serie d'interviste a operatori del settore. / This works examines the effects of environmental policies on the eco-innovation process. The theories analyzing the relationship between environmental policy intervention, the choice of instruments, their role as innovation drivers are discussed and a great number of ex-post empirical analysis of the effects of policy intervention on the environmental innovation process are evaluated. The analysis of the effects of environmental policies and innovation is applied to the case of the European union emission trading scheme (EU ETS). EU ets was introduced by directive 2003/87/ec and is the cornerstone of the European climate policy. The design of EU ets and its application during the period 2005-2007 are examined. The response of the Italian paper industry to the introduction of EU ets and its innovation effects are examined through the development of a case study, based on the results of a questionnaire submitted to the Italian paper plants subjected to EU ets.
162

Anaerobic digestion of pre-treated biological sludge from pulp and paper industry using heat, alkali and electroporation

Cardell, Lina January 2010 (has links)
The biological sludge formed in the pulp and paper wastewater treatment constitutes a costlyproblem to dispose off due to poor dewaterability. It is often incinerated or used as soilconditioner improvement. By using anaerobic digestion of the biological sludge, thedewaterability can be increased. Thanks to the formation of biogas, the sludge volume isdecreased and energy can be recovered as methane. By pre-treating the sludge, the biogasproduction can be increased, making the anaerobic digestion more economically feasible. Eleven samples of biological sludges from six Swedish pulp and paper mills, chosen torepresent different types and sizes of mills available in Sweden, were pre-treated with alkali(NaOH, pH12), heat (80˚C, 1 hr) and electroporation (2000 pulses, 10 kV/cm). Initialmethane production rate and methane potential of all sludges and pre-treatments weredetermined using batch experiment. A combination of two sludges (from the same mill) pretreatedwith alkali and heat was further investigated in a semi-continuous digester experiment. The batch experiments showed that alkali pre-treatment had the greatest positive effect onmethane production. Heat treatment performed second best, whereas electroporation had no orlittle effect. Overall, pre-treatments increased the initial methane production rate, but withinsignificant effects on the methane potential. Heat pre-treatment showed no difference inbiogas production compared to the control in the semi-continuous digester experiment. Alkalitreatment was shown to inhibit biogas production and cause high accumulation of acetate. Itcould not be concluded whether it was an effect from hydroxide or sodium ion addition.Further analysis of the NaOH impact on floc structure, toxicity and bioavailability issuggested to determine the suitability of alkali-treated sludge for anaerobic digestion. / Bioslam, som bildas vid vattenreningen på pappers- och massabruk, utgör en kostnad attomhänderta på grund av avvattningssvårigheter. Kvittblivning sker oftast genom förbränningeller användning som jordförbättringsmedel. Genom rötning kan slammet bli merlättavvattnat och tack vare att det bildas biogas minskar slamvolymen samtidigt som energikan utvinnas från metanet. Produktionen av biogas kan ökas genom att förbehandla slammetinnan rötning, vilket skulle innebära ekonomiska fördelar. Denna studie har undersökt effekten av förbehandling för elva bioslam från sex svenskapappers- och massabruk, valda att representera olika typer och storlekar på svenska bruk.Behandlingen gjordes med alkali (NaOH, pH12), värme (80˚C, 1 h) och elektroporering(2000 pulser, 10 kV/cm). Effekten av förbehandling på initial metanproduktionshastighet ochmetanpotential undersöktes med hjälp av satsvis utrötning (batch) av alla slam. Enkombination av två slam från samma burk utvärderades i ett semi-kontinuerligt rötningsförsökefter förbehandling med värme och alkali. Resultatet från utrötningsförsöket visade att den alkaliska förbehandlingen hade störst positivinverkan på metanproduktionen. Värmebehandlingen presterade näst bäst, medanelektroporeringen visade sig ha liten eller ingen effekt. Generellt sett ökade den initialametanproduktionshastigheten till följd av förbehandling, medan metanpotentialen förblevoförändrad. Värmebehandling gav ingen effekt på biogasproduktionen i det semikontinuerligarötningsförsöket jämfört med kontroll, medan alkalisk förbehandling inhiberadebiogasproduktionen och orsakade höga koncentrationer av ackumulerat acetat. Det kunde inteavgöras huruvida det var natrium- eller hydroxidjoner, som orsakade inhiberingen. För attkunna utvärdera möjligheten att röta slam, som förbehandlats med NaOH, rekommenderasvidare analys av dess påverkan på flockstruktur, toxicitet och biotillgänglighet.
163

Does market concentration motivate pulp and paper mills to vertically integrate?

Wang, Gewei 02 September 2005 (has links)
Following sound economic theory, paper mills vertically integrate into pulp production, partly because internalizing the production of their inputs allows them to avoid transaction costs. Higher market concentration, a proxy of higher asset specificity and transaction costs, should encourage vertical integration in the pulp and paper industry. However, this relationship has not been robust in previous studies or in our replication with updated FPL-UW data. Upon a deeper analysis of the data, this study should clarify the mechanism by which transaction cost can induce vertical integration in this particular industry, which does not have well-defined intermediate goods markets. In order to specify the pulp markets where paper mills are likely to trade, we construct a mill-specific concentration measure as a substitute to traditional regional concentration measures. We also narrow our sample to mills producing free sheet paper, the most profitable paper grade in this industry. With such model refinement, this research exhibits a significantly positive correlation between transaction cost and vertical integration.
164

Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators

Gauthier, Francis. January 2000 (has links)
Coliform bacteria have long been used to indicate fecal contamination of food, water, and solid surfaces, and thus the presence of a health hazard. In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were shown to support the growth of numerous coliforms, especially Klebsiella spp, Escherichia coli, Enterobacter spp., and Citrobacter spp . Mill coliforms were shown to be not just simple transients from feedwater or furnish (wood), but to be continuously growing, especially in the primary clarifiers. Therefore, coliforms and fecal coliforms cannot be used as fecal contamination indicators in pulp and paper mill water and effluent treatment systems. / N2-fixing coliform populations were detected in mill water systems and were analyzed using N2-fixation assays and nitrogenase gene (nifH) probing. Both active in situ populations and cultured microbial isolates were tested. Active N2-fixation was demonstrated in six primary clarifiers. Measurement of the numbers and composition of the total culturable bacterial community in a primary clarifier revealed that approximately 50% of all aerobic cells contained nifH , of which >90% were Klebsiella. Coliforms growing on MacConkey agar plates from the primary clarifier were all identified as Klebsiella and 100% of these Klebsiella contained the nifH gene. Preliminary estimates indicate that the amount of N2 fixed per day is substantial in some clarifiers.
165

Perceptions of the forestry industry : a case study of Sappi forests in Richmond.

Mwale, Chimika. January 2000 (has links)
Commercial forestry in South Africa was born out of the need to alleviate the growing demand on limited natural resources. From small beginnings, the industry has grown over the years and currently plays a significant role in South Africa's economy. The industry is a source of employment, foreign exchange and it facilitates a number of downstream processing activities. However, with the growth of the industry, there has also been increasing concern from various sectors over the impacts of the industry on the environment, particularly on water and biodiversity. More recently, concern has also shifted towards challenging the social and economic benefits of timber to local communities. As a result of growing pressure, legislation, policies and institutions have been transformed to ensure that environmental and social issues are taken into consideration in carrying out any form of development. The forestry industry has also changed considerably and understanding stakeholders perceptions has also become evident. In 1995 as part of the process to adhere to ISO 14001 international standards, Sappi forests commissioned a study to enable them to have a better understanding of activities, products and services which could have an impact on the environment. The concerns of the stakeholder were incorporated into their management plan. In continued efforts to improve the image of the forestry industry, this study was commissioned in 1999 with the aim of understanding how peoples perceptions of the industry had changed since 1995. The change of perceptions was determined through structured as well as semi structured interviews. A comparison between the responses in this study with those in Murphy et al. 1995 was undertaken to determine how peoples perceptions had changed since 1995. Even though the forestry industry had included some of the concerns raised by stakeholder and improved their management plans since 1995, peoples perceptions ofthe industry were largely negative. External changes leading to increased awareness in the intervening period were seen as the reason for the lack of change in peoples perceptions. Among others the external changes include increased transformation of environmental legislation both internationally and nationally which is more focused on addressing social as well as environmental issues. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.
166

A policy analysis of cleaner technology : a case study of Mondi Limited.

Mokoena, Kgauta Sylvester. January 2003 (has links)
The pollution problems resulting from industrial production activities result in the deterioration of our natural environment. That is why something needs to be done in order to preserve our environment. Conservation alone is not enough. Development is needed. Waste minimisation through applying Cleaner Technologies can help the country in the reduction of waste production and improve industry's environmental management processes. This study was based on an investigation into the adoption of Cleaner Technology. The study argues that elements of Cleaner Technology and the application of tools and strategies to practice Cleaner Technology are very useful for any industry. The costs of Cleaner Technology to companies cannot be compared with the benefits they can get from adopting Cleaner Technology. Mondi Limited concentrates on the product element of Cleaner Technology. It applies the recycling and re-use strategies in or~er to achieve product modification and input substitution. The organisation and knowledge elements are very strong and supportive to the technique element that is used at the Mondi Paper Mill. These three elements contribute to the increased efficiency, improved quality of intended products and waste minimisation through re-use and recycling. The question emerges about what government can or should do in return to companies like Mondi since they contribute towards the sustainability of our natural resources. / Thesis (M.Soc.Sc.)-University of Natal, Pietermaritzburg, 2003.
167

From wood to waste and waste to wood : aspects on recycling waste products from the pulp mill to the forest soil /

Rothpfeffer, Caroline, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
168

Avaliação operacional da estação de tratamento de efluentes de uma indústria de papel / Evaluation of operating conditions a paper mill wastewater treatment plant

Brandão, Marina Domingos 20 January 2014 (has links)
Made available in DSpace on 2015-03-26T13:28:34Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3222494 bytes, checksum: 78618fcec354fb9b93e356bb7523df94 (MD5) Previous issue date: 2014-01-20 / In the pulp and paper industry there is a large consumption of water in their processes which are directly linked to the issue of wastewater and characteristics of these effluents . Normally these industries treat their effluents by biological processes such as activated sludge and aerated lagoons . The treatment system aerated lagoons are classified as optional or complete mixing due to the power density of the aeration equipment . This study analyzes the performance of a complete-mix aerated lagoon followed by decantation pond of Santher paper mill located in Governador Valadares, Minas Gerais. Checks the current status of the treatment system with respect to flow, hydraulic detention time (HDT), power density, temperature and the availability of dissolved oxygen (DO) provided by nine aerators. The volumetric flow measurement method was used to determine a rate of 2419 m3/day, with corresponding and TDH's of 8.76 and 1.87 for the aeration and settling ponds, respectively. The temperatures did not exhibit large variations within each pond, the aerators indicated power density of 3.12 W/m3, a value close to the recommended minimum degree, and DO concentrations on the surface of the pond aeration above the recommended minimum, yet close the bottom of the pond, DO levels were observed in the range of 0 to 2.0 mg/L.. Physico-chemical characterization of the effluent was performed and compared to standards for effluent discharge in force in the State of Minas Gerais. Removal efficiencies of COD, BOD, TSS and oil and grease were 82%, 83%, 95% and 84%, respectively. Nitrogen and phosphorus were found in excess in the lagoons. The final effluent did not present acute toxicity to Daphnia similis or chronic toxicity to Ceriodaphnia dubia. The soluble COD removal coefficent for the complete mix aerated lagoon was estimated to be 0,23/day. Specific ultraviolet absorbance ( SUVA 254 ) of the effluent decreased at each stage of treatment, while UV 254 /UV 280 values remained constant throughout the system. The study also examined the occurrence of browning and odor generation in the settling pond, where the episodes were associated with lack of oxygen in the pond triggering anaerobic condition. / Na indústria de papel há grande consumo de água em seus processos, o que gera grande emissão de águas residuárias com diferentes características. Normalmente, essas indústrias tratam seus efluentes por processos biológicos como lodos ativados e lagoas aeradas. Os sistemas de tratamento por lagoas aeradas são classificados como aeradas facultativas ou de mistura completa, em função da densidade de potência dos equipamentos de aeração. O presente estudo analisa o desempenho de uma lagoa aerada de mistura completa seguida de lagoa de decantação da fábrica de papel SANTHER, situada em Governador Valadares-MG . Verificou-se a atual situação do sistema de tratamento com relação à vazão, tempo de detenção hidráulica, densidade de potência, temperaturas e disponibilidade de oxigênio dissolvido, fornecido por 9 aeradores. Utilizando-se o método volumétrico de medição de vazão foi medida uma vazão de 2419 m3/dia, e os TDH ́s de 8,76 e 1,87 dias para as lagoas de aeração e decantação, respectivamente. As temperaturas não apresentaram grandes variações no interior de cada lagoa, os aeradores indicaram densidade de potência de 3,12 W/m3, valor próximo ao mínino recomendado, e OD com concentrações na superfície da lagoa de aeração superiores ao mínimo recomendado, porém, próximo ao fundo da lagoa, foram constatados teores de OD na faixa de 0 a 2,0 mg/L. Foi realizada uma caracterização físico-química do efluente e comparado aos padrões de lançamento de efluentes vigentes nos Estado de Minas Gerais. As eficiências de remoção de DQO, DBO, SST e óleos e graxas foram de 82%, 83%, 95% e 84%, respectivamente. Nitrogênio e fósforo apresentaram-se em excesso no efluente da lagoa aerada. O efluente final não apresentou toxicidade aguda à Daphnia similis e nem toxicidade crônica à Ceriodaphnia dúbia. O valor do coeficiente da DQO solúvel estimado para a lagoa aerada de mistura completa foi de 0,23/d. A absorvância ultravioleta específica (SUVA254) aumentou ao longo do sistema de tratamento, enquanto os valores de UV254/UV280 permaneceram constantes. O estudo também analisou a ocorrência de escurecimento e geração de odor na lagoa de decantação, em que os episódios foram associados a falta de oxigênio na lagoa desencadeando a condição de anaerobiose.
169

Sistemas de certificação florestal no setor de papel e celulose : influências no desempenho exportador

Fischer, Bruno Brandão January 2008 (has links)
A crescente preocupação mundial com o manejo dos recursos florestais tem exercido grande pressão nos ambientes extrativistas e industriais ligados à base produtiva silvícola. Em vista da dificuldade de se estabelecer quais empresas e produtores adotam padrões produtivos ambientalmente sustentáveis, o uso das certificações tem ganhado notoriedade, funcionando como mecanismo de sinalização de comportamento mercadologicamente valorizado. Este cenário representa empiricamente teorizações da Economia da Informação em um ambiente agroindustrial específico, apresentando ferramentas de emissão de sinais como potenciais redutores da assimetria de informação presente na estrutura econômica de comércio. Contudo, permanecem questionamentos sobre como este uso de certificações e conseqüente melhoria da disponibilidade informacional podem impactar sobre as firmas adotantes desta estratégia. Relacionando esta situação com elementos da Economia Industrial (abordagem Estrutura-Conduta-Desempenho) e caracterizando a sinalização como um elemento de Conduta, esta pesquisa se propõe a verificar empiricamente potenciais impactos desta estratégia de atuação no Desempenho resultante. Como objeto específico de estudo, elegeu-se, dentro da indústria silvícola brasileira, o setor de papel e celulose, dada a sua relevância econômica para o agronegócio brasileiro. O método de análise de desenvolve através de modelos econométricos que buscam estabelecer e mensurar relações de influência entre a evolução de adoção de certificações de manejo florestal sustentável no desempenho exportador agregado do setor para o período 1995- 2008 (dados mensais), visto que a prática de comércio internacional potencializa a disponibilidade assimétrica de informações. Os resultados encontrados são parcialmente conclusivos em direção à sustentação da hipótese de que o uso de certificações tem influências positivas sobre o desempenho de comércio exterior da indústria brasileira de papel e celulose. / World’s increasing concern regarding forest resources management has pressured the producers and industries connected to forestry activities. In face of the difficulty to differentiate agents’ productive patterns of behavior towards forests, the use of sustainable forest management certifications is becoming increasingly relevant, working as a supposedly market valued signaling device. This scenario represents empirically in a specific agroindustrial environment the theories developed in Information Economics, presenting signal emission tools as potential reducers of commercial information asymmetry. However, questions regarding how the use of these certifications and the consequent improvement of information availability impact on firms which adopt this strategy remain. Relating this situation with the elements of Industrial Economics (more specifically the Structure-Conduct-Performance approach) and defining the signaling behavior as a Conduct pattern, this research proposes an analysis of the possible impacts of this strategy in the resulting Performance. As object of study, the Brazilian Pulp & Paper (P&P) industry is chosen, given its economic importance for the country’s forest and agribusiness sectors. The methodology to develop this verification is based on econometric regression models, aiming to establish and measures influences between the sustainable forest management certifications implementation evolution in the aggregated exporting performance of the Brazilian P&P industry for the period 1995-2008 (monthly data), since the international trade is expected to rise the levels of information asymmetry and hence the value of signals. Results allow partial acceptance of the hypothesis that the use of certifications has positive influences on Brazilian P&P industry’s international trade performance.
170

[en] CIRCULAR ECONOMY IN THE PULP INDUSTRY: REUSE OF DREGS AND GRITS WASTE / [pt] ECONOMIA CIRCULAR NA INDÚSTRIA DE CELULOSE TIPO KRAFT: APROVEITAMENTO DE RESÍDUOS DREGS E GRITS

DANIELLE REIS SOARES 14 January 2019 (has links)
[pt] Pesquisas recentes apontam que o Brasil ocupa lugar de destaque no ranking mundial de produção de papel e celulose. O setor é fundamental para economia nacional e é responsável por gerar diversos empregos diretos e indiretos. Porém, apesar de a madeira, principal matéria prima do processo produtivo, ser proveniente de florestas plantadas, as empresas do setor se deparam com problemas de cunho ambiental em função da grande quantidade de resíduos sólidos industriais gerados diariamente em suas fábricas, os quais, apresentam potencial de causar danos ambientais. Desta forma, o setor sofre com o forte apelo ambiental da sociedade, dos órgãos fiscalizadores e do mercado. Este fato tem levado as empresas a buscarem soluções alternativas para o descarte dos seus resíduos, com o intuito de valorizar e garantir um novo uso aos mesmo, ao invés, da simples disposição em aterro, levando em conta os conceitos e princípios da Economia Circular. Neste sentido buscou-se estudar na literatura os potenciais meios de valorização para os resíduos dregs e grits e, como resultado, encontrou-se utilizações dos mesmos como corretivos de acidez de solo e fertilizantes, estabilização de áreas degradadas, aplicação em obras rodoviárias, utilização na indústria de cerâmica e de cimento e na utilização como agregados em argamassas. Buscou-se também averiguar as práticas atuais adotadas por empresas do setor e os benefícios alcançados por elas como, por exemplo, a melhoria da imagem da empresa, redução do passivo ambiental e dos custos de transporte e disposição dos resíduos. / [en] Nowadays, the strong environmental, social and economic appeal faced by the industrial sector have been contributing to the development of studies and research aimed at finding alternatives to the use of solid waste generated in its processes, in order to add value to them and to minimize the amount of waste sent to landfills, promoting improvement in the environmental performance of their processes and still favoring their image in the market, especially in the international market. In this way the Circular Economy arises. According to Ellen MacArthur Foundation (2013), the Circular Economy is restorative and regenerative by principle, arises precisely to put an end to the current linear industrial model, considered as pipe end, in which, the raw material extracted from nature is processed, consumed and discarded after use. The goal of Circular Economy is to keep products, components and materials at their highest level of usefulness and value, all the time. The model distinguishes between technical and biological cycles. Consumption happens only in biological cycles, where food and biologically-based materials (such as cotton or wood) are designed to feed back into the system through processes like composting and anaerobic digestion. These cycles regenerate living systems, such as soil, which provide renewable resources for the economy. Technical cycles recover and restore products, components, and materials through strategies like reuse, repair, remanufacture or (in the last resort) recycling (Ellen MacArthur Foundation (2013). The circular economy incorporates ideas from different schools of thought as the regenerative design, cradle to cradle, industrial ecology, economy of performance, biomimicry, and the blue economy; This model of economy is based on three principles: nature as model, nature as a measure and nature as a mentor.

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