A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions
A worldwide problem reported by oil companies is the plugging of flowlines because of gas hydrates, a crystal that forms and agglomerates causing partial or complete obstructions. This incurs in revenue losses because of production stop, and also relates to safety and environmental risks. The main p...
| Autor principal: | Bassani, Carlos Lange |
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| Idioma: | Português |
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Universidade Tecnológica Federal do Paraná
2021
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riut-1-246992021-04-09T06:11:50Z A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions Abordagem multiescala de hidratos de gás considerando estrutura, cinética de crescimento, aglomeração e transportabilidade em condições de escoamento multifásico Bassani, Carlos Lange Morales, Rigoberto Eleazar Melgarejo https://orcid.org/0000-0003-3297-7361 http://lattes.cnpq.br/5156573817670917 Cameirão, Ana https://orcid.org/0000-0001-9214-9950 Morales, Rigoberto Eleazar Melgarejo https://orcid.org/0000-0003-3297-7361 http://lattes.cnpq.br/5156573817670917 Marcelino Neto, Moises Alves https://orcid.org/0000-0001-5492-6640 http://lattes.cnpq.br/2071333457212415 Orlande, Helcio Rangel Barreto https://orcid.org/0000-0002-3511-322X http://lattes.cnpq.br/4195594302858278 Herri, Jean Michel https://orcid.org/0000-0003-2285-9070 Sum, Amadeu Kun Wan Escoamento multifásico Hidratos Cristalização Transferência de calor Aglomeração Fluidodinâmica computacional Métodos de Simulação Multiphase flow Hydrates Crystallization Heat transfer Agglomeration Computational fluid dynamics Simulation methods CNPQ::ENGENHARIAS::ENGENHARIA MECANICA::ENGENHARIA TERMICA Engenharia Mecânica A worldwide problem reported by oil companies is the plugging of flowlines because of gas hydrates, a crystal that forms and agglomerates causing partial or complete obstructions. This incurs in revenue losses because of production stop, and also relates to safety and environmental risks. The main production strategy consists in avoiding gas hydrates by, e.g., injecting a high volume of chemical inhibitors. In order to reduce production costs, a new strategy called hydrate management is at research, where hydrates are let form, but its stable flow needs to be assured. In this sense, a deep knowledge on off-equilibrium processes such as growth kinetics, agglomeration and transportability is required to design and manage pipelines. This thesis quantitatively describes part of these processes. Several multiscale concepts are gathered from multidisciplinary fields (heat and mass transfer, crystallization, porous media, multiphase flow), leading to new interpretations. Hydrates are porous, hydrophilic particles that act as sponges entrapping water, where crystallization occurs mainly in the capillary walls (1st new assumption). Permeation through the porous particles furnishes water to its outer surface, promoting liquid bridge formation after particles’ collision, which leads to agglomeration (2nd new assumption). Higher subcoolings are shown to promote faster sealing-up of the particles, decreasing permeation rates and causing the particles to be inert in the agglomeration-sense (called dry particles). Furthermore, additives with surfactant properties decrease the permeation rate, which explains their anti-agglomerant effects. Several mechanisms are discussed upon modeling growth kinetics and agglomeration and by further coupling with a steadystate multiphase flow model. The model sensitivity evidences that a general classification of the system can be done in four distinct types of limiting phenomena: active surface-limited, dissolution-limited, heat transfer-limited, and pressure drop-limited. For engineering purposes, the model is simplified into a dimensionless criterion that determines stable production in oil-dominant systems, having the shape of Ba ∞ Da Re -n , which relates the Damköhler and Reynolds dimensionless groups graphical abstract). This expression still needs future testing in order to retrieve the exact shape of the dimensionless groups. An absolute form that depends on subcooling, water cut, mixture velocity and interfacial properties is nevertheless proposed and preliminary test shows agreement with experimental data. This criterion evidences that, once hydrates form in oil-continuous systems, the faster the particles seal-up, the quicker the particles turn dry, and the smaller the stable agglomerate size, thus requiring smaller mixture velocities in order for particles to remain suspended. Another dimensionless group La = f (Da,Re) is proposed to further explain particle-wall interactions into predicting deposition for future studies. If ever these two new dimensionless groups show consistent in future testing and fitting against larger databases, they will represent an important advance on how engineers design flowlines using the hydrate management strategy. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Petróleo Brasileiro (Petrobrás) Um problema reportado mundialmente pelas companhias de petróleo é a obstrução das linhas de produção devido à formação de hidratos de gás, um cristal que se forma e aglomera ocasionando restrições parciais ou totais. Isso leva à perda de ganho de capitais devido à parada de produção, e também pode ocasionar riscos ambientais e de segurança. A principal estratégia de produção consiste em evitar a formação de hidratos pela injeção de um volume consideravelmente grande de inibidores químicos. Visando a redução dos custos de produção, uma nova estratégia está em pesquisa, chamada de gerenciamento de hidratos (hydrate management). Esta consiste em deixar os hidratos se formar, porém em garantir (gerenciar) o seu escoamento estável sem nenhuma obstrução. Esta estratégia necessita de um conhecimento mais aprofundado dos processos fora do equilíbrio, tais como a cinética de crescimento, a aglomeração e a transportabilidade dos cristais. Esta tese descreve de uma maneira quantitativa parte destes processos. Vários conceitos multidisciplinares (transferência de calor e massa, cristalização, meio poroso, escoamento multifásico) e provenientes de diferentes escalas são explorados nesta tese, o que leva a novas interpretações dos fenômenos físicos. Os cristais de hidratos são porosos e hidrofílicos e portanto atuam como esponjas que aprisionam água, sendo que a cristalização ocorre principalmente nas paredes dos seus capilares (1ª nova consideração). A permeabilidade através da partícula porosa fornece água à sua superfície externa, promovendo a formação de pontes de líquido após a colisão entre partículas, o que leva à aglomeração (2ª nova consideração). Subresfriamentos mais altos se mostram capazes de promover um selamento rápido das partículas, diminuindo a taxa de permeabilidade e promovendo partículas inertes à aglomeração, chamadas partículas secas (dry particles). Além disso, aditivos com propriedades surfactantes diminuem a taxa de permeabilidade, o que explica o efeito antiaglomerante dos mesmos. Diversos mecanismos são discutidos a partir da modelagem da cinética de crescimento e da aglomeração de hidratos a partir de um balanço populacional acoplado a um modelo de escoamento multifásico em regime permanente. Testes de sensibilidade do modelo evidenciam uma classificação geral dos sistemas em função de quatro tipos de processos de limitação da cristalização: pelo decrescimento da superfície ativa de cristalização, pela dissolução de gás, pela transferência de calor ou pela queda de pressão. Para aplicações de engenharia, o modelo é simplificado a um critério adimensional que determina a produção estável em sistema óleo-dominante, possuindo a forma Ba ∞ Da Re -n , que relaciona os números de Damköhler e Reynolds (resumo gráfico). Esta expressão ainda necessita de mais testes para determinar o formato exato dos grupos adimensionais. Porém, uma forma absoluta (dimensional) para este critério é proposta em função do subresfriamento, da fração de água, da velocidade da mistura e das propriedades interfaciais, e apresenta concordância em comparações preliminares com dados experimentais. Este critério evidencia que, quando os hidratos de gás se formam em sistemas óleo-dominante, quanto mais rápido for o selamento da partícula, mais rápido a mesma se tornará seca, promovendo aglomerados menores e, portanto, requerendo menores velocidades para estabilizar a suspensão. Outro grupo adimensional La = f (Da,Re) é proposto para explicar interações entre partícula e parede e com aplicação para modelagem de deposição de hidratos em trabalhos futuros. Se o uso destes dois novos grupos adimensionais se mostrar consistente quando comparados e regredidos com bases de dados mais extensas, espera-se atingir um novo marco em como as linhas de produção de óleo e gás são projetadas. 2021-04-08T18:41:15Z 2021-04-08T18:41:15Z 2020-12-17 doctoralThesis BASSANI, Carlos Lange. Abordagem multiescala de hidratos de gás considerando estrutura, cinética de crescimento, aglomeração e transportabilidade em condições de escoamento multifásico. 2020. Tese (Doutorado em Engenharia Mecânica e de Materiais) - Universidade Tecnológica Federal do Paraná, Curitiba, 2020. http://repositorio.utfpr.edu.br/jspui/handle/1/24699 por openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf Universidade Tecnológica Federal do Paraná Curitiba Brasil Programa de Pós-Graduação em Engenharia Mecânica e de Materiais UTFPR |
| institution |
Universidade Tecnológica Federal do Paraná |
| collection |
RIUT |
| language |
Português |
| topic |
Escoamento multifásico Hidratos Cristalização Transferência de calor Aglomeração Fluidodinâmica computacional Métodos de Simulação Multiphase flow Hydrates Crystallization Heat transfer Agglomeration Computational fluid dynamics Simulation methods CNPQ::ENGENHARIAS::ENGENHARIA MECANICA::ENGENHARIA TERMICA Engenharia Mecânica |
| spellingShingle |
Escoamento multifásico Hidratos Cristalização Transferência de calor Aglomeração Fluidodinâmica computacional Métodos de Simulação Multiphase flow Hydrates Crystallization Heat transfer Agglomeration Computational fluid dynamics Simulation methods CNPQ::ENGENHARIAS::ENGENHARIA MECANICA::ENGENHARIA TERMICA Engenharia Mecânica Bassani, Carlos Lange A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| description |
A worldwide problem reported by oil companies is the plugging of flowlines because of gas hydrates, a crystal that forms and agglomerates causing partial or complete obstructions. This incurs in revenue losses because of production stop, and also relates to safety and environmental risks. The main production strategy consists in avoiding gas hydrates by, e.g., injecting a high volume of chemical inhibitors. In order to reduce production costs, a new strategy called hydrate management is at research, where hydrates are let form, but its stable flow needs to be assured. In this sense, a deep knowledge on off-equilibrium processes such as growth kinetics, agglomeration and transportability is required to design and manage pipelines. This thesis quantitatively describes part of these processes. Several multiscale concepts are gathered from multidisciplinary fields (heat and mass transfer, crystallization, porous media, multiphase flow), leading to new interpretations. Hydrates are porous, hydrophilic particles that act as sponges entrapping water, where crystallization occurs mainly in the capillary walls (1st new assumption). Permeation through the porous particles furnishes water to its outer surface, promoting liquid bridge formation after particles’ collision, which leads to agglomeration (2nd new assumption). Higher subcoolings are shown to promote faster sealing-up of the particles, decreasing permeation rates and causing the particles to be inert in the agglomeration-sense (called dry particles). Furthermore, additives with surfactant properties decrease the permeation rate, which explains their anti-agglomerant effects. Several mechanisms are discussed upon modeling growth kinetics and agglomeration and by further coupling with a steadystate multiphase flow model. The model sensitivity evidences that a general classification of the system can be done in four distinct types of limiting phenomena: active surface-limited, dissolution-limited, heat transfer-limited, and pressure drop-limited. For engineering purposes, the model is simplified into a dimensionless criterion that determines stable production in oil-dominant systems, having the shape of Ba ∞ Da Re -n , which relates the Damköhler and Reynolds dimensionless groups graphical abstract). This expression still needs future testing in order to retrieve the exact shape of the dimensionless groups. An absolute form that depends on subcooling, water cut, mixture velocity and interfacial properties is nevertheless proposed and preliminary test shows agreement with experimental data. This criterion evidences that, once hydrates form in oil-continuous systems, the faster the particles seal-up, the quicker the particles turn dry, and the smaller the stable agglomerate size, thus requiring smaller mixture velocities in order for particles to remain suspended. Another dimensionless group La = f (Da,Re) is proposed to further explain particle-wall interactions into predicting deposition for future studies. If ever these two new dimensionless groups show consistent in future testing and fitting against larger databases, they will represent an important advance on how engineers design flowlines using the hydrate management strategy. |
| format |
Tese |
| author |
Bassani, Carlos Lange |
| author_sort |
Bassani, Carlos Lange |
| title |
A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| title_short |
A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| title_full |
A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| title_fullStr |
A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| title_full_unstemmed |
A multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| title_sort |
multiscale approach for gas hydrates considering structure, growth kinetics, agglomeration, and transportability under multiphase flow conditions |
| publisher |
Universidade Tecnológica Federal do Paraná |
| publishDate |
2021 |
| citation |
BASSANI, Carlos Lange. Abordagem multiescala de hidratos de gás considerando estrutura, cinética de crescimento, aglomeração e transportabilidade em condições de escoamento multifásico. 2020. Tese (Doutorado em Engenharia Mecânica e de Materiais) - Universidade Tecnológica Federal do Paraná, Curitiba, 2020. |
| url |
http://repositorio.utfpr.edu.br/jspui/handle/1/24699 |
| _version_ |
1805299301706891264 |
| score |
10,814766 |