@PhDThesis{Tessarolo:2017:VaApVa,
author = "Tessarolo, Luciana de Freitas",
title = "Modelo num{\'e}rico para libera{\c{c}}{\~o}es de {\'o}leo e
g{\'a}s em {\'a}guas profundas: valida{\c{c}}{\~a}o e
aplica{\c{c}}{\~o}es em vazamentos hipot{\'e}ticos",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2017",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2017-08-23",
keywords = "vazamento de {\'o}leo e g{\'a}s, modelo de vazamento de
{\'o}leo e g{\'a}s, plumas subaqu{\'a}ticas, jatos e plumas de
{\'o}leo e g{\'a}s, {\'o}leo e g{\'a}s em {\'a}guas
profundas. oil and gas blowout, model for oil and gas blowout,
underwater plumes, jets and plumes of oil and gas, oil and gas in
deepwater.",
abstract = "O crescimento da produ{\c{c}}{\~a}o mundial de petr{\'o}leo e
g{\'a}s natural {\'e} motivo de aten{\c{c}}{\~a}o devido ao
risco de ocorrerem acidentes que resultem em consequ{\^e}ncias
danosas para a popula{\c{c}}{\~a}o, para a economia e para o
meio ambiente. Uma importante ferramenta que pode ser utilizada
para auxiliar na elabora{\c{c}}{\~a}o de planos de
conting{\^e}ncia para o atendimento de emerg{\^e}ncias
envolvendo vazamentos {\'e} a modelagem num{\'e}rica.
Atrav{\'e}s da simula{\c{c}}{\~a}o de diversos cen{\'a}rios, o
comportamento da pluma de {\'o}leo e g{\'a}s pode ser
determinado, proporcionando agilidade para as tomadas de
decis{\~a}o. Com base nessa import{\^a}ncia, o objetivo desse
trabalho foi construir um modelo num{\'e}rico Lagrangiano para
determinar o comportamento do {\'o}leo e do g{\'a}s em caso de
vazamentos a partir de {\'a}guas profundas. Nesse modelo, o modo
como as got{\'{\i}}culas de {\'o}leo e as bolhas de g{\'a}s
descrevem sua trajet{\'o}ria e interagem com o meio foi formulado
em dois est{\'a}gios: din{\^a}mico, no qual a din{\^a}mica
inicial da mistura de {\'o}leo, g{\'a}s, {\'a}gua e hidrato
determina o transporte da pluma, e advectivo-difusivo, no qual
processos de advec{\c{c}}{\~a}o e difus{\~a}o dominam o
transporte das part{\'{\i}}culas ap{\'o}s a pluma
alcan{\c{c}}ar o n{\'{\i}}vel de flutuabilidade neutra, onde o
est{\'a}gio din{\^a}mico torna-se negligenci{\'a}vel. Em cada
fase, os processos f{\'{\i}}sico-qu{\'{\i}}micos que alteram a
massa e a concentra{\c{c}}{\~a}o dos componentes da pluma foram
considerados. Primeiramente, o modelo num{\'e}rico foi validado
utilizando experimentos de laborat{\'o}rio e de campo, avaliando
isoladamente os processos de entranhamento de {\'a}gua,
forma{\c{c}}{\~a}o/dissolu{\c{c}}{\~a}o/decomposi{\c{c}}{\~a}o
de hidrato, dissolu{\c{c}}{\~a}o de g{\'a}s e {\'o}leo, e
escape do g{\'a}s a partir da pluma. Para todos os
par{\^a}metros analisados, os resultados fornecidos pelo modelo
concordaram de forma satisfat{\'o}ria com os valores observados.
Em seguida, para avaliar o modelo considerando os processo
combinados, um experimento com descargas reais de plumas de
{\'o}leo/g{\'a}s/{\'a}gua a partir de {\'a}guas profundas foi
simulado, sendo obtidas trajet{\'o}rias semelhantes {\`a}quelas
observadas. Ap{\'o}s a valida{\c{c}}{\~a}o do modelo, foram
realizadas simula{\c{c}}{\~o}es de vazamentos hipot{\'e}ticos
de {\'o}leo e g{\'a}s em po{\c{c}}os atualmente em fase de
produ{\c{c}}{\~a}o nos Campos de Frade - Bacia de Campos e de
Lula - Bacia de Santos. Em cada po{\c{c}}o, foram simuladas
descargas nos meses de Janeiro/2016 e Julho/2016, a fim de se
verificar o efeito da varia{\c{c}}{\~a}o sazonal do meio no
comportamento da pluma. Os resultados mostraram que as
trajet{\'o}rias do {\'o}leo e do g{\'a}s seguiram a
dire{\c{c}}{\~a}o das correntes oce{\^a}nicas. Para os
experimentos no Campo de Frade (Exps. CF-JAN e CF-JUL), as maiores
got{\'{\i}}culas de {\'o}leo foram as primeiras a
alcan{\c{c}}ar a superf{\'{\i}}cie, 2 h ap{\'o}s o
in{\'{\i}}cio da descarga, enquanto que as menores ascenderam de
forma mais lenta, emergindo ap{\'o}s 6, 7 h. Desde o fundo do mar
at{\'e} z = \−300 m, o {\'o}leo deslocou-se para
Noroeste. Acima dessa profundidade, as got{\'{\i}}culas seguiram
para as dire{\c{c}}{\~o}es Sudeste e Sudoeste, respectivamente,
nos Exps. CF-JAN e CF-JUL, influenciadas pela invers{\~a}o das
correntes oce{\^a}nicas. Nos dois casos simulados, 6\% da massa
inicial do {\'o}leo foram dissolvidas no meio durante seu
deslocamento na coluna de {\'a}gua. O comportamento das bolhas de
g{\'a}s em ambos os experimentos foi bastante semelhante. O
g{\'a}s contido nas bolhas foi completamente convertido em
cristais de hidrato logo nos primeiros minutos. As bolhas seguiram
a dire{\c{c}}{\~a}o Noroeste, atingindo a profundidade
m{\'a}xima de z = \−545 m e tendo a massa de g{\'a}s
completamente dissolvida no meio em um intervalo de 2 h. Nos dois
experimentos no Campo de Lula (Exps. CL-JAN e CL-JUL), enquanto as
got{\'{\i}}culas maiores levaram cerca de 2, 6 h para chegar em
superf{\'{\i}}cie, as de menor tamanho afloraram 7, 6 h
ap{\'o}s o in{\'{\i}}cio da libera{\c{c}}{\~a}o. No Exp.
CL-JAN (CL-JUL), o {\'o}leo deslocou-se para Noroeste (Sudoeste)
at{\'e} z = \−600 m (z = \−400 m), mudando para
Sudeste (levemente para Noroeste) acima dessa profundidade,
seguindo as varia{\c{c}}{\~o}es na dire{\c{c}}{\~a}o das
correntes. Ao computar a dissolu{\c{c}}{\~a}o do {\'o}leo na
coluna de {\'a}gua, verificou-se que 9, 3% da massa inicial foram
perdidas para o meio. Nessas duas simula{\c{c}}{\~o}es no Campo
de Lula, a cobertura de hidrato tamb{\'e}m foi rapidamente
formada ao redor das bolhas de g{\'a}s. As bolhas deslocaram-se
para Noroeste (Sudoeste) no Exp. CL-JAN (CL-JUL) e n{\~a}o
afloraram em superf{\'{\i}}cie. O g{\'a}s foi completamente
dissolvido no meio em um intervalo de 2, 95 h e a profundidade
m{\'a}xima alcan{\c{c}}ada pelas bolhas foi z = \−611 m
(z = \−576 m). ABSTRACT: The growth of the world production
of oil and natural gas increases the risk of accidents resulting
in harmful consequences for the population, the economy and the
environment. An important tool that can be used to elaborate
contingency plans for the emergency treatment involving blowouts
is the numerical modeling. From the simulation of several
scenarios, the behavior of the oil and gas plume can be
determined, providing agility in the decision making. Motivated by
these necessities, the objective of this research was to build a
Lagrangian numerical model to assess the behavior of the oil and
gas in case of deepwater blowouts. In this model, how the oil
droplets and gas bubbles describe their trajectory and interact
with the environment was formulated in two stages: dynamic, in
which the initial dynamics of the mixture of oil, gas, water and
hydrate determines the plume transport, and advection-diffusion,
in which advection and diffusion processes govern the particles
transport after the plume reaches the neutral buoyancy level,
where the dynamic stage becomes negligible. In each phase, the
physical-chemical processes that change the mass and the
concentration of the plume components were considered. First, the
numerical model was validated using laboratory and field
experiments, evaluating separately the processes of entrainment of
water, formation/dissolution/decomposition of hydrate, oil and gas
dissolution, and separation of gas from the plume. For all the
analyzed processes, the model reproduced satisfactorily the
observations. Afterwards, all processes were considered in an
experiment simulating real deepwater discharges of
oil/gas/seawater, and the trajectories obtained were very similar
to those observed. After the model validation, simulations of
hypothetic blowouts of oil and gas from oil wells currently in
phase of production in Frade Oil Field - Campos Basin and Lula Oil
Field - Santos Basin were performed. In each oil well, discharges
were simulated on January/2016 and July/2016, in order to verify
the effects of the seasonal variation of the environment
conditions on the plume behavior. The results showed the oil and
gas trajectories following the direction of the ocean currents.
For the experiments in Frade Oil Field (Exps. CF-JAN and CF-JUL),
the biggest oil droplets were the first to reach the surface, 2 h
after the beginning of the discharge, while the smallest rose
slowly, emerging after 6.7 h. From the sea floor to z =
\−300 m, the oil moves toward the Northwest. Above this
depth, the droplets flowed Southeastward and Southwestward in
Exps. CF-JAN and CF-JUL, respectively, due to ocean currents
variations. In these two experiments, 6% of the initial mass of
oil were dissolved into the environment. The behavior of the gas
bubbles in both experiments was very similar. The gas inside the
bubbles was completely converted in hydrate crystals in the first
few minutes. The bubbles flowed Northwestward, reaching the
maximum depth of z = \−545 m and their gas mass was
completely dissolved into the environment in 2 h. For the two
experiments in Lula Oil Field (Exps. CL-JAN and CL-JUL), while the
biggest oil droplets spent about 2.6 h to reach the surface, the
smallest emerged 7.6 h after the beginning of the discharge. In
Exp. CL-JAN (CL-JUL), the oil moved toward the Northwest
(Southwest) until z = \−600 m (z = \−400 m),
changing toward the Southeast (lightly toward the Northwest) above
this depth, following the currents direction. About 9.3% of the
initial mass were lost to the environment. In these two
simulations in Lula Oil Field, hydrate shells were formed quickly
around the gas bubbles. In Exp. CL-JAN (CL-JUL), the bubbles
flowed Northwestward (Southwestward) and were fully dissolved into
the environment in 2.95 h and the maximum depth reached by the
bubbles was z = \−611 m (z = \−576 m).",
committee = "Chan, Chou Sin (presidente) and Innocentini, Valdir (orientador)
and Pezzi, Luciano Ponzi and Cabral, Marcelo Montenegro and
Miranda, Fernando Pellon de and Martins, Renato Parkinson and
Sartori Neto, Angelo",
englishtitle = "Numerical model for oil and gas releases from deepwater:
validation and applications in hypothetical blowouts",
language = "pt",
pages = "256",
ibi = "8JMKD3MGP3W34P/3PGB5GL",
url = "http://urlib.net/ibi/8JMKD3MGP3W34P/3PGB5GL",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}