Process optimization of the flaring gas for field applications

During petroleum industry operations, burning flammable gas components in the flaring stacks is common, normally a symbol for stable production, but flaring these components creates harmful emissions for the environment. This flaring gas has components with a high quantity of heating power, an important measurement that quantifies the energy that can potentially be obtained from this wasted resource. This paper aims to evaluate the energy usage of the flaring gas, estimating the possible energy produced with this usable resource by modeling a treatment and energy generation process employing the Aspen HYSYS® simulator. The flaring gas is characterized using different models and compositional ranges of natural gas to know what kind of gas it is and identify what type of equipment could be used for treatment and energy generation from this resource. After the gas characterization, the selection of the equipment of treatment and energy generation is necessary; this is done using a multicriteria analysis by taking into consideration the variables of gas composition, electrical efficiency, economic performance, and GHG emissions, ensuring to generate the greatest amount of energy possible to be produced with this flaring gas. By increasing the LHV, 0.95 MMSCF of flared gas of an oilfield in the VMM basin produced 5133 kW, enough energy to supply gas treatment and power generation facilities and four times the total gross consumption energy of a model oilfield in the basin, while the CO2 emissions were reduced 11.4%, and cost savings using this resource instead of diesel were obtained. In conclusion, to minimize flaring and to recover and reuse these waste components, looking for alternatives for the use of this gas-like power generation is an important option that reduces pollutants emission, gives a new source of fuel, and gives an energy usefulness to this wasted resource.This research was funded by PROPESQ/UFPB research edit N◦001/2022 of the Federal University of Paraiba (UFPB). The O.H.A.J. was funded by the Brazilian National Council for Scientific and Technological Development (CNPq), grant numbers 407531/2018-1 and 303293/2020-9. The F.S. was funded by the Brazilian National Council for Scientific and Technological Development (CNPq), grant number 307588/2020-3. The research was also partially supported by the Portuguese FCT with project reference UIDB/00690/2020 and SusTEC (LA/P/0007/2020). João Paulo Carmo was supported by a PQ scholarship with the reference CNPq 304312/2020-7info:eu-repo/semantics/publishedVersio

Nanoadsorbentes para captura de dióxido de carbono (CO2): un enfoque a la purificación del biogás

Nos últimos anos, a produção de biogás em biodigestores domésticos vem crescendo, sendo utilizado nas áreas rurais principalmente para iluminação e aquecimento. No entanto, a presença de CO2 reduz consideravelmente o valor calorífico do biogás, gerando uma diminuição na eficiência térmica, o que torna necessário remover esse componente para melhorar a qualidade do gás e aumentar suas possibilidades de aplicação como combustível. Neste trabalho, avaliou-se a capacidade de adsorção de CO2 de nanopartículas de sílica e sílica pirogênica Aerosil 380 funcionalizadas com aminas. Nanopartículas de sílica foram preparadas pelo método sol-gel usando ortossilicato de tetraetil (TEOS) como precursor do silício. Os materiais foram funcionalizados por impregnação úmida com 15 e 30 %p de dietanolamina e etilenodiamina. Os testes de caracterização permitiram determinar o tamanho das nanopartículas (TEM), a área superficial (BET), a estabilidade térmica (TGA) e a composição química (FTIR) das nanoestruturas e relacionar essas propriedades à afinidade pelo adsorbato. Os testes de adsorção de CO2 foram realizados a uma temperatura de 30 °C sob um fluxo de 60 mLmin-1 de CO2 a uma pressãode 20 psi. Os materiais baseados em sílica pirogênica aerossil 380 obtiveram uma maior capacidade de adsorção em comparação com as nanopartículas de sílica sintetizadas, obtendo a maior capacidade de adsorção (35,4 mg/g) para a amostra impregnada de 30 %p de dietanolamina, que também pode adsorver CO2 na presença de umidade.In recent years, the production of biogas in domestic biodigesters has been growing, being used in rural areas mainly for lighting and heating. Nevertheless, the presence of CO2 considerably reduces the calorific value of biogas, generating a decrease in thermal efficiency which makes it necessary to remove this component to improve the quality of the gas and increase its possibilities of application as fuel. In this research, the CO2 adsorption capacity of Aerosil 380 commercialized pyrogenic silica nanoparticles with amines was evaluated. Silica nanoparticles were prepared by the sol-gel method using tetraethyl orthosilicate (TEOS) as a precursor to silicon oxide or silica. The materials were functionalized by wet impregnation with 15 and 30 %w of diethanolamine and ethylenediamine. The characterization tests allowed us to determine the nanoparticle size (TEM), surface area (BET), thermal stability (TGA) and chemical composition (FTIR) of the nanostructures and to relate these properties to the affinity for adsorbate. The CO2 adsorption tests were carried out at a temperature of 30 °C under a flow of 60 mLmin-1 of CO2 at a pressure of 20 psi. Pyrogenic Aerosil 380 based silica materials obtained a higher adsorption capacity compared to synthesized silica nanoparticles, obtaining the highest adsorption capacity (35.4 mg/g) for the 30 %w impregnated sample of diethanolamine, which can also adsorb CO2 in the presence of H2O.En los últimos años, la producción de biogás en biodigestores domésticos ha tenido un creciente desarrollo, siendo empleado en zonas rurales principalmente para iluminar y calentar. Sin embargo, la presencia de CO2 reduce considerablemente el poder calorífico del biogás, lo cual genera disminución en la eficiencia térmica, lo que hace necesaria la remoción de este componente para mejorar la calidad del gas y aumentar sus posibilidades de aplicación como combustible. En este trabajo se evaluó la capacidad de adsorción de CO2 de nanopartículas de sílice y sílice pirogénica comercial Aerosil 380 funcionalizadas con aminas. Las nanopartículas de sílice se prepararon mediante el método sol-gel usando como precursor de silicio tetraetil ortosilicato (TEOS). Los materiales se funcionalizaron mediante impregnación húmeda con 15 y 30 %p de dietanolamina y etilendiamina. Las pruebas de caracterización permitieron determinar el tamaño de nanopartícula (TEM), área superficial (BET), estabilidad térmica (TGA) y composición química (FTIR) de las nanoestructuras, y relacionar dichas propiedades con la afinidad por el adsorbato. Los ensayos de adsorción de CO2 se realizaron a una temperatura de 30 °C bajo un flujo de 60 mLmin-1 de CO2 a una presión de 20 psi. Los materiales basados en sílice pirogénica Aerosil 380 obtuvieron una mayor capacidad de adsorción comparados con los materiales de nanopartículas de sílice sintetizadas, y se obtuvo la mayor capacidad de adsorción (35,4 mg/g) para la muestra impregnada al 30 % p/p de dietanolamina, que además puede adsorber CO2 en presencia de humedad

Dinámica de fluidos computacional como herramienta para el diseño de micromodelos para la evaluación de inyección de surfactantes en procesos de recobro mejorado

Se usó la dinámica de fluidos computacional (CFD) con el fin de proponer una guía para el diseño de dispositivos de microfluídica donde la diferencia entre dos surfactantes con propiedades similares en el rango ultra bajo de tensión interfacial se haga mas evidente durante procesos de recuperación química mejorada de petróleo (CEOR). En la inyección de surfactantes, uno de los métodos CEOR más ampliamente aplicados, el objetivo es disminuir la tensión interfacial de las fases presentes en el yacimiento. Las simulaciones de CFD se llevaron a cabo utilizando el método multifásico Volume of Fluid (VOF) para una geometría de un medio poroso con un mallado triangular generado a partir del software Meshing presente en el paquete de simulación de Ansys. El análisis CFD consideró el efecto de la tensión interfacial de dos surfactantes (0.037 mN /m y 0.045 mN/ m) sobre el factor de recobro, el tiempo de ruptura, la dimensión fractal del patrón de flujo, la caída de presión y el efecto de entrampamiento. Las propiedades de los dispositivos de microfluídica que se abordaron en la simulación fueron porosidad (50% -70%), forma de grano (circular e irregular), presencia o ausencia de fracturas y velocidad de inyección (10 ft/day - 30 ft/day). La metodología descrita en la guía indica que, para el par de surfactantes seleccionados, un micromodelo con una porosidad de 0.5, granos circulares, la presencia de una fractura y el funcionamiento a la velocidad máxima de inyección (30 pies / día) podría identificar mejor las diferencias en el rendimiento de ambos surfactantes. La guía desarrollada en esta investigación facilitará el diseño de micromodelos al acoplar esta tecnología con técnicas de simulación de CFD.Computational fluid dynamics (CFD) was used to propose a guide for the design of a microfluid device that would make more evident differences in the performance of surfactants with similar properties in the ultra-low range of interfacial tension during Chemical Enhanced Oil Recovery (CEOR). In surfactant injection, one of the most widely applied CEOR methods, the objective is to decrease the interfacial tension of the phases present in the reservoir. The CFD simulations were carried out using the Volume of Fluid (VOF) method for a fully meshed porous geometry generated using a triangular mesh from the Meshing software present in the Ansys simulation package. The CFD analysis considered the effect of the interfacial tension of two surfactants (0.037 mN/m and 0.045 mN/m) on the oil recovery factor, the breakthrough time, the fractal dimension of the flow pattern, the pressure drop, and the entrapment effect. The properties of the microfluid system that were addressed in the simulation were porosity (50%-70%), grain shape (circular and irregular), presence or absence of fractures, and injection velocity (10 ft/day - 30 ft/day). The methodology described in the guide indicates that for the pair of surfactants selected, a microfluid device with a porosity of 0.5, circular grains, the presence of a fracture and operating at the maximum injection velocity (30 ft/day) could better identify differences in the performance of both surfactants. The guide developed in this research will facilitate the design of micromodels by coupling this technology with CFD simulation techniques.Línea de Investigación (Research field): Enhanced Oil RecoveryMaestrí