Experimental Evaluation of Locally Synthesized Biodiesel Drilling Fluid

Diesel oil has been the preferred base fluid for the formulation of oil-based drilling mud. Diesel oil has negative effects on the environment and there is a growing need for more environmentally sustainable alternatives that can be technically compared to diesel base oil. In recent times, the use of vegetable oils as drilling fluid base oil has been of interest. In this study, 1378 kg/m3 of palm kernel oil-based mud (PKOBM) and palm kernel oil biodiesel based mud (BDBM) were experimentally formulated. BDBM was synthesized by the transesterification of vegetable (palm kernel) oil. The performance of PKOBM and BDBM was then evaluated against conventional diesel oil-based mud (DOBM). The evaluation performed was based on the rheological, filtration and wall building properties, emulsion and thermal stabilities, and acute toxicity of the formulated drilling fluid systems. The results obtained from the study reveal that the mud systems (PKOBM and BDBM) show a typical Herschel-Bulkley (modified power-law) drilling mud rheological pattern at temperatures of 49°C, 66°C and 80°C. BDBM showed comparable rheological properties with better hole cleaning capacity as indicated by a lower flow index. For the filtrate loss test, BDBM exhibited a slightly lower filtrate loss compared to DOBM, whereas PKOBM had a higher fluid loss of 4.4 ml. For the filter cake and thermal stability test, there were no significant changes between DOBM and BDBM, whereas PKOBM had the least desirable performance. BDBM exhibited the most stable emulsion of 1274 volts breaking voltage and PKOBM, the least with 739 volts compared to 1169 volts breaking voltage of DOBM. This study concludes that BDBM could be used as an environmentally sustainable substitute for diesel oil-based mud (DOBM).Sažetak: Kao bazni fluid za pripremu isplake na bazi ulja najčešće se upotrebljava dizelsko ulje. Dizelsko ulje ima negativan utjecaj na okoliš i sve je veća potreba za ekološki održivijim alternativama koje se s tehničkoga aspekta mogu usporediti s dizelskim baznim uljem. U novije se vrijeme istražuje mogućnost upotrebe biljnih ulja kao baznoga ulja u isplakama. U ovome istraživanju eksperimentalno su pripremljene isplaka (gustoće 1378 kg/m3) na bazi palmina ulja (ulje iz palminih koštica) (PKOBM) i isplaka na bazi biodizela dobivenoga iz palmina ulja (BDBM). BDBM je dobiven transesterifikacijom biljnoga (palmina) ulja. Zatim je napravljena usporedba karakteristika PKOBM-a i BDBM-a i konvencionalne isplake na bazi dizelskoga ulja (DOBM). Isplake su uspoređene na temelju reoloških i filtracijskih svojstava, sposobnosti stvaranja isplačnoga obloga, stabilnosti emulzije, toplinske stabilnosti te akutne toksičnosti. Rezultati dobiveni istraživanjem upućuju na to da isplake PKOBM i BDBM pokazuju tipično Herschel-Bulkley (modificirani eksponencijalni (power-law) model) reološko ponašanje pri temperaturama od 49 °C, 66 °C i 80 °C. BDBM je pokazao usporediva reološka svojstva uz bolji kapacitet iznošenja krhotina nego što bi na to upućivao niži indeks protoka. U testu gubitka filtrata isplake BDBM je pokazao nešto manji gubitak filtrata u odnosu na DOBM, dok je PKOBM imao veći gubitak filtrata, koji je iznosio 4,4 ml. Ispitivanja isplačne obloge (filter cake) i termičke stabilnosti nisu pokazala znatnije razlike između DOBM-a i BDBMa, dok je PKOBM imao najmanje poželjne performanse. U usporedbi stabilnosti emulzija BDBM je pokazao najstabilniju emulziju (destabilizacija emulzije pri naponu od 1274 V), a PKOBM najmanje stabilnu emulziju (destabilizacija pri 739 V), dok u slučaju DOBM-a do destabilizacije emulzije dolazi pri naponu od 1169 V. Temeljem provedenih istraživanja zaključeno je da bi se BDBM mogao koristiti kao ekološki održiva zamjena za isplaku na bazi dizelskoga ulja (DOBM)

Effect of direct current on gas condensate droplet immersed in brine solution

Environmentally sustainable methods of extracting hydrocarbons from the reservoir are increasingly becoming an important area of research. Several methods are being applied to mitigate condensate banking effect which occurs in gas condensate reservoirs; some of which have significant impact on the environment (subsurface and surface). Electrokinetic enhanced oil recovery (EEOR) increases oil displacement efficiency in conventional oil reservoirs while retaining beneficial properties to the environment. To successfully apply this technology on gas condensate reservoirs, the behavior of condensate droplets immersed in brine under the influence of electric current need to be understood. A laboratory experiment was designed to capture the effect of electrical current on interfacial tension and droplet movement. Pendant drop tensiometry was used to obtain the interfacial tension, while force analysis was used to analyze the effect of the electrical current on droplet trajectory. Salinity (0–23 ppt) and electric voltage (0–46.5 V) were the main variables during the entire experiment. Results from the experiment reveal an increase in IFT as the voltage is increased, while the droplet trajectory was significantly altered with an increase in voltage. This study concludes that the interfacial tension increases progressively with an increase in DC current, until its effect counteracts the benefit obtained from the preferential movement of condensate droplet.Petroleum Technology Development Fund, under grant number PTDF/ED/PHD/PPI/1028/17

Which Offers Greater Techno-Economic Potential: Oil or Hydrogen Production from Light Oil Reservoirs?

Data Availability Statement: The data are available on request.Supplementary Materials: The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/geosciences15060214/s1. References [18,31,32,52,54,69,70,71,72,73,74] are cited in the supplementary materials.The global emphasis on clean energy has increased interest in producing hydrogen from petroleum reservoirs through in situ combustion-based processes. While field practices have demonstrated the feasibility of co-producing hydrogen and oil, the question of which offers greater economic potential, oil, or hydrogen, remains central to ongoing discussions, especially as researchers explore ways to produce hydrogen exclusively from petroleum reservoirs. This study presents the first integrated techno-economic model comparing oil and hydrogen production under varying injection strategies, using CMG STARS for reservoir simulations and GoldSim for economic modeling. Key technical factors, including injection compositions, well configurations, reservoir heterogeneity, and formation damage (issues not addressed in previous studies), were analyzed for their impact on hydrogen yield and profitability. The results indicate that CO2-enriched injection strategies enhance hydrogen production but are economically constrained by the high costs of CO2 procurement and recycling. In contrast, air injection, although less efficient in hydrogen yield, provides a more cost-effective alternative. Despite the technological promise of hydrogen, oil revenue remains the dominant economic driver, with hydrogen co-production facing significant economic challenges unless supported by policy incentives or advancements in gas lifting, separation, and storage technologies. This study highlights the economic trade-offs and strategic considerations crucial for integrating hydrogen production into conventional petroleum extraction, offering valuable insights for optimizing hydrogen co-production in the context of a sustainable energy transition. Additionally, while the present work focuses on oil reservoirs, future research should extend the approach to natural gas and gas condensate reservoirs, which may offer more favorable conditions for hydrogen generation.This research received no external funding

Development of the Hydrogen Market and Local Green Hydrogen Offtake in Africa

Data Availability Statement: All data generated or analyzed during this study are included in this published article.Creating a hydrogen market in Africa is a great opportunity to assist in the promotion of sustainable energy solutions and economic growth. This article addresses the legislation and regulations that need to be developed to facilitate growth in the hydrogen market and allow local green hydrogen offtake across the continent. By reviewing current policy and strategy within particular African countries and best practices globally from key hydrogen economies, the review establishes compelling issues, challenges, and opportunities unique to Africa. The study identifies the immense potential in Africa for renewable energy, and, in particular, for solar and wind, as the foundation for the production of green hydrogen. It examines how effective policy frameworks can establish a vibrant hydrogen economy by bridging infrastructural gaps, cost hurdles, and regulatory barriers. The paper also addresses how local offtake contracts for green hydrogen can be used to stimulate economic diversification, energy security, and sustainable development. Policy advice is provided to assist African authorities and stakeholders in the deployment of enabling regulatory frameworks and the mobilization of funds. The paper contributes to global hydrogen energy discussions by introducing Africa as an eligible stakeholder in the emerging hydrogen economy and outlining prospects for its inclusion into regional and global energy supply chains.This research received no external funding

In situ hydrogen production from hydrocarbon reservoirs - modelling study

The use of hydrogen is gaining reputation because of its many beneficial properties to the environment in comparison to hydrocarbon not minding its net energy requirement for production challenges. With most countries adopting a strategy to achieve their net-zero emissions targets, it becomes much more important to find affordable, low-carbon ways of producing hydrogen. An innovative method of producing hydrogen from hydrocarbon reservoirs while keeping the associated by-products in the reservoir has been demonstrated researchers from the University of Calgary. However, in this study, a framework for designing an in situ combustion model that considers four key hydrogen forming reactions – steam reforming, partial oxidation, autothermal reforming and pyrolysis, was developed. A set of non-linear equations obtained from chemical equilibrium analysis of the hydrogen forming reactions were solved using a Newton-Jacobi interation. Analysis of the change in Gibbs free energy of each reaction were then used as a screening tool for implementing a numerical model. Results obtained from the combustion model were then validated against results obtained from thermal reservoir simulator CMG STARS. Results from the model reveal an upward trending sinusoidal relationship between steam-carbon ratio and the amount of hydrogen yield from an in situ hydrogen production study. The combustion model could be used as a framework to design experimental analysis.Petroleum Technology Development Fund, under grant number PTDF/ED/PHD/PPI/1028/17