No abstract

As a result of rising economies and environmental constraints, the demand for clean and renewable sources of energy is fast increasing. Biogas is a renewable form of energy that fits all expectations in terms of delivery, cost, and greenhouse emissions reduction. Biogas utilization is advantageous because it is a means of creating wealth from daily human, agricultural, household and municipal waste that could otherwise be polluting the environment as waste is deposited on a daily basis which are potential biogas sources; it is not dependent on weather conditions as other renewable forms (solar and wind). Biogas can also be compressed, stored and transported, and therefore easily responds to changes in demand. This paper entails the use of nano-structured membranes to upgrade biogas (which contains primarily methane and carbon dioxide). The benefits of membranes include their compact structure and ease of usage with low maintenance, their low running costs and minimal loss of the upgraded gas. 15nm, 200nm and 6000nm membranes were used to ascertain the flux of the model biogas mixture passing through it under various operating conditions. In each case, the exit flowrate of methane was higher than that of carbon dioxide and this is attributed to the pore sizes of the membrane and its ability to filter the heavier gases. The results show that the molecular weight of the gases also play a role in their permeation rate as it follows the Knudsen regime.

The use of membranes for gas upgrading has increasingly become of interest as it has shown great potential for efficient and affective gas purification and a pathway to green energy. The emission of greenhouse gases to the atmosphere has detrimental effects on the economy in terms of global warming which has led to many natural disasters, heat waves, food shortage, loss of life and property. To combat this, studies of capturing and utilizing greenhouse gases are ongoing. In this paper, the study of biogas components (methane and carbon dioxide) diffusion through membranes are studied to employ its use as a solution for the challenge. The study involved the use of membranes of different pore sizes (15, 200 and 6000nm) to ascertain the flow characteristics and regime of the gases under different operating conditions. Single gas permeation tests were conducted, and the results show the flow of gases is dependent on factors including molecular weight, kinematic diameter and viscosity of the gas components. It was observed that pressure has a greater influence on the gas flow through membranes compared to temperature with the effect of pore size having the greatest impact. The flux of methane through the membrane is greater than that of carbon dioxide in regular pore geometry and depicts a greater potential for upgrading of biogas.

The mobility profiles of gases used in enhanced oil recovery (EOR) have been thoroughly investigated through the coupling operations of data mining of oilfield data and experimental data analyses. Mobility as an EOR objective function has not been previously applied to characterize potential reservoirs for EOR selection and application, even though it is a robust combinatorial function that benefits from two petrophysical variables, permeability and viscosity. The data mining approach identified mobility as a reliable objective function for reservoir characterisation. The data distribution and clustering results indicate that Gas EOR reservoirs have relatively higher mean mobility than Thermal, Microbial and Chemical EOR reservoirs. The experimental approach investigated EOR gases, CO 2 , CH 4 , N 2 , and Air. A modified Darcy Equation of State for gas flow through porous media was applied to evaluate which gas would competitively attain the oil displacement optimisation criterion for mobility ratio, M ≤ 1. Coupling the data mining with the experimental data results reveals that gas reservoirs can be further categorized by mobility. CH 4 (18.16 mD/cp) was observed to have the highest mobility followed by Air (14.60 mD/cp), N 2 (13.61 mD/cp), and CO 2 (12.96 mD/cp). The gas mobility order significantly corresponds with the mobility distribution of reservoirs that implemented gas EOR processes. It was concluded that CO 2 offers relatively lower mobility, therefore, it is the most competitive EOR gas to approach the mobility ratio criterion of unity or less.

The program starts on Sunday (August 8th) with two panel discussion sessions, one on “Energy, Environment and Economy” and the other one on “Energy and Education” where current challenges, potential solutions, opportunities and future directions are discussed by the leading experts. The program opens its technical sessions on Monday with the formal opening talks where the TUBA President, Minister of Industry and Technology, and Minister of Energy and Natural Resources deliver their speeches. The program continues with 29 plenary/ keynote speakers, 27 invited speakers and over 121 general speakers on four days which make an exceptionally designed conference in the area of energy science and technology. It then ends on Thursday (August 12th) with a panel discussion session and closing remarks. Furthermore, there are general sessions where many research talks are delivered by researchers, scientists, engineers, and technologists to disseminate high-quality research results and present new findings. Local and global online participations are expected from academia, government agencies, and industry to bring all players together, and the conference is then expected to lead to effective and fruitful discussions and collaborations among these attendants from different disciplines, institutes, and sectors from all over the world. Moreover, it is planned to have some special issues in various reputable international journals to publish high-quality papers out of the conference.