Comparative study of green and synthetic polymers for enhanced oil recovery

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Several publications by authors in the field of petrochemical engineering have examined the use of chemically enhanced oil recovery (CEOR) technology, with a specific interest in polymer flooding. Most observations thus far in this field have been based on the application of certain chemicals and/or physical properties within this technique regarding the production of 50–60% trapped (residual) oil in a reservoir. However, there is limited information within the literature about the combined effects of this process on whole properties (physical and chemical). Accordingly, in this work, we present a clear distinction between the use of xanthan gum (XG) and hydrolyzed polyacrylamide (HPAM) as a polymer flood, serving as a background for future studies. XG and HPAM have been chosen for this study because of their wide acceptance in relation to EOR processes. To this degree, the combined effect of a polymer’s rheological properties, retention, inaccessible pore volume (PV), permeability reduction, polymer mobility, the effects of salinity and temperature, and costs are all investigated in this study. Further, the generic screening and design criteria for a polymer flood with emphasis on XG and HPAM are explained. Finally, a comparative study on the conditions for laboratory (experimental), pilot-scale, and field-scale application is presented

Hydrogen storage in depleted gas reservoirs: A comprehensive review

Hydrogen future depends on large-scale storage, which can be provided by geological formations (such as caverns, aquifers, and depleted oil and gas reservoirs) to handle demand and supply changes, a typical hysteresis of most renewable energy sources. Amongst them, depleted natural gas reservoirs are the most cost-effective and secure solutions due to their wide geographic distribution, proven surface facilities, and less ambiguous site evaluation. They also require less cushion gas as the native residual gases serve as a buffer for pressure maintenance during storage. However, there is a lack of thorough understanding of this technology. This work aims to provide a comprehensive insight and technical outlook into hydrogen storage in depleted gas reservoirs. It briefly discusses the operating and potential facilities, case studies, and the thermophysical and petrophysical properties of storage and withdrawal capacity, gas immobilization, and efficient gas containment. Furthermore, a comparative approach to hydrogen, methane, and carbon dioxide with respect to well integrity during gas storage has been highlighted. A summary of the key findings, challenges, and prospects has also been reported. Based on the review, hydrodynamics, geochemical, and microbial factors are the subsurface\u27s principal promoters of hydrogen losses. The injection strategy, reservoir features, quality, and operational parameters significantly impact gas storage in depleted reservoirs. Future works (experimental and simulation) were recommended to focus on the hydrodynamics and geomechanics aspects related to migration, mixing, and dispersion for improved recovery. Overall, this review provides a streamlined insight into hydrogen storage in depleted gas reservoirs

Date-leaf carbon particles for green enhanced oil recovery

Green enhanced oil recovery (GEOR) is an environmentally friendly enhanced oil recovery (EOR) process involving the injection of green fluids to improve macroscopic and microscopic sweep efficiencies while boosting tertiary oil production. Carbon nanomaterials such as graphene, carbon nanotube (CNT), and carbon dots have gained interest for their superior ability to increase oil recovery. These particles have been successfully tested in EOR, although they are expensive and do not extend to GEOR. In addition, the application of carbon particles in the GEOR method is not well understood yet, requiring thorough documentation. The goals of this work are to develop carbon nanoparticles from biomass and explore their role in GEOR. The carbon nanoparticles were prepared from date leaves, which are inexpensive biomass, through pyrolysis and ball-milling methods. The synthesized carbon nanomaterials were characterized using the standard process. Three formulations of functionalized and non-functionalized date-leaf carbon nanoparticle (DLCNP) solutions were chosen for core floods based on phase behavior and interfacial tension (IFT) properties to examine their potential for smart water and green chemical flooding. The carboxylated DLCNP was mixed with distilled water in the first formulation to be tested for smart water flood in the sandstone core. After water flooding, this formulation recovered 9% incremental oil of the oil initially in place. In contrast, non-functionalized DLCNP formulated with (the biodegradable) surfactant alkyl polyglycoside and NaCl produced 18% more tertiary oil than the CNT. This work thus provides new green chemical agents and formulations for EOR applications so that oil can be produced more economically and sustainably

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Challenges of Trachoma Control: An Assessment of the Situation in Northern Nigeria

Over the last three decades, a lot has been achieved in the control of trachoma worldwide. New assessment techniques, effective evidence-based control strategy with new methods and drugs, and an aggressive global partnership for the control of the disease have evolved. As such the number of people with the disease and blindness due to the disease had drastically reduced. Trachoma is now only responsible for about 4% of blindness worldwide down from 12% some few decades ago. Some countries are on the verge of eliminating the disease as a public health problem. Despite these achievements numerous challenges remain for achieving trachoma control in endemic communities. This article highlights the challenges faced in one of the known trachoma endemic areas – northern Nigeria. Aspects on the dearth of complete situational data on trachoma, fragmented implementation of the SAFE strategy, community apathy, difficulties faced in ensuring safe, and quality lid surgery in the most difficult terrain where the disease thrives are discussed here. Other unique challenges like managing children with severe trichiasis, curbing the high rate of early-onset recurrence of trichiasis after lid rotation surgery and challenges to maintain supply of antibiotics and implementation of facial cleanliness and environmental improvement components of the control strategy are presented along with the learnt experiences and recommendations. These challenges and their remedies are likely to be shared by other trachoma endemic areas in Africa

Wykorzystanie energii w kuchni w Bauchi w Nigerii

Energy has remained essential for cooking services by households through their kitchen. The source of this energy has remained multiple in nature, with a concise order of it being Modern or Traditional. This study through a survey, using four points scale and chi-square test of association of energy utilization by households in the University staff quarters explored the cooking energy so as to acknowledge the energy type used by households. The incentive for use and its impact on users and established that with a high level of education, only 9% of the households use LPG as a modern form of energy while the choice for Electricity and Kerosene has remained foremost in use by the household. The household size was noted to encourage the quantum of energy consumed as well as the persistent use of inferior energy like firewood which was penultimate looked as a rural energy. The study concludes that household in the study area use multiple energy sources to support their cooking activities due to affordability and it being dependable and easily obtainable even though not very durable and effective. It is noted that the study area has not obeyed the theory of utilizing the energy ladder concept.Energia pozostaje kluczową kwestią z punktu widzenia przygotowywania posiłków przez gospodarstwa domowe w ich kuchniach. W naturze istnieje wiele źródeł tej energii, z typowym podziałem na nowoczesne i tradycyjne. W niniejszym artykule zbadano rodzaje źródeł energii wykorzystywanych do gotowania przez gospodarstwa domowe pracowników uniwersyteckich w Bauchi w Nigerii, wykorzystując w tym celu badania ankietowe oraz czteropunktową skalę testu chi-kwadrat. Koncentrując się na bodźcach do wyboru oraz efektach wykorzystywania źródeł energii wśród osób z wysokim poziomem wykształcenia, ustalono, że jedynie 9% badanych gospodarstw domowych korzysta z LPG jako nowoczesnego źródła energii, natomiast głównym źródłem pozostaje elektryczność oraz nafta. Wielkość gospodarstw domowych wpływała na ilość zużywanej energii, a także na wykorzystywanie źródeł gorszej jakości, jak np. drewno. We wnioskach stwierdzono, że analizowane gospodarstwa domowe wykorzystują do gotowania różne źródła energii, zależnie od możliwości finansowych oraz dostępności, a mniejsza uwagę poświęcają ich trwałości oraz efektywności. Należy zauważyć, że w obszarze badawczym nie stosowano teorii wykorzystującej koncepcję drabiny energetycznej (ang.: energy ladder concept)

Wykorzystanie energii w kuchni w Bauchi w Nigerii

Energy has remained essential for cooking services by households through their kitchen. The source of this energy has remained multiple in nature, with a concise order of it being Modern or Traditional. This study through a survey, using four points scale and chi-square test of association of energy utilization by households in the University staff quarters explored the cooking energy so as to acknowledge the energy type used by households. The incentive for use and its impact on users and established that with a high level of education, only 9% of the households use LPG as a modern form of energy while the choice for Electricity and Kerosene has remained foremost in use by the household. The household size was noted to encourage the quantum of energy consumed as well as the persistent use of inferior energy like firewood which was penultimate looked as a rural energy. The study concludes that household in the study area use multiple energy sources to support their cooking activities due to affordability and it being dependable and easily obtainable even though not very durable and effective. It is noted that the study area has not obeyed the theory of utilizing the energy ladder concept.Energia pozostaje kluczową kwestią z punktu widzenia przygotowywania posiłków przez gospodarstwa domowe w ich kuchniach. W naturze istnieje wiele źródeł tej energii, z typowym podziałem na nowoczesne i tradycyjne. W niniejszym artykule zbadano rodzaje źródeł energii wykorzystywanych do gotowania przez gospodarstwa domowe pracowników uniwersyteckich w Bauchi w Nigerii, wykorzystując w tym celu badania ankietowe oraz czteropunktową skalę testu chi-kwadrat. Koncentrując się na bodźcach do wyboru oraz efektach wykorzystywania źródeł energii wśród osób z wysokim poziomem wykształcenia, ustalono, że jedynie 9% badanych gospodarstw domowych korzysta z LPG jako nowoczesnego źródła energii, natomiast głównym źródłem pozostaje elektryczność oraz nafta. Wielkość gospodarstw domowych wpływała na ilość zużywanej energii, a także na wykorzystywanie źródeł gorszej jakości, jak np. drewno. We wnioskach stwierdzono, że analizowane gospodarstwa domowe wykorzystują do gotowania różne źródła energii, zależnie od możliwości finansowych oraz dostępności, a mniejsza uwagę poświęcają ich trwałości oraz efektywności. Należy zauważyć, że w obszarze badawczym nie stosowano teorii wykorzystującej koncepcję drabiny energetycznej (ang.: energy ladder concept)