Low Salinity Watertlooding: Effect of Fines Migration and Ion Type on Oil Recovery

This is a PhD thesis by publication that includes six published papers, five of which are journal papers and one is a full manuscript conference paper. The goal of this thesis is to investigate the effect of low salinity waterflooding (LSW) and salt ion type on enhancing oil recovery, which is implemented to select LSW reservoir candidates for a Wintershall Holding project. In addition, another aim of this thesis is to design a set of criteria to plan two-phase corefloods to accurately determine relative permeability by using Welge-JBN method. Low salinity water injection in oil fields has gained wide interest in the literature over the last two decades due to the fact that it is a cost-effective enhanced oil recovery technology. However, not only the mechanisms of LSW are not clearly understood, but there is some controversy around some LSW phenomena, especially fines migration, which is deemed to have the detrimental impact of formation damage in oil and gas reservoirs. This thesis focuses on the fines-migration mechanism of LSW and shows that it can be utilised to produce incremental oil using the induced formation damage in the reservoir. This study shows that micro-scale sweep efficiency is improved during low salinity waterflooding by flux diversion, that is caused by fines detachment and migration. Initially, clay particles are attached to the rock surface by electrostatic forces caused by the initial high-salinity formation water that saturates the rock. In this work, it is shown that injecting low salinity brine into the rock causes clay particles to be detached due to the weakening of electrostatic forces. As a result, fines migration results in blockage of high permeability water channels during high salinity water injection and diversion of the water flux to thin pores where residual oil is trapped. The results indicate that residual oil saturation was decreased by 5-18% in multiple low salinity coreflooding experiments with different salinity concentrations. Another part of this study investigates the effect of brine ion type on fines migration and oil recovery during LSW. It is demonstrated that having divalent ions such as calcium in the initial formation water, and the water injected into the porous media (including LSW), aids to stabilise fines due to the strong affinity and adsorption of such ions on the clay and rock surface. Deionised water injection confirms this, as hydrogen ions cannot exchange with calcium ions. This is confirmed by the fact that there are no clay particles in the effluent solution, no rise in pressure drop across the samples, and no detection of desorbed calcium ions in the Ion Chromatography results. Injection of low salinity sodium chloride solution, followed by deionised water flooding, induced desorption of the calcium ions, which then enabled clay particles to detach as a result of the weak electrostatic forces between clay and rock surface, that is caused by the sodium. This is important as it can be applied in controlling formation damage programs and preventing injectivity/production issues in oil and gas wells. Furthermore, enhanced oil recovery can also be achieved as proven by the incremental oil production observed when fines migration takes place in the two-phase flow tests due to the improved micro-scale sweep efficiency as explained above in the first part of the thesis. Moreover, a new set of criteria for coreflooding parameters to model relative permeability, for the experimental tests performed in this study, is introduced in this thesis and can, also, be applied in any two-phase flow experiments. These criteria are essential as they are needed for valid determination of relative permeability by the Welge-JBN method. They fulfil the assumption of low capillary-viscous ratio to achieve a large-scale approximation by optimising the core length and displacement rate. The numerical simulation results demonstrate that this ratio should not exceed 0.5 for the model to have valid relative permeability calculations by the Welge-JBN technique. The criteria include capillary number, precision of water-cut measurement, sampling period, and pressure measurement accuracy, which are critical to plan any coreflood tests to achieve accurate results.Thesis (Ph.D.) -- University of Adelaide, Australian School of Petroleum (ASP), 201

POLA SEBARAN DAN INDEKS EKOLOGI TERIPANG DI PERAIRAN ARMY DOCK DESA PANDANGA KABUPATEN PULAU MOROTAI

Teripang atau yang lebih dikenal dengan timun laut merupakan salah satu organisme dari filum echinodermata kelas Holothuroidea. Teripang (Holothuroidea) dapat di temukan atau dijumpai di seluruh perairan pantai mulai dari daerah pasang surut yang dangkal sampai perairan yang lebih dalam. Tujuan penelitian ini adalah untuk mengetahui Pola Sebaran dan Indeks Ekologi Teripang di perairan Desa Pandanga Kabupaten Pulau Morotai.Penelitian ini dilakukan pada bulan Oktober sampai November 2019 dengan menggunakan Metode Transek Kuadrat. Dimulai dengan pengambilan data teripang di Perairan Army Dock Desa Pandanga Kecamatan Morotai Selatan Kabupaten Pulau Morotai.Data yang diperoleh kemudian dianalisis menggunakan formula pola distribusi internal dan indeks ekologi keanekaragaman jenis, indeks dominasi, indeks kemerataan). Hasil analisis menunjukkan bahwa nilai keanekaragam stasiun I sampai III (0,68-0,90), kemerataan 0.618-0,985 dan dominasi 0,69-0,564. Penyebaran teripang pada semua stasiun penelitian menunjukkan pola penyebaran bersifat mengelompok dengan nilai >1

PENGARUH PERIKLANAN DAN FASILITAS TERHADAP KEPUTUSAN MENGINAP DI HOTEL GRAND DAFAM BELA TERNATE (STUDI PADA TAMU YANG MENGINAP DI HOTEL)

This study aims to examine the influence of advertising and facilities on the decision to stay at the grand hotel dafam Bela Ternate. The sample in this study amounted to 65 respondents. The sampling technique uses non probality sampling technique and the data collection technique used is by distributing questionnaires, interviews and observations. Data analysis in this study is using multiple regression analysis.  The results of this study  indicate  that  partially  the  Advertising Variables (X1), Facilities (X2), have a positive and significant effect on the decision to stay and simultaneously or together Advertising Variables (X1), Facilities (X2), influence the decision to stay at the Hotel Grand Dafam Bela Ternate

Healthy Home Concept According to Javanese Ethnic Panaragan Society: An Etnolinguistic Study

Javanese ethnic Panaragan culture is very diverse. One of them is the traditional Javanese ethnic Panaragan home. The home as a shelter is expected to bring outer and inner health to its inhabitants. The concept of a healthy house can be known to the mindset of the people contained in language. The theory used is ethnolinguistics which views language tends to reflect the mindset of a society. The method is used ethnoscience by analyzing linguistic utterances in the realm of building a healthy house. As a result, there are outer and inner concepts before building construction, healthy house space and griyowingking concept that reflects a healthy home mindset for the comfort and safety of a residence which is summarized in language patterns

TINGKAT PENGETAHUAN MASYARAKAT TENTANG PEMANFAATAN TANAMAN OBAT KELUARGA SEBAGAI MINUMAN HERBAL

Traditional medicine is a choice in treatment and maintaining stamina, especially during the COVID-19 pandemic. Family Medicinal Plants (TOGA) is one of the sources of traditional medicine that is easily obtained and can be used by families. However, inappropriate management and utilization of TOGA can cause TOGA's efficacy to decrease, but it can also cause an unacceptable taste when TOGA is consumed. Therefore, this time the community service offered a solution by providing counseling and training on the use of TOGA at the PKK Hamlet of Karang Tengah, Sleman, Yogyakarta. This counseling and training, it is hoped, will increase the knowledge and skills of PKK movers in properly using TOGA. Keywords:  COVID-19, TOGA, traditional medicine, herbal drink, wedang uwuhObat tradisional menjadi pilihan alternatif dalam pengobatan dan menjaga stamina, terutama pada kondisi pandemi COVID-19. Tanaman Obat Keluarga (TOGA) merupakan salah satu sumber obat tradisional yang mudah didapatkan dan dapat dimanfaatkan oleh keluarga. Namun demikian, pengelolaan dan pemanfaatan TOGA yang kurang tepat, ternyata dapat menyebabkan khasiat TOGA menurun, selain itu juga dapat menimbulkan rasa yang kurang dapat diterima ketika TOGA dikonsumsi. Oleh karena itu, pengabdian masyarakat kali ini menawarkan solusi dengan memberikan penyuluhan dan pelatihan pemanfaatan TOGA pada PKK Pedukuhan Karang Tengah, Sleman, Yogyakarta. Dengan adanya penyuluhan dan pelatihan ini diharapkan dapat meningkatkan pengetahuan dan keterampilan  ibu-ibu penggerak PKK dalam pemanfaatan TOGA dengan tepat. Kata kunci : COVID-19, TOGA, obat tradisional, minuman herbal, wedang uwu

Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990–2017: A systematic analysis for the Global Burden of Disease Study 2017

Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017) includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data. Methods: We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting. Findings: Globally, for females, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and haemoglobinopathies and haemolytic anaemias in both 1990 and 2017. For males, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and tuberculosis including latent tuberculosis infection in both 1990 and 2017. In terms of YLDs, low back pain, headache disorders, and dietary iron deficiency were the leading Level 3 causes of YLD counts in 1990, whereas low back pain, headache disorders, and depressive disorders were the leading causes in 2017 for both sexes combined. All-cause age-standardised YLD rates decreased by 3·9% (95% uncertainty interval [UI] 3·1-4·6) from 1990 to 2017; however, the all-age YLD rate increased by 7·2% (6·0-8·4) while the total sum of global YLDs increased from 562 million (421-723) to 853 million (642-1100). The increases for males and females were similar, with increases in all-age YLD rates of 7·9% (6·6-9·2) for males and 6·5% (5·4-7·7) for females. We found significant differences between males and females in terms of age-standardised prevalence estimates for multiple causes. The causes with the greatest relative differences between sexes in 2017 included substance use disorders (3018 cases [95% UI 2782-3252] per 100 000 in males vs 1400 [1279-1524] per 100 000 in females), transport injuries (3322 [3082-3583] vs 2336 [2154-2535]), and self-harm and interpersonal violence (3265 [2943-3630] vs 5643 [5057-6302]). Interpretation: Global all-cause age-standardised YLD rates have improved only slightly over a period spanning nearly three decades. However, the magnitude of the non-fatal disease burden has expanded globally, with increasing numbers of people who have a wide spectrum of conditions. A subset of conditions has remained globally pervasive since 1990, whereas other conditions have displayed more dynamic trends, with different ages, sexes, and geographies across the globe experiencing varying burdens and trends of health loss. This study emphasises how global improvements in premature mortality for select conditions have led to older populations with complex and potentially expensive diseases, yet also highlights global achievements in certain domains of disease and injury

Global, regional, and national age-sex-specific mortality and life expectancy, 1950-2017: a systematic analysis for the Global Burden of Disease Study 2017

Background: Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. Methods: The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. Findings: Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. Interpretation: This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing