pH Development Analysis of Alkaline and Low Salinity Water Flooding in sandstone cores

Master's thesis in Petroleum EngineeringLow salinity (LS) water flooding has been in the center of interest for conventional oil recovery in sandstone reservoir for more than two decades because of its low cost and potential for increased oil recovery. Though hundreds of researches have been done on LS EOR method, the mechanism behind the oil recovery is still debatable. Recently, Smart Water group of University of Stavanger has proposed a new chemical wettability alteration mechanism where protons (H+) from LS water replaces metal ions such as Ca2+, Na+ from the clay surface and made the surface more water wet by releasing polar organic oil components due to a pH increase. As a result, more oil is displaced towards production well and increases oil recovery. As the proton (H+) is adsorbed, pH of the produced water is increased and using this theory, Aksulu et. al. (2012) established a pH screening test as an experimental tool to check the LS potential for sandstone. pH of the system can also be increased by injecting alkaline water of high pH instead of creating in situ pH increase by LS water flooding. In this thesis, the transportability of alkalinity and development of pH was investigated for LS and alkaline water flooding. Three outcrop sandstone cores of different mineralogy were used for 12 pH screening tests at different temperatures. In addition with the pH screening test, pressure changes, density changes and ion chromatography tests were done during the flooding to observed the changes of produced water. pH-screening tests with alkaline water injection showed low potential for extra alkalinity compared with LS water injection. Almost two pH unit of injected high alkaline water is reduced by the minerals and formation water. On the other hand, the results of the pH-screening tests for LS water injection showed a potential for increasing the effluent LS water pH up to two units in comparison to its initial pH-value. Both the LS and alkaline water showed same trend of pH buildup though they had a big difference in bulk pH (almost 5 pH unit). Transportation of alkalinity through a mineral system with large surface area seemed to be challenging due to pH buffering from brine/mineral interactions as well as from chemical interactions involving inorganic cations from the formation water. It can be concluded after the thesis that an in-situ generation of alkaline conditions in the reservoir by injecting LS water seemed to have a larger potential for EOR purposes than transporting alkalinity by injecting high pH alkaline water through the reservoir

Outbreak of diarrheal diseases causes mortality in different geographical locations of Bangladesh during the 2021 COVID-19 era

ObjectivesDiarrhea is a major public health problem in low- and middle-income countries, including Bangladesh. Of the different spectrums of diarrheal diseases, cholera occurs every year, causing outbreaks and epidemics following a biannual seasonal pattern. Due to the COVID-19 pandemic, hospitalization for diarrheal diseases decreased in 2020 compared to the previous years. However, in 2021, massive outbreaks occurred in different geographical locations of the country. We described that an outbreak of diarrheal diseases causes mortality in different geographical locations in Bangladesh.MethodIn this study, we present a report of diarrhea outbreaks that were reported in 2018–2021 in different parts of Bangladesh, and data have been captured from different sources such as print and electronic media as well as from a nationwide surveillance system.ResultsAmong these locations, districts of Barisal Division, Kishorganj, Noakhali, Gopalganj, Bandarban, and Chattogram were the major hotspots of the outbreaks where high morbidity due to acute watery diarrhea and even mortality, which is usually low in Bangladesh, were recorded.ConclusionEarly detection and prevention and strengthening of the surveillance system are needed to combat the diarrheal upsurge, take immediate control, and adopt preventive strategies

Comparative Analysis among Different ZnO Nanoparticles Synthesized by Different Techniques

Semiconductor oxides were synthesized and systematically examined on 100 % cotton fabric to optimize the properties. Nano-technology is employed in this research work to form nanoparticles of semi-conductor oxides. Four samples were synthesized by using different methods and dyed to find the effective one. Different characterization techniques are used to characterize nanoparticles e.g. X-ray powder diffractometer, Energy dispersive X-ray spectroscope (EDS, EDX or EDXRF) and SEM images. By examining diffraction pattern and SEM images homogeneity, crystalline phase, transparent finishing process and unit cell dimensions are found. ZnO-3 (sample 3) (TEA 0.025M) treated cotton is revealed to have unique properties and implied a transparent finishing process

In-Vitro Study of Low Viscosity, and High Viscosity Direct Compression and conventional Grade Hypromellose for Modified Release Gliclazide tablets

Six different low to high viscosity hypromellose were used with lower soluble Gliclazide, alone to investigate the dissolution study and flow property. Dissolution behavior of formulated tablets was tested to identify the better efficacy. Dose dumping, pH dependency also was examined. Anti-diabetic Gliclazide tablets were prepared by direct compression method and the results of dissolution was found good in Methocel K100M DC for 73.25%. Tablets showed uniform weight, thickness, and lower percent ( 0.5%) friability. Result of Carrs index and Hausner ratio indicated good flow properties of powder granules. The percent release of the Gliclazide was analyzed by kinetic models. Release of the drug was higher using the higher viscosity grade. Gliclazide tablets were determined with the goodness of fit test of kinetic models. The release showed linearity in Higuchi Model with correlation coefficient value of R 2 = 0.973. In-vitro study demonstrated improved release profile using DC grade than CR grade alone

A Study on Life Cycle Analysis (LCA) of a Cotton Woven Shirt

The property of textile materials has gained a lot of attention thanks to the resource consumption and wastematerial emissions at the moment time. So, it's terribly essential and a core demand to gauge theenvironmental result of textiles from a life cycle perspective to develop the property of textiles.Environmental problems became vital over the previous few years owing to increasing pollution, wastematerials, heating, etc. shoppers have additionally begun to demand inexperienced products. As a result ofthese events, additional strategic and systematic approaches square measure necessary for ever-changingenvironmental problems. Life Cycle Analysis (LCA) is one of the tools to satisfy this necessity. During thisresearch, we have a tendency to square measure analyzing the LCA of a ‘Cotton woven Shirt’, andscientifically evaluating the environmental impacts also as resource utilization to supply, from raw materialsto the disposal of the merchandise at the top of life

Polysulphate: A New Enhanced Oil Recovery Additive to Maximize the Oil Recovery From Carbonate Reservoirs at High Temperature

Seawater (SW) injection is an enhanced oil recovery (EOR) success in the North Sea carbonate reservoirs due to wettability alteration toward a more water-wet state. This process is triggered by the difference in composition between injection and formation water (FW). “Smartwater” with optimized ionic composition can easily be made under laboratory conditions to improve oil recovery beyond that of SW. However, in the field, its preparation may require specific water treatment processes, e.g., desalination, nanofiltration, or addition of specific salts. In this work, a naturally occurring salt called Polysulphate (PS) is investigated as an additive to produce smartwater. Outcrop chalk from Stevns Klint (SK), consisting of 98% biogenic CaCO3, was used to investigate the potential and efficiency of the PS brines to alter wettability in chalk. The solubility of PS in SW and deionized water, and brine stability at high temperatures were measured. Energy dispersive X-ray and ion chromatography were used to determine the composition of the PS salt and EOR solutions, and to evaluate the sulphate adsorption on the chalk surface, a catalyst for the wettability alteration process. Spontaneous imbibition (SI), for evaluating wettability alteration of PS brines into mixed-wet chalk was performed at 90 and 110°C and compared against the recovery performance of FW and SW. The solubility tests showed that the salt was easily soluble in both deionized water and SW with less than 5% solid residue. The deionized PS brine contained sulphate and calcium ion concentrations of 31.5 and 15.2 mM, respectively, and total salinity was 4.9 g/L. This brine composition is very promising for triggering wettability alteration in chalk. The SW PS brine contained 29.6 mM calcium ions and 55.9 mM sulphate ions, and a total salinity of 38.1 g/L. Compared with ordinary SW, this brine has the potential for improved wettability alteration in chalk due to increased sulphate content. Ion chromatography revealed that the sulphate adsorbed when PS brines were flooded through the core, which is an indication that wettability alteration can take place during brine injection. The reactivity was also enhanced by increasing the temperature from 25 to 90°C. Finally, the oil recovery tests by SI showed that PS brines were capable of inducing wettability alteration, improving oil recovery beyond that obtained by FW imbibition. The difference in oil recovery between ordinary SW and SW PS imbibition was smaller due to the already favorable composition of SW. PS brines showed a significant potential for wettability alteration in carbonates and are validated as a potential EOR additive for easy and on-site preparation of smartwater brines for carbonate oil reservoirs. PS salt, added to the EOR solution, provides the essential ions for the wettability alteration process, but further optimization is needed to characterize the optimal mixing ratios, ion compositions, and temperature ranges at which EOR effects can be achieved.publishedVersio

Micronutrients and Anaemia

Micronutrient deficiencies and anaemia remain as major health concerns for children in Bangladesh. Among the micronutrient interventions, supplementation with vitamin A to children aged less than five years has been the most successful, especially after distribution of vitamin A was combined with National Immunization Days. Although salt sold in Bangladesh is intended to contain iodine, much of the salt does not contain iodine, and iodine deficiency continues to be common. Anaemia similarly is common among all population groups and has shown no sign of improvement even when iron-supplementation programmes have been attempted. It appears that many other causes contribute to anaemia in addition to iron deficiency. Zinc deficiency is a key micronutrient deficiency and is covered in a separate paper because of its importance among new child-health interventions

Prenatal early food and multiple micronutrient supplementation trial reduced infant mortality in Bangladesh, but did not influence morbidity.

AIM: A previous maternal and infant nutrition intervention in rural Matlab, Bangladesh, showed that prenatal nutrient supplements improved child survival, but had no effect on size at birth. This secondary analysis examined whether prenatal multiple micronutrient supplements (MMS), on their own or combined with an early invitation to receive prenatal food supplements, affected child morbidity. METHODS: This randomised trial enrolled 4436 pregnant women from November 2001 to October 2003 and allocated them to early or standard invitations to food supplements, in the ninth and 20th weeks of pregnancy, respectively, and supplements of either the standard 60 mg iron with 400 μg folic acid, 30 mg iron with 400 μg folic acid or MMS. Quasi-Poisson regression was used to analyse morbidity. RESULTS: There were 3560 single live births and 3516 had morbidity data. The incidence rates of fever, diarrhoea and acute lower respiratory tract infection were 15.3, 3.6 and 2.3 episodes per person-year, respectively. The separate or combined interventions had no effect on morbidity up to 24 months. CONCLUSION: Early invitations to prenatal food supplements or prenatal MMS had no effect on common infections in rural Bangladesh, suggesting that earlier findings on improved child survival were not mediated by an effect on child morbidity

Effect of a randomised exclusive breastfeeding counselling intervention nested into the MINIMat prenatal nutrition trial in Bangladesh.

AIM: It is unknown whether maternal malnutrition reduces the effect of counselling on exclusive breastfeeding. This study evaluated the effect of breastfeeding counselling on the duration of exclusive breastfeeding, and whether the timing of prenatal food and different micronutrient supplements further prolonged this duration. METHODS: Pregnant women in Matlab, Bangladesh, were randomised to receive daily food supplements of 600 kcal at nine weeks of gestation or at the standard 20 weeks. They also were allocated to either 30 mg of iron and 400 μg folic acid, or the standard programme 60 mg of iron and folic acid or multiple micronutrients. At 30 weeks of gestation, 3188 women were randomised to receive either eight breastfeeding counselling sessions or the usual health messages. RESULTS: The median duration of exclusive breastfeeding was 135 days in the counselling group and 75 days in the usual health message group (p < 0.001). Prenatal supplements did not modify the effects of counselling. Women in the usual health message group who were randomised to multiple micronutrients exclusively breastfed for 12 days longer than mothers receiving the standard iron-folate combination (p = 0.003). CONCLUSION: Breastfeeding counselling increased the duration of exclusive breastfeeding by 60 days. This duration was not influenced by the supplements