Water Sink Research Articles

Reducing freshwater consumption in pulp and paper industries using pinch analysis and mathematical optimization

The pulp and paper (P&P) industries are classified among the water-intensitive industries. In this work, implementation of the Water Closed-Loop System (WCLS) in a P&P factory to reduce water consumption and wastewater generation was reported. First, the water and steam network of the mill was synthesized, and water sinks and sources along with their flowrates were identified. The key pollutants, including chemical oxygen demand (COD), total suspended solids (TSS), and total dissolved solids (TDS), were pinpointed and acceptable levels for water sinks were acquired. In the second step, by using water pinch analysis with the direct-reuse approach, each limiting pollutant was investigated, and the maximum reduction in freshwater consumption equal to 36.9 % was obtained by considering TSS as the only pollutant. The minimum potential for reducing water consumption belonged to COD (4.0 %) and TDS (18.9 %). In the regeneration-reuse approach, the incomplete performance of the mill's treatment plant in removing COD and TDS resulted in no improvement in the results of the previous step. In the case of TSS alone, the reduction in freshwater consumption increased to 93.3 %. Mathematical optimization was used to study all limiting contaminants simultaneously. The direct-reuse approach achieved a 4.0 % reduction in water consumption, while the regeneration-reuse did not change water consumption compared to the direct-reuse approach, emphasizing the incomplete operation of the treatment plant. Finally, the output contaminants levels of a hypothetical decentralized and modified existing treatment plant were estimated using literature. In this case, the freshwater consumption of the mill declined by 93 %.

Community structure and network interaction of aerobic methane-oxidizing bacteria in Chongqing’s central urban area in the Three Gorges Reservoir, China

A reservoir is an important source of methane (CH4), which is consumed by aerobic methane-oxidizing bacteria (MOB), representing the main CH4 sink in water. The central urban area of Chongqing in the Three Gorges Reservoir (TGR) area was selected as the study area in 2021. High-throughput sequencing was used to analyze the community structure and abundance of MOBs. The results showed that Methylocystis (Type II) was the dominant MOB in water, whereas Methylococcus (Type I) and Methylocystis co-dominated the sediments. High water temperature in the study area largely accounted for the predominance of Type II MOBs in the two habitats. Moreover, the influence of environmental factors on MOB community and its interspecific relationship were significantly regulated by the operation of the TGR. In the low-water-level period, NO2--N and CO2 concentration significantly correlated with Methylocystis, whereas in the high-water-level period, the higher discharge and velocity weakened the influence of all environmental factors on Methylocystis. In addition, the scouring of sediments by increasing discharge in the high-water-level period caused a significant decrease in dissolved CH4 concentration. The decrease in substrate increased interspecific competition within the MOB community, especially between different types of MOBs, in the high-water-level period.

Risk evaluation of CO2 leakage through fracture zone in geological storage reservoir

CO2 storage in saline aquifers is an effective way to reduce the emission of CO2 into the atmosphere. The potential leakage problems are the main challenge for CO2 storage projects. However, the quantitative evaluation and analysis of the driving forces for the potential CO2 leakage problems are still lacking. In this paper, a stratified model embedded with a highly-permeable fracture zone was constructed to simulate CO2 leakage in the post-injection period. The acting forces and dimensionless numbers were systematically analyzed, and four stages were defined based on the leakage characteristics. Ultimately, a novel regression model was developed to predict the percentage of secure storage for CO2 at any dimensionless numbers. Results showed four distinct CO2 leakage stages: fast CO2 leakage stage (T1); decreasing CO2 leakage stage (T2); fast water sink stage (T3); and stable countercurrent flow stage (T4). Viscous force, gravity force, and capillary force were the dominant driving forces in turn in the first three stages. A stable countercurrent flow and CO2 leakage were maintained in the last period. In addition, the turning point of the flow pattern was delayed, and Gravity number (Gr) and Bond number (Bo) decreased obviously with the increase of initial pressure gradient. More importantly, most of the leaked CO2 was trapped in riskier forms (i.e. structural and residual trapping), and heavy acidification occurred in the shallow aquifer. The novel regression model showed that the percentage of secure storage could be enhanced by increasing Gr and/or decreasing the Ca. It is suggested that the pressure gradient at the end of injection should be optimized to store more CO2 and decrease the leakage risk simultaneously.

Methodology and application of precipitation isoscapes of stable hydrogen and oxygen isotopes

The precipitation isoscapes of stable hydrogen and oxygen isotopes combine isotope tracing technology with spatial perspective, which are useful to examine the source and sink of water in different regions, to understand the isotope fractionation in atmospheric, hydrological and ecological processes, and to reveal the pattern, process, and regime of water cycle on the earth's surface. We reviewed the development of database and methodo-logy for precipitation isoscape mapping, summarized the application fields of precipitation isoscape, and put forward the key research directions in the future. At present, the main methods in mapping precipitation isoscapes include spatial interpolation, dynamic simulation, and artificial intelligence. In particular, the first two methods have been widely used. The applications of precipitation isoscapes can be classified into four fields including atmospheric water cycle, watershed hydrological process, animal and plant traceability, and water resources management. The future works should focus on the compilation of observed isotope data as well as the data evaluation of spatiotemporal representativeness, and pay more attention to develop the long-term products and quantitatively assess the spatial connection among various water types.

Water productivity, sink production and varietal differences in panicle structure of rice (Oryza sativa L.) under drip irrigation with plastic-film mulch

Water productivity, sink production and varietal differences in panicle structure of rice (Oryza sativa L.) under drip irrigation with plastic-film mulch

THE DYNAMICS OF MAN'S HISTORY AND ECONOMIC DEVELOPMENT: A REFOCUS ON ECOLOGICAL DISTURBANCE AND CLIMATE CHANGE

Man’s history and developmental endeavour have been advancing alongside a trail of ecological ramifications and climate change. Since prehistoric times, scientists have not recorded an accelerated shift in ecology during any other epoch beside that of modern man on the planet. The paper seeks to explore how man’s history and development affects ecology and climate. It uses desk analysis to recollect data from global assessment reports and runs a One paired Sample Means t-Test, 1 tailed, 8 df, at Pearson Correlation value 0.458 and 0.5  level. Findings show that, there is global climate change, seen in global warming trends; and imbalance in ecological footprint, seen in depletion of air, water and land sinks. The t-Testreveals significant net loss of global forest cover. The study also, found that at present,processes of development generally tend to damage ecology. Therefore, the study recommends a refocus to sustainable means of development.

Soil and water conservation measures to adapt cropping systems to climate change facilitated water stresses in Africa

Complex controls and non-linear responses of the climate system to global warming make it difficult to have clear-cut predictions of future precipitation amounts and timelines. It is, however, evident from current observations that some predictions of unusually high rates of flooding and droughts are occurring and threatening food security in sub-Saharan Africa (SSA). The impact of climate change is immense on SSA though it contributes the least to climate change globally. Crops face lots of growth challenges which reduce their productivity under drought and flood conditions. SSA must prepare agricultural soils for the anticipated climate variabilities, to ensure sustainable food availability. The effort to adapt soils to climate change must be a concerted one, using technologies from various facets of science. Stakeholders must adopt water-smart strategies that maintain proper soil-water balance. They should focus on manageable inherent soil properties that control the susceptibility/adaptability of cropping systems to climate change. Conservation agriculture techniques that target improving soil organic matter and maintaining soil life; protecting the soil from compaction and erosion; reducing soil disturbance; enhancing soil infiltration and groundwater recharge capacity, must be applied to our soils. A number of these techniques equip the soils to be better sinks of excess water in flood-prone areas and improve water-holding capacities in drought-prone ones. Governments, farmers, and all stakeholders must also invest in both simple and complex water harvesting/ re-directing infrastructure which conserve water for future use. Water-efficient irrigation systems must be employed by farmers during water scarcity. Most importantly, gaps between research, industry, farmers, and governments must be bridged to for easy flow of information on improved technologies and quick adoption of climate change mitigation strategies.

Water Security Experiences and Water Intake Among Elementary Students at Low-Income Schools: A Cross-Sectional Study.

To examine students' experiences of water security at school and how experiences relate to intake of water from different sources of water at school. In this cross-sectional study, 651 students in grades 3 to 5 in 12 low-income public elementary schools in the San Francisco area completed surveys about their daily intake of water from different sources of water at school, experiences of water security including safety, cleanliness, and taste of water at school, and their demographics. Multivariable linear regressions examined associations between students' water security experiences at school and reported intake from different sources of water at school. Approximately half of students were Latino (56.1%) and had overweight/obesity (50.4%). Most (74.5%) had some negative water security experience at school. Students drank from the school fountain or water bottle filling station a mean of 1.2 times/day (standard deviation [SD]=1.4), sinks 0.2 times/day (SD=0.7), tap water dispensers 0.2 times/day (SD=0.6), and bottled water 0.5 times/day (SD=1.0). In multivariable linear regression, students with more negative experiences of school water security drank less frequently from fountains (-0.5 times/day, P value < .001), but more frequently from tap water dispensers (0.1 times/day, P value = .040) and sinks (0.1 times/day, P value = .043), compared to students with no negative perceptions. On average, students had negative school water security experiences, which decreased their consumption of water from tap water sources. However, relationships between negative water security experiences and reported water intake appeared to be mitigated by water source. Schools should consider installing more appealing water sources to promote water intake.

Developing Realistic Models for Assessing Marine Plastic Pollution in Semi-Enclosed Seas

Having steadily increased with global production in the past 50 years, the presence and accumulation of plastic debris is now recognized as a major environmental problem, with consequences directly affecting not only marine ecosystems, but also society and human well-being. After human activities release plastic litter, it is either directly discharged into the ocean or it is transported to the sea via inland pathways (e.g., rivers, lakes, wastewater treatment plants). Once in the ocean, plastics are further transported and transformed by processes such as ocean currents, winds and waves, water dispersion, fragmentation, biofouling, sinking, sedimentation, and beaching (Figure 1).

Study on Water Sinking Sand Method for Sand Backfilling

Based on the partial culvert backfilling project of the JI-HEI Expressway construction in Heilongjiang Province, China, this study investigates the impact of the physical and mechanical characteristics of backfill sand on the compaction degree of sand backfilled using the water sinking sand method. The research includes on-site sampling of the backfill sand, indoor geotechnical testing, water sinking sand method backfilling, and compaction degree testing of the backfilled material. The study explores the particle size distribution, moisture content, density, compaction characteristics, California Bearing Ratio (CBR), rebound modulus, and other physical and mechanical attributes of the sand. It also delves into the water sinking sand method backfilling process and the compaction degree of the soil layer after backfilling. The findings indicate that the backfill sand in this project is a loose, medium to coarse sand with a low moisture content. Its maximum dry density is approximately 1.92 g/cm³, and the optimal moisture content is around 8%. When the sand reaches maximum dry density, both CBR value and rebound modulus reach their highest levels. The reduction in rebound modulus of the sand is not significant, suggesting good water stability. The actual compaction degree of the soil layer achieved through water sinking sand method backfilling ranges from 96% to 99%, meeting the compaction requirements of conventional engineering practices. The application of the water sinking sand method for sand backfilling is characterized by its simplicity, high construction efficiency, and quality assurance, making it suitable for widespread adoption in future engineering projects.

MICROPLASTIC IN INDIA A SHODDY AFFAIR

Small sized fragmented plastic or microplastic contamination is widespread and considered as one of the major problems of aquatic environment. Ability to resist bio-degradation amplifies longevity, long transportation and aggregation, enables microplastics to find their sink in the drinking water. The situation in India is more critical as sources of microplastics are far too many and the high sediment flux in the rivers may easily facilitate the process of fragmentation during typical tropical climate, making the aquatic ecosystem of India extremely vulnerable. Detailed research and careful monitoring activities could bring clearer picture of the scenario and assess the impact of plastics on environment and biota. Some mechanism through which the emissions at the source could be checked or some other ways to reduce and reuse plastic waste or some new novel business solutions are essential to tackle this problem.

Temperature dependence of dielectric properties of blood at 10 Hz-100 MHz.

The temperature dependence of the dielectric properties of blood is important for studying the biological effects of electromagnetic fields, electromagnetic protection, disease diagnosis, and treatment. However, owing to the limitations of measurement methods, there are still some uncertainties regarding the temperature characteristics of the dielectric properties of blood at low and medium frequencies. In this study, we designed a composite impedance measurement box with high heat transfer efficiency that allowed for a four/two-electrode measurement method. Four-electrode measurements were carried out at 10 Hz-1 MHz to overcome the influence of electrode polarization, and two-electrode measurements were carried out at 100 Hz-100MHz to avoid the influence of distribution parameters, and the data was integrated to achieve dielectric measurements at 10 Hz-100MHz. At the same time, the temperature of fresh blood from rabbits was controlled at 17-39°C in combination with a temperature-controlled water sink. The results showed that the temperature coefficient for the real part of the resistivity of blood remained constant from 10Hz to 100kHz (-2.42%/°C) and then gradually decreased to -0.26%/°C. The temperature coefficient of the imaginary part was positive and bimodal from 6.31kHz to 100MHz, with peaks of 5.22%/°C and 4.14%/°C at 126kHz and 39.8 MHz, respectively. Finally, a third-order function model was developed to describe the dielectric spectra at these temperatures, in which the resistivity parameter in each dispersion zone decreased linearly with temperature and each characteristic frequency increased linearly with temperature. The model could estimate the dielectric properties at any frequency and temperature in this range, and the maximum error was less than 1.39%, thus laying the foundation for subsequent studies.

Investigation the Origins of Groundwater Salinity in Baghdad City by Using Environmental Isotopes and Hydrochemical Techniques

The hydrochemical and isotopic techniques have become one of the most popular and successful methods for determining the hydrogeochemical features of groundwater in recent years. A total of 15 samples were collected during wet (March, 2021) and dry (August, 2021) seasons. An approach with major elements (Cl-, Na+, Mg2+, Ca2+, and SO4 2=) and multi-isotope (2H, 18O) are used in this study to solve the geochemical variation of salinity in groundwater in Baghdad. The results of the analysis of groundwater samples in the study area showed that the major cations were Ca2+ and Na+, while the major anion was SO4, Cl, and HCO3. The Ca-SO4 and Ca-Na-Cl-SO4. hydrochemical facies are the dominant hydrochemical facies of groundwater on the Al-Karakh and Al-Russafa sides, respectively. Ca-HCO3 was found to be the dominant hydrochemical facies of the Tigris River. Human activities and geochemical processes may have caused differences in hydrochemical Facies. According to isotope analysis, the study area has multiple sources of salinity. This can be attributed to the effects of natural dissolution of the salt compounds, mixing with sewage, and industrial water sink. The results and data from this work can be used to research groundwater recharge and interaction, as well as to protect groundwater quality.

Water-based triboelectric nanogenerator for wireless energy transmission and self-powered communication via a solid-liquid-solid interaction

Wireless communication has affected all aspects of our lives. However, most wireless communication devices require an external power supply, which undoubtedly hinders the development of numerous sensors. Triboelectric nanogenerator (TENG), a self-powered technology, has become an even more attractive solution to the energy problem of sensors. Herein, a novel solid-liquid-solid TENG configuration consisting of a polytetrafluoroethylene (PTFE) sheet, a water sink, and a graphite electrode is proposed. It is worth noting that it can transmit mechanical energy by employing only the electric double layer (EDL) formed at the interface between water and the graphite electrode. PTFE induces mechanical energy generated by motion to be extracted as electrical energy at the remote end, which provides the basis for wireless energy and information transmission. More impressively, a self-powered application based on the designed TENG was successfully demonstrated to transmit Morse code messages through the water as a medium. This approach frees the constraints of cables and produces intuitive signals that are easy to translate. This study paves the way for a promising strategy in the development of wireless energy transmission and battery-less communication.

The epidermal bladder cell-free mutant of the salt-tolerant quinoa challenges our understanding of halophyte crop salinity tolerance.

Halophytes tolerate high salinity levels that would kill conventional crops. Understanding salt tolerance mechanisms will provide clues for breeding salt-tolerant plants. Many halophytes, such as quinoa (Chenopodium quinoa), are covered by a layer of epidermal bladder cells (EBCs) that are thought to mediate salt tolerance by serving as salt dumps. We isolated an epidermal bladder cell-free (ebcf) quinoa mutant that completely lacked EBCs and was mutated in REBC and REBC-like1. This mutant showed no loss of salt stress tolerance. When wild-type quinoa plants were exposed to saline soil, EBCs accumulated potassium (K+ ) as the major cation, in quantities far exceeding those of sodium (Na+ ). Emerging leaves densely packed with EBCs had the lowest Na+ content, whereas old leaves with deflated EBCs served as Na+ sinks. When the leaves expanded, K+ was recycled from EBCs, resulting in turgor loss that led to a progressive deflation of EBCs. Our findings suggest that EBCs in young leaves serve as a K+ -powered hydrodynamic system that functions as a water sink for solute storage. Sodium ions accumulate within old leaves that subsequently wilt and are shed. This mechanism improves the survival of quinoa under high salinity conditions.

ПАДЕНИЕ ПЯТЕН СОЛЕНОЙ ВОДЫ НА НАКЛОННОЕ ДНО В ОКРУЖЕНИИ ПРЕСНОЙ: ДИНАМИКА И СТРУКТУРНЫЕ ОСОБЕННОСТИ РАСПРОСТРАНЕНИЯ ПЛОТНОСТНОГО ФРОНТА ВВЕРХ ПО СКЛОНУ

The study of the dynamics of two small volumes of water with negative buoyancy (patches of salt water), imitated a sinking of dense water into an underlying water, was carried out. These volumes usually appear in the process of surface water cooling during seasonal convection in the coastal zone of the sea. The main tools of investigation were laboratory and numerical experiments. The main stages of motion of patches were identified: sinking, contact, and spreading along a bottom slope. The process of interaction of the water patches during their movement up the bottom slope was detailed in laboratory experiments. Patches of salt water retained unmixed long time, that confirm the laminar character of the appearing flows. Distributions of tracers obtained in the calculations was analyzed with the aim to identify the characteristic stages of the flow of patches up the slope. Three stages were suggested: initial contact, diving, wrapping and breaking. For the first time dense water flow up the slope, which occur as a result of sinking of small volumes of salt water, was described. The results allow us to notice the intensification of mixing of water dense than underlying waters in the process of surface water cooling in coastal zone of the sea.

Disjunctive programming model for the synthesis of property-based water supply network with multiple resources

Industrial water supply networks can use multiple water resources (i.e., municipal water, surface water, municipal treated wastewater, groundwater, and seawater) with their respective pre-treatment technologies to meet the industrial water demand. The water quality of each water resource varies, and the associated pre-treatment technologies provide different technical and economic efficiencies that directly impact the overall cost of the water supply network. This paper proposed a superstructure-based mathematical modeling optimization to design the multi-resources industrial water supply network with optimal pre-treatment technologies. The established model includes the relative equations among different pre-treatment units and water sinks, flow rate constraints, property constraints, logic constraints, and cost constraints. These constraints are used to describe water treatment technologies selection through general disjunctive programming (GDP) and transform them into a mixed-integer nonlinear programming (MINLP) model for the problem solution. The minimum annualized cost of the water supply network is taken as an objective function. The optimization and comparison analysis of the coastal oil refinery water supply system is illustrated. The results show that an integrated water supply network of surface water and municipal treated wastewater has the lowest annualized cost of 12.3 million CNY/y. The cost is reduced by 7.44 million CNY/y compared to municipal water as the single water resource. This integrated water supply network saves freshwater resources, provides substantial economic gains, and encourages municipal treated wastewater reuse.

Cabbeling due to mixing of the Bering Strait and the Chukchi Sea waters on seasonal and climatic scale

Cabbeling due to mixing of the surface waters from the Bering Strait and the Chukchi Sea is evaluated quantitatively and variations of its impact on seasonal and climatic scale are analyzed. The cabbeling effect increases additionally the mixed water density in 0.059 kg/m3 in summer and in 0.001 kg/m3 in winter. Seasonal variation of the cabelling repeats the seasonal variation of temperature difference between the interacted water masses (ΔT ~ 5,0 оC in summer, ΔT ~ 0,5 оC in winter). This process provides additional energy for sinking of warm and salt mixed water in summer, when it penetrates far into the Arctic. In winter, the temperature difference between the mixing waters is about zero, so the cabbeling almost disappears. Both temperature and salinity have climatic trends in the Chukchi Sea that causes the climate-scale variation of the cabbeling: its impact increases in 0.002 kg/m3 per decade in summer because of climatic heating (~0,13 оC/decade) and salinity decrease (~0.04 psu/decade).

Recent Climatic Change Research in the Chukchi and Beaufort Seas Based on Numerical Simulation

This study analyses climatic changes in the Chukchi Sea and the Beaufort Sea based on numerical modeling using a regional ice-ocean model. Numerical experiments were carried out for the period 2000–2019. NCEP/NCAR reanalysis data were used to determine the ocean and sea ice surface fluxes. The temperature, salinity, and transport of Pacific waters entering the Arctic Ocean were specified as boundary conditions in the Bering Strait. Three types of boundary values were used for the experiments: a) monthly average climate data averaged over the period 1990–2003; b) monthly average climate data averaged over the period 2003–2015; c) average monthly measurement data since 2016 to 2019. The sensitivity of the model to the variability of the transport and temperature of the incoming Pacific waters was studied, and the effect on the ocean heat content, the volume and sea ice extent was analyzed.Numerical experiments simulate the transport of warm Pacific water across the Chukchi shelf in the north direction and onto the Beaufort Sea shelf, the process of warm water sinking on the continental slope in the autumn-winter period. In recent years, at the points on the boundary of the shelf and deep-water areas, the amplitude of seasonal temperature fluctuations in the surfacelayer increases and the temperature rises significantly at a depth of 100 m.The simulation results demonstrate an increase in the ocean heat content and decrease in the ice volume in the Beaufort and Chukchi Seas, caused by an increase in atmospheric temperature. We also showed that the increase in temperature and transport of the Pacific water, which began after 2003, contributed to an additional increase in the ocean heat content of both seas, a reduction in the ice cover area, and a delay in the ice formation in the Chukchi Sea.

Investigating an Increased Incidence of Burkholderia Cepacia Among Non-Cystic Fibrosis Pediatric Patients

<h3>Background</h3> Burkholderia cepacia Complex (BCC), commonly identified in patients with Cystic Fibrosis (CF), has been associated with outbreaks from contaminated medications (Abdelfattah 2018) and devices (Lucero, 2011). An increase of BCC in cultures of non-CF patients prompted an investigation including an assessment of commonalities such as medications, procedures, staffing, equipment, and treatment locations. Our journey to identify a source and implement control measures led to a yearlong, multi-facility outbreak investigation with support and involvement of the Massachusetts Department of Public Health and the Centers for Disease Control. <h3>Methods</h3> Literature review of past outbreaks aided in narrowing our scope of potential sources. Chart reviews helped identify commonalities across patients, however, these commonalities did not elucidate a root cause. Through the Burkholderia cepacia Research Laboratory & Repository at the University of Michigan, whole-genome sequencing identified matching isolates. Over 20 patients and 50 environmental isolates from our facility were evaluated. <h3>Results</h3> Three distinct BCC clusters were identified: a larger cluster of 10 patients with Burkholderia cenocepacia recA subgroup and two smaller clusters of 2 patients each with a matching Burkholderia cepacia indeterminate species. Despite environmental sampling not identifying a source, our Respiratory program re-educated staff on not storing respiratory equipment within the splash zone of a sink and use of sterile water for all respiratory care items. Additionally, a policy was formalized for reprocessing of custom tracheostomies, and we transitioned to single-use temperature probes for one of our ventilators. Ultimately, new information suggested the primary source was external to our facility. <h3>Conclusions</h3> Early identification of outbreaks in healthcare facilities and evaluation of all possible causes is central to Infection Prevention. Ongoing surveillance and analysis utilizing established epidemiologic methods are essential to successfully minimizing the adverse effects to patients.