Water Consumption Rate Research Articles

Konsumsi dan Kebutuhan Air Selada Pada Teknik Hidroponik Sistem Terapung

Teknik Hidroponik Sistem Terapung (THST) adalah teknik hidroponik yang media tanamnya ditempatkan pada styrofoam yang mengapung di kolam besar yang mengandung larutan nutrisi. Kendala umum yang dihadapi oleh teknik hidroponik ini adalah tidak adanya tambahan air selama musim tanam, sehingga tingkat air di kolam menyusut akibat konsumsi air oleh tanaman. Penelitian ini bertujuan untuk mengetahui tingkat konsumsi air yang berfluktuasi selama masa tanam dan penambahan air yang diperlukan untuk menjaga tingkat muka air. Rata-rata konsumsi air pada penelitian ini adalah 0,74 mm/hari. Akumulasi konsumsi air selama 54 hari dalam dua periode musim tanam adalah 40 mm. Tingkat konsumsi air pada awal musim tanam lebih kecil yaitu sebesar 0,75 mm/hari dan terbesar terjadi pada akhir musim tanam sebesar 2,09 mm/hari. Akhirnya, kebutuhan air untuk menjaga kadar air pada awalnya adalah 0,76 liter/hari/m2 dan kemudian meningkat sampai mencapai 2,09 liter/hari/m2 pada akhir musim tanam atau setara dengan 7,59 m3 per 90 m2 luasan tanam.

Using hair and fingernails in binary logistic regression for bio-monitoring of heavy metals/metalloid in groundwater in intensively agricultural areas, Thailand

In this study, the hair and fingernails of the local people in an intensively cultivated agricultural area in Ubon Ratchathani province, Thailand, were used as biomarkers of exposure to arsenic (As) and heavy metals. The study area has shallow acidic groundwater that is contaminated with As and heavy metals. The local people often consume this shallow groundwater; thus, they are exposed to As and heavy metals. Hair and fingernail samples were collected to characterize the differences between shallow groundwater drinking (SGWD) and tap water drinking (TWD) residents. The concentrations of As and the heavy metals Cd, Pb and Hg were significantly higher in the hair samples from the SGWD group than those from the TWD group, especially for As (0.020–0.571 vs. 0.024–0.359µg/g) and Cd (0.009–0.575 vs. 0.013–0.230µg/g). Similarly, the concentrations of As and the heavy metals in the fingernail samples collected from the SGWD group were larger than those of the TWD group, especially for As (0.039–2.440µg/g vs. 0.049–0.806µg/g). The χ2 statistic and binary logistic regression were used to find the associated factors and assess the associated probabilities. The regression results show that the factors associated with the concentrations of As and the heavy metals in the hair samples were drinking water source, rate of water consumption, gender, bathing water source, education, smoking and underlying disease, whereas the factors associated with the concentrations of these species in the fingernail samples were drinking water source, gender, occupation, work hours per day, alcohol consumption, and the use of pesticides.

Estimation of underground water radon danger in Bakreswar and Tantloi Geothermal Region, India

The main aim of the study is to present an evaluation of radon concentration in underground water of Bakreswar and Tantloi geothermal region which is mainly used for drinking purposes of the local people. Water samples were collected from tube-wells at 173 different locations. The radon (222Rn) concentration level was observed to fluctuate widely between 3.3 and 803.8 Bq/l with an average of 106.8 Bq/l. Nearly 42% of the samples had radon concentration above the safe limit of 100 Bq/l recommended by World Health Organisation (WHO) and European Union Commission (EU). Considering the WHO and International Commission on Radiological Protection recommended water consumption rate for adults (730 l/year) the corresponding total annual effective dose of the samples were estimated to assess the probable health risk. Total annual effective dose of the samples were varied between 16.72 and 4079.47 µSv/year with an average value of 541.92 µSv/year. About 95% samples exceed the WHO and EU Commission proposed safe limit of 100 µSv/year.

A three-phase solid-liquid-gas slug flow mechanistic model coupling hydrate dispersion formation with heat and mass transfer

Pipe blockage due to gas hydrate formation is a main concern in the oil and gas industry due to the revenue losses caused by either production impairments or interruptions, and to the high costs associated to the elimination of such blockages. Assuming a hydrate formation rate in the gas-water interface based on the system subcooling, the present work models the transition from two-phase liquid-gas to three-phase solid-liquid-gas flows when hydrates form. The multiphase flow is assumed to be within the slug flow pattern region, as this is the prevailing flow regime in offshore production scenarios. The model couples mass, momentum and energy balances for the slug flow unit cell. The hydrate phase is assumed as homogeneously dispersed in the water. The gas and water consumption rates due to hydrate formation are modeled as source terms in the mass balance equations. The exothermic characteristic of the hydrate formation is taken into account in the energy conservation equation. The model provides analytic expressions for temperature and pressure distributions along the pipeline. However, the unit cell geometry is solved by numerical integration and the model closure is achieved only when empirical correlations for the slug frequency, the unit cell translational velocity and the slug aeration are used. The results from the numerical simulations are presented for the same input parameters for cases with and without hydrate formation. The discussion focuses on the influence of hydrate formation in the slug flow hydrodynamics and heat transfer. The main mechanisms affecting the mixture temperature and pressure distributions, the mixture heat transfer coefficient, the superficial velocities of the phases, the liquid loading, the slug flow frequency and the unit cell geometry are presented.

Radiochemical separation and determination of radium-228 in bottled mineral waters by low level gamma spectrometry and its committed effective dose

​The gross beta and 228Ra radioactivity measurements in mineral waters were performed by proportional counter and gamma spectrometry, respectively, in this study. The natural mineral water samples were collected from various regions of Turkey for this study. Gross beta activities have been determined according to the United States Environmental Protection Agency standard method (EPA 900). In the case that the gross beta activity was determined to be greater than 1 Bq/L, then the 228Ra activity concentration in the related mineral water sample was specifically measured. 228Ra activity in mineral water samples was determined by high-purity germanium (HPGe) detector. The photopeak efficiencies were calculated by modeling the sample geometry and the detector in Canberra software LabSOCS. The gross beta activities in the eight of 32 bottled mineral water samples were greater than 1 Bq/L. 228Ra activity concentrations in bottled mineral waters were determined within 0.100–1.04 Bq/L. The committed effective doses were calculated for three different scenarios according to mineral water consumption rates.

حل تعارضات برای مدیریت پایدار منابع آب بر اساس تئوری بازی؛ مطالعه موردی

About 90 percent of water consumption is allocated to the agricultural sector in Iran. Obviously, the amount of agricultural benefit depends on the amount of water resource using. The farmer imagines that increasing the amount of cultivated area and irrigation will also increase amount of the crop and consequently his benefit. The assumptions of farmers lead to the destruction of the environment which finally will result in the tragedy of common pool resources. Preventing water resource overdraft in order to support sustainable development as the environmental object and maximizing the farmers' net benefits as the economic object, are in conflict in the short-term. It is necessary to find a balance between them. For this purpose, the optimum consumption of a water resource and farmers' net benefits are determined for the Urmia study region during the 2014-2015 crop year. This is done by using conflict resolution methods including a non-symmetric Nash, non-symmetric Kalai-Smorodinsky, non-symmetric area monotonic and non-symmetric equal loss solution in four crop pattern scenarios. The results revealed that increasing environmental weight decreases cultivated area and consequently agricultural net benefit in all crop scenarios. The fourth scenario is more reasonable and admissible due to its feasibility and acceptability by farmers. Also a comparison of the fourth scenario with the current situation in equal weights of environmental and economic objects and by assuming cultivation of major crops in the region showed that in this scenario the water consumption rate reduces 17% and the net benefit of farmers increases 10%.

Segmenting a Water Use Market

Water scarcity due to climate change, low rainfall, and the damaging effects of human activity is a global concern. In the United Arab Emirates, water consumption rates are among the highest in the world. Recently, researchers have suggested social marketing might assist to change individual water consumption. Guided by the theory of interpersonal behavior (TIB), this study sought to identify segments in one water use market, drawing on demographic, geographic, psychographic, and behavioral segmentation bases. A cross-sectional theoretically based online survey was designed based on the TIB constructs to collect data about one residential population’s water knowledge/awareness attitudes, emotions, religiosity, habits, surrounding social norms, and facilitating factors. E-mail invitations to complete the survey were sent to the target population. Two-step cluster analysis was used to analyze the data ( N = 1350), and three major water user segments were identified (regular, conscious, and careless users), who could be characterized based on psychographic and water use (behavioral) determinants. Audience segmentation is often absent or done on the fly, and this article proposes that effectiveness could be improved by applying a rigorous and theoretically based approach. Opportunities for social marketers to develop interventions targeting specific user groups are subsequently identified, along with a future research agenda.

The environmental impacts of green technologies in TX

Using detailed electricity consumption and solar generation data from homes in an Austin TX neighborhood between 2013 and 2015, we calculate the environmental benefits of electric vehicles and rooftop solar panels. We estimate time-varying electric grid marginal emissions and water consumption rates in ERCOT through a regression based analysis, and find that emissions and water consumption rates are lowest at high demand times due to those hours' reliance on cleaner natural gas generators. We utilize these emissions and water consumption rates to estimate the avoided GHGs and water consumption from grid electricity that solar panels provide. For electric vehicles, we estimate the net effect of this technology, given the avoided gasoline consumption but increase in grid-related charging. We find that, on average, solar panels avoid approximately 75% of yearly grid-related emissions (0.7tons CO2/year per kW of solar capacity) and yearly grid-related water consumption (400gal/year per kW of solar capacity), where the benefits depend on the orientation of the panels. We also find that electric vehicle deployment results in avoiding up to 70% of fuel-related emissions (3.5tons CO2/year) and 60% of fuel-related water consumption (1400gal/year), though the benefits significantly decrease with the efficiency of the counterfactual vehicle.

A systems dynamic model of a coal-based city with multiple adaptive scenarios: A case study of Ordos, China

Cities based on coal resources have increasingly important social and economic roles in China. Their strategies for sustainable development, however, urgently need to be improved, which represents a huge challenge. Most observers believe that the continued progress of these cities relies on the optimization of scientific adaptive management in which social, economic, and ecological factors are incorporated. A systems perspective that combines policies, management priorities, and long-term policy impacts needs to be applied. To date, however, such an approach has not been adopted, which means it is difficult to implement adaptive management at the regional scale. In this study, we used various situations to develop a multiple adaptive scenario system dynamics model. We then simulated a range of policy scenarios, with Ordos in the Inner Mongolia Autonomous Region as a case study. Simulation results showed that the current strategy is not sustainable and predicted that the system would exceed the environmental capacity, with risks of resource exhaustion and urban decline in 2025–2035. Five critical policy variables, including the urban population carrying capacity, rates of water consumption and water recycling, and expansion of urban land cover, were identified during sensitivity analysis. We developed and compared six socio-economic scenarios. The urban area, represented by the urban population density, seemed to transition through five different stages, namely natural growth, rapid growth, stable oscillation, fading, and rebalancing. Our scenarios suggested that different policies had different roles through each stage. The water use efficiency management policy had a comprehensive far-reaching influence on the system behavior; land urbanization management functions dominated at the start, and population capacity management was a major control in the mid-term. Our results showed that the water recycling policy and the urban population carrying capacity were extremely important, and both should be reinforced and evaluated by the local governments.

The water consequences of a transitioning US power sector

The US power sector is in a state of transition, prompted by significant shifts in technological innovations, energy markets, regulatory structures, and social pressures. As the electricity generation fleet changes, so too does the spatial & temporal distribution of the cooling water requirements for power plants. However, to date, these impacts have yet to be quantified. This study uses power plant-specific fuel consumption, generation, and cooling water use data to assess changes in the water withdrawn and consumed by thermoelectric power plants across 8-digit Hydrologic Unit Code (HUC-8) watersheds between 2008 and 2014. During this period, a few prominent trends are noted, including transitions in generation from coal-fired steam to natural-gas combined cycle units, from once-through cooling to wet recirculating towers and dry cooling systems, and from traditional fresh and saline surface cooling water to reclaimed water and groundwater sources. Total US cooling water withdrawals and consumption volume decreased from 2008 to 2014. The average water withdrawn per unit of electrical output decreased over this time, while changes in water consumption rates stayed relatively flat. Changes in water use at the watershed scale were unevenly distributed, as some water-scarce regions experienced increases in cooling water usage for thermal power plants, while others experienced significant water reductions and environmental benefits, especially where coal-fired generation was retired or retrofitted. The results from this study underscore the importance of evaluating water withdrawals and consumption at local spatial scales, as the water extraction, water quality and environmental health consequences of power plants on downstream users are non-uniform.

Evaluating the Impact of Meteorological Factors on Water Demand in the Las Vegas Valley Using Time-Series Analysis: 1990–2014

Many factors impact a city’s water consumption, including population distribution, average household income, water prices, water conservation programs, and climate. Of these, however, meteorological effects are considered to be the primary determinants of water consumption. In this study, the effects of climate on residential water consumption in Las Vegas, Nevada, were examined during the period from 1990 to 2014. The investigations found that climatic variables, including maximum temperature, minimum temperature, average temperature, precipitation, diurnal temperature, dew point depression, wind speed, wind direction, and percent of calm wind influenced water use. The multivariate autoregressive integrated moving average (ARIMAX) model found that the historical data of water consumption and dew point depression explain the highest percentage of variance (98.88%) in water use when dew point depression is used as an explanatory variable. Our results indicate that the ARIMAX model with dew point depression input, and average temperature, play a significant role in predicting long-term water consumption rates in Las Vegas. The sensitivity analysis results also show that the changes in average temperature impacted water demand three times more than dew point depression. The accuracy performance, specifically the mean average percentage error (MAPE), of the model’s forecasting is found to be about 2–3% from five years out. This study can be adapted and utilized for the long-term forecasting of water demand in other regions. By using one significant climate factor and historical water demand for the forecasting, the ARIMAX model gives a forecast with high accuracy and provides an effective technique for monitoring the effects of climate change on water demand in the area.

Developing and quantifying indicators of organic farming using analytic hierarchy process

Although regulations and criteria relating to organic farming are clearly defined by the relevant agencies, especially by IFOAM, some have been overshadowed by attention to others and have lost their significance over time. The aim of this study was to develop and quantify organic farming indicators to determine the relative importance of each. The desired indicators were collected during a literature review of scientific resources about the principles of organic farming. These indices were classified into four categories and their weights were determined through interviews with experts on organic agriculture, including university professors, agroecology students, Ministry of Agriculture experts, organic farming inspectors and organic farmers. The analytic hierarchy process (AHP) was used for this purpose. The results showed that pest and disease management, yield, soil nutrient management, water consumption rate, chemical fertilizer consumption rate and the use of transgenic materials having weights of 0.16, 0.098, 0.096, 0.08, 0.071 and 0.059, respectively, and are the most important indicators for development and assessment of organic farming. In this as well as similar studies, the weight of indicators associated with consumption of chemical fertilizers and pesticides were relatively high. This indicates the importance of rules related to the use of chemicals in organic farming; however, each index has a certain weight and none can be overlooked. All indicators should be considered as an inseparable set and all should be used in the development of organic farming. The results of this study can be useful for both inspection bodies and organic farmers. Farmers can reduce the risks associated with transitioning to organic farming and minimize the probability of failure by monitoring these indicators in their fields.

A Hybrid Model for Forecasting Groundwater Levels Based on Fuzzy C-Mean Clustering and Singular Spectrum Analysis

Having the ability to forecast groundwater levels is very significant because of their vital role in basic functions related to efficiency and the sustainability of water supplies. The uncertainty which dominates our understanding of the functioning of water supply systems is of great significance and arises as a consequence of the time-unbalanced water consumption rate and the deterioration of the recharge conditions of captured aquifers. The aim of this paper is to present a hybrid model based on fuzzy C-mean clustering and singular spectrum analysis to forecast the weekly values of the groundwater level of a groundwater source. This hybrid model demonstrates how the fuzzy C-mean can be used to transform the sequence of the observed data into a sequence of fuzzy states, serving as a basis for the forecasting of future states by singular spectrum analysis. In this way, the forecasting efficiency is improved, because we predict the interval rather than the crisp value where the level will be. It gives much more flexibility to the engineers when managing and planning sustainable water supplies. A model is tested by using the observed weekly time series of the groundwater source, located near the town of Čačak in south-western Serbia.

Retrofit of a wet cooling tower in order to reduce water and fan power consumption using a wet/dry approach

A Parallel Path Wet/Dry configuration and a high-precision airflow regulation method are implemented in order to retrofit an existing wet cooling tower. The modifications are intended to reduce water requirements and fan power consumption of a 12-cell wet tower. The proposed method of airflow control takes advantage of fans with variable frequency drive to regulate airflow with high accuracy. A number of simulations are carried out to predict different operating factors of the wet and hybrid towers. Experimentally obtained values of water consumption demonstrate the validity of those obtained using the computer simulations. According to the results, the accurate airflow control prevents sudden fluctuations in requisite fan power and water consumption rate and causes up to 64.6% decrease in fan power consumption. The results reveal that using the proposed wet/dry approach results in an average 9.4% decrease in water consumption. Given the relatively low degree of modifications made to the original wet tower and preserving the condenser operating condition, the accomplished amount of water conservation is satisfactory.

English

Aim: The present study was conducted to investigate the haematological changes in layers experimentally infected with Salmonella gallinarum. Methods: A total of 20 eighteen-week- old ISA Brown layers were used for the experiment. The birds were randomly divided into two groups, infected and control, of 10 birds each. To establish the infection, each bird in the infected group was orally administered 0.5 ml of the inoculum containing 9x108CFU/ml. Similarly, birds in the control group were each administered 0.5 ml normal saline only. Following the inoculation, all experimental birds were closely monitored for clinical signs of fowl typhoid. Blood samples were collected from each group at day zero (Day 0), 2, 4, 7, 14, 21, 28, 35 and 42, post-infection (pi) and used for determination of haematological parameters. By day seven post infection, all birds in the infected group showed clinical signs typical of fowl typhoid; namely weakness, ruffled feathers, huddling together, somnolence, greenish-yellow diarrhea, weight loss, drop in egg production, decrease in feed and water consumption and mortality rate (50%). There were, however, macrocytic hypochromic anaemia, leuckocytosis and heterophilia. In conclusion, the experimental Salmonella Gallinarum infection induced acute anaemia, leukocytosis, heterophilia and lymphopenia.   Keywords; Fowl typhoid, Salmonella, Inoculum, Leukocytosis

A simplified experimentally tested theoretical model to reduce water consumption of a direct evaporative cooler for dry climates

The aim of this study is to introduce a simple modified experimentally tested theoretical model to mainly reduce the water consumption rate of a direct evaporative cooler type (DEC). The convective heat transfer coefficient correlations are introduced to the fundamental governing equations of this model and the saturation effectiveness of the DEC is calculated. The saline water at different concentrations is used as a feed water to the presented model. The impacts of inlet ambient air conditions and the salinity ratios on the amount of consumed water and the supply air temperature are investigated. The experimental runs are performed on a commercial type DEC and an average operating sprinkled water temperature is found to be 2.5 °C higher than inlet WBT of air. At 200,000 PPM salinity ratio, a reduction in water consumption by about 1.5 L h−1 is reached but with 8.6% increase in the supply air temperature.

THE ECONOMY FEASIBILITY OF IMPELEMNATTION WDS PROJECT IN MALA OMER CATCHEMNT AREA

The aim of the present study was to evaluate the Water Distribution System (WDS) and water distribution economy feasibility in light of Mala Omer research area that belongs to KR-I. Data have been collected regarded Mala Omer through site visits and interviews with stakeholders and it was then analyzed for information abstraction to assess the water distribution feasibility. Operation expenditures (OPEX) were estimated to 39% of the total revenue. The WDS network was not sufficient and new water paradigm was proposed working by gravity. The costs and revenue have been analyzed, the capital cost will require about five years. While the Internal Rate of Return (IRR) was 33.4%. The results of the study showed insufficient WDS with significance of the economy feasibility of the project. Family size should have significance consideration in water consumption and price rates.

Efficiency evaluation of hydropower station operation: A case study of Longyangxia station in the Yellow River, China

Hydropower plays a major role in the Chinese electricity generation industry. It is of significant importance to perform efficiency evaluation of the economic operation in a power station, which can help promote better water resources management and create more benefits for power network. Therefore, the main goal of this study is to establish a set of evaluation indexes and investigate the evaluation method to assess the economic operation in a power station. Based on the operation chart, three evaluation indexes including the Relative Water Consumption Rate (RC), the Relative Hydropower Utilization Rate (RU), and the Relative Hydropower Utilization Increasing Rate (RI) were proposed. The Longyangxia power station, as the biggest peak regulation source in the Northwest Power Network in China and the largest reservoir in the Yellow River Basin, was selected to perform an efficiency evaluation of economic operation. The result showed that the economic operation of this power station was not reasonable with RC > 1, RU < 1 and RI < 0. And the rationality of the evaluation result was illustrated through analyzing the actual operation situation of the Longyangxia reservoir.

The Water Footprint of Hydropower Production-State of the Art and Methodological Challenges.

This paper reviews published estimates of water consumption from hydropower production and the methodologies applied. Published values range from negative to more than 115 000 m3 MWh−1. Most gross water consumption rates are in the range 5.4–234 m3 MWh−1, while most net values are in the range 0.2–140 m3 MWh−1. Net values are often less than 40% of the gross values, sometimes only 1% of the gross water consumption estimates. The extremely wide range in estimates is explained by an inconsistent methodology and the very site‐specific nature of hydropower projects. Scientific challenges, such as allocation from multipurpose reservoirs, and spatial assignments in river basins with several hydropower plants, affect the results dramatically and remain unresolved. As such, it is difficult to propose “typical values” for water consumption from hydropower production. This paper points out directions of research in order to prepare a consistent and improved methodology for the calculation of water consumption from hydropower projects. This should take into account the role of reservoirs in the provision of a large range of water services, as well as providing regulated power to the energy system.

Integrated energy simulation of a deep level mine cooling system through a combination of forward and first-principle models applied to system-side parameters

Mine cooling systems typically account for around 25% of the total electrical energy consumption of deep level mines. Numerous energy saving strategies have been implemented, with various levels of success. Most of the previously implemented strategies involved load shifting, energy efficiency and demand reduction. To achieve this, some levels of control are often introduced to control chilled water consumption, water and air mass flow rates as well as scheduling cooling system operation in order to shift the load primarily to off-peak periods.To support and sustain further reduction of energy consumption and optimisation of savings, a simulation model of the integrated cooling system represented by smooth and continuous equations is needed to assist the optimisation computation. This study focused on developing such an integrated mine cooling system simulation model to mimic the thermal hydraulic behaviour along with the energy consumption of the complete mine cooling system. This was achieved by coupling various models representing the major cooling system components such as chillers, cooling towers, pumps and fans. Although various cooling system energy simulations were considered before, very few quantify the simulation accuracy on a component basis; furthermore, only limited cases were found where the entire system was considered. For these cases not all components were always based on explicit models which would eliminate the requirement for iterative computation which deter optimisation applications.The simulation model was used to predict the energy consumption of the integrated cooling system of a deep level gold mine in South Africa. The simulation model obtained an average error when compared to the mine’s system data of 3.5% for a selected dataset and 2.5% for another dataset one month later. The successful energy simulation of an integrated mine cooling system would allow for a holistic view on the total power consumption as one parameter or any combination of parameters of the system changes.