Minimum Water Consumption Research Articles

CONTROL OF WATER CONSUMPTION OF ENTERPRISES OF ROSTOV REGION

. In this paper we consider the hierarchical two-level dynamic model of water consumption of enterprises of Rostov region. On the top level there is region’s government (supervisor) and on the lower level there are enterprises grouped by the types of economic activity. Such grouping allows one to avoid modelling all region’s enterprises which consumes water (there were about 500 enterprises in 2019) while still considering the uniqueness of the enterprises. We consider three groups of enterprises which, according to statistics, are the main water consumers. The enterprises aim to maximize their production while supervisor seeks to minimize water consumption and to maximize production. We introduce generalized goal function for supervisor, which it seeks to maximize depending on what it values the most – production or water consumption. Using the model, we study how supervisor is able to control water consumption of the enterprises with extra fees and how it may affect production level. We provide algorithms for model identification and study. For model identification we use least squares method and the data from publicly available sources. To study model we use Pontryagin’s maximum principle and quality representative scenarios method. We provide various calculations for the model with different supervisor’s preferences. We show that it is possible to reduce water consumption by more than 50 % with production decrease being less than 25%

The implementation of green industry standard batik industry to develop eco-friendly

Since UNESCO has established batik as Indonesia’s cultural heritage, batik has become increasingly recognized internationally. However, many parties are concerned about environmental problems due to the waste from the batik production process. Therefore, the batik industry must change its thinking about the concept of environmentally friendly industries by applying green industry principles. This paper will explain the application of green industry principles that can be fulfilled at every stage of the batik production process. The technical and management requirements are covered by the Green Industry Standard (GIS) for the batik industry which is stipulated by the Minister of Industry Regulation Number 39 of 2019. GIS includes the efficiency of input materials, namely raw and auxiliary materials as well as the selection of alternative materials that are more environmentally friendly, energy-efficient and minimize water consumption and pay attention to the principles of water conservation, good waste treatment, and limitation of air emissions due to the use of technology and low-carbon energy options. It is expected that with the application of green industry principles, the batik industry will not only experience an increase in the economic sector but become an environmentally industry.

Cooling water sources diagram

Recirculating cooling water systems are used to absorb heat in the heat exchanger network, usually operating in a parallel configuration and returning water to the cooling tower with a higher temperature. This configuration receives the fresh cooling water directly without any previous reuse. While this configuration is simple to operate, it leads to inefficient use of the cooling water. On the other hand, a series configuration can reduce the cooling water flow rate, but the complex arrangement and sometimes thermodynamic restrictions lead to higher operational costs. This paper proposes simplifying the network structure through a series-parallel configuration and determines the minimum water flow rate in the cooling system without affecting the heat load removal from the process heat exchangers, using the Cooling Water Sources Diagram (CWSD). Minimizing water consumption and increasing the water return temperature lead to an improvement in the cooling tower's efficiency, which reduces its operational cost. One case study with different scenarios is presented to cover several cooling system characteristics to demonstrate the proposed new tool's applicability and efficiency. The results are compatible with those observed in the literature, being superior in some cases, either in terms of cost values or generating different possible networks.

Modeling oasis dynamics driven by ecological water diversion and implications for oasis restoration in arid endorheic basins

To achieve sustainable development, ecological water diversion has been implemented as a management tool to recover degraded oasis ecosystems in arid endorheic basins. Aiming to explore oasis response and identify appropriate objectives for oasis restoration, this study used a conceptual lumped ecohydrological model. Qingtu Oasis in the Shiyang River basin, Northwest China, was used as a case study to test this model. The model coupled groundwater budget, oasis response, and evapotranspiration dynamic modules. The model structure was clear and reasonable, and the calculation was of low cost. The application in Qingtu Oasis verified the model's effectiveness. The model was able to effectively capture the ecohydrological response attributed to the recovering of Qingtu Oasis in response to ecological water diversions occurring during the last decade. Combined with scenario analysis, the simulation indicated that Qingtu Oasis was fragile and largely dependent on ecological water diversion. Ecological responses were positive and non-linearly correlated with water input, resulting in an optimal water input that produced maximum water benefit by minimum water consumption. The ideal point method was useful in identifying this cost-effective water volume for oasis restoration. For Qingtu Oasis, the optimal water diversion was 45 million m3, which would recover the oasis to 29.16 km2 with an NDVI of 0.41. The current oasis conditions approach the optimal status, and ecological water diversion was suggested to continue and maintain the current oasis status. The volume of 45 million m3 could be taken as an upper threshold of water diversion, because above this threshold, water consumption would not result in water benefits effectively. This study proposed a practical tool for ecohydrological process simulation.

Study of optimal allocation of water resources in Dujiangyan irrigation district of China based on an improved genetic algorithm

Abstract In order to distribute water resources reasonably, it is advantageous to make full use of resources and produce high economic and social benefits. Taking the Dujiangyan irrigation area of China as an example, we discuss the idea of establishing and solving the optimal allocation model of water resources. With this aim, a two-dimensional constraint model with highest economic value, minimum water shortage, minimum underground water consumption and necessary living water demand was established. In order to solve this model, we improved a multi-population genetic algorithm, extending the genetic optimization of the algorithm into two dimensions, taking population as the vertical dimension and the individual as the horizontal dimension, and transforming the cross genetic operator to copy the genetic (crossover) operator and the mutation operator to only act on the vertical dimension, so as to optimize the allocation of such discrete objectives of water resources in the irrigation area with a particular model suitable for the region. The distribution results successfully control the water shortage rate of each area at a low level, which saves the exploitation of groundwater to the maximum extent and produces high economic benefits. The improved algorithm proposed in this paper has a kind of strong optimization ability and provides a new solution for the optimization problem with multiple constraints.

Performance evaluation of shell and tube heat exchanger through ANN and ANFIS model for dye recovery from textile effluents

ABSTRACT Performance of Shell and Tube Heat Exchanger for treatment of textile industry wastewater as a secondary treatment process is reported. An Adaptive Neuro-Fuzzy Inference System and Artificial Neural Network models were used for predicting the accuracy of the process. Condensate flow (m3/hr), feed inlet temperature (°C) and steam flow (kg/cm) for textile effluents were used to predict the condensate temperature (°C). The accuracy of the developed model was validated using Absolute Mean Relative Error, Root Mean Square, and Absolute fraction of variance. The different combinations of input parameters were determined with preceding parameters of the model. Comparison of the models indicated the advantage of ANFIS model over ANN model. Seventh configuration values of ANN reported 0.971%, 1.175%, and 0.9456 of the Absolute Mean Relative Error, Root Mean Square, and Absolute fraction of variance respectively. Similarly, the ANFIS reported 0.381%, 0.532%, and 0.9998 of the Absolute Mean Relative Error, Root Mean Square, and Absolute fraction of variance respectively. ANFIS model was found to be more effective in predicting the condensate temperature with a high Absolute fraction of variance R2 = 0.9998 the results were in line with the experimental data. In the present study the complication of nonlinear process has been resolved using ANFIS modeling technique. The treated water could be recycled using this process. Optimization of the process parameters helps in minimizing water consumption and offers economic benefits for wastewater treatment.

A case study on the treatment and recycling of the effluent generated from a thermo-mechanical pulp mill in Brazil after the installation of a new bleaching process

A Brazilian thermo-mechanical pulp mill (TMP) was evaluating the installation of a proposed bleaching process, with changes in the qualitative and quantitative characteristics of the wastewaters and the Effluent Treatment Plant (ETP). The objectives of this research were to evaluate the treatment plant configuration for the future industrial effluent, consisting of a flotation unit followed by an upflow anaerobic sludge blanket reactor (UASB), an activated sludge process and nanofiltration (NF) using polymeric membranes, and to study the technical feasibility of recycling the treated effluents in the industrial process. The possible options for recycling the treated effluent were determined through a water balance of the mill. The pulp quality was evaluated in laboratory bleaching assays, based on brightness and brightness reversion tests after the recycling of 50%, 75% and 100% of the treated effluent. The buildup of the non-process elements (NPE) in the industrial water cycle after each effluent recycling proportion was evaluated through computer simulation, using the Aspen Plus® simulator software. The future mill effluent, considering the implementation of a proposed bleaching stage with hydrogen peroxide, was generated in the laboratory and treated in a bench-scale effluent plant, simulating the future configuration. The treatment plant removed 99.8%, 99.2% and 61.6% of soluble COD, BOD5 and color, respectively. The water consumption was highest in the bleaching plant and, therefore, the recycling of 50%, 75% and 100% of the treated effluent for washing the pulp was simulated. The brightness and brightness reversion of the pulp, with 100% of the treated effluent used in the bleaching process, were similar to those provided by fresh water. The recycling of 100% of the treated effluent in the proposed treatment plant was possible in the TMP pulp mill without decreasing the pulp quality.

Concentration and purification by crossflow microfiltration with diafiltration of carotenoids from a by-product of cashew apple juice processing

This work aimed to further investigate microfiltration with diafiltration to obtain a rich carotenoid extract from the solid by-product of cashew apple (Anacardium occidentale L.) juice processing. This solid residue called cashew fibers is rich in bioactive compounds, especially carotenoids. After mixing with water and pressing, an aqueous suspension was obtained and processed by crossflow microfiltration (40 °C) using tubular ceramic membrane with 0.2 μm pore diameter. Permeate flux, which increased with transmembrane pressure, could be maintained above 100 L·h−1·m−2 at high volume reduction ratio by coupling mechanical extraction with enzyme liquefaction. The concentration step led to an increase of the carotenoid content by up to 19-fold and the diafiltration step allowed the carotenoid purity to be multiplied by 5. The impact of the process on the retentate characteristics was assessed using a model based on simple assumptions. This calculation tool can easily be implemented and is helpful for choosing the operating conditions, to minimize water consumption as well as effluent production.

Mathematical modeling and study on the application of cross flow direct evaporative cooler under different indoor and outdoor environmental conditions

Performance of a cross flow direct evaporative cooler under different indoor and outdoor conditions was investigated by a thermodynamic model and using finite difference scheme. Unlike the previous studies, the temperature variation of water film during the evaporation process was included among the modeling, and the error of the mathematical model to estimate the effectiveness of the cooler became lower than the error reported in the literature. To achieve the comprehensive results and evaluation of the applicability of the system under real conditions, the performance of the cooler in ambient temperatures of 25, 30, 35 and 40 °C, relative humidities of 10, 30, 50 and 70% and cooling demand of 1–5 kW for a building with air changes of 5, 10 and 15 per hour was investigated. Lastly, the study on the performance of the cooler in different Iranian provincial capitals showed that for air change of 15 per hour and cooling demand of 1 kW, the system could provide thermal comfort conditions in 24 provincial centers while for air change of 5 per hour and cooling load of 5 kW, this goal cannot be achieved in any centers. Moreover, comparing the water consumption of the coolers showed that the maximum and minimum daily water consumption was for Yazd in September and for Kermanshah on July, respectively. Investigation of the coefficient of performance of the system for air changes of 10 and 15 per hour revealed that Khoramabad and Bandar Abbas had the maximum and minimum coefficients of performance, respectively.

Analysis of the heat budget of standard, cool and watered pavements under lab heat-wave conditions

The thermal behavior of 12 standard and cool pavement structures (asphalt, granite, stabilized sand, cobblestones, reflective paints, pervious concretes, dry grass, etc.) coupled with pavement-watering is studied in the lab under heat-wave-like conditions. Watering is fine-tuned for each structure to maximize cooling and minimize water consumption using two linear cooling regimes, before deployment in the field. The surface heat budget is closely studied and the partitioning of irradiance and net radiation into conductive, convective, radiative and cooling flux at surface is analyzed for each structure. Energy partitioning, surface temperature increase and optimal watering rates all exhibit good correlation with overall surface absorptivity. The transmitted flux at varying depths is also characterized using a transmission index that includes surface absorptivity and apparent conductivity of the traversed layers. Results of this study intend to improve our understanding of the energy balance of cool pavements compared to traditional ones under given weather conditions, as well as that of processes involved in the optimization of their evaporative cooling versus watering rate. Benefits of each pavement, efficiency of the method, limitations of the protocol and its potential transposition to the field are all discussed in this contribution.

Minimum water consumption method screening of velvet bean (Mucuna sp.) processings to produce functional food ingredients

Velvet bean (Mucuna sp.) has been proven containing many beneficial compounds that can be implemented in pharmaceutical and medicines but less noticed for functional foods even though traditionally it is consumed as daily foods or snacks. The indigenous food preparation such as velvet bean Tempe warrants scientific investigation to help society with better public health management. The objective of the review is to select the best method for functional food ingredient product development using velvet beans and provide hypothetical health-oriented food processing e.g. velvet bean flour as functional food ingredients with a focus on less water consumption during processing. Steaming is the selected method.

Cover Crop Selection by Jointly Optimizing Biomass Productivity, Biological Nitrogen Fixation, and Transpiration Efficiency: Application to Two Crotalaria Species

Crotalaria spectabilis and Crotalaria juncea are cover crops (CC) that are used in many different regions. Among the main attributes of these species are their high potential for biomass production and biological fixation of nitrogen (BNF). Attempting to maximize these attributes, while minimizing water consumption through high transpiration efficiency (TE), is a challenge in the design of sustainable agricultural rotations. In this study, the relationship between biomass productivity, BNF, and TE in C. spectabilis and C. juncea was evaluated. For this purpose, an experiment was carried out under controlled conditions without water limitations and using non-inoculated soil. BNF was determined by the natural abundance of 15N, while TE was estimated by several different methods, such as gravimetric or isotopic method (13C). C. juncea produced 42% less dry matter, fixed 28% less nitrogen from the air, and had 20% less TE than C. spectabilis. TE results in both species were consistent across methodologies. Under simulated environmental conditions of high temperature and non-limiting soil water content, C. spectabilis was a relatively more promising species than C. juncea to be used as CC.

Toward the reduction of water consumption in the vegetable-processing industry through membrane technology: case study of a carrot-processing plant.

The food industry consumes large amounts of clean, potable water and in turn generates a significant amount of wastewater. In order to minimize water consumption, membrane technologies represent a suitable solution for the treatment of wastewater before it is recycled as process water. Many studies have shown the effectiveness of this technology in the dairy industry, but there are few studies in the fruit- and vegetable-processing sectors. A recently developed methodology for the reduction of water consumption was tested here. Compounds to be eliminated were identified through chemical analysis of several wastewater samples from a carrot-peeling process. Drinking-water quality was selected as our target. Total suspended solids (TSS), fructose, glucose and sucrose were identified as key parameters. Salts (particularly Ca2+ and Mg2+), pH and carbonate hardness (CH) were identified as indicators for evaluating the risk of scaling and corrosion. Based on these results, sieving followed by a 0.5-μm microfiltration (MF) was chosen as the process for pre-treatment. Four nanofiltration (NF) membranes (NFW from SYNDER, DK from GE, NF270 from DOW and SR3D from KOCH) and three reverse osmosis (RO) membranes (ESPA4 from Nitto Group Company, BW30 from DOW and HRX from KOCH) were then tested for the capacity to minimize chemical oxygen demand (COD) and to principally remove sugars. These membranes were then evaluated in terms of permeability and rejection rates. High-quality water could be obtained with RO membranes at low pressure (up to 15bar) while limiting fouling risks. Rejection rates up to 98.3, 98.0, 99.2, 99.2 and 99.4% for conductivity, COD, fructose, glucose and sucrose, respectively, were achieved. These results are very encouraging for future reuse in vegetable processing before the blanching step, after an additional disinfection treatment.

Design of a water curtain to reduce accumulations of float coal dust in longwall returns

Accumulation of float coal dust (FCD) in underground mines is an explosion hazard that affects all underground coal mine workers. While this hazard is addressed by the application of rock dust, inadequate rock dusting practices can leave miners exposed to an explosion risk. Researchers at the National Institute for Occupational Safety and Health (NIOSH) have focused on developing a water curtain that removes FCD from the airstream, thereby reducing the buildup of FCD in mine airways. In this study, the number and spacing of the active sprays in the water curtain were varied to determine the optimal configuration to obtain peak knockdown efficiency (KE) while minimizing water consumption.

HYDROPHILIC POLYMER CHANGES THE WATER DEMAND IN THE IMPLEMENTATION OF A DWARF CASHEW ORCHARD

Abstract: Important losses of dwarf cashew seedlings during the establishment of orchards in the Brazilian semiarid are related to the relatively short rainy season. This study aimed to evaluate biochar and hydrophilic polymer as soil amendments to increase water retention and reduce plant death in the first year. An experiment was conducted at the Curu Station, Paraipaba, CE, Brazil, using the clone BRS 226. The experimental design consisted of randomized blocks, with amounts of 0.5, 1.0, 2.0, and 4.0 kg of cashew wood biochar and 20, 40, 60, 80 g of hydrophilic polymer applied per pit, as well as a control treatment (no soil amendment). Seedlings were submitted to an irrigation regime to avoid water stress (5 L water seedling-1 when the tensiometer installed at a depth of 0.15 m reached 60 kPa). The variables of plant development number of leaves, plant height, stem diameter, and canopy diameter were evaluated up to 374 days after transplanting to the field. The analysis of variance showed no treatment effect on plant development. However, minimum water consumption was observed when 29.56 g of hydrophilic polymer was applied per pit, providing 100.0% seedling survival.

Assessing the socio-demographic, economic and water source types that influences households drinking water supply in Debre tabor town, north-west Ethiopia

Background: Human life depends on clean and healthy environment. However, low environmental standards lead to reduced life expectancy. Most peoples who live in the developing countries are under risk of getting clean water and any form of sanitation services. Because of this, millions of peoples are suffering from diseases associated with water. Nowadays, it needs emphasis on the accessibility of drinking water and factors which determine the supply of safe drinking water for urban households. Objectives: This study aimed to assess socio-demographic, economic and water source types that influences households drinking water supply in Debre Tabor Town, North-West Ethiopia. Methods: A community based cross-sectional study design was conducted among households from February to March 2019. An interview-based pre-tested and structured questionnaire was used to collect data. Data collection samples were selected randomly and proportional to each kebeles. Epi info version 7.2.1.0, and SPSS Version 24 were used to enter and analyze the data; respectively and descriptive statistics with frequency counts and simple percentages were performed. Results: 418 households were participated. On average there were about 4.53 persons per each household. The most frequently used water source is pipe water (78.95%). Fetching water was the responsibility of females and children. Majority of the population of the town had no alternative sources, since traditional water sources were polluted by animal and human wastes. Due to high scarcity of water supply, traditional water sources were used by the residents. The time taken from home to traditional water sources was about 55.74% of the population had got their water for a trip of 15-30 minutes and 35.17% of the population 31-45 minutes, was much longer than the country average. 44.50% of the population got their water supply partially per week. 91.15% of the population was under the problem of water scarcity in the town. About 85.65% scarcity was happened due to weak administration of the concerned government bodies. Conclusion: The water supply was inadequate, and the quality was low. The median consumption was found to be 30 liters per household per day and 6.62 l/p/d, lower than the national and WHO minimum water consumption level of 20 l/p/d. Nine out of ten persons was under the problem of water scarcity in the town. The concerned government bodies should provide adequate and quality potable water facilities for the town residents.

Electricity savings by reducing water consumption in a whole city: A case study in Joinville, Southern Brazil

This paper aims to propose a method to estimate the electricity savings in water supply and sewage systems due to the reduction of potable water consumption on a city scale. The method was applied in a case study in Joinville, a city located in Southern Brazil. The strategies considered to promote water savings were: replacement of toilets, greywater reuse, rainwater harvesting and combination of these three strategies. Single-family residential, multi-family residential, public and commercial sectors were assessed. For each building sector, minimum and maximum potable water consumption and sewage generation reductions due to each strategy were determined, so the range of possible electricity savings in water supply and sewage systems were estimated. The financial feasibility of adopting these strategies was verified using data from the National Information System on Sanitation and local utility. The most significant energy savings were provided by the simultaneous adoption of the three strategies (from 2136.8 MWh/year to 8951.5 MWh/year). However, greywater reuse and rainwater harvesting presented savings similar to those provided by the three strategies. The single-family residential sector led to the highest energy savings, corresponding to more than 50% of total electricity savings in seven of eight cases analysed, while the smallest contribution was from the public sector. The local utility would not fail to profit in any of the scenarios analysed. Thus, in addition to the environmental benefits of water savings, lower sewage generation and electricity savings, the local utility would also profit from adopting these strategies on a city scale.

Short-Term Optimal Operation of Baluchaung II Hydropower Plant in Myanmar

The short-term optimal operation model discussed in this paper uses the 2016 to 2018 daily and monthly data of Baluchaung II hydropower station to optimize power generation by minimizing water consumption effectively in order to get more revenue from optimal operation. In the first stage, run-off-river type Baluchaung II hydropower station data was applied in a mathematical model of equal micro-increment rate method for optimal hydropower generation flow distribution unit results. In the second stage, dynamic programming was used to get optimal hydropower generation unit distribution results. The resultant data indicated that optimized results can effectively guide the actual operation run of this power station. The purpose of the optimal load dispatching unit was to consider the optimal power of each unit for financial profit and numerical programming on the actual data of Baluchaung II hydropower plant to confirm that our methods are able to find good optimal solutions which satisfy the objective values of 17.75% in flow distribution units and 24.16% in load distribution units.

Mechanocatalytic Synergy for Expedited Cellulosic Ethanol Production Compatible with Integrated Biorefinery

Developing economically viable cellulosic ethanol process requires concentrated fermentable sugars and minimum water consumption. Biorefinery economics requires highly integrated efficiencies in the full utilization of all biomass components. Toward this objective, we have developed an enzyme-free mechanocatalytic saccharification process that combines mix-milling of P2O5 with lignocelluloses and successive hydrolysis into fermentable sugars. Demonstrated with corn stover (CS) and CS-xylose residues, after recovery of valuable hemicellulose, fermentable glucose in 75% yield at a high biomass loading (92 mg/mL) was obtained with concomitant precipitation of pristine lignin. The undetoxified concentrated hydrolysate allows for fermentative upgrading, achieving 42 g/L ethanol (a benchmark (40g/L) for an economically feasible bioethanol process) in 52 h after hemicellulose is converted into xylose. P2O5 is essential in fragmentation of cellulose in the milling stage and subsequent accelerated hydrolysis to gl...

Stochastic Economic Dispatch of Hydro-Thermal-Wind-Photovoltaic Power System Considering Mixed Coal-Blending Combustion

This paper proposes a stochastic economic dispatch (SED) model for hydro-thermal-wind-photovoltaic power system (HTWPPS) considering mixed coal-blending combustion (MCBC) to improve the operational efficiencies of thermal power units (TPUs) with deep peak-regulating operation (DPRO). Firstly, the rations for different types of coal can be acquired by meeting the operational requirements of boilers. Three functions including the cost of coal consumption, polluting gas emission, and the life loss cost for TPUs could be obtained by fitting coal quality. Besides, they would be strictly piecewise linearized, respectively. Consequently, the objective function involving the above three kinds of costs as well as the cost of oil injection can be presented. Secondly, there is a two-stage framework for reducing the coupling of HTWPPS and improving the solving efficiency. In the first stage, the Monarch Butterfly Optimization (MBO) algorithm is employed for obtaining the power outputs of hydro-power units (HPUs) taking the minimum water consumption as the objective. In the second stage, the load curve can be updated according to the results from the first stage. Besides, the Latin Hypercube Sampling method and the backward scene reduction technique are utilized to acquire a set of scenarios of wind power. In this way, the SED model considering MCBC can be achieved. The case studies have been carried out on a simplified provincial power system in China with the help of MATPOWER and CPLEX. The results show that the proposed model can effectively increase the economic and environmental benefits for TPUs.