Cubic Meters Of Water Research Articles

Bridge the gap: Consumers’ purchase intention and behavior regarding sustainable clothing

With the textile industry satisfying steadily increasing consumption levels, excessive usage of valuable natural resources provokes a major environmental footprint: 118 billion cubic meters of water are expected to be utilized for global clothing production in 2030. Therefore, consumers' clothing consumption behavior needs to be shifted towards a more sustainable one. While green purchase behavior in general is well understood, research still lacks a comprehensive approach to explain consumers' purchase behavior of sustainable clothing. To provide a holistic framework which determines the main antecedents of purchase behavior of sustainable clothing and further, to shed light on the gap between purchase intention and subsequent purchase behavior of such clothes, we extended the Theory of Reasoned Action (TRA) approach with well-established constructs from green literature (i.e., perceived environmental knowledge and environmental concerns) and novel constructs derived from prior exploratory findings (i.e., greenwashing concerns, perceived economic risk, and perceived aesthetic risk). Four hundred sixty-four participants were inquired to assess these constructs in the context of sustainable clothing. Our findings indicate that attitude towards sustainable clothing has the highest impact on purchase intention. However, this relation is negatively influenced by consumers' greenwashing concerns. Moreover, we find evidence that consumers’ perceived aesthetic risk negatively impacts the intention-behavior relation, whereas perceived economic risk has no significant effect on this relation.

Integration of UAV data with soil water balance models for evaluation/monitoring of maize water stress

UAV based photogrammetry and 3D mapping are gaining fast and wide applications around the world majorly due to the relatively low-cost advantage it offers in the acquisition of high resolution multispectral acquisitions, compared to Aerophotogrammetry and satellite acquisitions. This research seeks to demonstrate the applicability of UAV photogrammetry visible, multispectral and thermal in investigating some physiological indexes of plants, reflecting plant physiological traits. A maize field in Latina (Italy) was acquired using a Fly Novex drone and with different cameras for the various acquisitions and consequently for different flight heights. The obtained images were processed using different photogrammetric models and a variable number of Ground Control Points (GCPs) for the georeferencing and accuracy assessment as well. Subsequently, by combining hydrological simulation methods and the use of physical indicators of the state of water stress, a method is proposed for predicting crop water consumption. The study conducted on the agricultural land of test site has provided useful results in terms of water savings, with an estimated value of three quarters of the total cubic meters of water needed to bring the land to saturation.

Reúso del agua de producción de hidrocarburos: reto y oportunidad

La explotación de gas y petróleo demanda millones de metros cúbicos de agua que se convierten en residuo. Esta agua de producción (AP) se reinyecta en los pozos o se vierte en la naturaleza; solo un mínimo volumen es tratado para ser reutilizado en la industria o la agricultura. El reúso es la opción más responsable porque implica devolver agua regenerada al ciclo natural, transformar en activo nuestro pasivo ambiental, alargar la vida del recurso, reducir los vertimientos y proteger la seguridad alimentaria de las poblaciones locales. Si bien el reúso del agua es ineludible para algunos países, debería serlo para todos. Si el AP es un bien y no un residuo, y su gestión es clave en la transformación hacia la economía circular, debemos reflexionar respecto al reto para la sostenibilidad y la oportunidad de alianza y negocio que representa. A continuación, se exponen aspectos generales y particulares del AP en Colombia, en donde el reúso fuera de la industria, es menos del 0,3% anual, mientras que el vertimiento sigue siendo una práctica usual de gran impacto sobre los ecosistemas. El desconocimiento sobre la tecnología disponible, los costos de inversión, la legislación y la necesidad de alianzas, son retos para lograr los beneficios del reúso; no solo respecto a su calidad y cantidad en la naturaleza, sino a los negocios emergentes que surgirían como oportunidades de mercado responsable en torno a un bien común.

Potentialities of water charge in the management of Brazilian water resources

We investigated the application of economic instruments in the management of Brazilian water resources as mechanisms to stimulate the rational use of water and to recognise its economic value. We analysed water-charge scenarios at the national and international levels as a methodology to provide an economic estimate of environmental services related to water resources. Through bibliographical and documentary research, we identified the economic instruments applied to Brazilian water-resource management, describing the methodologies and values used Brazilian water charges and in some member states of the Organization for Economic Cooperation and Development. We identified how economic valuation methods of environmental resources could contribute to the improvement of water charges, considering the environmental services offered by a healthy river basin. In the Brazilian and the international scenarios, water charge methodologies include the volumetry of abstracted or consumed water, associating some elements that indicate the pollution level. The prices per cubic meter of water are still very low in all the scenarios. Environmental valuation techniques can be an essential tool for rethinking the methodologies and costs applied in water charges, increasing the potential of water’s rational use through economic instruments.

Gray Water Measurement and Feasibility of Retrieval Using Innovative Technology and Application in Water Resources Management in Isfahan-Iran

Reuse of wastewater for agriculture and green spaces purposes is significant. A mean yearly precipitation in Esfahan is 150 mm. The drinking water and agriculture usually used underground resources in the city. Gray water recycling is known as a suitable option today. Delivering all the water requirements of a home from refined water rises the cost of water. Whereas the essential water quality for garden, toilet and irrigation is less than drinking water. Therefore, the aim of this study is to analyze the evaluation of gray water and estimate the amount of recycle gray water which can use for drinking water with innovation method in Esfahan region in Iran. Previous studies did not measure the value of recycling gray water with new method of waste water treatment that can use for drinking purpose. In this study,gray water in Esfahan city is measured and technical aspects of its recycling is examined. Because of the lack of referable guidelines and official technical reports, studies from other similar countries applied in this study and on the basis of which the amount of recoverable gray water was calculated.Evaluations indicates that the overall recovery of gray water in Esfahan saves nine million cubic meters of water. The price of the rial of this value established on water is 190 billion Rials. Given the lack of water sources in Esfahan, the recycle of gray water seems to be a good option, however more research is required to select a recovery strategy.

Accurate voidage prediction in fluidisation systems for full-scale drinking water pellet softening reactors using data driven models

In full-scale drinking water production plants in the Netherlands, central softening is widely used for reasons related to public health, client comfort, and economic and environmental benefits. Almost 500 million cubic meters of water is softened annually through seeded crystallisation in fluidised bed reactors. The societal call for a circular economy has put pressure on this treatment process to become more sustainable. By optimising relevant process conditions, the consumption of chemicals can be reduced, and raw materials reused. Optimal process conditions are feasible if the specific crystallisation surface area in the fluidised bed is large enough to support the performance of the seeded crystallisation process. To determine the specific surface area, crucial variables including voidage and particle size must be known. Numerous models can be found in the literature to estimate the voidage in liquid-solid fluidisation processes. Many of these models are based on semi-empirical porous-media-based drag relations like Ergun or semi-empirical terminal-settling based models such as Richardson-Zaki and fitted for monodisperse, almost perfectly round particles. In this study, we present new voidage prediction models based on accurate data obtained from elaborate pilot plant experiments and non-linear symbolic regression methods. The models were compared with the most popular voidage prediction models using different statistical methods. An explicit model for voidage estimation based on the dimensionless Reynolds and Froude numbers is presented here that can be used for a wide range of particle sizes, fluid velocities and temperatures and that can therefore be directly used in water treatment processes such as drinking water pellet softening. The advantage of this model is that there is no need for applying numerical solutions; therefore, it can be explicitly implemented. The prediction errors for classical models from the literature lie between 2.7 % and 11.4 %. With our new model, the voidage prediction error is reduced to 1.9 %.

Development of a Model and Sensor Based Smart Irrigation System

Water availability is a critical variable for virtually every economic activity, including agriculture and industry, the energy sector and public use. Specifically, Farmers could waste thousands of cubic meters of water daily through Irrigation. This project developed a smart irrigation system capable of making autonomous decision of irrigating the soil with an appropriate amount of water required through monitoring of soil irrigation factors. The soil moisture level and the rainfall status were the soil irrigation factors considered. The threshold values of the irrigation factors required for soil to be irrigated were established. Subsequently, a system was developed to sense the soil irrigation factors and monitor when the threshold values are reached so that necessary information is communicated to switch on or off a water pump designed for irrigation purpose. The system is implemented with a PIC16f876A microcontroller. The results of performance evaluation conducted on the system revealed that the system is able to monitor and estimate the soil irrigation factors with good accuracy. Also, the system is able to start the water pump to irrigate soil and stop it as appropriate depending on whether the soil irrigation factors value indicates need for irrigation or not.
 Keywords: Irrigation; Autonomous; System; Microcontroller; Threshold.

Water Defluoridation Using Sequentially CoupledMoringa oleiferaSeed Extract and Electrocoagulation

AbstractMoringa oleifera(MO) seed extract coupled with electrocoagulation (EC) was used to remove fluoride from water. Different MO extract volumes (5.0, 12.5, and 25.0 mL of MO extract per water liter) were coupled with EC, using aluminum electrodes at different current density values (J = 0.7, 2.0, and 3.3 mA/cm2) and different electrode separations (1.0, 2.0, and 4.0 cm), tested in batch and recirculation experiments. Control experiments using MO extract and EC alone achieved 5% and 54% water defluoridation, respectively. Best experimental batch conditions were achieved using 12.5 mL of MO extract followed by EC (3.3 mA/cm2) with a 1.0 cm electrode separation, producing >90% fluoride removal. Recirculation experiments with the EC reactor were performed with DI water and tap water using 1.0 cm electrode separation, 12.5 mL of MO extract and different current densities. More than 90% fluoride removal was achieved with the EC/MO process, using 3.3 mA/cm2, in both DI and tap water after 30 and 60 min, respectively. An energy consumption index (ECI) was developed, which showed that 1.51 and 0.67 W/h/mg were achieved for batch experiments of EC alone and EC/MO extract, respectively. For EC/MO extract, recirculation experiments with tap and DI water resulted in 0.35 and 0.22 W/h/mg, respectively. A cost analysis showed that $0.18 will be needed to treat one cubic meter of water.

The Water Project of the Israeli Middle East Channel and its Geopolitical Repercussions on Arab Water Security

Jordan and Israel agreed on the establishment of a water navigation project linking the Red Sea and the Mediterranean Sea. The agreement included in the light of the peace agreement between them in 1994. The project is the largest economic cooperation between the Zionist entity and Jordan in decades and a huge project represented in the establishment of a water link with a length of two hundred kilometers between the Mediterranean, the Red Sea and the Dead Sea, the lowest point on the surface of the earth. They have already signed an official agreement. The cost of the project may reach eleven billion dollars, with a clear and influential presence of the World Bank and the United States as sponsors of the agreement and donors among the countries funding the project. Israel gave Jordan an incentive to sign represented by fifty million cubic meters of water annually provided by Tel Aviv to Amman from the Sea of ​​Galilee.

Freshwater use of the energy sector in Africa

The fast economic and population growth in the African continent will lead to an important increase in demand for energy and water resources. Unfortunately, very few studies have addressed water use for energy production in Africa. This study focuses on water consumption and withdrawals throughout the different stages of energy production (fuel production, power plant construction and operation) in African countries. An in-depth analysis of water loss through evaporation in hydropower reservoirs is also performed due to the important role it plays in many countries and its severe impacts on electricity generation during the increasingly frequent droughts in Africa. The results indicate that in the year 2016, a total of 42 billion cubic meters of water was lost through evaporation in hydropower reservoirs compared to 1.2 billion cubic meters from all the other fuel types combined. Oil extraction and refining dominate water use for fuel production and non-hydro renewable energies have an almost negligible impact on the overall water use (10 million cubic meters). Fuelwood is shown to be a high consumer of water accounting for 4.5 billion cubic meters. The use of non-hydro renewable energies instead of fossil fuels can contribute significantly to reduce water use while covering the growing energy needs in Africa. Modern technologies that substitute fuelwood use in households would also reduce the impacts on water resources. The hydropower potential remains largely untapped in several regions of the continent. Nevertheless, new hydropower developments need to be carefully considered especially in regions characterized by severe water scarcity.

Water and fertilizer efficiency in a polyculture cropping system under three production systems

Abstract Approximately 40% of the water used in intensive agriculture is discarded as ‘drainage,’ which contains high amounts of ions that pollute the environment. This work aimed at investigating polyculture (tomatoes, cucumbers, and lettuce) under three production systems, namely, open (OPS), soil (SPS), and closed (CPS), in which the drainage water from the first crop was used to feed the second crop, and the water from the second crop was used to feed the third crop. The water and fertilizer efficiencies and some physical–chemical properties of the plants and soil were measured. The results showed no significant difference in the yield for polycultures between the CPS and OPS systems. The most efficient system for water use was the CPS, with 54.85 kg m−3, with a water savings of 55.69% compared to the OPS. The efficiency of fertilizers, such as N, P, K, Ca, and Mg, was statistically higher in the CPS, providing more kilograms of fruit per kilogram of nutrients. The reuse of drainage water in a polyculture not only increased the efficiency of the water and fertilizers but also increased the yields produced per cubic meter of water used, thereby minimizing environmental contamination.

Biochar and its impact on soil properties, growth and yield of okra plants

Applying biochar to the soil can mitigate problems that hinder agricultural production, such as water scarcity and low fertility soils. The objective of this research was to evaluate the impact of dry coconut husk biochar and sewage sludge combinations on soil chemical characteristics, growth, yield and water productivity of okra crop. The experiment was arranged in randomized blocks, with 6 treatments (CHB+BSS -coconut husk biochar + biochar of sewage sludge, CHB+RSS-coconut husk biochar + raw sewage sludge, BSS+RSS -biochar of sewage sludge + raw sewage sludge, CHB -coconut husk biochar, BSS -biochar of sewage sludge, WB -without biochar (control)). Plant height, number of fruits per plant, yield and water use productivity were evaluated. To evaluate the effect of biochar on soil, soil samples weretaken to determine pH, CEC, P, K, Ca, Mg concentrations after incorporation of biochar into the soil. The BSS + RSS and BSS treatments provided better results on okra production and growth characteristics with a 421.15% and 419% productivity increase, respectively, compared to the control treatment. The BSS and BSS + RSS treatments provided better water productivity,with values of 14.5 and 13.3kilogramproduced for each cubic meter of water applied, respectively.All soil chemical characteristics analyzed were modified when the biochar was incorporated into the soil. The results provide valuable insight that okra growers can embrace the use of the combination BSS+RSS and BSS, providing better yields and lower water use in growing this plant.

CHẤT LƯỢNG MÔI TRƯỜNG NƯỚC VÙNG CỬA SÔNG BA LẠT

Ba Lat estuary is the large mouth of the Red river; every year, the Ba Lat estuary receives million cubic meters of water before the water is dissolved in the sea. Therefore, polluted materials in the water from the continent are also transported to the sea through the estuary. However, the volume of the water pouring into the sea varies with the season. In this paper, the water quality at Ba Lat estuary (Red river) was surveyed in July 2017 representing the Southwest wind season (rainy season) and in October 2017 representing the Northeast wind season (dry season). The research results show that the values of chemical parameters of water at Ba Lat estuary changed according to the season: the average temperature of water in the rainy season was 2.5oC higher than in the dry season; average pH in the rainy season (7.45 ± 0.36) was higher than that in the dry season (7.01 ± 0.17). Parameters such as conductivity, salinity, NO3-N, NH3-N, PO4-P, total grease, Fe and Zn in the dry season were 1.22–2.92 times higher than in the rainy season. Concentration of some nutrition (including NO3-N; NH3-N; PO4-P and SiO3-Si), heavy metals (Fe, Zn), and total grease in the water were high, in which NO3-N ranged from 0.565 mg/l to 1.129 mg/l; NH3-N ranged from 0.139 mg/l to 6.16 mg/l, 1.53 to 4.47 times higher than the standard of Vietnam. PO4-P ranged from 0.16 mg/l to 0.82 mg/l, which was 2 to 3.14 times higher than the standard. SiO3-Si ranged from 3.49 mg/l to 5.31 mg/l. Iron concentration in the water was 2.2 to 9.7 times higher than the standard and not different between the two seasons. Zn ranged from 0.64 mg/l to 2.56 mg/l, 1.28 to 5.12 times higher than the standard. Total grease ranged from 2.8 mg/l to 7.0 mg/l, 5.6 to 14 times higher than the standard. Other parameters such as DO, BOD5, Fe, SiO3-Si in the Northeast wind season were 1.01 to 1.35 times lower than in the Southwest wind season. In particular, DO ranged from 3.75 mg/l to 4.99 mg/l, lower than the QCVN 10-MT: 2015 standard and the DO was not suitable for the growth and development of aquatic life. Iron concentration ranged from 2.172 mg/l to 2.209 mg/l, 4.3 to 4.4 times higher than the standard. Water quality also varies with the space, most notably in electrical conductivity, salinity and grease. In particular, the salinity and conductivity tend to increase gradually from the river to the sea, the total oil and grease reached the highest point at BL7 in both phases, and NO3-N in phase 2 reached the highest value at BL6 to BL11.

Water resources allocation in Erhai irrigated district considering catchment water-cycle health

In order to realize the healthy circulation of Erhai Basin water system, this paper constructs the Mike basin simulation model of Erhai Basin water resource system through the concept of water resource comprehensive allocation. Which is based on the principle of Erhai Lake water ecological environment protection and follows the principle of ecological priority, sanitary water into the lake, double control of total amount and consumption, and water conservation and emission reduction. The results show that agriculture irrigated area of Erhai Basin should be gradually reduced to 472000 mu, and 48200 mu of wetland ecological pool should be increased, which is used as the collection area of basin landscape and irrigation return water. After adjusting the crop planting pattern according to the depth of water saving in Erhai irrigation area, the goal of controlling the agricultural water consumption to be no more than 201 million cubic metre and the total water consumption to be less than 366 million cubic metre should be achieved. The effect of reclaimed water irrigation on water saving and emission reduction is considerable. The application of reclaimed water irrigation can reduce the amount of clean water used in paddy growth period by 46.4%, and the amount of nitrogen fertilizer applied by 30.2%. The replacement rate of garlic reclaimed water can reach 100%. After the comprehensive allocation of water resources, it can supply 501 million cubic metre of ecological water in the river channels and 359 million cubic metre of water out of the river channels. Through the comprehensive utilization project of farmland drainage water and the construction of ecological regulation and storage belt, all irrigation drainage water should be reused and zero discharge can be realized. TN and TP emissions in irrigated area will be reduced by 39.3% and 46.3% respectively. Compared with the current situation, Erhai Lake water inflow and cleanly water inflow increased by 65 million cubic metre and 134 million cubic metre respectively. The annual average water level of the lake will be 0.15m higher than the current situation.

Inter-basin water transfer planning with grey COPRAS and fuzzy COPRAS techniques: A case study in Iranian Central Plateau

To overcome water scarcity and increasing water demands, achieving economic and social development, and to make regional equilibrium especially in countries with climate variations such as Iran, the inter-basin water transfer is considered as one of the crisis reduction methods. In this study, the COPRAS method, which is one of the new MCDM methods, is used for the first time to evaluate inter-basin water transfer projects in three configurations of integer, fuzzy, and grey (intervals). For this purpose, eight inter-basin water transfer scenarios from the Great Karoon Basin to the Central Iranian Plateau, are determined with the aim of overcoming drinking water scarcity. They are assessed by four important and practical criteria for inter-basin water transfer, including technical risks and the difficulty of execution, political and social problems, environmental problems, and cost per cubic meter of water according to the UNESCO standards. The weights of the criteria were obtained using three methods of AHP, DEMATEL, and Shannon entropy in the integer, fuzzy, and grey ways. Then, scenarios were prioritized using the COPRAS method. Finally, the results were ranked using the Borda count method, which is a method to aggregate the different ranking models. In this study, the results showed that among the criteria, technical risks, and then the cost per cubic meter of water are the essential criteria, respectively. Considering all ranking methods shows that among the scenarios, the eighth scenario, including water transfer from Behesht-Abad basin to Isfahan province and from Kharsan basin to Yazd and Kerman provinces, is superior to the other scenarios. Final COPRAS value of this scenario varies between 0.155 and 0.194 depending on the applied ranking method, and its total Borda score is 63. The findings of this study can help the decision-makers to evaluate the inter-basin water transfer projects in uncertain conditions.

Neutralization Acid Mine Drainage (AMD) using NaOH at PT. Jorong Barutama Grestone, Tanah Laut, South Borneo

Acid mine drainage (AMD) is mine water with a low pH derived from the oxidation of pyrite containing sulfide with water and air to produce sulfide acid (H2SO4) containing free sulfate. Acid mine drainage treatment carried out at PT Jorong Barutama Greystone Tanah Laut uses limestone at a cost of Rp.220. - per cubic meter of water. This study was conducted to determine the use of technical NaOH for changes in mine acid quality (pH. Fe and Mn). The method carried out by active handling is by adding technical NaOH into mine acid water. The results showed that neutralization of acid mine drainage using technical NaOH 10% to pH 8. was able to reduce Fe by 18.60 - 25.42% and Mn by 31.95 - 39.27%. at a cost of Rp.327. - per meter cubic of water

Water Recovery from Floor Cleaning Operations of Industrial or Public Areas: The Results of a Field Test

Water resources are increasingly under pressure because of human activities and economic development. Moreover, accelerated urbanization and the expansion of drinking water supply and sanitation systems contribute to this rising demand. The development of water reuse solutions is an urgent issue. This study presents a solution for the reuse of wastewaters generated from floor cleaning operations of industrial or public areas. A portable device containing a grid, for coarse filtration, and a 300-L reaction chamber to carry out the sequential processes of coagulation, flocculation and settling, was employed for a field test. In the field test the wastewater coming from the tank of a cleaning machine, used for floor cleaning in an industrial site, was treated and reused for the same purpose for a total of 110 times. The quality of the treated wastewater was monitored cycle after cycle and the results of the test demonstrated that the treated water was suitable to be reused for the same purpose, even after a large number of cycles, provided that a finishing treatment was eventually supplemented in order to reduce the residual concentration of organic substances. It was demonstrated that, under standard operating conditions, that is a wastewater with a total suspended solid (TSS) content of 800 mg/L, and on the grounds of the results found in the test, that is a TSS removal efficiency of 98% and a sludge total solid (TS) content of 6%, the whole volume of the cleaning machine tank was completely renewed with fresh water after 60 cycles. Eventually, the combination of treatment and reuse operations allowed to save approximately 18,000 L of fresh water over a series of 60 cleaning cycles. The proposed treatment allowed not only to save fresh water but even to reduce the cost of water usage by approximately 50%. In fact, thanks to this treatment, the cost of a single cubic meter of water decreased from approximately 6 €/m3, which included supply of fresh water and discharge to the public sewer, to approximately 3 €/m3.

High-speed electron-beam water treatment: A technological consideration

The desired arrangement of the electron accelerator and the reaction vessel for large-scale electron-beam treatment of water at absorbed doses of several kGy is considered from a technological point of view. Each of the accelerators tested earlier showed the potential to irradiate no more than 20 thousand m3 per day, which is many times less than practical needs. At the same time, there are no power restrictions for existing high-voltage generators, which can serve as a key prerequisite for creating high-power accelerators. A model comprising several accelerating tubes powered by one high-voltage generator and a model containing one accelerating tube equipped with several beam windows oriented in different radial directions are compared. Evaluation calculations reveal the possibility of irradiating nearly 200 000 cubic meters of water per day with a single accelerator.

Sustainable optimization of regional agricultural water use by developing a two-level optimization model

The present study applies a two-level optimization model. The first-level objective is to optimize the cropping pattern in the whole grid based on the amount of water consumed per crop. The second-level objective is to maximize the profit and minimize the disruption of water resource sustainability in branch and distributary canals in the district of Qazvin, Iran. Based on the results of the first-level objective, the scenario of a 10% reduction in irrigation water increased economic productivity at various levels by an average of 25 USD per cubic meter of water while maintaining proper income. The second-level results indicated a 64% increase in net profit compared to the profit associated with the existing cropping pattern due to (a) the reduction of crops of low profitability in the cultivated area and (b) the increase of high-profitability crops in the cultivated area. On the other hand, according to the considered objective functions, the amount of water consumed in optimal conditions reduced from 100 of water allocated to 80%.

Energy efficiency of multi-apartment residential houses with individual heat supply

Centralized hot water systems widely used in Russia and Belarus are characterized by a considerable length and branching which inevitably leads to increased heat losses and to an unstable hydraulic system. The operation of the domestic hot water system in the circulation mode can be characterized by several parameters; one of which is the specific ratio of the cost of thermal energy for heating a cubic meter of hot water. The parameter is often regulated by law in Russia; exceeding this parameter is considered as administrative violation. The aim of the research is to determine the design and actual costs of thermal energy for hot water supply (hot water heating) and their comparison, analysis of the data obtained. The methodology for determining the design and real costs of thermal energy for hot water supply was to study the operation of the hot water supply system of a residential 144-apartment 9-storey building. The research showed that the actual circulating flow rate is much less than the calculated circulating flow rate. The authors note that in order to optimize the standard for heating a cubic meter of water it is necessary to observe the calculated circulation modes. This will require stabilization of the hydraulic systems of both the external and internal networks which is a difficult but feasible task. The research results are supposed to be taken into account when setting up existing hot water supply systems.