DOI 10.35776/MNP.2019.10.01
UDC 628.166:661.417/.418

Pchel'nikov I. V., Terikov A. S., Nguen Tkhi Tuan Z’ep, Shchukin S. A.

The study of direct electrolysis of water in the Vietnam Sea
in the production of sodium hypochlorite

Summary

Electrochemical sodium hypochlorite is used at water supply facilities all around the world. The use of natural waters containing chlorides as a raw material is very promising since it greatly simplifies the process flow scheme for producing sodium hypochlorite. Direct electrolysis technology can be retrofitted into the existing water treatment schemes without significant changes. The use of natural water containing chlorides eliminates the purchase of salt which reduces the cost of the finished product. The results of studies of direct electrolysis of water in the Vietnam Sea are presented. During the experiments the effect of seawater flow rate and current density on the concentration of active chlorine in the resulting sodium hypochlorite, the change in the current chlorine yield and the specific energy consumption per 1 kg of generated active chlorine were determined. The main process parameters are determined that provide for producing sodium hypochlorite by direct electrolysis of sea water using an iridium-ruthenium oxide titanium anode as electrodes. It was shown that the current chlorine yield reaches maximum values (85–90%) at an active chlorine concentration in the product of 2 ± 0.2 g/dm3 which motivate the technological and economic feasibility of obtaining sodium hypochlorite from sea (ocean) water.

Key words

sodium hypochlorite , chlorides , sea water , direct water electrolysis , current density

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DOI 10.35776/MNP.2019.10.02
UDC 628.166.085:524.3-74

Piskareva V. M., Kupin K. V.

The experience of using UV disinfection in the biggest European cities

Summary

The technology of drinking water disinfection by ultraviolet radiation has been widely used abroad. An example of the successful operation of UV-units is water treatment plants in Europe where various process flow schemes of UV disinfection have been implemented: as part of a multi-barrier scheme and as an independent method. The results of the introduction of UV technology at water treatment plants in Budapest (Hungary), Vienna (Austria), Berlin (Germany), Antwerp (Belgium) are presented. When preparing drinking water from surface sources it is recommended to use multi-barrier schemes including disinfection methods that ensure a prolonged effect. The effectiveness of UV disinfection in relation to viruses and protozoan cysts provides for reducing the dosage of chlorine-containing chemicals which inhibits the formation of chlororganic compounds. The decision to abandon chlorination while using UV-disinfection as an independent method should be substantiated considering the actual operating conditions of the water treatment facilities and water distribution networks.

Key words

potable water , ultraviolet , water treatment , UV disinfection

DOI 10.35776/MNP.2019.10.03
UDC 628.1/.3:303.6

Pukemo M. M., Pupyrev E. I.

Information security of the water supply and sanitation utilities as in the case of the Baikal natural area (in order of discussion)

Summary

A new concept for wastewater metering and charging for the sanitation services for the Russian Federation is considered. Introducing multilevel digital control of water consumption and sanitation services rendered to the customers, operating companies and treatment facilities in order to reduce the ecological risks and environmental damage from illegal wastewater disposal by the customers is proposed. A new mechanism for collecting and consolidating information data from water supply and sanitation facilities has been developed that provides for implementing the concept of sustainable water use, improving the quality of service of sanitation systems, reducing the operating costs and failure rate. It is proposed to introduce a number of amendments in regional legislation related to charging for water consumption and sanitation services.

Key words

treatment facilities , wastewater treatment , water supply-sewerage services , computerization , environmental risks , Lake Baikal , central ecological zone , information security

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DOI 10.35776/MNP.2019.10.04
УДК 614.844

Yepifanov S. P., Zorkaltsev V. I., Baranchikova N. I., Korel’stein L. B.

Hydraulic calculation of automatic firefighting systems
combined with internal fire water pipeline system

Summary

In recent decades the construction of large buildings has risen sharply: shopping and entertainment centers, multifunctional high-rise buildings for residential and public purposes with underground parking lots, storage facilities for the storage of combustible materials. During construction finishing materials are often used that emit toxic substances if ignition occurs. Fires can result in fatalities and substantial material losses. For the fire safety of buildings and structures the use of firefighting water supply – both outdoor and internal is most effective. Due to the inability to provide for outdoor firefighting of a large part of the premises of the upper floors of high-rise buildings, the effectiveness and reliability of internal firefighting systems is of particular importance. Water consumption for fire water supply can be 200 l/s or more. To supply water in such a volume to the fire points, effective internal fire water supply systems are required: automatic firefighting systems (sprinkler and deluge), internal fire water pipelines, deluge water curtains. Combined internal firefighting systems include automatic firefighting installations and internal firefighting water pipeline. The method of hydraulic calculation of each of these systems is available in the regulatory and specialized literature. However, in the process of hydraulic calculations of combined (integrated) firefighting water supply systems, their essential features should be taken into account. In this regard, a mathematical model of flow distribution in automatic firefighting systems combined with an internal fire water pipeline system is considered. The technique of hydraulic calculation of arbitrary combined firefighting water supply systems is given. The proposed model allows you to get an actual value of water abstraction through nozzles (sprayers) and hand control branch pipes.

Key words

pressure , head , hydraulic design , water curtain , automatic firefighting installations , internal fire water pipeline , flow distribution task , variable abstraction

DOI 10.35776/MNP.2019.10.05
UDC 614.842.62:378.187

Chibinev N. N., Seredina A. V., Pashkova I. A.

Improving internal fire water supply systems in student dormitories

Summary

The need of conducting an expertise of the internal fire water supply systems in old buildings of student dormitories in accordance with the requirements of paragraphs 55 and 57 of the «Rules of the fire safety arrangements in the Russian Federation» is substantiated. Cases of inefficient use of the internal water supply system in such buildings in the event of a fire are considered. Based on the study of the internal fire water supply system of a dormitory building in order to improve similar systems, the following is proposed: to carry out a test calculation of the operating systems no less than the service life specified in the passport of the manufacturer of the boosting pump; for quick suppression of a possible fire (before the formation of critical parameters of fire hazards) the boosting pumps should be activated not by the remote start buttons but by the automatic fire alarm system with its start duplicating by the start button in the clock at the security desk of the dormitory; for the effective use of internal fire water supply systems with the simultaneous evacuation of students the boxes of fire hydrants should be equipped with filter self-rescuers (at least three).

Key words

student dormitory , fire , required head , pump characteristic , automatic fire alarm , firefighting water line

DOI 10.35776/MNP.2019.10.07
UDC 628:004.413.4

Grachev Vladimir, Kurysheva N. I., Plyamina O. V., Lobkovskiy V. A., NEFEDOVA E. D.

Algorithm for assessing the degree of physical deterioration
of structurally complex water supply and sanitation facilities
using a risk-oriented approach

Summary

The paper analyzes current regulatory documents and experience in the field of assessing the deterioration of structurally complex water supply and sanitation facilities. The paper shows that modern assessment procedures do not take into account any features of such objects. The paper identifies factors that affect the indicator framework for assessing the physical deterioration of the main groups and components of water supply and sanitation facilities. Based on these factors, the paper proposes an algorithm for assessing the physical deterioration of facilities using a risk-oriented approach for three levels: an object itself, its engineering components (facilities), and their functional elements (buildings, equipment). The paper indicates that the use of the algorithm would provide for developing recommendations for adjusting the frequency of monitoring indicators of the physical deterioration level of facilities of public water supply and sanitation systems and their elements. The implementation of the developed algorithm would contribute to the successful introduction of advanced approaches to managing risks associated with the level of physical deterioration and assessing the probability of potential negative consequences of natural, anthropogenic, and other origins. The introduction of the algorithm would also allow identifying vulnerable areas and taking preventive measures against the threat of violation of mandatory requirements including measures for reducing risks (technical and engineering renovation of buildings, facilities, equipment). This is required for objective and substantiated planning of overhaul, restoration, and development of water supply and sanitation facilities and their components.

Key words

water supply-sewerage services , risk-oriented approach , physical deterioration , integrity health , algorithm of assessment

DOI 10.35776/MNP.2019.10.06
UDC 628.355

Kevbrina M. V., Akmentina A. V., Dorofeev A. G., Agarev Anton, Aseyeva V. G., KOZLOV M. N., Nikolaev Yu. A.

Advanced technology of municipal wastewater treatment
with granular sludge

Summary

Increasing the specific biochemical capacity of the facilities using the so-called granular activated sludge is one of the promising areas for the development of biological wastewater treatment technologies. Granular sludge is microbial biocenosis specializing in the decomposition and mineralization of substances present in wastewater. The main distinction from regular sludge is due to two important factors: the composition of the basic structural unit of granular sludge – granules, and a high sedimentation rate (up to 20 m/h). This provides for developing sludge doses of up to 10 g/l in bioreactors of wastewater treatment. The results of the development of the first biotechnology in Russia for municipal wastewater treatment of using granular activated sludge are presented. The technology has been implemented at the facilities of Mosvodokanal JSC. The technology of aerobic biological treatment in a sequencing batch reactor with sequential nitri-denitrification and an upward flow of wastewater provides for the quality of effluent that meets the standards for maximum permissible concentrations for discharge into fishery bodies. Technical and economic comparison of the developed technology with the technology of removing nutrients in flow-through aeration tank showed that the life cycle costs of the facilities with partially granulated activated sludge are 1.4 times less than the costs of traditional biological treatment technology (for a capacity of 1000 m³/day).

Key words

biological treatment , granulated activated sludge , municipal wastewater , nutrients removal , SBR-reactor

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DOI 10.35776/MNP.2019.10.08
UDC 628.356.1:621.61

Iadrishchenskii A. N., Filippova N. N., Bulygin K. A., Kolobova G. I., Gordeichik A. V., Usachev A. P.

Reconstruction of the air blower station at the wastewater treatment facilities in Chita

Summary

The results of the reconstruction of the wastewater treatment facilities in the city of Chita are presented with regard to the system of supplying air to the operating sections of the aeration tanks without replacing the air blower units. The main goal of the reconstruction was energy saving and automation of air supply to the aeration tanks while ensuring sufficient oxygen concentrations in the wastewater biological treatment facilities. To change the capacity of the air blowers the automation system includes two high-voltage frequency converters for the number of blowers in operation. To regulate the air supply eight regulated valves and eight dissolved oxygen sensors (for the number of operating sections) are installed in the sections of the aeration tanks. Energy savings over four months of operation amounted to about 16.4% compared to the same period of previous years.

Key words

frequency converter , sewerage treatment facilities , aeration tank , controllable air blower station , variable-frequency control of blowers

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DOI 10.35776/MNP.2019.10.09
UDC 628.3:62-278

Kofman V. Ya.

Micromotors – a recent trend in developing water and wastewater treatment technologies (a review)

Summary

Micromotors are autonomous, performing certain functions, self-propelled microdevices based on inorganic, organic or biological materials. Implemented in a micromotor design are two functions: autonomous movement and effective capture and/or destruction of various chemicals, including pollutants. To ensure autonomous movement the micromotor device provides for the creation of local thermal, acoustic, chemical gradients arising from asymmetric morphology or surface structure. The movement is provided through the use of various energy sources including light, electric and magnetic fields, ultrasonic waves or chemical “fuel”. The chaotic trajectory of micromotors throughout the solution provides for the highly efficient interaction of the chemicals immobilized on their surface with the targeted pollutants or detectable substances. The most elaborated principle of creating autonomous movement is the generation of a recoil impulse at asymmetric formation of gas microbubbles as a result of a chemical reaction. Currently, the main studies on the use of micromotors in water purification processes are carried out in the areas of analysis of aqueous media, removal of heavy metals, organic pollutants, dyes and oil products, as well as water disinfection. It is estimated that micromotors possess unique capabilities in the field of detection and removal of pollutants in aqueous media due to a combination of adsorption and catalytic properties with autonomous movement.

Key words

disinfection , adsorption , water and wastewater treatment , micromotors , autonomous movement , catalysis , removal of pollutants