UDC 628.16:574.58
DOI 10.35776/VST.2025.06.01

Ksenofontov Boris, Tiumentseva Mariia, Serov Sergei

Natural water purification using Chlorella microalgae

Summary

The results of studying the process of bioremediation of natural water using Chlorella microalgae, including mechanisms of pollution absorption, optimal conditions for microalgae culturing, and an estimation of the impact of purified water on the environment are presented. The purpose of this study is investigating the effect of different doses of Chlorella suspension on the removal of nitrogen, ammonia, and turbidity reduction in natural water. The experiment was carried out using Chlorella vulgaris microalgae culture with a concentration of 1.5 g/l. Natural water taken from the Iauza River was used as the test sample. During the 21-day experiment, a constant temperature of 25 °C and continuous illumination of 5000 lux were maintained. A turbidity meter HACH 2100N was used to determine the water turbidity. Concentrations of nutrients were determined using NKV-1 field laboratory for water analysis. The experimental study showed that the sample with 0.3 g/l Chlorella dose provided for the best results in terms of water quality: the nitrite concentration decreased to a minimum value of 0.01 mg/l, the nitrate concentration reached a minimum value of 0.001 mg/l (corresponding to the lower limit of sensitivity of the test method), the turbidity decreased from 2.61 to 0.58 mg/l.

Key words

turbidity , natural water , nutrients removal , Chlorella microalgae

UDC 628.221
DOI 10.35776/VST.2025.06.02

Volkov Sergei, Luk’ianchuk Maksim, Zhukova Anastasiia, Solokhin Anton, Kuz’min Valentin, Zhitenev A. I., Rublevskaya O. N., Gvozdev V. A., Erofeev Vasilii, Kostenko I. G., IGNATCHIK V. S., Ignatchik S. Iu., Kuznetsova N. V., Seniukovich Mikhail, Eshchenko Andrei

Justification of the optimum alternative of the wastewater disposal system of St. Petersburg adapting to the conditions of the joint effectof urbanization and climate change
Part 4. Justification of the type of model for the management
of a wastewater disposal system

Summary

As follows from the economic comparison, the optimal option for adapting the wastewater disposal system to the conditions of the combined impact of urbanization and climate change St. Petersburg is a combination of «gray» technologies and an automated control system (ACS). Elements of «gray» technologies, in particular, include the construction of intermediate storage tanks and flow redistribution nodes between basins. An ACS with intermediate storage tanks and water outlets control in real time (Real Time Control, RTC) is a proven approach to reducing flooding and raw wastewater spills. The method for developing RTC strategies involves two main stages. The first stage is defining controlled sub-basins equipped with control points and spill points. At the second stage, the data of these subsystems (sub-basins) and their interrelations are used to develop control algorithms. For subjective and objective reasons implementing this approach in the conditions of the Russian Federation and St. Petersburg is virtually impossible. One way out of this situation is using artificial neural networks as a control model that can provide for the speed of analysis, generalization ability and high fault tolerance required for the effective implementation.

Key words

surface runoff disposal system , flooding , adaptation measures , automated wastewater management system

UDC 628.52
DOI 10.35776/VST.2025.06.03

Orlov V. А., Primin Oleg

Analysis and criteria of using degassing methods in wastewater disposal systems (a review)

Summary

An analysis of international and Russian scientific studies related to preventing anaerobic conditions in sewer networks by taking operational and construction measures was conducted. A list of alternative methods for the effective suppression and elimination of malodors from foul-smelling volatile pollutants (hydrogen sulfide, ammonia, phenol, formaldehyde, etc.) emitted from point sources such as wastewater treatment facilities, pumping stations, ventilation hoods of canals and sewers is presented. The aspects of effective blocking of gas formation processes and reduction of gas spreading in the gas sphere by various methods, including physical-chemical, construction, etc., are considered in order to prevent aggressive gases from escaping to the daylight surface.

Key words

wastewater , gas cleaning , malodorous aggressive gases , preventing and fighting odor , optimization of technical solutions

UDC 628.2: 532.5
DOI 10.35776/VST.2025.06.04

Chupin R. V., Bober Viktor

Structural redundancy of public wastewater disposal systems

Summary

Traditionally, wastewater disposal systems have a branched tree-like structure thatprovides for the efficiency of collecting and transporting wastewater to the wastewater treatment facilities. Along with that, blockage of any section of the network or its emergency shutdown leads to wastewater spills that singinficantly affect the environment. During routine network repairs wastewater pumping into other operating collectors located in neighboring areas or downstream is provided. However, in case of sudden failures these measures often cannot be provided in spot. Methods of structural reservation of network sections by providing parallel and ringed (discharge) sewers with subsequent estimation of their reliability are proposed. The estimation is based on simulating the modes of wastewater flow and possible spills from inspection wells. The reliability is estimated by the annual volume of wastewater spills resulting from emergency shutdowns of network sections. The effectiveness of structural reservation by ringing gravity sewers is studied.

Key words

wastewater disposal system reliability , redundancy by parallel sewer laying and ringing , calculation of flow distribution in ringed wastewater disposal systems

UDC 628.112
DOI 10.35776/VST.2025.06.05

Kosteuk Aleksandr

Reliability of borehole pumping units: causes of failure and methods of their elimination

Summary

The most common causes of borehole pump failures and methods for eliminating them both at the stage of pump selection and during operation are considered. A significant number of pump failures are associated with incorrect selection of pumps for operating conditions, in particular, selecting pumps with characteristics that do not meet the system requirements resulting in the pump operating beyond the operating range. Examples of the most common errors in pump selection and their consequences are given. Monitoring the pump operating mode, in particular, monitoring the position of the operating point relative to the operating range provides for identifying the problem. Pump parameters are monitored both by direct methods by measuring the parameters, and indirectly. If the pump operating point is beyond the operating range, taking corrective actions aimed at remediating the situation is required. Following the proposed recommendations will help the staff operating pumping equipment to analyze the causes of borehole pump failures and develop corrective measures.

Key words

reliability , well pump , pump characteristic , pump operating range , pump control

FESENKO L. N.

XVI «TECHNOVOD–2025» International Scientific and Practical Conference

Summary

22–25 апреля 2025 г. «ТЕХНОВОД–2025» вновь собрал участников конференции в столице Татарстана – городе Казани. И это не случайно. «ТЕХНОВОД–2005», второй по счету научно-практический форум, также состоялся в Казани в дни празднования 1000-летия этого прекрасного города на берегах великой русской реки – Волги.

UDC 628.112.2
DOI 10.35776/VST.2025.06.06

Ivashechkin V. V., Medvedeva Iu. A., Artemchik Aleksandr

Water well hydraulic elevator with a washing nozzle

Summary

The process flow scheme of removing sand plugs from water wells using a well hydraulic elevator is considered. According to the scheme, water from a pressure tank is supplied by a duty high-pressure pump via the feed pipeline simultaneously to the washing nozzle and active nozzle of a jet pump equipped with a feed pipeline for removing the generated pulp from the well. The values ​​of water flow out of the nozzle and washing nozzle were determined by the graphical-analytical method. The flow rate of the pulp injected into the mixing chamber and the geometric dimensions of the jet pump were determined by the momentum equation. The method of calculation and selection of parameters for the process equipment of the water well hydraulic elevator with a washout nozzle are presented. The method of calculation of the water well hydraulic elevator with a built-in washing nozzle has been developed that provides for selecting a duty pump and calculating the geometric dimensions of the hydraulic elevator depending on the well depth and static water level. An example of calculation is given.

Key words

water well , sanding up , waterjet pump , sand plug , washing nozzle , water well hydraulic elevator

UDC 628.336.3
DOI 10.35776/VST.2025.06.07

Sinegubov Sergei, Daineko Fedor, Dzhumagulova N. T.

Developing process engineering solutions for wastewater sludge dewatering

Summary

A process flow scheme for wastewater sludge dewatering has been proposed that formed the basis for the project of retrofitting sludge processing facilities at the Tula wastewater treatment facilities. The introduction of methods and technologies for mechanical sludge dewatering has replaced sludge beds. In the process of selecting the main process equipment for the sludge dewatering plant of the Tula treatment facilities, a belt filter press was chosen. The construction of the sludge dewatering plant at the treatment facilities will provide for reducing the amount of sludge, pollution emissions into the atmosphere, and payments for emission. Significant land vacation and recoverability is provided. The results of calculating the amount of waste generated after the retrofitting the sludge dewatering plant are presented, and payments for pollution emissions from sludge beds are calculated. A comparative analysis of the economic and environmental indicators of the planned and existing measures for handling wastewater sludge is carried out.

Key words

treatment facilities , filter-press , sludge dewatering , environmental protection , wastewater sludges , sludge beds