Tag:biological treatment

№10|2015

AUTOMATED AND INFORMATION MANAGEMENT SYSTEMS

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UDC 628.2/.3:658.52.011.56

Regotun A. A., Daineko O. N., Smirnov Aleksandr Vladimirovich

Automated control of the treatment facilities on the basis of mathematical models

Summary

The applicability of the mathematical models in the control of wastewater treatment facilities in terms of the operational issues solutions is considered. A possible option of using the software package on the basis of ASM mathematical models in the control of the biological treatment plant with retrofitting into the control system of the entire wastewater treatment facilities is presented. The gene­ral principles of control system building with the integrated mathematical model of the biological treatment process are described. The comparative analysis of the popular advanced software simulation packages and the simulation software developed by My Project Company is sited. By the example of the standard aeration tank configuration the possible and easy integration of the software into practically any advanced SCADA-system is demonstrated. The contrary case is described: the use of the software in the highest level of the automated process control system of the wastewater biological treatment.

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№9|2019

WASTEWATER TREATMENT

DOI 10.35776/MNP.2019.09.07
UDC 628.356

Bazhenov V. I., Ustiuzhanin A. V., Koroleva Ekaterina

Aeration for wastewater biological treatment: updating foreign terms and abbreviations

Summary

The study of domestic and foreign methods for aeration tanks evaluation and their design guidelines is presented. The analysis of modern approaches to the calculation of treatment facilities indicates that the calculated air flow rate is determined in accordance with the oxygen demand of the biological process for the oxidation of organic compounds, nitrification and denitrification. International terms and abbreviations have been adapted to Russian analogues taken in conjunction with the theory of oxygen mass transfer, as well as the international guidelines for the design of wastewater treatment facilities. The difference between the field (experimentally measured) and calculated (determined for the design) parameters OUR and AOR, SOTR and SOR is explained. Balance equality between OTR and AOR is an optimal and economical design solution. It is noted that the use of updated international terms and abbreviations in tender and competitive procedures (during design and delivery) will simplify their implementation and ensure mutual understanding between the parties. The need for regulation of the air supply to aeration tanks is justified by the balance of oxygen «consumption – transfer». In dynamic conditions for regulated systems OTR → OUR. With the automated maintenance of the set point for the concentration of dissolved oxygen this condition provides for the savings in energy consumption.

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№12|2020

WASTEWATER TREATMENT

UDC 579.695+579.8

Gogina Elena, Bazhenov V. I., Sokolova Kseniia

Bacterial composition of activated sludge: identification and visualization

Summary

The objective of this work is to describe the capabilities of a method for visualizing activated sludge bacteria based on the information from an Internet resource for developing textbooks and/or manuals. Advanced methods of microscopy of the bacterial community are considered: optical light, scanning electron (SEM), transmission electron (TEM), confocal (CLSM), fluorescence hybridization in situ (FISH), new generation sequencing (NGS). On the basis of the methods presented, examples of bacterial flocculation of activated sludge with extracellular and reserve biopolymers are given. According to the highest citation frequency in professional reference books and literature, a sample of the most typical bacteria from the composition of floccules of activated sludge was compiled. Examples of visualization of four bacteria by SEM, TEM, KLSM, FISH methods are given: Bacillus subtilis (gram-positive, spore-forming, optionally aerobic), Nitrospira defluvii (gram-negative, aerobic, chemolithotrophic, nitrite-oxidizing), Candidatus «Accumulibacter phosphatis» (gram-negative, phosphate-accumulating), Candidatus «Microthrix parvicella» (gram-positive, filamentous, actinomycete). To date, the Internet resource contains a sufficient amount of reliable data on the visualization of activated sludge bacteria, their functionality and properties related to the key processes of biological treatment, classification or taxonomy, as well as on the methods of their microscopic study. The implementation of the capabilities for identifying the bacterial composition of activated sludge and the quantitative ratio of heterotrophic, autotrophic and phosphate-accumulating biomasses provides for setting and/or calibrating models of ASM series (for example, in GPS-X, BioWin, etc. software environment).

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№10|2011

WASTEWATER TREATMENT

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UDC 628.355.2

Nikolaev Yu. A., KAZAKOVA E. A., GRACHEV V. A., Kevbrina M. V., Dorofeev A. G., Aseyeva V. G., Akmentina A. V.

Biological treatment of municipal wastewater and return flows with the use of granulated sludge

Summary

The experience of aerobic granulated activated sludge formation in the laboratory batch reactor by sedimentation selection with the use of flocculant is described. The sludge is used in the process of low concentrated municipal wastewater and sludge dewatering filtrate (centrate) treatment. The developed technologies of granulated sludge formation provide for the intensification of the wastewater treatment processes; and hence the reduction of the treatment facilities footprint is ensured alongside with the improvement of their operation, reliability and efficient performance.

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№12|2016

WASTEWATER TREATMENT

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UDC 628.31:661.5

MOROZOVA K. M., Stepanov S. V., Stepanov A. S., Sokolova T. V., Solkina O. S., Zhukova M. A.

Biological treatment of dairy industry wastewater in a membrane bioreactor (part 1)

Summary

The results of research study in the field of biological treatment of dairy wastewater are presented. The studies carried out under contact conditions showed that the kinetics of oxidation of dairy wastewater pollutants with activated sludge can be described by enzymatic reactions equation for substrate inhibition; at that, the obtained inhibition constants point at the increase of the wastewater toxicity after chemical flotation for biological treatment processes. The technology has been proved with simulative effluent in a pilot membrane bioreactor. The kinetic dependences of organics oxidation by BODfull, nitrification and denitrification were determined. The increase of oxidation capacity of the facilities by 1.46 at the sludge concentration increase from 4 to 10 g/l is shown that allows reducing significantly the size of the biological treatment facilities when using MBR technology. In the course of experimental studies at MBR plant and kinetic experiments under contact conditions the coefficients of inhibition with activated sludge metabolism products were determined for the simulative solution of wastewater by BODfull, for nitrification and denitrification. The temperature constant value for aerobic heterotrophic conversion, for nitrification and denitrification processes has been found.

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№2|2017

WASTEWATER TREATMENT

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UDC 628.31:661.5

MOROZOVA K. M., Stepanov S. V., Stepanov A. S., Sokolova T. V., Solkina O. S., Zhukova M. A.

Biological treatment of dairy industry wastewater in a membrane bioreactor
(part 2)

Summary

The technology of biological treatment of dairy wastewater is described that provides for meeting the standard maximum permissible concentrations for fishery water bodies. The results of the experimental studies in a pilot membrane bioreactor with real wastewater of «Pestravskii» butter factory are presented. The main process and kinetic parameters of the biological wastewater treatment processes have been obtained that are needed for designing a membrane bioreactor with nitrification-denitrification that provides for meeting the standard maximum permissible concentrations for fishery water bodies or requirements to the effluents discharged into a public sewer. The maximum specific rate of diary wastewater pollutants oxidation Vmax at 7 g/l activated sludge concentration and 20 °С temperature is 40 mg/(g·h), Michaelis constant Km – 15 mg/l, inhibition coefficient of metabolism products  – 0.54 l/g, temperature constant X for aerobic heterotrophic conversion – 0.079 deg–1. Compared to the traditional treatment facilities the use of biomembrane techno­logy at the wastewater biological treatment stage provides for 1.4–1.5 reducing the treatment time, reactor volume and footprint owing to the increase of the oxidation capacity of the aeration units by increasing the activated sludge concentration to 10 g/l; and ensuring almost complete removal of suspended solids by eliminating the tertiary treatment stage. Possible elimination of chemical flotation stage before biological treatment is shown that provides for reducing the expenditures for expensive chemicals and streamlining the process flow scheme.

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№8|2013

WASTEWATER TREATMENT

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UDC 628.35:661.5

Zoubov M. G., Boyarenev S. F., Zoubov G. M., Koulikov N. I., Shramov Yu. M., Litty Yu. V., Nekrasova V. K., Nozhevnikova A. N.

Wastewater treatment biotechnology with activated sludge immobilization and nitrogen removal

Summary

The data on the development and introduction of advanced wastewater treatment biotechnology with activated sludge immobilization and nitrogen removal with the use of Anammox bacteria are presented. On the basis of laboratory studies and pilot tests full-scale wastewater treatment facilities have been designed. Their operation provides for the high economic, environmental and social effect.

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№3|2022

WASTEWATER TREATMENT

DOI 10.35776/VST.2022.03.05
UDC 628.355

Kevbrina M. V., Gavrilov Dmitrii, Belov N. A., Agarev Anton

The effect of the operation of secondary settling tanks on the efficiency of biological removal of nitrogen through the example of Kuryanovskie wastewater treatment facilities

Summary

«Mosvodokanal» JSC conducted an industrial-scale experiment with the secondary settling tanks of the new section of the Kuryanovskie wastewater treatment facilities in Moscow in order to determine the effect of the operation of settling tanks on the efficiency of biological removal of nitrites. With an increase in the level of sludge stand in the secondary settling tanks, conditions arise in the sludge layer at the bottom of the settler for the anaerobic processes that cause the lysis of activated sludge cells. Under these conditions, a sufficient amount of organic matter is generated in the sludge layer, both residual, occluded on sludge flocks, and formed during the lysis of part of the cells, so that in the presence of nitrates, the process of incomplete denitrification starts with the formation of nitrites. The occurrence of anaerobic processes in the bottom sludge layer in the secondary settling tanks is also affected by the oxygen concentration in the mixed liquor entering the secondary settling tanks. The process parameters of the operation of the facilities that prevent a decrease in the quality of effluent are determined: regulating the operation of secondary settling tanks depending on the load and residence time of the sludge dry matter that prevents the sludge from long staying in the bottom layer, as well as maintaining a high oxygen concentration at the end part of the aeration tanks.

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№4|2017

WASTEWATER TREATMENT

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UDC 628.31:661.5

Stepanov S. V., Solkina O. S., MOROZOVA K. M., Stepanov A. S., Zhukova M. A.

The effect of membrane chemical washing on biological treatment processes

Summary

The results of research studies in the field of biomembrane treatment of dairy wastewater are presented. The experimental studies were carried out during four months. As a model effluent milk solution was used with addition of nutrients in the form of mineral salts – potassium monophosphate, ammonium chloride and sodium nitrate in ratios corresponding to the concentrations of these substances in original wastewater after physical and chemical treatment. The experiment was aiming at determining the process and kinetic cha­racteristics of biological processes in a membrane bioreactor. The studies of the model wastewater in a pilot bioreactor showed that at 7–9 g/l sludge dosage and 0.36 m3/(m2·day) specific flow rate corresponding to the regular operation mode of flat-frame membranes the operation of the plant without chemical washing was possible for about two months. It was stated that membrane washing with citric acid at 1000 mg/l solution concentration (5–20 mg/l acid concentration in the membrane tank) provided for reducing the rate of biochemical processes with only mixed liquor acidification. The citric acid toxicity did not appear at mixed liquor pH in the range of 6.83–7.17. The study of membrane washing with sodium hypochlorite solution in concentration of 2000 mg/l as NaOCl showed the competitive inhibition of the organics oxidation rate with practically complete inhibition of biochemical processes at the active chlorine concentration in the reactor more than 26.1 mg/l. The time of restoring the original rate of organics oxidation at 6.6 mg/l active chlorine concentration in the reactor was 220 minutes after wastewater supply had been started and permeate had been removed.

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№10|2012

WASTEWATER TREATMENT

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UDC 628.35:661.5.63

KAZAKOVA E. A., Streltsov S. A., Kevbrina M. V., Kozlov I. M., Moizhes S. I.

Introducing advanced nutrient removal technologies at the Moscow wastewater treatment facilities

Summary

The results of introducing energy efficient process designs of biological nutrient removal from low concentrated municipal wastewater are presented. At 22–25 mg/l ammonia nitrogen and 2.3–2.5 mg/l phosphate-phosphorus concentrations in the incoming wastewater the stable phosphorus removal was obtained when using the process design of the Cape Town University (UCT). At higher concentrations of wastewater (30–40 mg/l ammonia nitrogen and 3.3–4 mg/l phosphate-phosphorus) the process design of the Hanover University (MISAH) and the modified UCT process design developed by Mosvodokanal MPUE research workers were most efficient.

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№3|2019

WASTEWATER TREATMENT

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UDC 628.356.5

Kevbrina M. V., KOZLOV M. N., Dorofeev A. G.

Secondary settlers: comparison of the calculation methods in designing and analysis of the parameters of efficient operation of the facilities

Summary

The results of the comparison of methods of calculating secondary settlers through the example of a model wastewater treatment plant (domestic method according to SNiP 2.04.03-85, German method according to Germany Standard ATV-DVWK-A131E, American method based on mass flow theory) are presented. It is shown that the surface area of settlers calculated according to Standard ATV has higher values compared to the calculations according to SNiP 2.04.03-85 and American method. The values of the surface area of settling tanks calculated according to SNiP 2.04.03-85 and American method are very close. At the same time the SNiP method is much simpler and requires much less initial parameters than the American method. For the domestic practice of operating secondary settlers it is proposed to introduce a new parameter – «dry matter loading on the settler surface» taken from the mass flow theory. This indicator indicates how much dry matter of the mixed liquor from aeration tanks enters per unit surface of secondary settlers per hour and corresponds to the incoming mass flow. By varying the dry matter loading on the surface of secondary settlers it is possible to provide for the standard suspended solids concentration in effluent. Through the example of the operating 54 m diameter settlers the dependence of the clarification efficiency on this parameter is shown.

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№1|2020

WASTEWATER TREATMENT

DOI 10.35776/MNP.2020.01.03
UDC 628.355

Zalyotova N. A., Zalyotov S. V.

The study of the response of dehydrogenase activity
of sludge to a change in the process parameters of an aeration tank

Summary

The biological method of wastewater treatment is a comprehensive multicomponent process; the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far; however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.

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№10-2|2010

WASTEWATER TREATMENT

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UDC 628.356.57.001.5

SHVETSOV V. N., MOROZOVA K. M., Smirnova I. I., Semenov Mikhail, Lezhnev M. L., Ryzhakov G. G., Gubaydullin T. M.

The Use of Bioblocks at Wastewater Treatment Facilities

Summary

Results of the laboratory study of an aeration tank operation for the purpose of technological comparison of two new modified bioblocks, BBZ-45P-14 and BBZ-65P-10, having the similar surface structure but different geometric parameters are presented. It is shown that these bioblocks can be used successfully in aeration tanks for immobilization of microorganisms of activated sludge. The tests of loading material samples have been carried out at biomass density in bioblocks of 0,3–0,36 kg/kg, at equivalent concentration of sludge in the system – 2,3 g/l. The bioblock BBZ-65P-10 is used preferably in aeration tanks, BBZ-45P-14 – in aeration tanks with low load on activated sludge, blocks of aftertreatment for additional clarification of water treated biologically and in biofilters for build-up of biological film. The comparison of results of tests on rate of activated sludge adhesion obtained with new types of bioblocks and BBZ-65 tested earlier makes it possible to conclude that the adhesion process goes off more intensively on rougher surfaces of modified models of bioblocks.

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№2|2014

WASTEWATER TREATMENT

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UDC 628.35.004.4

Noskova I. A., Bazhenov V. I., Epov A. N.

The use of simulation modeling packages for wastewater treatment technologies

Summary

The subjects of the study were: comparative analysis of software packages for simulation modeling of wastewater treatment processes to manage design and operation issues; and also assessment of basic data for the formation of mathematical model inputs. The basic parameters of the description of the most complicated ASM activated sludge models have been analyzed. The results of the studies are represented by the analysis of the examples: distribution of COD fractions under local conditions of Russia and some other countries; typical irregularity of wastewater flow and basic pollutants hourly input; design and measured oxygen uptake rate (OUR); model time calibration process, optimization of the denit­rification zone in aeration tank for MUCT process. The analysis of the advanced software defined GPS-X (Hydromantis, Canada) design software as the most complete and comprehensive product. The suggested technique includes a set of measures: determining COD fractionation with the use of OxiTop (WTW, Germany) analyzer; assessment of basic parameters of irregular basic pollution mass input; respirometry studies; statistic processing of data obtained at the facilities. In the process of simulation modeling the hydrodynamic structure of the wastewater treatment facilities appears as series-connected mixer chambers. The number of chambers is assigned depending on the length and width of the facility, flow velocity, mixing rate, availability of internal baffles, and also inner recycle streams. The simulation model provides for the optimization of the following parameters: zone ratio in the aeration tank, sludge age, dissolved oxygen concentration, recycle ratio values, as well as the parameters of the automatic control system.

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№10|2020

LAWS, STANDARDS, NORMATIVES

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UDC 628.2/.4:006.35

Kharkina O. V.

The use of methods for calculating biological wastewater treatment facilities (for discussion)

Summary

Current requirements to the quality of effluent of wastewater treatment facilities call for introducing nitrification, denitrification, and phosphorus removal processes into the biological wastewater treatment, in addition to aerobic oxidation of organic compounds. The impossibility of ensuring the quality of effluents to be discharged into fishery water bodies in terms of nutrients MPCs values ​​is explained by the incorrect solutions designed for the introduction of biological wastewater treatment processes, and incorrect approaches to the design of facilities. The section «Wastewater disposal and treatment» of the Expert and Technological Council of the Russian Water Supply and Wastewater Association receives a lot of questions from water professionals interested in the methods of calculating wastewater treatment facilities and, primarily, biological treatment facilities. In this regard, the section «Wastewater disposal and treatment» of ETC RAWW develops Recommendations on the use of methods for calculating wastewater treatment facilities. This document, though not mandatory for execution, will contain information reflecting the viewpoints of the research workers, engineers, technologists, designers and experts in the operation of wastewater treatment facilities, members of the section. The Recommendations will include the results of calculations performed according to various methods and models, as well as conclusions indicating the possibility or impossibility of using certain calculation methods, as well as their limitations and correctness. It is planned to publish by parts the information on various calculation methods, techniques, approaches to calculations, as well as documents containing one or another approach to the design of wastewater treatment facilities is prescribed. After the analysis has been carried out, the consolidated material will be published in the form of Recommendations. This paper presents an analysis of the information contained in SP 32.13330.2018 on the calculation of biological wastewater treatment facilities as the most urgent problem presently.

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№6|2014

DRINKING WATER SUPPLY

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UDC 543.632.495

Medvedeva T. M., Kolokolova N. N., Skriabin M. E.

Investigating iron bacteria in catalytic biofilm in underground waters at the Velizhany water treatment facilities of Tumen

Summary

Underground water used for drinking water supply of Tumen is characterized by high concentrations of iron and manganese that 1.3–10.59 times exceed the maximum permissible level. Iron and manganese can be efficiently removed from natural water with the help of microbiological oxidation and sorption processes. The studies aimed at analyzing the underground source for the presence of iron bacteria group and determining the rate of catalytical biofilm formation. Water analysis for the presence of iron bacteria was carried out in sand filters of the Velizhany water treatment facilities by microscopic method with the use of iron cytochrome coloring with potassium ferrocyanide on exposed specimen slides. The slides were placed on styrofoam floats installed in the filters of the water treatment facilities. The results of the studies showed that the water from the underground source contained iron bacteria – they were found in catalytic biofilm. It was stated that the rate of biofilm generation with the participation of iron bacteria in sand filters of the Velizhany water treatment facilities at the media level was in average twice as high compared to the level of surface of the water being treated. Mass growth of iron bacteria on sand media proceeded for 8–12 hours; in the water being treated – for 22–24 hours. It might be caused by biological oxidation of iron and manganese at the media level. The studies carried out confirm the possible use of iron bacteria of catalytic biofilm in biological removal of iron and manganese from underground water at the Velizhany water treatment facilities.

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№10|2013

WASTEWATER TREATMENT

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UDC 628.35:661.5

Strelkov A. K., Stepanov S. V., Blinkova L. A., MOROZOVA K. M., Belyakov A. V.

Investigating the processes of single-stage biological treatment
of oil refinery wastewater

Summary

The results of investigating the operation of the Novokuibyshevsk oil refinery waste biological treatment facilities are presented. It was found that denitrification process was not possible in two-stage process of wastewater treatment because of
high concentration of dissolved oxygen in the denitrification tank and low concentration of organics in raw wastewater. Full-scale experiment with single-stage mode of operation of the entire biological treatment facilities was carried out. After the first-stage aeration tanks de-commissioning the total activated sludge amount in the system increased almost 1.5-fold. Sludge concentration in the aeration tanks (of the second stage) increased from 0.5–1 to 2–2.5 mg/l; COD sludge load was reduced from 143 to 77 mg/(g·day). The improved nitrification efficiency and denitrification start were recorded. Kinetic constants were determined for the processes of organics and oil products oxidation, for nitrification and denitrification required for designing wastewater treatment facilities with nitrification-denitrification technology. Inhibition by substrate was found at the concentration of oil products in effluent higher than 4 mg/l. Nitrification inhibition was observed at ammonia nitrogen concentration in effluent higher than 1 mg/l. The full-scale experiment of conversion of the Novokuibyshevsk oil refinery waste biological treatment facilities to one-stage operation provided for testing on commercial scale the advanced nitrification-denitrification technology and recommending this process flow scheme for the introduction at other RF oil refineries.

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№5|2013

WASTEWATER TREATMENT

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UDC 628.35:661.5

Stepanov S. V., SHVETSOV V. N., MOROZOVA K. M., Belyakov A. V., Blinkova L. A.

Investigating nitrification-denitrification technologies of oily wastewater treatment

Summary

The results of investigating biological treatment by nitrification-denitrification technology of oily wastes of the Novokuybyshevsky oil refinery are presented. Possible meeting the advanced requirements to the effluent quality in relation to nitrogen compounds, particularly, by industrial wastewater treatment without blending with municipal wastewater is shown. The kinetic constants of nitrification-denitrification processes and oxidation of oil products required for designing wastewater treatment facilities are determined.

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№11|2011

МГСУ - 90 лет

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UDC 628.35:661.5.63

Gogina Elena

Investigating process flow scheme of wastewater biological treatment for the upgrade of the treatment facilities

Summary

The results of experimental investigations of the process flow scheme of wastewater biological treatment are given. The process of ammonia nitrogen removal from wastewater under low oxygen concentration conditions was studied. Kinetic functions for calculating ammonium nitrogen concentrations in treated water at bioreactor operation were determined. The technology was applied in the construction and upgrade of the treatment facilities in a number of cities and settlements of the Moscow Region.

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№12|2018

WASTEWATER TREATMENT

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UDC 628.315.2

Shuvalov M. V., Tarakanov D. I.

The history of the Samara wastewater treatment facilities project
designed by engineer V. G. Lindlei

Summary

«Drainage of Samara» project was designed by engineer V. G. Lindlei in 1907. Technical and process solutions approved in the project were at that time most advanced. Domestic, industrial wastewater and surface runoff was treated at «designated» facilities that included grit chambers and «moving screens» with a bar spacing of 5 mm. The removal of captured pollutants was completely automated. Extraction of other pollutants was supposed to execute at the «treatment facilities». For this purpose covered horizontal settling tanks with hydraulic sludge removal systems were designed. Biological wastewater treatment was to be carried out in oxidation basins (total surface area about 16 hectare) filled with feed. For wastewater transportation collectors of piriform 1400×1750 mm cross section were planned for construction. According to literary resources at those times wastewater treatment facilities were only in four cities; at that in Odessa, Kiev and Moscow they were represented by sewage fields, and the only treatment facilities with biofilters were built in Tsarskoe Selo.

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