Flotation technologies for purification of filtration waters of solid waste landfills
V.P. Meshalkin, V.S. Kovalenko, G.A. Shcherbakova, A.V. Kolesnikov
Section: Methodology and research methods. Models and forecasts
Comparison of leachate water treatment methods for solid household waste (MSW) landfills is carried out. The experiments were carried out on model solutions and real filtrate from the MSW landfill of the Moscow region. It has been established that electroflotation treatment is an effective method due to high recovery rates, low energy consumption, as well as the possibility of automation and the absence of secondary water pollution. The effect of surfactants (surface-active substances, SAS), flocculants, Ca, Mg, Ba reagents on electroflotation extraction of UltraPAC coagulant in aqueous solutions of NaCl, Na2SO4 is described. It was found that the addition of an anionic surfactant to the system promotes the
adsorption of the surfactant on its surface, which makes it more hydrophobic, increasing the degree of electroflotation extraction to 95–99% in some cases.
The results of measurements of the particle size, surface charge of the dispersed phase of the UltraPAC co-he results of measurements of the particle size, surface charge of the dispersed phase of the UltraPAC coagulant are presented. It was found that the ζ-potential of Al(OH)2Cl in NaCl solutions in a wide range of pH 5–9 is positive, (+5–+33 mV). In Na2SO4 solutions at pH 7 surface recharge is observed, which is explained by the specific adsorption of SO4 2- anions on the surface of the dispersed phase of Al(OH)2Cl. The particle size varies from 38 μm (pH 5) to 12 μm (pH 9) – in Na2SO4 solutions and from 16 μm (pH 5) to 19 μm (pH 9) – in NaCl solutions. It was found that the addition of Ca2+, Mg2+ reagents to the solution for pH adjustment leads to suppression of the electroflotation process. The introduction of an anionic surfactant stabilizes the electroflotation process and increases the degree of extraction of the coagulant to 75% (MgCl2 – 0.1 g/L) and 99% (CaCl2 – 0.1 g/L).
Studies of the sorption process of extracting Fe3+ and Al3+ ions from aqueous solutions of sodium chloride, nitrate and sulfate salts in a static mode on an industrial powder sorbent of the OU-A brand have been carried out. The influence of Cl-, NO3- and SO42- anions on the value of sorption of metal cations was determined. By the nature of the adsorption isotherms of metal ions, an assumption about the mechanisms of the process was made. The values of the electrokinetic potential of coal particles in salt solutions were obtained, on the basis of which flocculants were selected and their effect on the efficiency of the electroflotation process for extracting spent carbon sorbent was evaluated. It was found that the spent sorbent with Fe3+ ions in an amount of up to 1 g/l, and the sorbent with Al3+ ions – up to 1.6 g/l within 10 minutes can be extracted from solutions of nitrate and sodium chloride salts by adding flocculants of cationic and nonionic types. The experimental studies have shown that the use of a combined method, including sorption treatment with subsequent extraction of the spent sorbent in the process of electroflotation, will not only reduce the duration of wastewater treatment, but also provide a high degree of their purification.
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-160-166
Views: 18
Catalytic oxidative degradation of the azorubine dye in wastewater
T.V. Kon’kova, I.S. Belkina, A.D. Stoyanova, V.A. Kolesnikov
Section: Ecologization of industry
The production of high-quality phosphate fertilizers, in particular calcium acid phosphates, requires the use of ore
rich in phosphates (above 28 wt.% P2O5
) and containing a minimum amount of impurities, including harmful ones.
The absence of such large natural deposits leads to the need to enrich the existing phosphate ore containing an average
amount of phosphates (14–23% P2O5
) and contaminated with various impurities. Enrichment of polymineral phosphate
ores leads to the production of their concentrates and waste (sludge). Sludge is a mixture of clay impurities, iron compounds, phosphate substances contained in the original ore, as well as toxic surfactants used in its flotation enrichment.
This prevents the use of sludge as a secondary source of raw materials in any industry and its return to waste deposits.
The lack of methods for processing sludge leads to their accumulation and environmental pollution: the area of
fertile land is shrinking, pollution of nearby natural water bodies increases. The proposed integrated physicochemical
technology for processing phosphate ore dressing wastes using nitric acid is aimed at improving the environmental
situation in the regions producing phosphate raw materials and obtaining a number of valuable products important for
the national economy: glauconite sand, clay, hydrogen phosphate and calcium nitrate. The yield of sludge processing
products was experimentally established, which amounted to: 68.6% glauconite, 6.91% clay, 12.9% technical calcium
hydrogen phosphate, 18.2% technical calcium nitrate. Processing products – clay and glauconite sand are most widely
used in the construction industry, in particular, in the production of bricks and concrete. Glauconite sand and clay are used in the production of sorbents, paints and primers. Hydrophosphate and calcium nitrate are used in agriculture as
phosphorus and nitrogen fertilizers, respectively.
Keywords: phosphatic ore, slimes, the nitric-acid method of processing of a waste, glauconitic sand, clay, hydrophosphate of lime, nitrocalcite
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-154-159
Views: 11
Methodology for determining regional thresholds for the calculation of standards for the permissible discharge of liquid industrial waste into surface waters
Section: Methodology and research methods. Models and forecasts
Water quality standards are a key tool for regulating anthropogenic pressure on water bodies. A scientificallybased approach to the development of regional water quality standards is the use of modern mathematical methods for
the analysis of experimental data and information technologies. We have developed a methodology for determining
regional threshold standards for permissible discharge of liquid industrial waste for selected types of surface waters.
The presented methodology uses a symbiosis of cluster analysis and expert evaluation methods, which allows to increase
the validity of the results obtained. The typification of surface waters was carried out for water bodies of the territory
of the Republic of Tatarstan on the basis of long-term systematic observations. Clustering was carried out according
to the sets of all determined hydrochemical indicators using Kohonen neural self-organizing networks implemented
in the author’s neural network filtering model. Experts in the relevant subject area acted as experts to assess the
homogeneity of data groups in each of the selected clusters. Each heterogeneous group established by experts was
divided into clusters using the Kohonen neural network until the required uniformity was achieved. Based on expert
analysis, hydrochemical indicators, which had a uniform variability of values and did not allow water typing, were
excluded from further evaluation. According to the values of other hydrochemical indicators, six types of waters are
distinguished. Threshold values of hydrochemical indicators for clusters corresponding to the upper threshold of the
variational series of values are determined. The obtained regional threshold concentrations for each type of water are
proposed to be used to calculate the standards of permissible discharges during the disposal of liquid waste into water
use facilities located in the Volga-Kama basin.
Keywords: liquid production waste, discharge, water bodies, neural network technologies, regional threshold concentrations, standards permissible discharges
Section: Monitoring of natural and anthropogenically disturbed areas
Studies have been carried out to assess the degree of soil pollution in Armenia with heavy metals (HM) near existing
(Kajaran Copper-Molybdenum Plant and Hrazdan Cement Plant) and currently not operating (Alaverdi Mining and Metallurgical Plant and Vanadzor Chemical Plant) industrial enterprises. The selection of soil samples was carried out from
the plots at a distance of 0.5, 1.5, 2.5, 5, 10, 15 and 25 km from the source of pollution. Analysis of the results of chemical
analysis of soils showed that at a distance of up to 5 km from technogenic sources, soils are heavily contaminated with
compounds of copper, zinc and lead. As the distance from the pollution source increases to 25 km, a significant decrease
in the concentrations of all HMs occurs, and the comparative series is represented by the following sequence: Zn > Cu
> Pb > Co > Mo. At a distance of 25 km, a significant decrease in anthropogenic load on the soil is noted. The greatest
50 times decrease in the total HM content was found for soils near the Alaverdi Mining and Metallurgical Combine,
and the smallest in the case of the Hrazdan Cement Plant. For the rest of the considered enterprises, the decrease in the
value of the coefficient of total pollution was 25 times on the average. The information obtained can be used to take into
account the migration and storage capacity of HMs in the soil when organizing environmental measures, depending on
the remoteness of the main source of pollution.
Keywords: soil, heavy metals, anthropogenic pollution, remoteness from the source of pollution, the total coefficient of soil pollution
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-090-097
Views: 13
Active carbons as an important factor in the sustainable development of the economy and the quality of life of the population
V.M. Mukhin, N.V. Korolev
Section: Social ecology
The article indicates the severity of the environmental threats and pollution of the biosphere. The main route of
protection of the biosphere with the use of active carbons (AU) is justified. A modern definition of activated carbon is
given as a material with a developed porous structure, having high absorption characteristics for impurities found in
the media to be cleaned (air, gases, water and other liquids). A new approach to the evaluation of the adsorption properties of AU, justified by Academician M.M. Dubinin through the adsorption activity per unit volume of AU (mg/cm3
),
is proposed. The possibility of effective use of activated carbon in environmental technologies for the protection of the
atmosphere, hydrosphere, lithosphere and man himself as the main object of the biosphere is shown. Special emphasis
is placed on the coverage of the most important areas of application of AU that ensure the environmental safety of the
Russian Federation, namely, detoxification of soils from pesticide residues, purification of drinking water and wastewater, treatment of waste gases from incinerators. It is shown that the introduction of AU in doses of 100–200 kg/ha into
herbicide-contaminated soil allows not only to increase crop yields by 20–80%, but also to obtain environmentally friendly crop products. It is proved that active carbons of the DAS brand based on anthracite with a high volume microporosity
(0.17 cm3
/cm3
) significantly increase the efficiency of drinking water and wastewater treatment. Thus, the sorption
capacity of DAS for phenol, as the most common pollutant of natural and waste water, is 2.5–3.5 times higher than that
of the industrial sorbent KAD-I based on coal semi-coke. A number of problems of protection of the atmosphere with
the use of AU are highlighted. The important role in the use of AU for detoxification of the human body is emphasized.
New promising technologies of AU production are described. The need for AU for the Russian Federation in the amount
of at least 70,000 tons/year is justified, which allows for the sustainable development of the economy and improving the
quality of life of the population.
Keywords: environmental pollution, active carbons, sorbent, biosphere protection technologies, lithosphere, soil detoxification, hydrosphere, water treatment, atmosphere, incineration plants
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-210-217
Views: 5
Bioindication of oil-contaminated soils using invertebrates
E.N. Melekhina, A.A. Taskaeva
Section: Population ecology
The article discusses the possibility of using springtails (Collembola) as an indicator group of soil invertebrates in
the case of oil pollution, as well as the rate of their recovery in soils reclaimed by different methods. Eight experimental
sites were examined with the use of various biological preparations, agrochemical soil treatment and the background
community in the Usinsk region of the Komi Republic. A decrease in the diversity and abundance of springtails, a depletion of the spectrum of their life forms, and a restructuring of the dominance structure on the experimental sites 12 years
after reclamation are shown. The euedaphic and hemiedaphic species were found to be sensitive to oil pollution. Species
characteristic of the initial stages of restoration of soil communities after oil pollution (Ceratophysella succinea, Proisotoma minima, Desoria hiemalis), as well as a species that may be sensitive to oil pollution (Protaphorura jacutica), have
been identified. Analysis of the diversity of springtails can serve as an alternative to ecotoxicological tests in assessing
the effectiveness of reclamation methods and the rate of restoration of disturbed soils.
Keywords: springtails, pollution of terrestrial ecosystems, bioremediation, European part of Russia
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-181-186
Views: 11
Microbiological monitoring of technogenically polluted reservoirs of the Absheron industrial region
А.S. Gasimova, N.M. Ismailov, А.G. Talibly
Section: Monitoring of natural and anthropogenically disturbed areas
The presence of water bodies of anthropogenic origin on the territory of the Absheron industrial region is one of
the acute problems. Many lakes have become receivers of wastewater and polluted water, they have a negative impact on
adjacent environments – soil cover, groundwater and the atmosphere of the entire Absheron Peninsula, including the
capital of the country, Baku, with its three million population. The object of research in 2016–2017 was the largest and
most polluted lakes of the Absheron Peninsula – Boyuk-Shor (the surface of this reservoir is 1300 hectares) and Zykh
(20 hectares). The research is devoted to the study of the structure of the microbiocenosis of reservoirs contaminated with
oil and oil products, biogenicity and their self-cleaning ability. In the self-purification of these reservoirs, oil-oxidizing
microorganisms play an important role, the abundance of which in the water of reservoirs ranges from 103 to 105
cells/dm3
.
The most active decomposition of organic substances in water occurs in the summer and autumn. This is favored, first,
by the temperature factor. The difference in the degree of biogenicity in different zones of water bodies is associated with
high levels of hydrocarbon pollutants, namely: in the areas of pollutant intake, self-cleaning ability does not compensate
for the rate of their destruction.
Keywords: Absheron Peninsula, water bodies, pollution, self-purification, microorganisms, microbiocenosis structure
Article published in number 4 for 2021 DOI: 10.25750/1995-4301-2021-4-083-089
Views: 5
Scientific and methodological aspects of the organization of environmental monitoring of near-aerodrome territories
Section: Methodology and research methods. Models and forecasts
A new approach to environmental monitoring of depositing media of near-aerodrome territories is proposed, aimed at increasing its accuracy and information content while reducing the cost. For this purpose, on the basis of correlation analysis of the results of eleven-year monitoring of the adjacent territory to the airfield of state aviation, the choice of analyte-marker of soil pollution by major pollutants is justified; developed a predictive model of soil pollution specific pollutant (aviation fuel) as a result of his kapleobrazovanie and scattering when the aircraft engines in afterburner at takeoff-landing; the developed method piezosensors rapid determination of analyte-marker in the field; the necessity of accurate calculation of the total score and presented to the ranking scale of total pollution of soils paartronic territories the main pollutants to describe the environmental situation. The proposed scheme of geoecological monitoring includes: prediction of soil pollution with an analyte-marker (kerosene) at different distances from the runway; construction of pixel maps of soil pollution with an analyte-marker based on the results of measurements in the field using a mobile and economical piezosensor measuring device; allocation of related areas with high content of analyte-marker on pixel maps; sampling of soils in the selected associated areas and determination of the content of priority pollutants (kerosene, formaldehyde, nitrates, heavy metals) by standard laboratory methods; calculation of the specified total indicator of soil pollution and construction of analog maps with subsequent decision-making on the rehabilitation of environmentally unfavorable areas. The proposed scheme of geoecological monitoring was tested in the adjacent territories to the airfields «Baltimore» and «Engels-2».
Keywords: environmental monitoring, soil pollution, kerosene, formaldehyde, heavy metals, nitrates, state aviation airfield
A technology of pre-design comparative assessment of hazardous industrial facilities alternative location options is
described in this paper. The technology was designed by the St. Petersburg ecologic and design company Eco-ExpressService LLC. Options’ comparison is carried out in two stages using a score/ranking multi-criteria assessment: at first,
the determination and comparison of environmental safety criteria, and then – a summary assessment of all set of criteria.
4 competitive methods are used for consolidation of obtained results into general comparative scoring. These methods
differ in specification degree of the criteria indicator significance and interrelation of different types of object. Stages
of technology application are illustrated with concrete examples. The pre-design comparative assessment technology
was tested for alternative options of the Russian section of the Nord Stream 2 offshore gas pipeline and the Complex for
processing ethane-containing gas on the territory of the Kingisepp municipal district of the Leningrad region. Main positive effects and advantages of its use are determined by the increase of construction environmental safety and essential
economy of the federal, regional and local budgets and investors by eliminating unfavourable object location options at
early stages of development.
Keywords: environmental safety, production facility, technology of assessment, criteria, anthropogenic impact