"Вестник МГСУ"

Subject: the results of the analysis of the dynamics of changes in the quality of surface waters in the Lower Volga basin are presented based on the processing of statistical data on the long-term monitoring of their contamination degree. Significant all-season excesses of the maximum permissible values for the concentration of a whole range of background and anthropogenic pollutants in water were recorded. We identified the shortcomings of implementation of the existing methods that allow us to assess the dynamics of the state of the water basin ecosystem and choose the most essential parameters for constructing a mathematical model of selection of the most effective wastewater treatment technology. Research objectives: selection and evaluation of the input parameters of the mathematical model, the implementation of which will ensure the search for the optimal technology and appropriate technical solutions for cleaning surface sewage. Materials and methods: the conducted study is based on a comprehensive assessment of a wide range of hydro-chemical indicators of contamination of discharged wastewater in controlled locations using statistical methods for processing experimental data. Results: we identified the most essential parameters that allow us to form a conceptual model, and we determined the degree of their influence on the selection of the optimal solutions and methods of wastewater treatment. Conclusions: conclusions obtained during the study indicate the need for creation of a mathematical model of assessment of the quality of surface sewage treatment in urbanized areas for improvement of technological parameters of treatment facilities.

In the article the working principles of wastewater biological treatment for food companies is reviewed, including dairies and breweries, the waters of which are highly concentrated with dissolved organic contaminants and suspended solids. An example of successful implementation is anaerobic-aerobic treatment plants. Implementation of these treatment plants can achieve the required wastewater treatment at the lowest operational expenses and low volumes of secondary waste generated. Waste water from the food companies have high concentration of various organic contaminants (fats, proteins, starch, sugar, etc.). For such wastewater, high rates of suspended solids, grease and other contaminants are characteristic. Wastewater food industry requires effective purification flowsheets using biological treatment facilities. At the moment methods for the anaerobic-aerobic purification are applied. One of such methods is the treatment of wastewater at ASB-reactor (methane reactor) and the further tertiary treatment on the OSB-reactor (aeration). Anaerobic process means water treatment processes in anoxic conditions. The anaerobic treatment of organic contamination is based on the process of methane fermentation - the process of converting substances to biogas. The role of biological effluent treatment is discussed with special attention given to combined anaerobic/aerobic treatment. Combining anaerobic pre-treatment with aerobic post-treatment integrates the advantages of both processes, amongst which there are reduced energy consumption (net energy production), reduced biological sludge production and limited space requirements. This combination allows for significant savings for operational costs as compared to complete aerobic treatment without compromising the required discharge standards. Anaerobic treatment is a proven and energy efficient method to treat industrial wastewater effluents. These days, more and more emphasis is laid on low energy use, a small reactor surface area, low chemical usage and reduced sludge handling costs. When stringent discharge limits have to be met, in many cases anaerobic treatment is followed by aerobic post treatment. During aerobic polishing, final traces of organic pollution (COD/BOD) and nutrients such as nitrogen and phosphorous can effectively be removed. Besides the decrease in the biosolids quantity, the quality of the aerobic sludge is often improved. With anaerobic pre-treatment biodegradable carbohydrates are less easily present in the aerobic reactor inlet. As a result, the number of filamentous bacteria causing bulking sludge in activated sludge plants, is significantly reduced. This results in an improved settleability of the aerobic sludge and consequently a more stable and secure operation of the activated sludge plant. Finally, due to the higher mineralization grade dewaterability of aerobic sludge from activated sludge plants after anaerobic pre-treatment it is often better than without anaerobic pre-treatment.

The author presents the results of microbiological studies aimed at investigating the deep removal of phosphates from household wastewater. A method for deep cleaning of waste water using reinforced materials is provided. The living culture study in activated sludge and biofilm in the light microscope showed activating effect of the reinforced loading material on the life of microflora in activated sludge and biofilm. A steel wire in the the feed material has a significant impact on the number and variety of species of protozoa in the activated sludge, and also leads to rapid development of Chlorella sp. The study of the living culture of activated sludge and biofilm in the light microscope showed that the reinforced material activates the vital functions of the activated sludge microflora and biofilms, as well as the diversity of their species composition. The studies have confirmed that chlorella multiplies in an environment rich with iron, absorbs phosphorus from the environment and actively produces oxygen, providing bacterial biomass with it. This fact explains the increase in the removal of organic contaminants, as well as the influence of the reinforced material on the second step of nitrification.

In Russia the standards for wastewater discharge have increased in the nineties of the twentieth century, and the main question was the removal of nutrients. In recent years there have been many studies in order to develop new methods of wastewater treatment, and to adopt Western technologies in Russian treatment plants. But the main problem now is that most of the plants in Russia were built more than thirty years ago. And now they need reconstruction. It requires great financial investments, but the possibilities are limited. Therefore it is necessary to reconstruct with minimal expenses, maximum usage of existing tanks and equipment, and the quality of wastewater treatment satisfying the standards. In Moscow State University of Civil Engineering (MGSU) extensive researches are carried out in the field of biological wastewater treatment, including the removal of nutrients. The results of the researches were used for constructions and reconstructions of treatment plants in Russia.Technological Scheme «Deep biological wastewater treatment system with ammonium-nitrogen removal», which was developed and patented in MGSU, treats wastewater biologically in the aeration tank, which is divided into a sequence of alternating anoxic and aerobic zones. The reconstruction of biological treatment plants under this Scheme is possible at minimal cost, and the quality of treatment satisfies the modern standards.Nowadays, in the Russian Federation there are about sixty two percent of plants with aeration tanks, thirty three percent of biofiltration plants, and five percent of the plants with only mechanical treatment. The main task of the present research was to investigate the possibility of applying single-sludge denitri-nitrification system in the reconstruction of wastewater treatment plants in the Russian Federation. Only plants with aeration tanks were studied, because only they can be reconstructed with the use of the Scheme.The research includes fifty three treatment plants of different Russian cities. According to the questionnaires the data for each treatment plant has been received. The date concerns influents and effluents, the features of a construction and operation of the structures at a station and the data about the cost of aeration in the aeration tanks and so on. The location of the studied treatment plants can be found on the map present in the article.From the initial data the basic parameters of the aeration tanks were calculated, including the amount of air required for denitrification and nitrification. The calculation of the required air amount has been carried out using the method developed in MGSU. This method includes both normative calculations and practical experience of operating procedure of the aeration tanks (working with the single-sludge denitri-nitrification scheme). The results of the calculations were compiled for further analysis.According to the analysis, sixty five percent of the studied wastewater treatment plants may be reconstructed according to the single-sludge denitri-nitrification scheme. It will lead to a serious improvement of wastewater treatment quality.It is important to note, that the calculations were made on the basis of air amount produced by the existing station`s blowers. Therefore reconstructions don`t require replacement of blowers and can be done stage-by-stage.

The findings of the research project that encompasses 137 small municipal wastewater treatment plants (WWTP) are presented in the paper. The source data for the research is the official statistical reporting according to Form № 2-TP (water) submitted in 2010, as well as the information on completed and approved projects that demonstrate admissible discharge standards.
The method of environmental assessment of barrier capabilities of municipal WWTP based on six major indicators (TSS, BOD, N-NH4+, N-NO2-, N-NO3-, P-PO43-) is proposed to ensure compliance with the present-day environmental standards.
The maximal likelihood of incompliance with the pre-set standards is demonstrated by phosphorus phosphate (97 %), ammonium nitrogen (95 %) and nitrite nitrogen (79 %). The substances that demonstrate their maximal excessive content in the wastewater include phosphorus phosphate (its content exceeds the admissible standard 18-fold), ammonium nitrogen (21.7-fold excess) and nitrite nitrogen (7.6-fold excess).This overview indicates a low possibility of compliance of the content of N-NH4+, N-NO2-, and P-PO43- with the environmental standards that extend to biological WWTPs.
The highest relative excess of the admissible content of admixtures is typical for the plants that have a design capacity of 600-800 m3/day and that process 50-200 m3/day. The lowest relative excess of the admissible content of admixtures is typical for the plants that have a design capacity of over 1,000 m3/day and that process over 500 m3/day. The average relative excess of the admissible content of admixtures for all plants equals to 8.4 times.
The ecological assessment of the barrier capabilities of small municipal WWTPs has proven that their compliance with the standards of admissible content of N-NH4+, N-NO2-, and P-PO43- in the wastewater is impossible to attain in practice.

The subject matter of this paper is the operation of Kotlass pulp and paper plant. The amount payable by the plant for the discharge of pollutants into the basin of the Northern Dvina River represents its substantial performance indicator. The pollutant discharge payment is minimal, if the maximal permissible discharge limit is not exceeded. Otherwise, the payment amount goes up. If the concentration of discharged pollutants may cause degradation of the water body, the amount would be by far bigger, given the cost of the water body recovery. If the quality of discharges is higher than the one declared, or if the quality of the discharges is higher than the quality of the water in the recipient water body, the enterprise is exempt from a fraction or the whole of the tax amount due and payable.
The analysis of the wastewater discharged by this enterprise has proven that the major portion of the pollutant discharge payment represents the amount due and payable for excessive discharges that fall beyond the limits. The diagrams that accompany the paper constitute a clear representation of this statement.
Three streams of wastewaters discharged by Kotlass pulp and paper plant are delivered into surface fishery waters. The composition of each wastewater stream and the per-pollutant payment amount is provided in the tabular form. The top five pollutants that account for 97 % of the payment amount have been identified. The major pollutants include methanol (54 % of the discharge payment) and suspended solids (21 % of the discharge payment).
On the basis of the above, the principal environmental protection plan of actions was developed to assure that the maximal permissible discharge limit is not exceeded by Kotlass pulp and paper plant. The proposed plan is designated to resolve specific process-related issues from the viewpoint of economy and environmental protection. Its implementation will reduce discharges of suspended solids by 50 %, whereas the concentration of methanol in the wastewater will also go down.

Introduction. One of the most significant environmental problems facing the Vietnamese city of Hanoi is anthropogenic pollution of surface water, especially in the To Lich river system. Currently, these rivers accept large quantities of wastewater from urban areas and industrial zones, which effluents are not treated prior to discharge into water bodies. The results of the study show that surface water in Hanoi has been contaminated by direct discharge of domestic and industrial wastewater. Considered the To Lich river system, including the To Lich, Lu, Set and Kim Nguu rivers, which receive sewage pollution from urban areas, industrial zones and other sources. Materials and methods. The most common approach to improving the situation is to identify sources of syrface water pollution and assess the quality of To Lich river and its tributaries in order to develop and propose effective and synchronous solurion for the management of water safety and quality in the water bodies of Hanoi city. The water samples were preserved and analysed in the laboratory of Environmental Analysis in accordance with standard Vietnamese methods. For this purpose, analytic apparatus, including Shimadzu AAS 6800 atomic absorption spectrophotometre (Japan), UV-VIS spectrometre, as well as a number of common laboratory instruments and equipment, are used. Results. The results of the study show that surface water in Hanoi has been contaminated by direct discharge of domestic and industrial wastewater. For many years, the rivers have been covered with rubbish, with the water turning black in colour and having an unpleasant smell. The primary cause of the pollution is drainage from many surrounding households discharging waste water directly into the rivers. Conclusions. In order to restore the aqueous ecosystems of Hanoi city, it is necessary to conduct continuous environmental monitoring of changes in the state of water bodies and develop effective and timely solutions for the management of safety and quality of water in the waterways of Hanoi.

Subject: the article focuses on investigation of kinetics of sludge liquor sedimentation and on determination of its characteristics; the relations between parameters of activated sludge such as mixed liquor suspended solids (MLSS), sludge-water phase boundary and sedimentation rate are highlighted. Research objectives: research on kinetics and parameters of activated sludge sedimentation at city wastewater treatment plants (WWTP). Materials and methods: field tests of sedimentation process of real sludge samples from different WWTP in laboratory cylinders are conducted, mathematical and graphical processing of the obtained results is carried out. Results: kinetics of sedimentation of sludge liquor with MLSS equal to 0.6…6.2 mg/l is described, main dependencies between sedimentation characteristics of activated sludge are obtained. The regularities of sedimentation of sludge with small and large MLSS are noted. Conclusions: kinetics of sludge sedimentation for various MLSS is determined, the rate of elimination of “sludge-water” phase boundary is determined.