scholarly journals Aeration Tank Microbial Aerosols as a Factor of Water Bodies’ Pollution

Author(s):  

Aeration impact on aerosols discharge from aeration tanks in the process of domestic waste water treatment has been considered. Waste waters and their aerosols microbial pollution has been shown. New regularities of the temperature, time, and wind velocity on moisture discharge and microbial pollution in the form of aerosols from water surface of the biological treatment aerated facilities have been obtained. The equations that enable to calculate moisture emission from water surface in the process of aeration are presented. Water losses in the form of aerosols in the process of aeration depending on the outside air temperature and wind velocity were determined theoretically and experimentally. The microorganisms specific discharge from an aeration tank equal to 2.144 г/(m2∙s) in terms of coliform species was calculated. The microbial pollution maximal concentration values for various meteorological conditions were determined for performance of standard calculations of microbial discharges with aerosols from aeration tanks. The obtained equations can be used in designing of engineering measures aimed at reduction of the discharged aerosols negative microbial impact on water bodies adjacent to the territories of domestic waste waters biological treatment facilities.

Formulation of the problem. When solving hydrological problems associated with the water balance of water bodies and the possibility of economic use of their water resources, an important problem is the accurate determination of evaporation from the water surface, which is the main component of water losses. Review of previous publications and studies.Currently, many indirect and empirical methods for calculating evaporation from the surface of soil, water and vegetation, developed by domestic and foreign scientists: M.I. Budyko, V.S. Mezentsev, A.R. Konstantinov, N.N. Ivanov, Penman-Monteith and others, are used. Most empirical methods do not have universal applicability, since, in most cases, they cannot take into account the features of various underlying surfaces and hydrometeorological conditions that affect evaporation processes. The only acceptable methods for estimating actual or potential evaporation can only be parametric models based on a numerical solution of the surface heat balance equation. One of such models is the atmospheric surface layer model – model SLEB, created at Odessa State Ecological Environmental University. Purpose. The purpose of this study is to obtain quantitative estimates of changes with evaporation of water surfaces with SLEB model and compare them with the measured and model data of analogous methods obtained by other authors (Ivanova, Penman), for example, a freshwater lake Yalpug. Methods. For research, a parametric energy balance model of the atmospheric surface layer SLEB, which is used standard meteorological information, was used. The main advantage of this model is the high accuracy of determining the heat expenditure for evaporation in the calculation of mass-heat transfer between the underlying surface and the atmosphere at the micro- and mesoscales. The SLEB model is applicable for all types of underlying surfaces characteristic of the territory of Ukraine. Results. The value of evaporation from unit area of the water surface of Lake Yalpug calculating by model SLEB was obtained for the first time taking into account the development of wave formation on the surface of the lake, which changes the hydrodynamic properties of the water surface and the aerodynamics of the air flow. Accounting for the effect of wind waves on the vast lake surface allowed us to obtain results almost equal to the measured evaporation from the pool surface. The results showed that the calculated values of evaporation from the water surface by the methods of Penman and Ivanov overestimate the amount of evaporated moisture compared with the values measured and calculated by the SLEB model. Conclusions. Application of the SLEB model allows to increase the quantitative estimation accuracy of the water balance main component – water losses due to evaporation from the water bodies water surface, which, in turn, can increase the water resources management efficiency of natural water bodies for purpose of their rational use for drinking water supply and land irrigation.


2017 ◽  
Author(s):  
Essi Malinen ◽  
Nico Id ◽  
Sanni Valtonen ◽  
Janne Hakala ◽  
Tiina Mononen ◽  
...  

The purpose of this study was to examine how efficient a biological treatment process is in purifying car wash waste waters. Two Finnish automatic car washes having rotating bed biofilm reactors for waste water treatment were included in the study. Both of them are using 87 % of recycled water per car wash and only from 35 to 60 liters of fresh water. Samples were taken from the purified water tank every second week altogether seven times between the beginning of February and the end of May, 2012. The reduction of surfactants was at least 95 % and reduction of chemical oxygen demand (COD) between 87 and 95 % during the sampling period. Outdoor temperature seems not to have any significant effect on purification efficiency. Other water quality parameters such as conductivity, pH, oxygen concentration, total solids, and biological oxygen demand (BOD) were found to be on acceptable level based in comparison to values found in the literature. The high concentration of total nitrogen and total phosphorus in the purified water was caused by nutrients added to the bioreactor for optimal conditions for the microbes. In the studied car washes, the waste water treatment process managed to reduce input load considerably. The main challenges for the quality of purified water seems to be optimal nutrient input as well as on-line monitoring system for water quality.


1978 ◽  
Vol 5 (1) ◽  
pp. 26-31
Author(s):  
Frederick L. Hart

This paper discusses the origin and concepts of kinetic model equations and standard specifications used to size a biological treatment system (size of aeration tank and aeration requirements). They are shown to yield very similar calculations for a domestic type of waste water, but may yield much different values if the waste water behaves differently than domestic waste. The kinetic model approach, therefore, should be considered more flexible and superior in its ability to yield appropriate design values.


Author(s):  

A technique for mining/processing plants waste waters treatment has been presented. The proposed solution is based on separate processing of wastes different by the composition with the use of increased quantities of an alkalizating agent. This technique use will enable to improve the quality of water discharged in water bodies up to MPC and to decrease the waste waters adverse impact upon water bodies.


Author(s):  
T. S. Ponomarenko ◽  
◽  
A. V. Breyeva ◽  

Purpose: analysis of predicted water losses for evaporation from the water surface of the Sokolovskiy reservoir and ponds located on the river Kundryuch’ya, within the boundaries of the investigated site on the territory of the Russian Federation from Rebrikovka to the Sokolovskiy reservoir site and the annual distribution of evaporation depending on the percentage availability. An assessment of the possible impact of quantitative indicators of evaporation on the water supply of the river Kundryuch’ya and Sokolovskiy reservoir was made. Materials and methods: for calculating the amount of precipitation, evaporation and irretrievable losses from the water surface of reservoirs located in the basin of the river Kundryuch’ya upstream the Sokolovskiy reservoir section, the formulas for average long-term conditions, formulas for calculating the volumes of evaporation and nonrecoverable losses at P = 10, 25, 50 and 75 % of supply, as well as a contour map were used. The formulas used and the contour map were taken from the textbook by G. V. Zheleznyakov “Hydrology, Hydrometry and Flow Regulation”. Results: the values of monthly evaporation as a percentage of the annual amount, as well as layers and volumes of evaporation for the Sokolovskiy reservoir are given. It has been determined that the share of nonrecoverable losses from the Sokolovskiy reservoir is 0.87, from the rest of the water bodies is 0.13. The amount of nonrecoverable losses at different levels of availability range from 2.64 million m³ (10 %) to 1.85 million m³ (75 %). Conclusions. The research results served as a basis for making a decision on the liquidation or further operation of the existing water retaining structures. In view of the low values of nonrecoverable losses from water bodies, which have an insignificant effect on the quantitative indicators of runoff, the decision was made in favor of further operation.


1998 ◽  
Vol 38 (8-9) ◽  
pp. 145-153 ◽  
Author(s):  
T. Kamiya ◽  
J. Hirotsuji

A new system combining both biological treatment and intermittent ozonation has been developed to reduce excess sludge production with a small amount of ozone. In this system, activated sludge in the aeration tank was circulated via intermittent ozonation. Experimental results have shown that 50% of the sludge generation was cut down with only 30% of the ozone dose required for continuous ozonation. Furthermore, the process had a remarkable effect on maintaining the sludge settling characteristics. The sludge ozonation was almost of little influence on the effluent quality though the slight degradation of effluent quality was observed in few cases. These facts suggested the effectiveness of the newly proposed system for saving costs and stabilizing treatment performance of biological waste water treatment processes.


2014 ◽  
Vol 60 (3) ◽  
pp. 37-45 ◽  
Author(s):  
Martina Drozdová ◽  
Radim Jablonka ◽  
Radmila Kučerová ◽  
Hana Kašáková

Abstract Nitrogen and phosphorus belong to most important biogenic macro elements and both are required for the growth of microorganisms. Sewage waste waters and industrial waste waters from nitrogen production are important sources of organic and inorganic nitrogen compounds in water. Surface water predominantly contains nitrogen in a form of ammonium cations (NH4 +). This knowledge could be used in waste water treatment. The paper deals with a potential application of ozonation in waste water treatment to treat waste water polluted with excessive amounts of organic compounds, primarily containing nitrogen and its subsequent co-application with advanced oxidation processes (AOPs).


Author(s):  

Regularity of heavy metal ions isolation from waste waters with modified montmorillonit hydrosoles has been studied. The agents’ sorption characteristics have been investigated. The possibility of heavy non-ferrous metal ions isolation up to the current norms of permissible discharge to water bodies has been demonstrated.


Author(s):  
Maria Y. Savostyanova ◽  
◽  
Lidia А. Norina ◽  
Arina V. Nikolaeva ◽  
◽  
...  

Retaining of water resources quality is one of the global ecological problems of the modern time. The most promising direction in solving the problem of water resources protection is the reduction of negative environmental influence of waste water from production facilities by upgrading the existing water treatment technologies. To treat utility water, technical and rain water from site facilities of Transneft system entities, the specialists developed and approved standard technological diagrams, which are used in producing treatment facilities. The standard technological diagrams provide for all necessary stages of waste water treatment ensures the reduction of pollution level to normal values. However, during operation of treatment facilities it was established, that to ensure the required quality of waste water treatment with initially high levels of pollution, the new technological solutions are necessary. The author presents the results of scientific-research work, in the context of which the best affordable technologies were identified in the area of the treatment of waste water with increased content of pollutants and non-uniform ingress pattern. On the basis of the research results the technical solutions were developed for optimization of operation of existing waste water treatment facilities by means of using combined treatment of technical and rain waters and utility waste waters and applying bioreactor with movable bed – biochips. The use of bioreactor with movable bed allows the increase in the area of active surface, which facilitates increase and retention of biomass. Biochips are completely immersed into waste waters, and biofilm is formed on the entire volume of immersion area, facilitating retention of biomass and preventing formation of sediments. Due to mixing the floating device with biofilm constantly moves along the whole area of bioreactor, and, in doing so, speeds up biochemical processes and uniformity of treatment. The advantages of a bioreactor with movable bed – its active sludge durability against increased and changing pollutant concentrations, change of waste water temperature and simplicity of application – ensured the possibility of its use for blending utility waters, technical and rain waters.


2007 ◽  
Vol 2 (1) ◽  
Author(s):  
D.A. Danilovich ◽  
M.N. Kozlov ◽  
V.I. Sklyar ◽  
Yu.A. Nikolaev ◽  
N.M. Shchegolkova ◽  
...  

This work demonstrates a possibility of composting of municipal waste waters sludge (WWS) digested during 5-7 days, of the Kuryanovo waste water treatment plants (the city of Moscow) without the use of traditional organic additives – sawdust, peat, thatch. As a recycling filler (repeatedly used), enhancing the porosity of the composted mixture, ribbed polyethylene spheres (∅=8 cm) and wood chips (having dimension of 5-10 cm) were used. Composting was performed efficiently in both cases, however, the use of wood ships had technological and economical advantages. The process of composting was carried out during 2-4 weeks and was composed of classical phases of active heating (a rate of 0.2-0.3oC/h was obtained), maintaining of maximum temperature during 1-2 days, and cooling down to the ambient temperature. During the course of composting, a product was obtained, having attractive organoleptic properties, suitable for application in municipal laying-out of greenery.


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