Method of combined treatment of air terminal wastewater and liquid wastes from dry closets of aircrafts

Author(s):  
М.Г. Зубов ◽  
Е.В. Вильсон ◽  
Д.И. Обухов

В состав сточных вод аэровокзалов входят хозяйственно-бытовые и производственные стоки от технологического оборудования пищеблока. Технологические схемы очистки сточных вод аэровокзалов не предусматривают прием и очистку жидких отбросов от биотуалетов самолетов, которые являются высококонцентрированными по показателям ХПК, азот аммонийный, фосфор. Кроме того, они содержат высокие концентрации дезинфицирующих средств, действующим веществом которых являются четвертичные аммониевые соли (ЧАС), токсичные для микроорганизмов. В результате поступления жидких отбросов на действующие очистные сооружения аэровокзала качественные показатели биологической очистки сточных вод значительно ухудшились, также изменились свойства биоценоза биопленки. Целью исследований являлось определение способа снижения концентрации ЧАС до значений, при которых прекращается токсичное воздействие на биоценоз биопленки, и определение соответствующей технологической схемы. Представлен анализ литературных данных по воздействию ЧАС на микроорганизмы активного ила, на основании которого выполнены лабораторные исследования и разработан способ подготовки жидких отбросов из биотуалетов самолетов для последующей их совместной очистки с хозяйственно-бытовыми сточными водами аэропорта. В ходе испытаний определена эффективность сорбции предварительно регенерированным избыточным активным илом загрязняющих веществ, в том числе и ЧАС. Определены технологические параметры процессов, разработана и внедрена эффективная, надежная, простая в эксплуатации технологическая схема совместной очистки хозяйственно-бытовых сточных вод аэровокзала и жидких отбросов биотуалетов самолетов. The composition of the wastewater of air terminals includes sewage and industrial wastewater from the technological equipment of the food unit. Process flow schemes for wastewater treatment of air terminals do not provide for the reception and treatment of liquid wastes from water closets of aircrafts, that are highly concentrated in terms of COD, ammonium nitrogen, phosphorus. In addition, they contain high concentrations of disinfectants with quaternary ammonium salts (QAS) as an active ingredient toxic to microorganisms. As a result of liquid waste discharge to the operating treatment facilities of the air terminal, the quality indicators of biological wastewater treatment have significantly deteriorated, and the properties of the biocenosis of the biofilm have also changed. The aim of the research was to determine a method for reducing the concentration of QAS to the level where the toxic effect on the biofilm biocenosis ceased, and to develop an appropriate process flow scheme. An analysis of the literature data on the impact of QAS on activated sludge microorganisms is presented; on this basis laboratory studies were carried out and a method was developed for the pre-treatment of liquid waste from aircraft water closets for the subsequent combined treatment with the air terminal sewage. In the course of the tests, the efficiency of pollution sorption, including QAS, by the preliminary regenerated excess activated sludge was determined. The technological parameters of the processes were determined; an efficient, reliable, easy-to-use process flow scheme for the combined treatment of sewage of the air terminal and liquid waste of water closets of aircrafts was developed and implemented.

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2657
Author(s):  
Elwira Nowobilska-Majewska ◽  
Piotr Bugajski

The aim of this study was to determine the condition of activated sludge in the biologic reactor located in the collective wastewater treatment plant in Nowy Targ (Poland) based on OUR tests in the aspect of the impact of sludge’s concentration in the biologic reactor and dependence of BOD5/TN and BOD5/TP in wastewater flowing into the biologic reactor. The analysis was conducted based on test results from 61 samples of activated sludge taken from the biologic reactor and 61 samples of wastewater flowing into the biologic reactor. The analysis included the concentration of sludge in the biologic reactor. The following indicators were analyzed in wastewater flowing into the reactor: biochemical oxygen demand (BOD5), total nitrogen (TN) and total phosphorus (TP). The statistical analysis concerning the impact of the analyzed factors on oxygen uptake rate (OUR) tests was developed based on the Pearson’s correlation coefficient and partial correlation of many variables. Based on the results of the partial correlation analysis, nomograms were developed to determine the condition of activated sludge microorganisms (OUR) based on the BOD5/TN and BOD5/TP connection and knowledge of the sludge concentration in the bioreactor of the treatment plant. The presented nomograms can be formulated for each bioreactor based on activated sludge technology related the load of organic and biogenic pollutants in the wastewater flowing into the bioreactor and the concentration of the sludge in the bioreactor.


2019 ◽  
Vol 237 ◽  
pp. 305-312 ◽  
Author(s):  
Adam Masłoń ◽  
Janusz A. Tomaszek ◽  
Justyna Zamorska ◽  
Monika Zdeb ◽  
Adam Piech ◽  
...  

Author(s):  
N. Lourenço ◽  
L. M. Nunes

Abstract This study benchmarks vermifiltration (VF) as secondary wastewater treatment in three nature-based decentralized treatment plants using life-cycle assessment. The comparison is justified by the comparatively easier and cheaper operation of VF when compared to more traditional technologies, including small rate infiltration (SRI), constructed wetlands (CW), and activated sludge (AS). Standard life cycle assessment was used and applied to three case studies located in southern Europe. Material intensity during construction was highest for VF, but impacts during operation were lower, compensating those of the other phases. Impacts during the construction phase far outweigh those of operation and dismantling for facilities using constructed wetlands and activated sludge, when the number of served inhabitants is small, and due to lack of economies of scale. VF used as secondary treatment was shown to contribute to reducing the environmental impacts, mainly in constructed wetlands and activated sludge. The replacement of CW by VF seems to bring important environmental benefits in most impact categories, in particular in the construction phase. The replacement by VF in facilities with SRI seems to result in the improvement of some of the impact categories, in particular in the operation phase. As for dismantling, no conclusive results were obtained.


Author(s):  
A. Ivanchenko ◽  
A. Savenkov ◽  
D. Yelatontsev ◽  
Y. Maksymchuk

Among the physicochemical methods of deep extraction of pollutants from wastewater, adsorption is of great interest. Prospects for the use of sorbents from natural raw materials in wastewater treatment technologies based on a critical analysis of the technical literature are shown, the choice of research direction is substantiated. The use of natural adsorbent based on sunflower husk in the technology of wastewater treatment from phosphates and resinous substances at high content to minimize their anthropogenic impact on the environment is scientifically substantiated. The kinetics of adsorption of phosphates and resinous substances has been studied, the optimal parameters of adsorption purification have been established, and adsorption isotherms have been obtained. The theory of monomolecular adsorption (Langmuir and Freundlich equations) was used to characterize the sorbent based on sunflower husk and calculate the adsorption parameters. Experimental data on the degree of extraction of phosphates and resinous substances from wastewater using a natural adsorbent based on sunflower husk were obtained, and its specific surface area (200.06 m2/g) was experimentally determined. It was found that the highest efficiency of phosphate removal at the initial content of 21.25 mg/dm3 to 8.75 mg/dm3 from municipal liquid waste is achieved by adding an adsorbent in the amount of 10 g/dm3. With such technological parameters, the degree of waste treatment reaches 59.3%. At the increased concentration of resinous substances of 775 mg/dm3 at a dose of adsorbent of 1.5 g/dm3 duration of adsorption of 40 minutes their maintenance decreased to an extremely safe indicator (less than 25 mg/dm3). and implement them in urban and industrial treatment plants.


2004 ◽  
Vol 50 (3) ◽  
pp. 111-122 ◽  
Author(s):  
A.H. Slade ◽  
R.J. Ellis ◽  
M. van den Heuvel ◽  
T.R. Stuthridge

This paper reviews nutrient issues within the pulp and paper industry summarising: nitrogen and phosphorus cycles within treatment systems; sources of nutrients within pulping and papermaking processes; minimising nutrient discharge; new approaches to nutrient minimisation; and the impact of nutrients in the environment. Pulp and paper industry wastewaters generally contain insufficient nitrogen and phosphorus to satisfy bacterial growth requirements. Nutrient limitation has been linked to operational problems such as sludge bulking and poor solids separation. Nutrients have been added in conventional wastewater treatment processes to ensure optimum treatment performance. Minimising the discharge of total nitrogen and phosphorus from a nutrient limited wastewater requires both optimised nutrient supplementation and effective removal of suspended solids from the treated wastewater. In an efficiently operated wastewater treatment system, the majority of the discharged nutrients are contained within the biomass. Effective solids separation then becomes the controlling step, and optimisation of secondary clarification is crucial. Conventional practice is being challenged by the regulatory requirement to reduce nitrogen and phosphorus discharge. Two recent developments in pulp and paper wastewater treatment technologies can produce discharges low in nitrogen and phosphorus whilst operating under conventionally nutrient limited conditions: i) the nutrient limited BAS process (Biofilm-Activated Sludge) which combines biofilm and activated sludge technologies under nutrient limited conditions and ii) an activated sludge process based on the use of nitrogen-fixing bacteria. Aerated stabilisation basins often operate without nutrient addition, relying on settled biomass in the benthal zone feeding back soluble nutrients, or the fixation of atmospheric nitrogen. Thus effective nutrient minimisation strategies require a more detailed understanding of nutrient cycling and utilisation. Where it is not possible to meet discharge constraints with biological treatment alone, a tertiary treatment step may be required. In setting nutrient control guidelines, consideration should be given to the nutrient limitations of the receiving environment, including other cumulative nutrient impacts on that environment. Whether an ecosystem is N or P limited should be integrated with wastewater treatment considerations in the further design and development of treatment technology and regulatory guidelines. End-of-pipe legislation alone cannot predict environmental effects related to nutrients and must be supplemented by an effects-based approach.


2021 ◽  
Author(s):  
Pedro Eulogio Cisterna Osorio ◽  
Barbara Faundez-Miño

Fats and oils present in wastewater are usually eliminated by physical and biological processes. In this experience, the fatty wastewaters are treated biologically, and it assesses the impact of the mix in the fats and oils biodegradation and carried out the experiments in a laboratory scale unit. The biodegradation of fats and oils was analysed in two sceneries, with mix previous by mechanical agitation and without mix. Key parameters were monitored, such as the concentration of fats and oils in the influents and effluents, mass loading, and the efficiency of biodegradation. The mass loading range was similar in both sceneries. In the experimental activated sludge plant without mix, the biodegradation of fats and oils reached levels in the range of 28 to 42.5%. For the wastewater treatment plant with a previous mix by mechanical agitation, the levels of biodegradation of fats and oils ranged from 64 to 75%. Therefore, considering the efficiency of the biodegradation of fats and oils in both sceneries, the results indicated that the level mix is a high incidence.


2021 ◽  
Vol 13 (21) ◽  
pp. 12293
Author(s):  
Catarina Silva ◽  
Maria João Rosa

This paper proposes a simple and easy-to-use methodology for forecasting the impact of changes in influent chemical oxygen demand (COD) and in the emission limit values (ELVs) of COD and total nitrogen on average energy requirements for aeration and sludge production by activated sludge wastewater treatment plants (WWTPs). The methodology is based on mass balances of sludge production and oxygen requirements for carbonaceous material biodegradation and/or nitrification, oxygen transfer and aeration equipment efficiency. Using average values of historical data of regular monitoring (water quality and operating conditions) WWTP-specific equations of oxygen requirements, energy consumption and sludge production are derived as a function of influent COD and influent N-total, which may be used to quantify the impact of influent and ELV changes. The methodology was tested in five extended aeration WWTPs for three scenarios established by the utility. The results show that increasing influent COD, from 900 to 1300 mg/L, for example, significantly increases the energy consumption by 49% and sludge production by 53%. For influent 54–68 mg/L N-total, imposing 15 mgN/L ELV results in a 9–26% increase in energy consumption. The COD ELV change studied (season-specific, from 150 mg/L 12 months/year to 125 mg/L 8 months/year to 100 mg/L 4 months/year) increases the energy consumption by 1.8–2.6% and the sludge production by 4.3–5.4%.


2021 ◽  
Author(s):  
Hossam Abdel Rahman

The activated sludge process in Wastewater Treatment Plant (WWTPs) relies on the activities of microbes to reduce the organic and inorganic matter and produce effluent that is safe to discharge into receiving waters. This research examined the effects of non-steroidal antiinflammatory drug (NSAID) ibuprofen and the antibiotic tetracycline on the microbial population in activated sludge from the Humber WWTP. The current investigation was designated to observe the impact of these contaminants, at low (environmentally relative concentrations) as well as extremely high concentrations of tetracycline and ibuprofen. Using 16S and 18S rRNA gene primer sets, and qPCR the abundance of each population was monitored as well as the relative abundance of two populations under the various conditions. It was found that current environmental concentrations of ibuprofen stimulated protozoan growth but higher concentrations reduced their numbers especially in the presence of tetracycline. Finally using DGGE, the identity for some of the more abundant protozoa were identified and it was noted that high ibuprofen and tetracycline concentrations favored the abundance of some genera.


2021 ◽  
Author(s):  
Hari Seshan ◽  
Ezequiel Santillan ◽  
Florentin Constancias ◽  
Uma Shankari Chandra Segaran ◽  
Rohan B. H. Williams ◽  
...  

Biological wastewater treatment systems are often affected by major shifts in influent quality, including the input of various toxic chemicals. Yet the mechanisms underlying adaptation of activated sludge process performance when challenged with a sustained toxin input have not been studied in a controlled and replicated experiment. Three replicate bench-scale bioreactors were subjected to a chemical disturbance in the form of 3-chloroaniline (3-CA) input over 132 days, following an acclimation period of 58 days, while three control reactors received no 3-CA input. The nitrification process was initially affected by 3-CA input; yet all three treatment reactors evolved to biologically degrade 3-CA within three weeks of the experiment, resulting in partial nitrification recovery. 16S rRNA amplicon sequencing revealed that ammonia oxidizers were initially impacted by 3-CA, and a new ammonia oxidizing community emerged with the onset of 3-CA degradation. Combining process and microbial community data from amplicon sequencing with potential functions gleaned from assembled metagenomics and metatranscriptomics data, 3-CA degradation was shown to likely occur via a phenol monooxygenase followed by ortho-cleavage of the aromatic ring. The relative abundance of genera Gemmatimonas, Saprospiraceae OLB8 and Taibaiella correlated significantly with 3-CA degradation. This study demonstrated the impact of a sustained stress on the activated sludge community and wastewater treatment process and its subsequent recovery. Using a combination of techniques in a controlled and replicated experiment, we showed that microbial communities can evolve degradative capacity following a sustained xenobiotic input, specific functions like nitrification can fully or partially recover and targeted culture-independent approaches can be used to elucidate the mechanisms of adaptation.


2005 ◽  
Vol 51 (1) ◽  
pp. 81-88 ◽  
Author(s):  
C. Beck ◽  
G. Prades ◽  
A.-G. Sadowski

The principal objective of our study was to optimise a municipal activated sludge wastewater treatment plant (WWTP) to face high organic flows due to viticulture effluents inputs. Treatment file optimization consisted in testing different treatment lines, changing the number and volume of biological basins and clarifiers, with or without a buffer basin upstream, with a view to achieving a better reduction of COD. The actual WWTP biological stage is composed of two aerated basins whose total volume is 1365 m3. The studied cases are successively, the installation of a single basin of 1365 m3, then of several basins whose total volume remains constant and equal to 1365 m3. Another case was also considered, that of an aerated basin followed by a first clarifier and then, by another aerated basin and a second clarifier. All scenarios presented below were evaluated, for standard dry weather conditions and for high organic load conditions, as encountered during the grape harvest period. The method used was to carry out various simulations, using numerical modelling, and to compare the impact of different process line scenarios and management strategies on the activated sludge WWTP efficiencies.


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