scholarly journals Development and optimization of remedial measures to control filamentous bacteria in a full-scale biological nutrient removal plant

2014 ◽  
Author(s):  
◽  
Nashia Deepnarain
Keyword(s):  
Negative Impact ◽  
Filamentous Growth ◽  
Full Scale ◽  
Biological Nutrient Removal ◽  
Ozone Treatment ◽  
Remedial Measures ◽  
Filamentous Bacteria ◽  
Operational Parameters ◽  
Filamentous Bulking ◽  
The Individual

Wastewater treatment plants (WWTPs) frequently experience bulking and foaming episodes, which present operational challenges by affecting sludge settling due to the excessive proliferation of filamentous bacteria. Various control strategies have been implemented over the years to minimize filamentous growth, however, filamentous bulking still remains an unresolved problem in many WWTPs worldwide. The current study focused on developing and optimizing remedial measures viz., specific and non-specific methods to reduce problematic filamentous bacteria in a full-scale WWTP. Specific methods demonstrated the influence of plant operational parameters viz. chemical oxygen demand, influent N-NH4+, food to microorganism ratio, dissolved oxygen, temperature and pH on the abundance of filamentous bacteria. A cumulative logit model was used to determine the significant relationships between the individual filamentous bacteria at present and the prevailing plant operational parameters. Using the above statistical approach, significant observations and predictions were made with respect to the individual filamentous growth under certain operational parameters. With further validation, this model could be successfully applied to other full-scale WWTPs identifying specific parameters that could contribute to filamentous bulking, thus providing a useful guide for regulating specific filamentous growth. Non-specific control methods such as chlorine, ultraviolet irradiation and ozone treatment were investigated on filamentous bacteria using a live/dead staining technique. To achieve at least 50% reduction of filamentous bacteria, a chlorine dose of 10 mg Cl2/L was required, all filaments were killed at a dose of 22 mg Cl2/L. In addition, an effective UV and ozone dose of 4418.91 μw seconds/cm2 and ±20 mg O3/L respectively, was required to kill 50% of the filamentous bacterial population. Among the three non-specific methods, ozone treatment seemed to be an effective method in controlling the filamentous population with a low negative impact to the surrounding environment. This study serves as a useful guide on the problems and control of filamentous bulking in activated sludge plants.

A logistic model for the remediation of filamentous bulking in a biological nutrient removal wastewater treatment plant

2015 ◽  
Vol 72 (3) ◽  
pp. 391-405 ◽  
Author(s):  
Nashia Deepnarain ◽  
Sheena Kumari ◽  
Jordache Ramjith ◽  
Feroz Mahomed Swalaha ◽  
Valter Tandoi ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Wastewater Treatment Plant ◽  
In Situ Hybridisation ◽  
Treatment Plant ◽  
Full Scale ◽  
Biological Nutrient Removal ◽  
Filamentous Bacteria ◽  
Operational Parameters ◽  
Filamentous Bulking

Biological nutrient removal (BNR) systems across the globe frequently experience bulking and foaming episodes, which present operational challenges such as poor sludge settling due to excessive filamentous bacteria. A full-scale BNR plant treating primarily domestic wastewater was monitored over a period of 1 year to investigate filamentous bacterial growth response under various plant operating parameters. Identification of filamentous bacteria by conventional microscopy and fluorescent in situ hybridisation indicated the dominance of Eikelboom Type021N, Thiothrix spp., Eikelboom Type 1851 and Eikelboom Type 0092. A cumulative logit model (CLM) was applied to elucidate significant relationships between the filamentous bacteria and plant operational parameters. The model could predict the potential abundance of dominant filamentous bacteria in relation to wastewater treatment plant operational parameters. Data obtained from the model corroborated with previous findings on the dominance of most filaments identified, except for Type 0092, which exhibited some unique traits. With further validation, the model could be successfully applied for identifying specific parameters which could contribute towards filamentous bulking, thus, providing a useful tool for regulating specific filamentous growth in full-scale wastewater treatment plants.

Extracellular polymers in partly ozonated return activated sludge: impact on flocculation and dewaterability

2006 ◽  
Vol 54 (9) ◽  
pp. 155-164 ◽  
Author(s):  
M.A. Dytczak ◽  
K. Londry ◽  
H. Siegrist ◽  
J.A. Oleszkiewicz
Keyword(s):  
Activated Sludge ◽  
Negative Impact ◽  
Kinetic Studies ◽  
Volume Index ◽  
Biological Nutrient Removal ◽  
Ozone Treatment ◽  
Batch Reactors ◽  
Strictly Aerobic ◽  
Capillary Suction ◽  
Term Operation

The purpose of this study was to evaluate the influence of partial ozonation of return activated sludge on settling properties and dewaterability of sludge. Sequencing batch reactors with two sets of aerobic and alternating anoxic/aerobic conditions were used. In each set, one reactor served as a control and the other was subject to the ozone treatment (doses in the range of 0.016–0.080 mg O3/mg TSS of initial excess sludge). The level of total suspended solids (TSS) in each reactor was controlled at 1,800 mg/l. To evaluate settleability and dewaterability, settling kinetic studies, sludge volume index (SVI) and capillary suction time test (CST) were used. For extraction and quantifying sludge biopolymers, thermal-ethanolic extraction was employed. The ratio of bound-to-total extracellular polymer substances (EPS) was higher for the strictly aerobic reactor than for the alternating anoxic/aerobic one, indicating the stronger structure of the aerobic flocs. After ozone treatment, the fraction of bound EPS was released and solubilized, increasing soluble EPS. Increased apparent food-to-microorganism (F/M) ratio favoured production of EPS in ozonated reactors, enhancing flocculation, which had potential to improve settling. Dewaterability, measured by CST test, was better in alternating anoxic/aerobic reactors than in aerobic ones, indicating that incorporation of an anoxic zone for biological nutrient removal leads to improvement in sludge dewatering. The negative impact of ozonation on dewaterability was minimal in terms of the long-term operation.

Control of Microthrix parvicella and sludge bulking by ozone in a full-scale WWTP

2015 ◽  
Vol 73 (4) ◽  
pp. 866-872 ◽  
Author(s):  
Lotta Levén ◽  
Erik Wijnbladh ◽  
Malin Tuvesson ◽  
Caroline Kragelund ◽  
Sara Hallin
Keyword(s):  
Negative Impact ◽  
Microscopic Analysis ◽  
Full Scale ◽  
Ozone Treatment ◽  
Control Line ◽  
Foam Formation ◽  
Process Data ◽  
Sludge Bulking ◽  
N Removal ◽  
Microthrix Parvicella

Bulking and rising sludge are common problems in wastewater treatment plants (WWTPs) and are primarily caused by increased growth of filamentous bacteria such as Microthrix parvicella. It has a negative impact on sludge settling properties in activated sludge (AS) process, in addition to being responsible for foam formation. Different methods can be used to control sludge bulking. The aim of this study was to evaluate the dosage of on-site generated ozone in the recycled AS flow in a full-scale WWTP having problems caused by M. parvicella. The evaluation of the experiment was assessed by process data, microscopic analysis and microbial screening on the experimental and control line before, during and after the period of ozone dosage. The ozone treatment resulted in decreased abundance of M. parvicella and improved the settling properties, without impairing the overall process performance. Both chemical oxygen demand (COD)- and N-removal were unaffected and the dominant populations involved in nitrification, as analysed by fluorescent in situ hybridization, remained during the experimental period. When the ozone treatment was terminated, the problems with sludge bulking reappeared, indicating the importance of continuous evaluation of the process.

УКРАЇНОЗНАВЧИЙ ОСВІТНІЙ ЧИННИК В УМОВАХ СУЧАСНОЇ УКРАЇНСЬКОЇ МАСОВОЇ КУЛЬТУРИ

2019 ◽  
pp. 22-29
Author(s):  
Н. В. Фрадкіна
Keyword(s):  
Mass Culture ◽  
Personal Development ◽  
Negative Impact ◽  
Educational Process ◽  
Point Of View ◽  
Character Trait ◽  
Main Task ◽  
Leading Role ◽  
The Individual

The purpose and tasks of the work are to analyze the contemporary Ukrainian mass culture in terms of its value and humanistic components, as well as the importance of cultural studies and Ukrainian studies in educational disciplines for the formation of a holistic worldview of modern youth.Analysis of research and publications. Scientists repeatedly turned to the problems of the role of spirituality in the formation of society and its culture. This problem is highlighted in the publications by O. Losev, V. Lytvyn, D. Likhachev, S. Avierintsev, M. Zakovych, I. Stepanenko and E. Kostyshyn.Experts see the main negative impact of mass culture on the quality approach, which determines mass culture through the market, because mass culture, from our point of view, is everything that is sold and used in mass demand.One of the most interesting studies on this issue was the work by the representatives of Frankfurt School M. Horkheimer and T. Adorno «Dialectics of Enlightenment» (1947), devoted to a detailed analysis of mass culture. Propaganda at all socio-cultural levels in the form is similar in both totalitarian and democratic countries. It is connected, according to the authors, with the direction of European enlightenment. The tendency to unify people is a manifestation of the influence of mass culture, from cinema to pop. Mass culture is a phenomenon whose existence is associated with commerce (accumulation in any form – this is the main feature of education), in general, the fact that it exists in this form is related to the direction of the history of civilization.Modern mass culture, with its externally attractive and easily assimilated ideas and symbols, appealing to the trends of modern fashion, becomes a standard of prestigious consumption, does not require intense reflection, allows you to relax, distract, not teach, but entertains, preaches hedonism as the main spiritual value. And as a consequence, there are socio-cultural risks: an active rejection of other people, which leads to the formation of indifference; cruelty as a character trait; increase of violent and mercenary crime; increase in the number of alcohol and drug addicts; anti-patriotism; indifference to the values of the family and as a result of social orphanhood and prostitution.Conclusions, perspectives of research. Thus, we can conclude that modern Ukrainian education is predominantly formed by the values of mass culture. Namely, according to the «Dialectic» by Horkheimer and Adorno, «semi-enlightenment becomes an objective spirit» of our modern society.It is concluded that only high-quality education can create the opposite of the onset of mass culture and the destruction of spirituality in our society. It is proved that only by realizing the importance of cultivating disciplines in the educational process and the spiritual upbringing of the nation, through educational reforms, humanitarian knowledge will gradually return to student audiences.Formation of youth occurs under the influence of social environment, culture, education and self-education. The optimal combination of these factors determines both the process of socialization itself and how successful it will be. In this context, one can see the leading role of education and upbringing. It turns out that the main task of modern education is to spread its influence on the development of spiritual culture of the individual, which eventually becomes a solid foundation for the formation of the individual. Such a subject requires both philosophical and humanitarian approaches in further integrated interdisciplinary research, since the availability of such research will provide the theoretical foundation for truly modern educational and personal development.

MEDIA SOCIALIZATION OF PERSONALITY IN THE CONTEXT OF INMUTATION IN THE MASS MEDIA

2021 ◽  
pp. 104-109
Author(s):  
Chernysh O.O.
Keyword(s):  
Mass Media ◽  
Negative Impact ◽  
Effective Interaction ◽  
Individual Characteristics ◽  
Media Culture ◽  
Active Growth ◽  
Media Space ◽  
The Media ◽  
The Individual

The urgency of the researched problem is connected with the growing role of mass media in modern conditions leads to change of values and transformation of identity of the person. The active growth of the role of the media, their influence on the formation and development of personality leads to the concept of “media socialization” and immutation in the media. The aim of the study is to outline the possibilities of the process of media socialization in the context of immutation in the media. The methods of our research are: analysis of pedagogical, psychological, literature, synthesis, comparison, generalization. The article analyzes the views of domestic and foreign scientists on the problem of immutation in the media and the transformation of the information space. In the context of the mass nature of the immutation of society, the concept of “media socialization” becomes relevant, which is the basis for reducing the negative impact of the media on the individual.The author identifies the lack of a thorough study of the concept of “media socialization” in modern scientific thought. Thus, media socialization is associated with the transformation of traditional means of socialization, and is to assimilate and reproduce the social experience of mankind with the help of new media.The article analyzes the essence of the concepts “media space”, “mass media” and “immutation”. The influence of mass media on the formation and development of the modern personality is described in detail.The study concluded that it is necessary to form a media culture of the individual, to establish safe and effective interaction of young people with the modern media system, the formation of media awareness, media literacy and media competence in accordance with age and individual characteristics for successful media socialization. The role of state bodies in solving the problem of media socialization of the individual was also determined. It is determined that the process of formation of media culture in youth should take place at the level of traditional institutions of socialization of the individual.The author sees the prospect of further research in a detailed analysis and study of the potential of educational institutions as an institution and a means of counteracting the mass nature of the immutation of society.Key words: immutation, media socialization, mass media, media space, information.

Boundaries of Restricting the Rights of Human and Citizen

2020 ◽  
Vol 26 (2) ◽  
pp. 232-236
Author(s):  
Manol Stanin
Keyword(s):  
Negative Impact ◽  
The Individual ◽  
The Right ◽  
Positive Results

AbstractLimitation of rights is a measure proved its effectiveness with positive results for the community in war, military or another emergency.Attitude to rightsmust be human with a view to the right-to-human relationshipbecause the crossing of a certain boundary leads to a disintegration of rights and a negative impact on the personality.This implies necessity from legal institutionalization of clear criteria to refine the limitation of rights, both for the purpose of their protection and for the purpose of protecting the individual.

scholarly journals Microbiome of Seven Full-Scale Anaerobic Digestion Plants in South Korea: Effect of Feedstock and Operational Parameters

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 665
Author(s):  
Michal Sposob ◽  
Hee-Sung Moon ◽  
Dongjin Lee ◽  
Yeo-Myeong Yun
Keyword(s):  
Microbial Population ◽  
Ammonium Nitrogen ◽  
H2 Production ◽  
Full Scale ◽  
Organic Loading Rate ◽  
Operational Parameters ◽  
Sludge Digestion ◽  
Secondary Sludge ◽  
Potential Activity ◽  
Total Ammonium

In this study, the microbiomes linked with the operational parameters in seven mesophilic full-scale AD plants mainly treating food waste (four plants) and sewage sludge (three plants) were analyzed. The results obtained indicated lower diversity and evenness of the microbial population in sludge digestion (SD) plants compared to food digestion (FD) plants. Candidatus Accumulibacter dominated (up to 42.1%) in SD plants due to microbial immigration from fed secondary sludge (up to 89%). Its potential activity in SD plants was correlated to H2 production, which was related to the dominance of hydrogenotrophic methanogens (Methanococcus). In FD plants, a balance between the hydrogenotrophic and methylotrophic pathways was found, while Flavobacterium and Levilinea played an important role during acidogenesis. Levilinea also expressed sensitivity to ammonia in FD plants. The substantial differences in hydraulic retention time (HRT), organic loading rate (OLR), and total ammonium nitrogen (TAN) among the studied FD plants did not influence the archaeal methane production pathway. In addition, the bacterial genera responsible for acetate production through syntrophy and homoacetogenesis (Smithella, Treponema) were present in all the plants studied.

Entrepreneurship in regions: differentiated impacts of the socio cultural and gender types

2015 ◽  
Vol 28 (1) ◽  
pp. 45-76 ◽  
Author(s):  
Claudio Mancilla ◽  
José Ernesto Amorós
Keyword(s):  
Negative Impact ◽  
Positive Impact ◽  
Fear Of Failure ◽  
Content Type ◽  
Reference Models ◽  
Cultural Aspects ◽  
And Gender ◽  
The Individual ◽  
Practical Implications ◽  
Secondary City

Purpose The purpose of this paper is to study the differentiated impact of factors that influence the propensity to entrepreneur in a sample of people in Chile. A distinction is made between individuals that live in primary cities and secondary cities. The differentiating factors are socio‐cultural aspects (reference models – positive examples of entrepreneurs – and perception of social fear of failure) and the gender of the individual. Design/methodology/approach For the research data from the survey used in Chile by the Global Entrepreneurship Monitor for the years 2010 and 2011 were used. A logit model was used to determine the differentiated impact of the analysed factors and interactions were done using the method proposed by Corneliâen and Sonderhof (2009). Findings These showed that the fact that an individual lives in a secondary city decreases his entrepreneurship probability. The positive impact that the reference models have is weaker in women. Contrary to what was expected, the negative impact of the fear of failure perception is weaker in women. Practical implications These results have the implications to suggest focused public policies and differentiations that consider the socio‐cultural, territorial (focused in cities) and gender aspects. Originality/value The research contributes by giving empirical evidence of the existence of the negative impact of living in a secondary city and of differentiated effects of socio‐cultural factors from the gender perspective.

scholarly journals Modeling of Tractor Fuel Consumption

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2300
Author(s):  
Bronisław Andrzej Kolator
Keyword(s):  
Fuel Consumption ◽  
Soil Conditions ◽  
Simulation Studies ◽  
Working Capacity ◽  
Operational Parameters ◽  
System A ◽  
The Individual ◽  
Adjustment System ◽  
Unit Performance ◽  
Efficiency Indicators

In this paper, the energy diagnostic of tractor performance consists in evaluating the energy (fuel consumption per hectare—dm3 ha−1) for a given agricultural operation and in combining it with working capacity, also called productivity (area productivity—ha h−1). One of the methods of solving this problem is the identification of the functioning process of the machine unit. A model of the process of the machine unit performance was developed, considering the operation of the rear linkage system of the implement with the force control adjustment system. In order to analyze the system, a mathematical model of the system function was built: tractor-implement-soil, defining the physical connections and interdependencies between the individual subsystems of the system. Based on this model, a simulation model was developed and implemented in the Matlab/Simulink environment. The Simulink package was used to test the performance of the machine set. The efficiency indicators according to the adopted criteria were calculated in the evaluation block. To evaluate the process, the technical and operational parameters of the tractor, the type and parameters of the tool, and soil properties were taken into account. The results of simulation studies obtained on a validated model are consistent with experimental data from appropriate soil conditions.

ASSESSMENT OF WOODEN BUILDINGS IN TERMS OF CONSTRUCTION WASTE GENERATION

2020 ◽  
Author(s):  
Marcela Spišáková ◽  
Mária Kozlovská ◽  
Jozef Švajlenka
Keyword(s):  
Negative Impact ◽  
Raw Materials ◽  
Environmental Parameters ◽  
Constructional Material ◽  
Waste Generation ◽  
Construction Waste ◽  
Construction Market ◽  
Negative Impacts ◽  
The Individual ◽  
Wooden Structures

Construction industry creates an environment for people's lives. On the other hand, construction activities have a negative impact on various aspects of the environment. It consumes natural raw materials, significantly contributes to carbon footprint, waste, etc. Appropriate choice of constructional, material, technical, technological and environmental parameters of buildings can partially reduce this negative impacts. By designing, implementing and using wood-based constructions it is possible to reduce the negative impact in the area of construction waste generation. Currently, the construction market offers a large number of construction systems of wooden buildings, which have both strengths and weaknesses. In this paper are identified construction systems of wooden buildings offered on the Slovak construction market. The aim of the paper is a detailed identification of construction waste generation during the realization of particular wooden structures and monitoring of waste generation in production factory (off site) and on construction site (on site) during the construction of wooden buildings. Based on the obtained information, the individual construction systems of wood-based constructions are compared in terms of construction waste generation

Sign in / Sign up

Export Citation Format

Share Document