scholarly journals Application of Anammox-Based Processes in Urban WWTPs: Are We on the Right Track?

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1334
Author(s):  
Alba Pedrouso ◽  
José Ramón Vázquez-Padín ◽  
Dafne Crutchik ◽  
José Luis Campos

The application of partial nitritation and anammox processes (PN/A) to remove nitrogen can improve the energy efficiency of wastewater treatment plants (WWTPs) as well as diminish their operational costs. However, there are still several limitations that are preventing the widespread application of PN/A processes in urban WWTPs such as: (a) the loss of performance stability of the PN/A units operated at the sludge line, when the sludge is thermally pretreated to increase biogas production; (b) the proliferation of nitrite-oxidizing bacteria (NOB) in the mainstream; and (c) the maintenance of a suitable effluent quality in the mainstream. In this work, different operational strategies to overcome these limitations were modelled and analyzed. In WWTPs whose sludge is thermically hydrolyzed, the implementation of an anerobic treatment before the PN/A unit is the best alternative, from an economic point of view, to maintain the stable performance of this unit. In order to apply the PN/A process in the mainstream, the growth of ammonia-oxidizing bacteria (AOB) should be promoted in the sludge line by supplying extra sludge to the anaerobic digesters. The AOB generated would be applied to the water line to partially oxidize ammonia, and the anammox process would then be carried out. Excess nitrate generated by anammox bacteria and/or NOB can be removed by recycling a fraction of the WWTP effluent to the biological reactor to promote its denitrification.

2013 ◽  
Vol 69 (3) ◽  
pp. 525-531 ◽  
Author(s):  
C. Cavinato ◽  
C. Da Ros ◽  
P. Pavan ◽  
F. Cecchi ◽  
D. Bolzonella

Waste activated sludge production and management plays an important role in wastewater treatment plants (WWTPs), especially from an economic point of view. One possible approach is the anaerobic co-digestion of waste activated sludge with others organic substrates in mesophilic and thermophilic conditions in order to exploit the spare volume of existing reactors, recover energy from biogas production, and obtain a fertilizer as final product. The anaerobic trials were carried out at pilot scale, applying two organic loading rates (2.8 and 4.5 kg chemical oxygen demand (COD)/(m3·d)) with a hydraulic retention time of 16 and 21 days. Among agro-wastes, wine lees were chosen because of their continuous availability throughout the year, and their high COD content (up to 200–300 g/l, 70% soluble, on average). The addition of wine lees to activated sludge determined a higher biogas production (best yield was 0.40 Nm3/kgCODfed) improving the energetic balance of the sludge line of the WWTP. The characterization of both substrates fed and digester effluents was carried out in terms of heavy metals; comparison with EC proposed limits showed that, due to high content of Cu in wine lees, the loading rate of this agro-waste should be limited to maintain good characteristics of final biosolids.


Author(s):  
Anatoliy Babaskin

Іintroduction. Despite the fact that a significant number of scientific publications by well-known Ukrainian authors are devoted to the issues of legal regulation of credit obligations, at the same time separate studies of banking legislation requirements on "acceptability of collateral" have not been conducted in Ukrainian civil science in recent years. This, taking into account the gradual alignment of banking legislation of Ukraine with the standards of Basel III, and Directive 2002/47 / EC of the European Parliament and of the Council of 6 June 2002 on financial collateral mechanisms, necessitates such scientific research. The aim of the article. On the basis of the analysis of the legislation of Ukraine, the legislation of the European Union, scientific advances in the sphere of civil law and banking legislation, in the context of the analysis of the banking legislation of Ukraine, it is safe for creditors. In order to achieve this goal: 1. Conduct an analysis of civil and legal species for the protection of crops for the subject of іх possible delivery to “acceptable safety” and vrahuvannya banks when opening a credit card. 2. Significantly "quasi-security", as viewed by the banking legislation in the form of "acceptable security" for credit cards. 3. Zdіysniti analysis of the approaches to the legislation of the EU in the field of protection from credit denominations. Results. The methodological basis of the study is general scientific and special legal methods of scientific knowledge. In particular, the dialectical method, the method of analysis and synthesis, the comparative law method, the functional method, the modeling method, etc. Conclusions. First, the banking legislation does not consider as "acceptable collateral" such types of collateral as penalty, surety, deposit, retention. Secondly, the banking legislation considers as "acceptable collateral" not only those specified in Part 1 of Art. 546 of the Civil Code of Ukraine types of security for performance of obligations (pledge, right of trust ownership, guarantee), and other types of security for performance of obligations provided by law or contract (reserve letter of credit, performing the function of financial guarantee, guarantees of public entities, guarantee payment), but also contractual constructions which do not concern types of maintenance of performance of obligations (repo agreements). Thus, the banking legislation considers collateral in credit operations from the economic point of view, according to which "acceptable collateral" is only such liquid collateral that guarantees the rapid recovery of the property of the creditor bank, which suffered damage due to default or improper performance of the counterparty loan obligation, as well as "quasi-collateral", if such is referred by banking legislation to "acceptable collateral". Third, the existence of rules in the banking legislation on the acceptability of collateral in no way affects the right of banks to use any type of collateral provided by law or contract, if the application of such is possible in credit relations, taking into account the legal nature of the relevant types. software. Fourth, the set of regulations of the National Bank of Ukraine on the acceptability of collateral can be considered as an institution of banking law, which includes as rules of civil law governing the types of collateral, other rules of contract law governing other "quasi-collateral" contractual constructions, as well as public-law special norms of banking legislation, which establish additional regulatory requirements for banks to ensure credit operations and calculate credit risk.


2015 ◽  
Vol 16 (1) ◽  
pp. 36-56
Author(s):  
Maria Elena Vera Villagran ◽  
L. Myriam Sagarnaga Villegas ◽  
Jose Salas Gonzalez ◽  
Juan Leos Rodriguez

This project looks for the relationship among variables influencing Mexican key lime supply and demand in the domestic and US market under the scenario of using a higher quantity of fertilizers as a strategy for responding against the threat of citrus greening (HLB). With the help of domestic and international databases from 2000 to 2012, a simultaneous equations model was built capturing behavioral and technical variables influencing supply and demand. The most important relationships among variables were price of the product and disposable income for the demand and use of fertilizers and exchange rate for the supply. This work gives the insight, from the economic point of view, that building a model including the right key variables will give a sense of the general structure of a market and the changes in stability due to a sanitary threat


Author(s):  
Lorin Niculae ◽  
◽  
Ana-Dora Matei ◽  
Alecsandru Vasiliu ◽  
◽  
...  

„House of Dawn” is the name of a project pertaining to the Arhipera trademark. It follows the same line of action of the group, namely the practice of social participatory architecture. The project concentrates on assuming the human capital that is in the limit situation of privation of shelter and tries to integrate it in a program that involves qualification and professional conversion in the construction field; the goal of the program is the „overnight” building of a minimal dwelling. The solutions for this category of persons in state of difficulty, situated at the extremity of the society, entails the configuration of varied typologies of minimal evolutive dwellings; as in the previous projects, the solutions aim at a democratic architecture obtained by using the „bottom‐up” model. In addition, the project proposes an ecological approach of the design, a durable development of the dwellings and puts a strong emphasis on the sustainability. From a topological point of view, the plots for building the dwellings for the homeless people will be connected with the existent urban tissue in order to achieve the social integration of the participants in the program; the choice of the plots focuses on unconventional spaces with regard to social habitation. A possibility that has been carefully considered from scratch is the reprocessing of unused urban spaces, including the recycling of the initial architectural function. Through the manifest of this program we propose the conversion of certain unfinished spaces of the totalitarian architecture of The People’s House/The Palace of Parliament into spaces for social dwellings destined for unsheltered people. In this particular case, the architectural recycling transforms the Totalitarianism into democracy and restores The People’s House to the people itself. The project is based on the norms of common law regarding the right to occupy the space meant for habitation. A family that is able to erect a house overnight on a plot on which it has no rights to is dignified to inhabit the respective space and proves to be useful from a social and economic point of view to the community that accepts it. The idea of the project is also sustained by a program of social integration of the beneficiaries and their inclusion in the labor market. The implementation of this type of social architecture is defined by efficiency, adaptability and flexibility and it’s centered both on the consolidation of the communitarian potential and on dwelling as an essential dimension of the humans. At the border of day and night, at the intersection of two spaces placed at the extremes, the Arhipera projects speak about opening the limit and abolishing it.


2017 ◽  
pp. 171-184 ◽  
Author(s):  
Александр (Aleksandr) Григорьевич (Grigor'evich) Топаж (Topazh) ◽  
Владимир (Vladimir) Александрович (Aleksandrovich) Вигонт (Vigont) ◽  
Любовь (Ljubov') Анатольевна (Anatol'evna) Хворова (Hvorova)

Article is devoted to the description and the analysis of the system-dynamic model of technological process of biogas production from multicomponent vegetable raw materials. A research objective – optimization of biogas production process from vegetable raw materials by methods of imitating modeling, finding of the optimal regimes of the simulated production cycle – the best ratio from the economic point of view between an exit of biomethane and rates of giving/replacement of the initial substratum depending on the composition of raw materials.In article models with a discrete and continuous cycle of production are considered, the description of the similar realization executed in the environment of multiapproach modeling of AnyLogic for model of technological process of anaerobic digestion of non-uniform multicomponent vegetable biomass is provided.The known stoichiometric model of production of biomethane is taken as a basis, her modification is made for a case of multicomponent raw materials (percentage division into conditional components – sugar, lignin and cellulose). Possibilities of modern software shells and environments of modeling in tasks of the complex analysis and optimization of the studied process are shown.During the conducted researches a row of non-trivial results on a choice of optimum parameters of an operation mode of the model bioreactor is received. For a case of the discrete process of up-dating of contents as parameters of optimization the frequency and a level of up-dating, and for the continuous flowing system – channel speed were selected.It is shown that the optimal values of the parameters from the point of view of the integrated output of the biomethane lie close to the cloud of critical acidification, which leads to the stoppage of the process. If the economic indicators are chosen as an optimization criterion, then we obtain optimal values of the parameters lying within the region of stable functioning of the model bioreactor.


2019 ◽  
Vol 33 (2) ◽  
pp. 161-181 ◽  
Author(s):  
Marina Grubišić ◽  
Mirela Ivančić Šantek ◽  
Božidar Šantek

Microalgae have been recognized as powerful phototrophic cell-factories whose applications range from biomass production for food and feed purposes to the production of high-value products and biofuels. Microalgae have been considered a source of functional ingredients, such as polyunsaturated fatty acids, polysaccharides, essential minerals, vitamins and bioactive peptides that can have positive effects on human and animal health. Besides having high nutritional value due to the high percentage of proteins in their composition, microalgae generate high-value products, such as pigments, polysaccharides, bio-hydrogen, and even bio-polyesters with plastic-like properties. Algal biomass that remains after product recovery can be used as forage, biofertilizer or feedstock for biogas production. This step in overall algal production is important from an economic point of view due to the reduction in production costs. This paper presents the detailed study of the biotechnologically most important microalgae strains, and the design principles of photobioreactors for their cultivation. In addition, the main existing and potential high-value products derivable from microalgae, as well as utilization of microalgae for phytoremediation and biogas production, were reviewed.


Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1276
Author(s):  
Angel Caravaca ◽  
Jesús González-Cobos ◽  
Philippe Vernoux

The phenomenon of “Non-Faradaic Electrochemical Modification of Catalytic Activity (NEMCA)” or “Electrochemical Promotion of Catalysis (EPOC)” has been extensively studied for the last decades. Its main strength, with respect to conventionally promoted catalytic systems, is its capability to modify in-situ the activity and/or selectivity of a catalyst by controlling the supply and removal of promoters upon electrical polarization. Previous reviews have summarized the main achievements in this field from both the scientific and technological points of view. However, to this date no commercial application of the EPOC phenomenon has been developed, although numerous advances have been made on the application of EPOC on catalyst nanostructures (closer to those employed in conventional catalytic systems), and on the development of scaled-up reactors suitable for EPOC application. The main bottleneck for EPOC commercialization is likely the choice of the right chemical process. Therefore, from our point of view, future efforts should focus on coupling the latest EPOC advances with the chemical processes where the EPOC phenomenon offers a competitive advantage, either from an environmental, a practical or an economic point of view. In this article, we discuss some of the most promising cases published to date and suggest future improvement strategies. The considered processes are: (i) ethylene epoxidation with environmentally friendly promoters, (ii) NOx storage and reduction under constant reaction atmosphere, (iii) CH4 steam reforming with in-situ catalyst regeneration, (iv) H2 production, storage and release under fixed temperature and pressure, and (v) EPOC-enhanced electrolysers.


2013 ◽  
Vol 79 (23) ◽  
pp. 7454-7465 ◽  
Author(s):  
Puntipar Sonthiphand ◽  
Eduardo Cejudo ◽  
Sherry L. Schiff ◽  
Josh D. Neufeld

ABSTRACTThe Grand River (Ontario, Canada) is impacted by wastewater treatment plants (WWTPs) that release ammonia (NH3and NH4+) into the river. In-river microbial communities help transform this ammonia into more oxidized compounds (e.g., NO3−or N2), although the spatial distribution and relative abundance of freshwater autotrophic ammonia-oxidizing prokaryotes (AOP) are not well characterized. This study investigated freshwater N cycling within the Grand River, focusing on sediment and water columns, both inside and outside a WWTP effluent plume. The diversity, relative abundance, and nitrification activity of AOP were investigated by denaturing gradient gel electrophoresis (DGGE), quantitative real-time PCR (qPCR), and reverse transcriptase qPCR (RT-qPCR), targeting both 16S rRNA and functional genes, together with activity assays. The analysis of bacterial 16S rRNA gene fingerprints showed that the WWTP effluent strongly affected autochthonous bacterial patterns in the water column but not those associated with sediment nucleic acids. Molecular and activity data demonstrated that ammonia-oxidizing archaea (AOA) were numerically and metabolically dominant in samples taken from outside the WWTP plume, whereas ammonia-oxidizing bacteria (AOB) dominated numerically within the WWTP effluent plume. Potential nitrification rate measurements supported the dominance of AOB activity in downstream sediment. Anaerobic ammonia-oxidizing (anammox) bacteria were detected primarily in sediment nucleic acids. In-river AOA patterns were completely distinct from effluent AOA patterns. This study demonstrates the importance of combined molecular and activity-based studies for disentangling molecular signatures of wastewater effluent from autochthonous prokaryotic communities.


Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4730 ◽  
Author(s):  
Steffen Limmer

In the literature, optimization-based approaches are frequently proposed for the control of electric vehicle charging. However, they are usually evaluated under simplifying assumptions and are not compared to more simple approaches. The present work compares optimization-based approaches with rule-based ones in a simple but realistic scenario, in which a certain limit for the total load has to be satisfied. The scenario is based on the situation at an office building in Germany. In simulation experiments, different control approaches are evaluated not only in terms of pure performance but also from an economic perspective. The results indicate that, although the optimization-based approaches outperform the rule-based approaches, they are not always the right choice from an economic point of view.


2019 ◽  
Vol 1 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Daniela Marotto ◽  
Angela Ceribelli ◽  
Piercarlo Sarzi Puttini

The advent of biological therapies in 2000s has represented a real revolution in the treatment of patients affected by rheumatic diseases, but biosimilars represent nowadays a further revolution both from an economic point of view and for the accessibility to treatment for rheumatic patients. The main scientific rheumatologic societies have clearly expressed themselves on the biosimilars topic, by highlighting how they represent a great opportunity to contain costs and treat more patients, and these advantages should be accepted by rheumatologists. The use of biosimilars in different European countries varies widely; in fact, in some of them their use is mandatory (at least in naïve patients), while in other countries it is only recommended. The knowledge and consequently the acceptance of biosimilars are different among patients, and this also depends on the correct medical information on this topic. As more and more biosimilars receive regulatory approval and reach the market, it is essential for healthcare professionals to have the right knowledge about them, so that they are properly transferred to their patients. Biosimilars are not identical to the reference product, and clinicians are particularly interested in the safety and effectiveness of switching from the biooriginator to the bio-similar in experienced patients. We will develop these aspects on biosimilars in the present manuscript, for an update on current guidelines in their use in rheumatic patients.


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