Extremophilic Microalgae Galdieria Gen. for Urban Wastewater Treatment: Current State, the Case of “POWER” System, and Future Prospects

Over the past decades, wastewater research has increasingly focused on the use of microalgae as a tool to remove contaminants, entrapping nutrients, and whose biomass could provide both material and energy resources. This review covers the advances in the emerging research on the use in wastewater sector of thermoacidophilic, low-lipid microalgae of the genus Galdieria, which exhibit high content of protein, reserve carbohydrates, and other potentially extractable high-value compounds. The natural tolerance of Galdieria for high toxic environments and hot climates recently made it a key player in a single-step process for municipal wastewater treatment, biomass cultivation and production of energetic compounds using hydrothermal liquefaction. In this system developed in New Mexico, Galdieria proved to be a highly performing organism, able to restore the composition of the effluent to the standards required by the current legislation for the discharge of treated wastewater. Future research efforts should focus on the implementation, in the context of wastewater treatment, of more energetically efficient cultivation systems, potentially capable of generating water with increasingly higher purity levels.

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Dynamic simulation for upgrading of wastewater treatment plants—an assessment of treatment plant performance with regard to the EC-directive concerning urban wastewater treatment

Water Science & Technology ◽

10.2166/wst.1998.0342 ◽

1998 ◽

Vol 37 (9) ◽

pp. 73-79

Author(s):

A. Sintic ◽

T. Rolfs ◽

M. Freund ◽

E. Dorgeloh

Keyword(s):

Wastewater Treatment ◽

Dynamic Simulation ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

German Law ◽

Plant Performance ◽

Municipal Wastewater Treatment ◽

Urban Wastewater ◽

Urban Wastewater Treatment

This paper shows how the dynamic simulation of municipal wastewater treatment plants can be used for assessing the performance of a plant under different legal requirements. In this study, the situation is described, when it was uncertain, how the requirements of the German law (ARA-V 1991) would be adapted to the requirements given by the EC-directive concerning urban wastewater treatment (EC directive, 1991). The requirements of these two are compared to each other. A simulation study is described, in which the future results of a plant to be extended are calculated for the period of one year. It is shown that, concerning the effluent concentrations of ammonia and total nitrogen, this plant will be able to meet both laws.

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Efficiency of municipal wastewater treatment with membrane bioreactor

Journal of Water and Land Development ◽

10.2478/jwld-2019-0026 ◽

2019 ◽

Vol 41 (1) ◽

pp. 47-54

Author(s):

Magdalena Domańska ◽

Anna Boral ◽

Kamila Hamal ◽

Magdalena Kuśnierz ◽

Janusz Łomotowski ◽

...

Keyword(s):

Wastewater Treatment ◽

Membrane Filtration ◽

Municipal Wastewater ◽

High Efficiency ◽

Biological Membrane ◽

Treatment Plant ◽

Membrane Reactors ◽

Quality Analysis ◽

Treated Wastewater ◽

Municipal Wastewater Treatment

AbstractThe increasingly stringent requirements for wastewater treatment enforce the adoption of technologies that reduce pollution and minimize waste production. By combining the typical activated sludge process with membrane filtration, biological membrane reactors (MBR) offer great technological potential in this respect. The paper presents the principles and effectiveness of using an MBR at the Głogów Małopolski operation. Physicochemical tests of raw and treated wastewater as well as microscopic analyses with the use of the FISH (fluorescence in situ hybridization) method were carried out. Moreover, the level of electric energy consumption during the operation of the wastewater treatment plant and problems related to fouling were also discussed. A wastewater quality analysis confirmed the high efficiency of removing organic impurities (on average 96% in case of BOD5 and 94% in case of COD) and suspension (on average 93%).

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Bio-Methanol Production Using Treated Domestic Wastewater with Mixed Methanotroph Species and Anaerobic Digester Biogas

Water ◽

10.3390/w10101414 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1414 ◽

Cited By ~ 4

Author(s):

I-Tae Kim ◽

Young-Seok Yoo ◽

Young-Han Yoon ◽

Ye-Eun Lee ◽

Jun-Ho Jo ◽

...

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Cost Effective ◽

Treated Wastewater ◽

Culture Solution ◽

Municipal Wastewater Treatment ◽

Mineral Salts ◽

Methanol Production ◽

Municipal Wastewater Treatment Plants

The development of cost-effective methods, which generate minimal chemical wastewater, for methanol production is an important research goal. In this study, treated wastewater (TWW) was utilized as a culture solution for methanol production by mixed methanotroph species as an alternative to media prepared from commercial or chemical agents, e.g., nitrate mineral salts medium. Furthermore, a realistic alternative for producing methanol in wastewater treatment plants using biogas from anaerobic digestion was proposed. By culturing mixed methanotroph species with nitrate and phosphate-supplemented TWW in municipal wastewater treatment plants, this study demonstrates, for the first time, the application of biogas generated from the sludge digester of municipal wastewater treatment plants. NaCl alone inhibited methanol dehydrogenase and the addition of 40 mM formate as an electron donor increased methanol production to 6.35 mM. These results confirmed that this practical energy production method could enable cost-effective methanol production. As such, methanol produced in wastewater treatment plants can be used as an eco-friendly energy and carbon source for biological denitrification, which can be an alternative to reducing the expenses required for the waste water treatment process.

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Occurrence and fate of relevant substances in wastewater treatment plants regarding Water Framework Directive and future legislations

Water Science & Technology ◽

10.2166/wst.2012.943 ◽

2012 ◽

Vol 65 (7) ◽

pp. 1179-1189 ◽

Cited By ~ 40

Author(s):

S. Martin Ruel ◽

J.-M. Choubert ◽

H. Budzinski ◽

C. Miège ◽

M. Esperanza ◽

...

Keyword(s):

Wastewater Treatment ◽

Water Framework Directive ◽

Municipal Wastewater ◽

River Flow ◽

Wastewater Treatment Plants ◽

Quality Standard ◽

Treated Wastewater ◽

Municipal Wastewater Treatment ◽

Conventional Activated Sludge ◽

Treatment Processes

The next challenge of wastewater treatment is to reliably remove micropollutants at the microgram per litre range. During the present work more than 100 substances were analysed through on-site mass balances over 19 municipal wastewater treatment lines. The most relevant substances according to their occurrence in raw wastewater, in treated wastewater and in sludge were identified, and their fate in wastewater treatment processes was assessed. About half of priority substances of WFD were found at concentrations higher than 0.1 μg/L in wastewater. For 26 substances, potential non-compliance with Environmental Quality Standard of Water Framework Directive has been identified in treated wastewater, depending on river flow. Main concerns are for Cd, DEHP, diuron, alkylphenols, and chloroform. Emerging substances of particular concern are by-products, organic chemicals (e.g. triclosan, benzothiazole) and pharmaceuticals (e.g. ketoprofen, diclofenac, sulfamethoxazole, carbamazepine). About 80% of the load of micropollutants was removed by conventional activated sludge plants, but about two-thirds of removed substances were mainly transferred to sludge.

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A Mini-Review of Urban Wastewater Treatment in Greece: History, Development and Future Challenges

Sustainability ◽

10.3390/su12156133 ◽

2020 ◽

Vol 12 (15) ◽

pp. 6133

Author(s):

Charikleia Prochaska ◽

Anastasios Zouboulis

Keyword(s):

Wastewater Treatment ◽

Environmental Sustainability ◽

Rural Areas ◽

Wastewater Treatment Plants ◽

Treated Wastewater ◽

Septic Tank ◽

Urban Wastewater ◽

Tourism Sector ◽

Future Challenges ◽

Urban Wastewater Treatment

Although Greece has accomplished wastewater infrastructure construction to a large extent, as 91% of the country’s population is already connected to urban wastewater treatment plants (WWTPs), many problems still need to be faced. These include the limited reuse of treated wastewater and of the surplus sludge (biosolids) produced, the relative higher energy consumption in the existing rather aged WWTPs infrastructure, and the proper management of failing or inadequately designed septic tank/soil absorption systems, still in use in several (mostly rural) areas, lacking sewerage systems. Moreover, the wastewater treatment sector should be examined in the general framework of sustainable environmental development; therefore, Greece’s future challenges in this sector ought to be reconsidered. Thus, the review of Greece’s urban wastewater history, even from the ancient times, up to current developments and trends, will be shortly addressed. This study also notes that the remaining challenges should be analyzed in respect to the country’s specific needs (e.g., interaction with the extensive tourism sector), as well as to the European Union’s relevant framework policies and to the respective international technological trends, aiming to consider the WWTPs not only as sites for the treatment/removal of pollutants to prevent environmental pollution, but also as industrial places where energy is efficiently used (or even produced), resources’ content can be potentially recovered and reused (e.g., nutrients, treated water, biosolids), and environmental sustainability is being practiced overall.

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Cost of Urban Wastewater Treatment and Ecotaxes: Evidence from Municipalities in Southern Europe

Water ◽

10.3390/w11030423 ◽

2019 ◽

Vol 11 (3) ◽

pp. 423 ◽

Cited By ~ 1

Author(s):

Encarnación Moral Pajares ◽

Leticia Gallego Valero ◽

Isabel Román Sánchez

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Methodological Approach ◽

Economic Feasibility ◽

Wastewater Management ◽

Management Service ◽

Southern Europe ◽

Urban Wastewater ◽

Urban Wastewater Treatment

The principle of cost recovery established by the Water Framework Directive underlines the need for tax rates, which can raise enough revenue to finance the cost of treatments applied to wastewater. The objective of this research is to gain an understanding the different types of charges related to urban wastewater treatment that can be levied by the authorities responsible for this service. This paper also aims to determine whether these taxes contribute to guaranteeing the economic feasibility of the wastewater treatment plants. The proposed methodological approach is applied to 18 municipalities of a province in southern Europe in 2017. The results confirm that in most of these cases, the taxes levied do not guarantee adequate tax revenues to cover the running, maintenance and investment costs of municipal wastewater treatment plants. This situation leads to a lack of financial self-sufficiency in the wastewater management service, meaning that the imbalance between income and expenditure has to be covered by government subsidies. The results of this study will help guide authorities around the world that are in charge of managing urban wastewater treatment services.

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Application of SAC254 measurement for the assessment of micropollutant removal in the adsorptive treatment stage of a municipal wastewater treatment plant

Water Practice & Technology ◽

10.2166/wpt.2016.055 ◽

2016 ◽

Vol 11 (2) ◽

pp. 503-515 ◽

Cited By ~ 1

Author(s):

Annette Rößler ◽

Steffen Metzger

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Wastewater Treatment Plant ◽

Municipal Wastewater ◽

Treatment Plant ◽

Treated Wastewater ◽

Municipal Wastewater Treatment ◽

Adsorptive Treatment ◽

Micropollutant Removal ◽

Treatment Stage

In 2010, the Mannheim wastewater treatment plant was expanded with an adsorptive treatment stage to remove organic micropollutants (OMPs). Differences in the removal efficiencies of the OMPs investigated were determined over four years of operation by applying different powdered activated carbon (PAC) products and a constant volume-proportional dosing of 10 mg PAC/L. Possible influences on the removal efficiency are discussed here on the basis of the data obtained, exemplified for the analgesic diclofenac. The analyses show that the removal efficiency is influenced significantly by the spectral absorption coefficient (SAC) of the biologically treated wastewater at a wavelength of 254 nm (SAC254). Therefore, in order to ensure the constant treatment performance desired, the dosage of PAC should be adjusted to the measured SAC254 values. Moreover, as the SAC254 reduction correlates with the removal efficiency of OMPs, the additional determination of its reduction allows indirect control of the actual removal performance achieved. The SAC254 reduction can also be used for targeted control of the PAC dosage.

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Analysis of the investment costs in municipal wastewater treatment plants in Cundinamarca

DYNA ◽

10.15446/dyna.v82n192.44699 ◽

2015 ◽

Vol 82 (192) ◽

pp. 230-238 ◽

Cited By ~ 6

Author(s):

Juan Pablo Rodríguez Miranda ◽

César Augusto García-Ubaque ◽

Juan Carlos Penagos Londoño

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Analysis Data ◽

Design Flow ◽

Treated Wastewater ◽

Treatment Level ◽

Municipal Wastewater Treatment ◽

Process Data ◽

Scale Elasticity

Some of the most significant aspects in the selection of wastewater treatment plants are the investment costs, since they cross-linkthe treatment level, the quality of the raw wastewater, the design flow and the purpose of the treated wastewater. Through a multivariable exponential regression analysis, data from 51 projects of new treatment plants was analyzed, and from that process, data of cost scale elasticity was obtained, in slow growth, in comparison to the design flow for each of the treatment technologies analyzed.

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Sewage Flow Conditions in a Hydroponic Lagoon in Terms of Quality of Treated Wastewater

Water Air & Soil Pollution ◽

10.1007/s11270-021-05235-8 ◽

2021 ◽

Vol 232 (7) ◽

Author(s):

K. Marek ◽

K. Pawęska ◽

A. Bawiec ◽

J. Baran

Keyword(s):

Wastewater Treatment ◽

Cross Sections ◽

Suspended Solids ◽

Municipal Wastewater ◽

Pollutant Removal ◽

Treated Wastewater ◽

Municipal Wastewater Treatment ◽

Flow Conditions ◽

Wastewater Samples ◽

The Impact

AbstractThe aim of this study was to analyse the impact of velocity in the hydroponic lagoon used as the 3rd stage of municipal wastewater treatment on washing out of the particles suspended in the sewage as well as settled on the bottom of the hydroponic ditch. In order to analyse the flow velocity in the lagoon, 12 cross-sections were determined at points where the speed and motion of particles can change. Wastewater samples were taken in the summer month from each of the 12 sampling points (the depth of 0.1 m) and the basic physicochemical parameters of sewage were determined (BOD5, COD, TOC, TSS, turbidity). In selected cross-sections, a granulometric analysis of particles was made to determine the characteristics of suspended solids in the wastewater flow path. Based on the analysis, it was found that velocities in the lagoon during aeration can be ten times higher (0.070 m·s−1) than those assumed by designers (0.006 m·s−1). Such a large difference means that the sedimentation conditions assumed in the project cannot be met, which may result in an increase in the total suspended solids and organic matter concentrations at the outflow to the receiving water body. During the flow through the hydroponic ditch, the highest efficiency of pollutant removal was indicated for BOD5 — 88.7% and TSS — 80%, while the COD removal occurred with the lowest efficiency — 34.1%. Improving flow conditions as designed in the hydroponic lagoon technological project may increase the efficiency of wastewater treatment at the third stage of treatment.

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