Performance analysis of small wastewater treatment plants for mountain lodges

This paper presents the operation of seven small municipal wastewater treatment plants (WWTP) at mountain huts all over Slovenia. The studied WWTPs were selected as a representative sample based on inventory of all WWTPs of Alpine Association of Slovenia. Performance efficiency of selected WWTPs was carried out on the basis of 20 parameters obtained by field measurements and laboratory analyses of wastewater, which was sampled in winter and summer. Together, we carried out 200 hours of field research in the mountains.\ud Based on the assessment of the operation efficiency of selected WWTPs, proposals for their improvements were suggested. In addition to improvement proposals, the paper includes suggestions for Slovenian legislation complementation, proposals for engineers and planers, operators, producers, and suggestions for improvement and standardization of field measurements and sampling. This paper presents the first extensive survey of WWTP performance in the frame of Alpine Association of Slovenia and can serve as a basis for further studies of WWTPs at mountain huts, characterized by high fluctuations of influent wastewater.\ud The paper presents research, primarily based on field work, the key results and describes the main findings and unanswered questions. It also presents the key changes in the frame of new Regulation (2012) regarding mountain huts or non-permanent inhabited buildings.\u

Effect of advanced oxidation processes (AOPs) on the biodegradability of municipal wastewater for its reuse in the textile industry

Reuse of treated municipal wastewater to supplement part of fresh water is becoming more and more\ud important. However, treated water can contain some pollutants that cannot be successfully removed with\ud classical biological wastewater treatment processes. Aim of the study presented was to assess whether\ud advanced oxidation processes (AOPs) and special enzymes enhance biodegradation of municipal wastewater\ud and if treated municipal wastewater can be reused in the production process of textile industry. To test\ud biodegradability we used a small-scale pilot wastewater treatment plant (PWWTP) consisting of six parallel\ud bioreactors with suspended activated sludge (CAS type). Bioreactors were supplied with untreated municipal\ud wastewater, AOP-treated municipal wastewater and AOP-treated municipal wastewater with addition of\ud special enzymes. The results showed that AOPs contributed to better biodegradation while enzymes did not.\ud Municipal wastewater treated by a combination of AOP and biological treatment was not suitable for reuse\ud in the dyeing process, but could potentially be reused in some other processes in the textile industry

Vpliv naprednih oksidacijskih procesov (AOPs) na biorazgradljivost komunalne odpadne\ud vode za njeno ponovno uporabo v tekstilni industriji

Reuse of treated municipal wastewater to supplement part of fresh water is becoming more and more\ud important. However, treated water can contain some pollutants that cannot be successfully removed with\ud classical biological wastewater treatment processes. Aim of the study presented was to assess whether\ud advanced oxidation processes (AOPs) and special enzymes enhance biodegradation of municipal wastewater\ud and if treated municipal wastewater can be reused in the production process of textile industry. To test\ud biodegradability we used a small-scale pilot wastewater treatment plant (PWWTP) consisting of six parallel\ud bioreactors with suspended activated sludge (CAS type). Bioreactors were supplied with untreated municipal\ud wastewater, AOP-treated municipal wastewater and AOP-treated municipal wastewater with addition of\ud special enzymes. The results showed that AOPs contributed to better biodegradation while enzymes did not.\ud Municipal wastewater treated by a combination of AOP and biological treatment was not suitable for reuse\ud in the dyeing process, but could potentially be reused in some other processes in the textile industry

TiO

Approximately, 15% of the total textile colorant production is estimated to be lost during dyeing and processing of textile fibres. If left untreated, these wastewaters can represent a serious environmental threat. In the present paper a combination of photocatalytic and biological degradation of prepared textile wastewaters (simulation of real textile effluent) is presented. Samples have been monitored through the course of photocatalytic experiments: change in UV-VIS absorbance spectra and complete decolouration were achieved for all three tested dyed wastewaters; however, only partial COD removal was achieved with photocatalytic oxidation (PCOx) and photocatalytic ozonation (PCOz). Toxicity test (Vibrio fischeri) of untreated and pretreated (constructed wetland, CW) samples showed a decrease in toxicity values only for the red-dyed wastewater. Comparison of efficiency of PCOx and PCOz for decolouration and mineralization of three structurally different dyes (anthraquinone and two azo dyes) has been done. CW pretreatment caused faster decolouration and substantial COD removal in PCOx (up to 45%). Pretreatment also accelerated decolouration during PCOz, but it accelerated COD removal only in the case of red-dyed wastewater due to short irradiation times applied

Ugotavljanje indikatorskih bakterij fekalnega onesnaženja in prisotnosti vrste Escherichia coli, ki tvori encime β-laktamaze v črni vodi

The aim of this study was to identify and quantify faecal indicator bacteria in blackwater collected from a source separation unit and determine the amount of E. coli isolates resistant to antimicrobials and their potential to produce extended spectrum β-lactamases (ESβLs) and metallo-β-lactamases (MβLs), which hydrolyse the most important antibiotics used in clinical practice. Most of the isolates were resistant to amoxicillin with clavulanic acid (36.4 %), followed by ticarcillin with clavulanic acid (22.7 %) and tetracycline (18.2 %). ESβL-producing genes blaCTX-M and blaTEM were found in three (13.6 %) and four (18.2 %) E. coli strains, respectively, while MβL genes were found in two (9.1 %). By separating at source, this pilot study clearly shows that gastrointestinal bacteria of healthy people can be an important source of antibiotic resistance released into the environment through wastewaters. One way to prevent that is to treat wastewater with a combination of TiO2, UV light, or ozone, as successful methods to remove resistant bacteria and prevent their spread in the environment.V vzorcih črne vode, ki je ena od frakcij odpadne vode, smo ugotavljali prisotnost in število fekalnih indikatorskih bakterij, vključno z bakterijo Escherichia coli (E. coli). Pri osamljenih sevih E. coli smo ugotavljali njihovo odpornost proti izbranim antibiotikom in njihov potencial za tvorbo nekaterih β-laktamaz razširjenega spektra in metalo-β-laktamaz. Preizkušeni sevi so bili najpogosteje odporni proti amoksicilinu s klavulansko kislino (36,4 %), tikarcilinu s klavulansko kislino (22,7 %) in tetraciklinu (18,2 %). Nukleotidne sekvence za blaCTX-M in blaTEM smo našli pri treh (13,6 %) in štirih (18,2 %) sevih, medtem ko smo gene za izbrane metalo-β-laktamaze ugotovili pri dveh (9,1 %) sevih E. coli. Pilotna študija, z ločevanjem odpadne vode na viru nastanka, kaže, da so bakterije v prebavnem traktu zdravih ljudi lahko pomemben vir prenosa odpornosti proti antibiotikom v okolju preko odpadne vode. Eden izmed načinov za preprečevanje širjenja odpornosti proti antibiotikom je čiščenje odpadne vode z uporabo kombinacije TiO2, UV svetlobe in ozona, ki so se pokazale kot uspešne metode za odstranjevanje bakterij, odpornih proti antibiotikom

Aqu@teach—the first aquaponics curriculum to be developed specifically for university students

Aquaponic food production requires a broad spectrum of knowledge in order to understand and manage the processes involved, and for commercial aquaponics to develop its full potential, it will require an appropriately trained workforce. Devised in collaboration as an Erasmus+ Strategic Partnership for Higher Education, Aqu@teach covers the basics of aquaponics with a focus on transferable and entrepreneurial skills. The aquaponics curriculum can either be taught using blended learning—combining digital media and the internet with classroom formats that require the physical co-presence of the teacher and students—or as an e-learning course. The supplementary entrepreneurial skills module was devised on the basis of two surveys: of aquaponics companies around the world, in order to get a broad overview of the skills that are important in the early years of a business; and of European higher education institutions that teach subjects where aquaponics could be incorporated as an optional module. The entrepreneurial skills curriculum introduces the main processes involved in developing a business idea into a start-up company. All of the Aqu@teach resources—the e-learning modules, textbooks, module guides for students, curriculum guides for teachers, best practice guide for teaching aquaponics, and toolbox of innovative didactic practices—are open access

Towards a Cross-Sectoral View of Nature-Based Solutions for Enabling Circular Cities

A framework developed by the COST Action Circular City (an EU-funded network of 500+ scientists from 40+ countries; COST = Cooperation in Science and Technology) for addressing Urban Circularity Challenges (UCCs) with nature-based solutions (NBSs) was analyzed by various urban sectors which refer to different fields of activities for circular management of resources in cities (i.e., reducing use of resources and production of waste). The urban sectors comprise the built environment, urban water management, resource recovery, and urban farming. We present main findings from sector analyses, discuss different sector perspectives, and show ways to overcome these differences. The results reveal the potential of NBSs to address multiple sectors, as well as multiple UCCs. While water has been identified as a key element when using NBSs in the urban environment, most NBSs are interconnected and also present secondary benefits for other resources. Using representative examples, we discuss how a holistic and systemic approach could facilitate the circular use of resources in cities. Currently, there is often a disciplinary focus on one resource when applying NBSs. The full potential of NBSs to address multifunctionality is, thus, usually not fully accounted for. On the basis of our results, we conclude that experts from various disciplines can engage in a cross-sectoral exchange and identify the full potential of NBSs to recover resources in circular cities and provide secondary benefits to improve the livelihood for locals. This is an important first step toward the full multifunctionality potential enabling of NBSs

A review of nature-based solutions for resource recovery in cities

Our modern cities are resource sinks designed on the current linear economic model which recovers very little of the original input. As the current model is not sustainable, a viable solution is to recover and reuse parts of the input. In this context, resource recovery using nature-based solutions (NBS) is gaining popularity worldwide. In this specific review, we focus on NBS as technologies that bring nature into cities and those that are derived from nature, using (micro)organisms as principal agents, provided they enable resource recovery. The findings presented in this work are based on an extensive literature review, as well as on original results of recent innovation projects across Europe. The case studies were collected by participants of the COST Action Circular City, which includes a portfolio of more than 92 projects. The present review article focuses on urban wastewater, industrial wastewater, municipal solid waste and gaseous effluents, the recoverable products (e.g., nutrients, nanoparticles, energy), as well as the implications of source-separation and circularity by design. The analysis also includes assessment of the maturity of different technologies (technology readiness level) and the barriers that need to be overcome to accelerate the transition to resilient, self-sustainable cities of the future

The use of constructed wetland for dye-rich textile wastewater treatment

The objective of the present paper was to examine the treatment efficiency of constructed wetlands (CW) for the dye-rich textile wastewater with special focus on colour reduction. Preliminary, a series of dynamic experiments were performed in the CW model packed with gravel, sand, and zeolitic tuff on three synthetically-prepared wastewaters using chemically differ dyestuffs, auxiliaries and chemicals, in order to investigate the potential of low-cost materials as media for textile dye-bath wastewater treatment. The obtained results evidence that applied CW model reduces colour by up to 70%, and COD and TOC by up to 45%. Based on these results, the pilot CW with vertical (VF) and horizontal flow (HF) was constructed near textile factory mainly for cotton and cotton/PES processing with intention to treat real textile wastewater in-situ. It was designed for 1 m3/d, covering 80 m2, packed with sand and gravel, and planted with Phragmites australis. The average treatment efficiency of the CW for the selected pollution parameters were: COD 84%, BOD5 66%, TOC 89%, Ntotal 52%, Norganic 87%, NH4-N -331%, sulphate 88%, anion surfactant 80%, total suspended solids (TSS) 93%, and colour 90%, respectively. The results unequivocally proved that the CW could offer an optimal solution to meet the environmental legislation as well as requirements for effective and inexpensive textile wastewater treatment