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Quality changes of aquifer a relating to plant production
1997
Belic, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia). Institut za uredjenje voda) | Belic, A. | Bugarski, R.
Neither soil nor water has very distinct function when seen in isolation. Therefore, analyses of water and soil can get real value only by their linkages. Taking into consideration irrigated land, water and soil interaction degree can cause different changes of soil, plants and aquifer A. All negative changes which are occur in the soil (in case of using unsuitable water quality for irrigation or applying of not rational fertilizers amount) have influence to the changes aquifer A quality. Interaction between soil and aquifer A are require investigation of groundwater quality changes relating to plant production, especially in irrigation. Intensity and type of aquifer A properties change, in case of different soil use in agricultural production, have been studying since 1991 at the Lysimetric Station Rimski Sancevi (Serbia, Yugoslavia). The results are point out satisfactory quality of aquifer A after irrigation with wastewater and well water, and applying of different mineral fertilizers amount. The soil capability to receive water with unsuitable quality, to influence their change and change of aquifer A quality as the final recipient, are showed by received results.
Afficher plus [+] Moins [-]Optimization of methyl orange removal from water by sorption on iron(II) hydroxide
1997
Karlovic, E. | Dalmacija, B. | Tamas, Z. | Ivancev-Tumbas, I. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za hemiju)
The work describes optimization on the process of separation of a synthetic dye, methyl orange, from water by sorption on iron(II) hydroxide, using response surface methodology. It was established that the optimum sorption conditions for dye removal on iron(II) hydroxide are: pH 9.1, iron(II) concentration 128 mg/l, dye concentration 10 mg/l, whereby the highest efficiency of dye removal is close to 90%.
Afficher plus [+] Moins [-]Analysis effect wastewater and sludge in maintenance drainage system on melioration area "Upper Danube" [Serbia, Yugoslavia]
1999
Pantelic, S. (Javno vodoprivredno preduzece "Srbijavode", Novi Sad (Yugoslavia). Vodoprivredni centar "Dunav") | Bozinovic, M. | Buncic, N.
Base characteristic melioration territory "Upper Danube" inclusion round about 1.4 million ha area in Backa and Banat (Serbia, Yugoslavia) are presented in this paper. Specification problem maintenance of the drainage of system to originate because of discharge wastewater and sludge in channel and suggest in decides these problems are considered.
Afficher plus [+] Moins [-]Catagorization of the Nadel river (channel) on the point of empty of waste waters coming from "Skrobara" [starch factory] - Jabuka [Serbia, Yugoslavia]
1999
Jovanovic, T. ("HIP-Azotara", Pancevo (Yugoslavia)) | Gajic, S. | Krstevski, M. | Denic, Z. | Tomic, B.
Upon the construction and introduction of overflow lagoons for gravitational precipitation, starch production plant wastewater drained into the river (channel) Nadel, satisfy quality conditions established for irrigation of crops which bare waters with high salinity.
Afficher plus [+] Moins [-]Anaerobic treatment of wastewaters from alcohol and yeast factories
1999
Klasnja, M. | Sciban, M. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Tehnoloski fakultet)
Alcohol and yeast production is the most important part of the biotechnological production in Yugoslavia, with annual production of 13 667 867 liters of absolute alcohol and of 20 947 490 kg of yeast in the year 1998. Large environmental load is produced by wastewaters from alcohol and yeast factories (512 000 P.E.), especially by alcohol stillage (BOD 40 000 - 50 000 mg/L). Anaerobic treatment is suitable process for treatment of alcohol stillage, and of yeast factory wastewater. In this paper, effects of treatment process (organic load reduction, energy of produced biogas) are discussed; and potential of anaerobic treatment os wastewaters from Yugoslavia's alcohol and yeast factories is reviewed.
Afficher plus [+] Moins [-]Huge quantities of microplastics are “hidden” in the sediment of China's largest urban lake—Tangxun Lake
2022
Shi, Mingming | Li, Rui | Xu, An | Su, Yewang | Hu, Tianpeng | Mao, Yao | Qi, Shihua | Xing, Xinli
Microplastics (MPs) pollution in Tangxun Lake, the largest urban lake in China, was investigated. The average MPs pollution in sediment (1.81 ± 1.75 × 10⁴ items kg⁻¹) is at a high level, while the MPs in lakeshore water (917.77 ± 742.17 items m⁻³) is in the middle to low level compared with existing studies, which is related to the government's protection. Fragments and fibers are the most common shapes in sediment and water, respectively. MPs size <1 mm dominates in the sediment, while the MPs in water has a larger size. The distribution of MPs in the inner lake shows that pellets tend to “hidden” in sediments. Suspected MPs are randomly selected for polymer detection by Micro-Raman microscopy. Polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET) are the most common polymer types in water, sediment and atmospheric deposition MPs samples. The input of wastewater, fishery and surrounding human activities are the main sources of MPs in sediment. Atmospheric deposition has a great impact on the distribution of MPs, while the contribution of surface runoff to lake MPs is not remarkable. In addition, MPs in sediments have exceeded the environmental carrying capacity. More attention should be focused on the sediment, where huge amounts of MPs are “hidden”.
Afficher plus [+] Moins [-]The screening of emerging micropollutants in wastewater in Sol Plaatje Municipality, Northern Cape, South Africa
2022
Oluwalana, Abimbola E. | Musvuugwa, Tendai | Sikwila, Stephen T. | Sefadi, Jeremia S. | Whata, Albert | Nindi, Mathew M. | Chaukura, Nhamo
Although pollutants pose environmental and human health risks, the majority are not routinely monitored and regulated. Organic pollutants emanate from a variety of sources, and can be classified depending on their chemistry and environmental fate. Classification of pollutants is important because it informs fate processes and apposite removal technologies. The occurrence of emerging contaminants (ECs) in water bodies is a source of environmental and human health concern globally. Despite being widely reported, data on the occurrence of ECs in South Africa are scarce. Specifically, ECS in wastewater in the Northern Cape in South Africa are understudied. In this study, various ECs were screened in water samples collected from three wastewater treatment plants (WWTPs) in the province. The ECs were detected using liquid chromatography coupled to high resolution Orbitrap mass spectrometry following Oasis HLB solid-phase extraction. The main findings were: (1) there is a wide variety of ECs in the WWTPs, (2) physico-chemical properties such as pH, total dissolved solids, conductivity, and dissolved organic content showed reduced values in the outlet compared to the inlet which confirms the presence of less contaminants in the treated wastewater, (3) specific ultraviolet absorbance of less than 2 was observed in the WWTPs samples, suggesting the presence of natural organic matter (NOM) that is predominantly non-humic in nature, (4) most of the ECs were recalcitrant to the treatment processes, (5) pesticides, recreational drugs, and analgesics constitute a significant proportion of pollutants in wastewater, and (6) NOM removal ranged between 35 and 90%. Consequently, a comprehensive database of ECs in wastewater in Sol Plaatje Municipality was created. Since the detected ECs pose ecotoxicological risks, there is a need to monitor and quantify ECs in WWTPs. These data are useful in selecting suitable monitoring and control strategies at WWTPs.
Afficher plus [+] Moins [-]Microplastics in surface sediments of a highly urbanized wetland
2022
Birami, Farideh Amini | Keshavarzi, Behnam | Moore, Farid | Busquets, Rosa | Zafarani, Seyed Ghasem Ghorbanzadeh | Golshani, Reza | Cheshmvahm, Hamidreza
This study investigates the incidence of MPs in surface sediment samples, collected from the Anzali Wetland, Gillan province, North of Iran. This natural habitat receives municipal wastewater effluents and hosts industries and recreational activities that could release plastic to the wetland. There is need for studies to understand MPs pollution in wetlands. A total of 40 superficial sediment samples were taken covering potential pollution hotspots in the wetland. The average level of MPs was 362 ± 327.6 MP/kg: the highest MPs levels were near the outlet of a highly urbanized river (Pirbazar River) (1380 MP/kg), which runs through Rasht city. This was followed by 1255 MP/kg where there was intense fishing, boating and tourism activities in the vicinity of Bandar-e Anzali city. Fibers were the most common type of MPs (80% of the total MPs detected). The MPs polluting the wetland were predominantly white/transparent (42%), and about 40% of them were >1000 μm. Polypropylene (PP) and polyethylene (PE) prevailed in MPs found. MPs were characterized with polarized light microscopy, Raman spectroscopy, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray spectroscopy. Microplastics levels were found to correlate significantly (p > 0.7) with electrical conductivity (EC) and sand-size fraction of the sediments. Coarse-grained sediments presented large capacity to lodge the MPs. This study can be used to establish protection policies in wetlands and newly highlights the opportunity of intercepting MPs in the Anzali Wetland, which are generally >250 μm, before they fragment further.
Afficher plus [+] Moins [-]Simultaneous removal of COD and NH4+-N from domestic sewage by a single-stage up-flow anaerobic biological filter based on Feammox
2022
Ma, Ding | Wang, Jin | Li, Hao | Che, Jian | Yue, Zhengbo
In recent years, Feammox has made it possible to remove NH₄⁺-N under anaerobic conditions; however, its application in practical wastewater treatment processes has not been extensively reported. In this study, an up-flow anaerobic biological filter based on limonite (Lim-UAF) was developed to facilitate long-term and stable treatment of domestic sewage. Lim-UAF achieved the highest removal efficiency of chemical oxygen demand (COD) and NH₄⁺-N at a hydraulic retention time (HRT) of 24 h (Stage II). Specifically, the COD and NH₄⁺-N content decreased from 240.8 and 30.0 mg/L to about 7.5 and 0.35 mg/L, respectively. To analyze the potential nitrogen removal mechanism, the Lim-UAF was divided into three layers according to the height of the reactor. The results showed that COD and NH₄⁺-N removal had remarkable characteristics in Lim-UAF. More than 55.0% of influent COD was removed in the lower layer (0–30 cm) of Lim-UAF, while 60.2% of NH₄⁺-N was removed in the middle layer (30–60 cm). Microbial community analysis showed that the community structure in the middle and upper layers (60–90 cm) was relatively similar, but quite different from that of the lower layer. Heterotrophic bacteria were dominant in the lower layer, whereas iron-reducing and iron-oxidizing bacteria were enriched in the upper and middle layers. The formation of secondary minerals (siderite and Fe(OH)₃) indicated that the Fe(III)/Fe(II) redox cycle occurred in Lim-UAF, which was triggered by the Feammox and NDFO processes. In summary, limonite was used to develop a single-stage wastewater treatment process for simultaneously removing organic matter and NH₄⁺-N, which has excellent application prospects in domestic sewage treatment.
Afficher plus [+] Moins [-]Comparing with oxygen, nitrate simplifies microbial community assembly and improves function as an electron acceptor in wastewater treatment
2022
Zheng, Lei | Wang, Xue | Ren, Mengli | Yuan, Dongdan | Tan, Qiuyang | Xing, Yuzi | Xia, Xuefeng | Xie, En | Ding, Aizhong
Biochemical oxidation and reduction are key processes in treating biological wastewater and they require the presence of electron acceptors. The functional impact of electron acceptors on microbiomes provides strategies for improving the treatment efficiency. This research focused on two of the most important electron acceptors, nitrate and oxygen. Molecule ecological network, null model, and functional prediction based on high-throughput sequencing were used to analyze the microbiomes features and assembly mechanism. The results revealed nitrate via the homogeneous selection (74.0%) decreased species diversity, while oxygen via the homogeneous selection (51.1%) and dispersal limitation (29.6%) increased the complexity of community structure. Microbes that were more strongly homogeneously selected for assembly included polyphosphate accumulating organisms (PAOs), such as Pseudomonas and variovorax in the nitrate impacted community; Pseudomonas, Candidatus_Accumulibacter, Thermomonas and Dechloromonas, in the oxygen impacted community. Nitrate simplified species interaction and increased the abundance of functional genes involving in tricarboxylic acid cycle (TCA cycle), electron transfer, nitrogen metabolism, and membrane transport. These findings contribute to our knowledge of assembly process and interactions among microorganisms and lay a theoretical basis for future microbial regulation strategies in wastewater treatment.
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