scholarly journals Construction of floating treatment wetlands for remediation of polluted waters

2017 ◽  
pp. 1-12
Author(s):  
Nevena Čule ◽  
Aleksandar Lučić ◽  
Dragana Dražić ◽  
Vladan Popović ◽  
Milorad Veselinović ◽  
...  

Water regulation, integral water management and water conservation are one of the main tasks, set by an ecologically conscious society. A series of complex treatments are set in order to achieve the main goal in wastewater treatment, i.e. eliminating or reducing pollutants to a level that will not cause adverse effects to humans and the environment. The paper presents the construction of an efficient, environmentally friendly and economically justified biological system for the treatment of polluted urban waters. Research has shown that the proposed system with floating islands and algae was effective in removing various categories of pollutants from polluted river (organic and inorganic matter, heavy metals and pathogenic microorganisms), which indicated that the selected type of construction was appropriate. It was concluded that minor modifications in terms of cell coverage by floating islands could provide even greater removal of certain pollutants such as nitrogen, phosphorus and heavy metals.

2020 ◽  
Vol 12 (14) ◽  
pp. 5801
Author(s):  
Fan Wei ◽  
Munazzam Jawad Shahid ◽  
Ghalia S. H. Alnusairi ◽  
Muhammad Afzal ◽  
Aziz Khan ◽  
...  

The textile industry is one of the most chemically intensive industries, and its wastewater is comprised of harmful dyes, pigments, dissolved/suspended solids, and heavy metals. The treatment of textile wastewater has become a necessary task before discharge into the environment. The textile effluent can be treated by conventional methods, however, the limitations of these techniques are high cost, incomplete removal, and production of concentrated sludge. This review illustrates recent knowledge about the application of floating treatment wetlands (FTWs) for remediation of textile wastewater. The FTWs system is a potential alternative technology for textile wastewater treatment. FTWs efficiently removed the dyes, pigments, organic matter, nutrients, heavy metals, and other pollutants from the textile effluent. Plants and bacteria are essential components of FTWs, which contribute to the pollutant removal process through their physical effects and metabolic process. Plants species with extensive roots structure and large biomass are recommended for vegetation on floating mats. The pollutant removal efficiency can be enhanced by the right selection of plants, managing plant coverage, improving aeration, and inoculation by specific bacterial strains. The proper installation and maintenance practices can further enhance the efficiency, sustainability, and aesthetic value of the FTWs. Further research is suggested to develop guidelines for the selection of right plants and bacterial strains for the efficient remediation of textile effluent by FTWs at large scales.


2016 ◽  
Vol 2 (91) ◽  
pp. 17-21
Author(s):  
S. H. Korsun ◽  
N. I. Dovbash

The aim of the study was to establish changes in the physico-chemical and agrochemical characteristics of gray forest large-clay loamy soil, depending on the contamination of ecotopes by heavy metals. Methods. Field, laboratory, mathematical and statistical. Results. The results of the study of the soil of areas with an over-dimensioned content of heavy metals and the transformation of agrochemical characteristics of gray forest soil in the cultivation of corn for grain. It was established that under conditions of systematic application of mineral fertilizers in agrocenoses, an increase in the lead concentration to 100 mg/kg, cadmium to 2,0, zinc to 50 mg/kg in gray forest soil did not result in a decrease in the amount available forms of nitrogen, phosphorus, potassium by plants, compared with the natural background. Concentration of lead in the amount of 1000 mg/kg, cadmium – 20, zinc – 500 mg/kg marked an increase in exchange and hydrolytic acidity and loss of humus.


Author(s):  
Monika Hejna ◽  
Elisabetta Onelli ◽  
Alessandra Moscatelli ◽  
Maurizio Bellotto ◽  
Cinzia Cristiani ◽  
...  

Sustainable agriculture is aimed at long-term crop and livestock production with a minimal impact on the environment. However, agricultural practices from animal production can contribute to global pollution due to heavy metals from the feed additives that are used to ensure the nutritional requirements and also promote animal health and optimize production. The bioavailability of essential mineral sources is limited; thus, the metals are widely found in the manure. Via the manure, metallic ions can contaminate livestock wastewater, drastically reducing its potential recycling for irrigation. Phytoremediation, which is an efficient and cost-effective cleanup technique, could be implemented to reduce the wastewater pollution from livestock production, in order to maintain the water conservation. Plants use various strategies for the absorption and translocation of heavy metals, and they have been widely used to remediate livestock wastewater. In addition, the pollutants concentrated in the plants can be exhausted and used as heat to enhance plant growth and further concentrate the metals, making recycling a possible option. The biomass of the plants can also be used for biogas production in anaerobic fermentation. Combining phytoremediation and biorefinery processes would add value to both approaches and facilitate metal recovery. This review focuses on the concept of agro-ecology, specifically the excessive use of heavy metals in animal production, the various techniques and adaptations of the heavy-metal phytoremediation from livestock wastewater, and further applications of exhausted phytoremediated biomass.


2012 ◽  
Vol 65 (1) ◽  
pp. 76-99 ◽  
Author(s):  
K. Haarstad ◽  
H. J. Bavor ◽  
T. Mæhlum

A literature review shows that more than 500 compounds occur in wetlands, and also that wetlands are suitable for removing these compounds. There are, however, obvious pitfalls for treatment wetlands, the most important being the maintenance of the hydraulic capacity and the detention time. Treatment wetlands should have an adapted design to target specific compounds. Aquatic plants and soils are suitable for wastewater treatment with a high capacity of removing nutrients and other substances through uptake, sorption and microbiological degradation. The heavy metals Cd, Cu, Fe, Ni and Pb were found to exceed limit values. The studies revealed high values of phenol and SO4. No samples showed concentrations in sediments exceeding limit values, but fish samples showed concentrations of Hg exceeding the limit for fish sold in the European Union (EU). The main route of metal uptake in aquatic plants was through the roots in emergent and surface floating plants, whereas in submerged plants roots and leaves take part in removing heavy metals and nutrients. Submerged rooted plants have metal uptake potential from water as well as sediments, whereas rootless plants extracted metals rapidly only from water. Caution is needed about the use of SSF CWs (subsurface flow constructed wetlands) for the treatment of metal-contaminated industrial wastewater as metals are shifted to another environmental compartment, and stable redox conditions are required to ensure long-term efficiency. Mercury is one of the most toxic heavy metals and wetlands have been shown to be a source of methylmercury. Methyl Hg concentrations are typically approximately 15% of Hgt (total mercury). In wetlands polycyclic aromatic hydrocarbons (PAH), bisphenol A, BTEX, hydrocarbons including diesel range organics, glycol, dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyls (PCB), cyanide, benzene, chlorophenols and formaldehyde were found to exceed limit values. In sediments only PAH and PCB were found exceeding limit values. The pesticides found above limit values were atrazine, simazine, terbutylazine, metolachlor, mecoprop, endosulfan, chlorfenvinphos and diuron. There are few water quality limit values of these compounds, except for some well-known endocrine disrupters such as nonylphenol, phtalates, etc.


2017 ◽  
Vol 262 ◽  
pp. 466-470 ◽  
Author(s):  
Zhen Yuan Nie ◽  
Hong Chang Liu ◽  
Jin Lan Xia ◽  
Huan Liu ◽  
Yun Lu Cui ◽  
...  

Adaption to the energy substrates and heavy metals by bioleaching micoorganisms is the prerequisite for efficient microbe-mineral interaction in bioleaching process. It is known extracellular polymer substances (EPSs) take important role in mediating the adaption to and action on energy substrates and heavy metals. This report presents the evolution of compositions and contents of the major components of EPSs of the typical bioleaching microorganisms (Acidithiobacillus ferrooxidans, Leptospirillum ferriphilum, Sulfobacillus thermosulfidooxidans, and Acidianus manzaensis,) exposed to different energy substrates and heavy metal ions. These strains were acclimated firstly to Fe2+ substrate, and then on the substrates elemental sulfur (S0), pyrite and chalcopyrite, respectively. It was found that the major components of capsule and slime EPSs in terms of proteins, polysaccharides, as well as uronic acids were quite different in contents for the Fe2+-acclimated strains, and they even changed more when the Fe2+-acclimated strains were further acclimated to the other substrates. When exposed to heavy metals, all strains demonstrated much decrease in contents of capsule EPSs, and much increase in slime EPSs contents and the heavy metals were found to bound to the slime parts. It was for the first time the EPSs of the bioleaching strains were fractionated into capsule part and slime part, and it was also for the first time we found the differences in evolution of compositions and contents of the major organic components as well as the inorganic matter of capsule EPSs and slime EPSs when the bioleaching strains were exposed to different energy substrates and heavy metals.


2020 ◽  
Vol 21 (3) ◽  
Author(s):  
Justyna Baraniak ◽  
Małgorzata Kania-Dobrowolska ◽  
Aleksandra Górska ◽  
Marlena Wolek ◽  
Anna Bogacz

Dietary supplements are a wide group of products belonging to the food category. Their sales are still growing. The composition, appearance and the intended use of these products make them resemble drugs. Dietary supplements are designed to meet the specific requirements of different consumer groups. Many dietary supplements contain herbal substances or their preparations. The safety of the herbal material is particularly affected by its proper identification, the part of the plant used as well as the standardization of the extract for a specific biologically active compound. Regardless of the group of consumers for which these products are intended, the risks associated with taking dietary supplements may relate to their contamination with heavy metals, pesticide residues or pathogenic microorganisms. There may also be adulterated dietary supplements on the market, the real composition of which differs from the composition presented on the original packing. Furthermore, the presence of restricted hazardous substances, or limited substances on the product is undoubtedly dangerous to health.


2020 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Fahruddin Fahruddin ◽  
Slamet Santosa ◽  
Sareda .

Marine water which has been polluted by heavy metals such as lead (Pb) from port activities can affect marine life, however several microorganisms are able to adapt in polluted waters due to their resistant capabilities. The research aimed to obtain isolates bacterial which are resistant to Pb and to test their resistant ability. Bacterial isolation was obtained from sediment and seawater taken in Paotere Port, Makassar. The isolation of the resistant bacteria was done using nutrient agar media which contained 10 ppm of Pb. The growth of the bacteria was initially observed macroscopically and microscopically to determine type of the colony. Resistant test for each type of isolate was done by inoculating them on nutrient broth media which contained different concentration of Pb: 5 ppm, 10 ppm, 15 ppm, 20 ppm, 25 ppm, and a control. The test resulted in eight different isolates, five isolates from sediment samples and three from seawater samples. The results showed that each isolate has different degree of resistant toward Pb. Isolate IA1 has the higher resistant ability, and it was followed by isolate IS5.---Perairan laut tercemar logam berat timbal (Pb), yang bersumber dari aktifitas pelabuhan, dapat mengganggu kehidupan biota laut, namun sejumlah mikrorganisme mampu beradaptasi karena memiliki kemampuan resistan.  Penelitian ini bertujuan untuk memperoleh isolat bakteri yang resistan terhadap Pb dan menguji kemampuan resistansinya. Isolasi bakteri diperoleh dari sampel sedimen dan air laut dari Pelabuhan Paotere, Makassar.Untuk isolasi bakteri resistan menggunakan media nutrient agar yang megandung 10 ppm Pb. Bakteri yang tumbuh diamati secara makropskopis dan mikroskopis sebagai pendekatan awal untuk mengetahui jenis isolat. Uji resistansi dilakukan untuk setiap jenis isolat, yang diinokulasikan pada media nutrient broth pada konsentrasi Pb sebesar 5 ppm, 10 ppm, 15 ppm. 20 ppm, 25 ppm dan 0 ppm sebagai kontrol.  Hasilnya, diperoleh delapan jenis isolat yang berbeda, yaitu lima jenis isolat dari sampel sedimen dan tiga dari sampel air laut. Dari hasil uji memperlihatkan, bahwa setiap isolat memiliki kemampuan resistansi berbeda-beda terhadap Pb. Isolat IA1 kemampuan resistansinya lebih tinggi, kemudian isolat IS5.


Sign in / Sign up

Export Citation Format

Share Document