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1.
Environ Sci Pollut Res Int ; 30(55): 117464-117484, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37872342

RESUMO

The Nanyi Lake basin, located in the middle and lower reaches of the Yangtze River, is a crucial component of the Yangtze River ecosystem. Excessive phosphorus levels lead to eutrophication in rivers and lakes. This study aims to enhance the identification efficiency of key source areas for non-point source pollution of total phosphorus (TP) in the Nanyi Lake Basin and improve decision-making regarding the treatment of these areas. The study employs the InVEST model and utilizes GIS spatial hot spot analysis to identify key source areas of agricultural TP non-point source pollution. The accuracy of the InVEST model's simulation results was verified using the source list method. The findings indicate that paddy fields serve as the primary pollution source. TP non-point source pollution in Nanyi Lake is influenced by pollution sources, pollution load filtration rate, and potential TP runoff mass concentration. Different pollution sources correspond to distinct key source areas, and the pollution generated by these sources in different administrative regions, ultimately affecting the lake, varies as well. The InVEST model demonstrates great applicability in regions where agricultural TP is the primary pollution source. For the Nanyi Lake basin, which predominantly experiences agricultural TP non-point source pollution, a combination of the InVEST model and the source list method is recommended. The InVEST model serves as the primary tool, while the source list method supplements it. This approach not only compensates for any limitations of the InVEST model's simulation results but also avoids unnecessary economic waste. The outcomes of this study contribute to a deeper scientific understanding of TP pollution in the Nanyi Lake Basin. They also aid in effectively identifying key source areas and formulating appropriate measures based on the pollution characteristics, thereby providing guidance for non-point source pollution control in the basin.


Assuntos
Poluição Difusa , Poluentes Químicos da Água , Poluição Difusa/análise , Lagos , Monitoramento Ambiental/métodos , Fósforo/análise , Ecossistema , Nitrogênio/análise , Poluentes Químicos da Água/análise , Rios , China
2.
Environ Sci Pollut Res Int ; 30(42): 95875-95891, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37561306

RESUMO

The wastewater discharged from crude oil storage tanks (WCOST) contains high concentrations of salt and metal iron ions, and high chemical oxygen demand (COD). It belongs to "3-high" wastewater, which is difficult for purification. In this study, WCOST treatments were comparatively investigated via an advanced pretreatment and the traditional coagulation-microfiltration (CMF) processes. After WCOST was purified through the conventional CMF process, fouling occurred in the microfiltration (MF) membrane, which is rather harmful to the following reverse osmosis (RO) membrane unit, and the effluent featured high COD and UV254 values. The analysis confirmed that the MF fouling was due to the oxidation of ferrous ions, and the high COD and UV254 values were mainly attributable to the organic compounds with small molecular sizes, including aromatic-like and fulvic-like compounds. After the pretreatment of the advanced process consisting of aeration, manganese sand filtration, and activated carbon adsorption in combination with CMF process, the removal efficiencies of organic matter and total iron ions reached 97.3% and 99.8%, respectively. All the water indexes of the effluent, after treatment by the advanced multi-unit process, meet well the corresponding standard. The advanced pretreatment process reported herein displayed a great potential for alleviating the MF membrane fouling and enhanced the lifetime of the RO membrane system in the 3-high WCOST treatment.


Assuntos
Petróleo , Purificação da Água , Águas Residuárias , Eliminação de Resíduos Líquidos , Petróleo/análise , Filtração , Íons/análise , Ferro/análise , Osmose , Membranas Artificiais
3.
Environ Sci Pollut Res Int ; 30(18): 53807-53816, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36867338

RESUMO

Pre-treatment (oxidation) may induce potential modifications to microplastics (MPs), further affecting their behaviors and removal efficiency in drinking water treatment plants. Herein, potassium ferrate(VI) oxidation was tested as a pre-treatment for MPs with four polymer types and three sizes each. Surface oxidation occurred with morphology destruction and oxidized bond generation, which were prosperous under low acid conditions (pH 3). As pH increased, the generation and attachment of nascent state ferric oxides (FexOx) gradually became dominant, making MP-FexOx complexes. These FexOx were identified as Fe(III) compounds, including Fe2O3 and FeOOH, firmly attaching to the MP surface. Using ciprofloxacin as the targeted organic contaminant, the presence of FexOx enhanced MP sorption dramatically, e.g., the kinetic constant Kf of ciprofloxacin raised from 0.206 (6.5 µm polystyrene) to 1.062 L g-1 (polystyrene-FexOx) after oxidation at pH 6. The sinking performance of MPs was enhanced, especially for small MPs (< 10 µm), which could be attributed to the increasing density and hydrophilicity. For instance, the sinking ratio of 6.5 µm polystyrene increased by 70% after pH 6 oxidation. In general, ferrate pre-oxidation possesses multiple enhanced removals of MPs and organic contaminants through adsorption and sinking, reducing the potential risk of MPs.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Compostos Férricos/química , Microplásticos , Plásticos , Poliestirenos , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Ciprofloxacina
4.
J Hazard Mater ; 441: 129867, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36115091

RESUMO

The role of phosphorus in metal oxide catalysts is still controversial. The precise tuning of the acidic and redox properties of metal oxide catalysts for the selective catalytic reduction in NOx using NH3 is also a great challenge. Herein, CeO2 catalysts with different degrees of phosphorylation were used to study the balance between the acidity and redox property by promoting and inhibiting effects of phosphorus. CeO2 catalysts phosphorylated with lower phosphorus content (5 wt%) exhibited superior NOx reduction performance with above 90% NOx conversion during 240-420 °C due to the balanced acidity and reducibility derived from the highest content of Brønsted acid sites on PO43- to adsorb NH3 and surface adsorbed oxygen species. Plenty of PO3- over CeO2 catalysts phosphorylated with the higher phosphorus content (≥ 10 wt%) significantly disrupted the balance between the acidity and the redox property due to the reduced acid/redox sites, which resulted in the less active NOx species. The mechanism of different structural phosphorus species (PO43- and PO3-) in promoting or inhibiting the NOx reduction over CeO2 catalysts was revealed. This work provides a novel method for qualitative and quantitative study of the relationship between acidity/redox property and activity of catalysts for NOx reduction.


Assuntos
Cério , Fósforo , Ácidos , Amônia/química , Catálise , Cério/química , Oxirredução , Óxidos/química , Oxigênio
5.
Artigo em Inglês | MEDLINE | ID: mdl-36281981

RESUMO

The goal of this study was to assess the efficiency of antibiotic degradation applying different chemical treatment methods and their combinations. Thus, improvement in the efficiency of these methods when combined was quantified. The methods tested to degrade/mineralize the antibiotics amoxicillin (AMX) and ciprofloxacin (CIP) under different pH conditions (4, 7 and 10) were ultra-violet irradiation (UV254 nm), ultrasound (US), hydrogen peroxide (H2O2) and ozone (O3) alone and in combination. The results showed that individual methods were only partially efficient in the degradation/mineralization of antibiotics, except for ozonation at alkaline pH. In the combined methods, the best performance was obtained with US/UV/H2O2/O3 (pH 10, 20-min treatment), where the degradation rates for the antibiotics were 99.8% for CIP and 99.9% for AMX. For the mineralization efficiency the values obtained were 71.3% for CIP and 79.2% for AMX. The results of this study could contribute to the development and improvement of wastewater treatment aimed at avoiding the presence of residual antibiotics in the environment.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/análise , Oxirredução , Amoxicilina , Ciprofloxacina/química , Antibacterianos/química
6.
Chemosphere ; 308(Pt 3): 136328, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36130647

RESUMO

The transition towards a sustainable land management (SLM) needs for utilizing appropriate technologies for controlling soil pollution, and ensures the development of environmental, economic, technical, and social dimensions in region. Using these technologies for cleaning up soils polluted with oil and petroleum products in Behbahan city (in the southwest of Iran) is considered. The soil pollution control technologies (SPCTs) can assist local authorities, governments, investors, and developers to reduce climate change, mitigate soil, water, and air pollution and construct the sustainable communities. With the aim of balance between the issues in the context of sustainability policy, criteria (principles) including environmental, economic, technical, and social aspects are considered. The research takes into consideration the applicability of a novel multi-criteria decision-making approach namely complex spherical fuzzy set-based CODAS (Combinative distance-based assessment). The approach can be used to choose the suitable technology in a sustainable mode, considering the principles related to sustainability pillars. It comprises various technologies for soil pollution control and prioritizes technologies from the most to least as: Biorestoration technology, Excavation technology, Soil venting technology, Soil flushing, and Hydraulic barriers technology.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes do Solo , Poluição por Petróleo/prevenção & controle , Solo , Poluentes do Solo/análise , Tecnologia , Poluição da Água
7.
Animals (Basel) ; 11(5)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946294

RESUMO

It is essential to mitigate gaseous emissions that result from poultry and livestock production to increase industry sustainability. Odorous volatile organic compounds (VOCs), ammonia (NH3), hydrogen sulfide (H2S), and greenhouse gases (GHGs) have detrimental effects on the quality of life in rural communities, the environment, and climate. This study's objective was to evaluate the photocatalytic UV treatment of gaseous emissions of odor, odorous VOCs, NH3, and other gases (GHGs, O3-sometimes considered as by-products of UV treatment) from stored swine manure on a pilot-scale. The manure emissions were treated in fast-moving air using a mobile lab equipped with UV-A and UV-C lights and TiO2-based photocatalyst. Treated gas airflow (0.25-0.76 m3∙s-1) simulates output from a small ventilation fan in a barn. Through controlling the light intensity and airflow, UV dose was tested for techno-economic analyses. The treatment effectiveness depended on the UV dose and wavelength. Under UV-A (367 nm) photocatalysis, the percent reduction of targeted gases was up to (i) 63% of odor, (ii) 51%, 51%, 53%, 67%, and 32% of acetic acid, propanoic acid, butanoic acid, p-cresol, and indole, respectively, (iii) 14% of nitrous oxide (N2O), (iv) 100% of O3, and 26% generation of CO2. Under UV-C (185 + 254 nm) photocatalysis, the percent reductions of target gases were up to (i) 54% and 47% for p-cresol and indole, respectively, (ii) 25% of N2O, (iii) 71% of CH4, and 46% and 139% generation of CO2 and O3, respectively. The results proved that the UV technology was sufficiently effective in treating odorous gases, and the mobile lab was ready for farm-scale trials. The UV technology can be considered for the scaled-up treatment of emissions and air quality improvement inside livestock barns. Results from this study are needed to inform the experimental design for future on-farm research with UV-A and UV-C.

8.
Sci Total Environ ; 731: 138697, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32438085

RESUMO

Sediment phosphorus (P) is the main source of endogenous P for lake eutrophication. An in-situ combined technology for determination the removal effect of sediment P in all fractions was first developed using the novel modified maifanite (MMF) and submerged macrophytes in this study. MMF was synthesized using an acidification process (2.5 mol/L H2SO4) and then a calcination (400 °C) method. The morphology and structure of MMF were characterized by XRD, SEM, XPS, and BET. We tested the removal effects of sediment P by MMF and submerged macrophytes in combination and separately. The results demonstrated that the synergistic removal capacity of sediment P using MMF coupled with submerged macrophytes was higher than the sum of them applied separately. MMF could promote the submerged macrophytes growth and enhance the adsorption of extra P on MMF through root oxygenation and nutrient allocation. The microcosm experiment results showed that sediment from fMMF+V. spiralis exhibited the most microbial diversity and abundance among the sediment. The combination of MMF and submerged macrophytes increased the Firmicutes abundance and decreased the Bacteroidetes. These results indicated that adsorption-biological technology can be regarded as a novel and competitive technology to the endogenous pollution control in eutrophic shallow lakes.


Assuntos
Lagos , Fósforo , Adsorção , Eutrofização , Sedimentos Geológicos
9.
Environ Pollut ; 252(Pt B): 1464-1475, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31265957

RESUMO

In this study, a proposed integrated high-gravity technology for air pollution control, CO2 capture, and alkaline waste utilization was comprehensively evaluated from engineering, environmental, and economic perspectives. After high-gravity technology and coal fly ash (CFA) leaching processes were integrated, flue gas air emissions removal (e.g., sulfate dioxide (SO2), nitrogen oxides (NOx), total suspended particulates (TSP)) and CO2 capture were studied. The CFA, which contains calcium oxide and thus, had high alkalinity, was used as an absorbent in removing air pollution residues. To elucidate the availability of technology for pilot-scale high-gravity processes, the engineering performance, environmental impact, and economic cost were simultaneously investigated. The results indicated that the maximal CO2, SO2, NOx, and TSP removal efficiencies of 96.3 ±â€¯2.1%, 99.4 ±â€¯0.3%, 95.9 ±â€¯2.1%, and 83.4 ±â€¯2.6% were respectively achieved. Moreover, a 112 kWh/t-CO2 energy consumption for a high-gravity process was evaluated, with capture capacities of 510 kg CO2 and 0.468 kg NOx per day. In addition, the fresh, water-treated, acid-treated, and carbonated CFA was utilized as supplementary cementitious materials in the blended cement mortar. The workability, durability, and compressive strength of 5% carbonated CFA blended into cement mortar showed superior performance, i.e., 53 MPa ±2.5 MPa at 56 days. Furthermore, a higher engineering performance with a lower environmental impact and lower economic cost could potentially be evaluated to determine the best available operating condition of the high-gravity process for air pollution reduction, CO2 capture, and waste utilization.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Compostos de Cálcio/química , Dióxido de Carbono/química , Recuperação e Remediação Ambiental/métodos , Gravitação , Óxidos/química , Carbonatos/química , Carvão Mineral/análise , Cinza de Carvão/química , Óxidos de Nitrogênio
10.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3876-3883, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30453712

RESUMO

In order to analyze the law of membrane permeation of different alkaloids, seven traditional Chinese medicine alkaloids with different parent nucleus and substituent structures, including berberine, palmatine, sinomenine, matrine, oxymatrine, sophoridine, and tetrandrine, were prepared into the simulated solution with same molar concentration, and the membrane penetrating experiments with membrane RC1K and membrane RC5K were carried out. The dynamic transmittance, the total transmittance and the total adsorption rate of each substance were measured, and the scanning electron microscopy (SEM) images of the membrane surface before and after the membrane experiment were considered to predict and analyze the reason of differences in dynamic transmittance of different alkaloids. The results showed that there were significant differences in the dynamic transmittance of the chemical constituents of different alkaloids during penetrating the two membranes. The contamination degree on the surface of the membrane material was also different. The transmittance of the same compound through the RC5K membrane was larger than that through RC1K membrane. Within a certain range, the smaller the pore size of the membrane, the better the selective screening effect on the chemical constituents of traditional Chinese medicine. All the membrane surfaces were less polluted. The difference in transmittance between different substances on the same membrane showed a positive correlation with the difference in structural complexity, providing an experimental basis for the surface modification design in contamination control of membrane materials. In the design of membrane modified material, the surface properties of the membrane can be improved by grafting different polar groups, thereby changing the adsorption characteristics of the membrane surface. The pore size was designed accordingly to achieve the high transmittance and low pollution of the corresponding compounds.


Assuntos
Alcaloides de Berberina/química , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Permeabilidade
11.
J Environ Manage ; 226: 95-105, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30114577

RESUMO

In the present study, two synthesis methods of nanocomposites-one involving a mixture of biomass and the other using chemical modification were investigated to evaluate practical application of green approach in pollution control, specifically for water and wastewater treatment. Newer multifunctional superparamagnetic nanocomposites using biomaterials such as unripened fruit of Cassia fistula (Golden shower) and Aloe vera were developed as an example of green approach while chemical modification was illustrated using n-octanol. Two specific model applications were studied for the developed materials-dye removal (Methyl Blue and Congo Red) and disinfection-demonstrating antimicrobial property. To elucidate the multifunctional character, the texture, morphology and composition of the prepared bionanocomposites were studied. The surface area values were 6.2 and 9.8 m2/g for Aloe vera and octanol based nanocomposites while the average pore diameters were 1.79 nm and 5.7 nm respectively, indicating presence of highly developed micropores in the first material having a honeycomb shape and the later showing excellent staircase type formation with larger pores. A very high dye removal to the extent of 100% was obtained that can be attributed largely to the functionalities imparted from Cassia fistula compared to ingredients from Aloe vera and octanol. The nanomaterials could be completely separated with absolute ease by applying simple magnetic field. Also, successful application of the developed materials in disinfection, removal of E. coli, was demonstrated with a very high efficiency of over 95%. The biomass derived nanocomposites exhibit excellent pollutant removal and disinfection properties, even at very low nanoparticle content; octanol based material indicating ∼5 times lowered cost, while the Aloe vera based bionanocomposites have potential for cost reduction to the extent of 10 times as compared to only magnetite nanoparticles, thereby highlighting techno-economical alternative in water and wastewater treatment.


Assuntos
Nanocompostos , Águas Residuárias , Biomassa , Escherichia coli , Água , Purificação da Água
12.
Environ Sci Pollut Res Int ; 25(24): 23595-23623, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29959736

RESUMO

Due to water scarcity challenges around the world, it is essential to think about non-conventional water resources to address the increased demand in clean freshwater. Environmental and public health problems may result from insufficient provision of sanitation and wastewater disposal facilities. Because of this, wastewater treatment and recycling methods will be vital to provide sufficient freshwater in the coming decades, since water resources are limited and more than 70% of water are consumed for irrigation purposes. Therefore, the application of treated wastewater for agricultural irrigation has much potential, especially when incorporating the reuse of nutrients like nitrogen and phosphorous, which are essential for plant production. Among the current treatment technologies applied in urban wastewater reuse for irrigation, wetlands were concluded to be the one of the most suitable ones in terms of pollutant removal and have advantages due to both low maintenance costs and required energy. Wetland behavior and efficiency concerning wastewater treatment is mainly linked to macrophyte composition, substrate, hydrology, surface loading rate, influent feeding mode, microorganism availability, and temperature. Constructed wetlands are very effective in removing organics and suspended solids, whereas the removal of nitrogen is relatively low, but could be improved by using a combination of various types of constructed wetlands meeting the irrigation reuse standards. The removal of phosphorus is usually low, unless special media with high sorption capacity are used. Pathogen removal from wetland effluent to meet irrigation reuse standards is a challenge unless supplementary lagoons or hybrid wetland systems are used.


Assuntos
Irrigação Agrícola , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Cidades , Nitrogênio , Fósforo , Reciclagem , Águas Residuárias/análise , Águas Residuárias/química , Purificação da Água
13.
J Environ Manage ; 222: 409-419, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29883876

RESUMO

Pollution caused by volatile organic compounds (VOCs) and odorous pollutants in the air can produce severe environmental problems. In recent years, the emission control of VOCs and odorous pollutants has become a crucial issue owing to the adverse effect on humans and the environment. For treating these compounds, biotrickling filter (BTF) technology acts as an environment friendly and cost-effective alternative to conventional air pollution control technologies. Besides, low concentration of VOCs and odorous pollutants can also be effectively removed using BTF systems. However, the VOCs and odorants removal performance by BTF may be limited by the hydrophobicity, toxicity, and low bioavailability of these pollutants. To solve these problems, this review summarizes the design, mechanism, and common analytical methods of recent BTF advances. In addition, the operating conditions, mass transfer, packing materials and microorganisms (which are the critical parameters in a BTF system) were evaluated and discussed in view of improving the removal performance of BTFs. Further research on these specific topics, together with the combination of BTF technology with other technologies, should improve the removal performance of BTFs.


Assuntos
Reatores Biológicos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos , Biodegradação Ambiental , Filtração , Gases
14.
Sci Total Environ ; 634: 205-213, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29627543

RESUMO

Eutrophication has become a severe environmental problem in some tributaries of the Three Gorges Reservoir (TGR) in China. A two-year field investigation of nutrients, oxygen stable isotopes (δ18O), and hydrogen stable isotopes (δD) was performed from January 2010 to December 2011 to determine the sources of nutrients in Xiangxi Bay (XXB). The results showed that nitrogen, phosphorus and silicon varied seasonally depending on hydrodynamic changes. The bottom-layer intrusive density current decreased nitrogen and silicon concentrations and increase phosphorus concentrations in XXB, while the middle-layer intrusive density current increased nitrogen and silicon concentrations and decrease phosphorus concentrations. The differences in δ18O and δD among the Yangtze River (YR), XXB and the region upstream of XXB were significant, and according to the tracer method, the estimated contribution ratios of nitrogen, phosphorus and silicon from the YR to XXB were much larger than those from the region upstream of XXB. These findings suggest that water quality in the TGR can be improved by reducing the pollution load throughout the upstream basin of the YR but not through decentralized efforts in only one or two tributary basins.


Assuntos
Monitoramento Ambiental , Eutrofização , Nitrogênio/análise , Fósforo/análise , Poluentes Químicos da Água/análise , Baías/química , China
15.
Artigo em Chinês | WPRIM | ID: wpr-775403

RESUMO

In order to analyze the law of membrane permeation of different alkaloids, seven traditional Chinese medicine alkaloids with different parent nucleus and substituent structures, including berberine, palmatine, sinomenine, matrine, oxymatrine, sophoridine, and tetrandrine, were prepared into the simulated solution with same molar concentration, and the membrane penetrating experiments with membrane RC1K and membrane RC5K were carried out. The dynamic transmittance, the total transmittance and the total adsorption rate of each substance were measured, and the scanning electron microscopy (SEM) images of the membrane surface before and after the membrane experiment were considered to predict and analyze the reason of differences in dynamic transmittance of different alkaloids. The results showed that there were significant differences in the dynamic transmittance of the chemical constituents of different alkaloids during penetrating the two membranes. The contamination degree on the surface of the membrane material was also different. The transmittance of the same compound through the RC5K membrane was larger than that through RC1K membrane. Within a certain range, the smaller the pore size of the membrane, the better the selective screening effect on the chemical constituents of traditional Chinese medicine. All the membrane surfaces were less polluted. The difference in transmittance between different substances on the same membrane showed a positive correlation with the difference in structural complexity, providing an experimental basis for the surface modification design in contamination control of membrane materials. In the design of membrane modified material, the surface properties of the membrane can be improved by grafting different polar groups, thereby changing the adsorption characteristics of the membrane surface. The pore size was designed accordingly to achieve the high transmittance and low pollution of the corresponding compounds.


Assuntos
Alcaloides de Berberina , Química , Medicamentos de Ervas Chinesas , Química , Medicina Tradicional Chinesa , Permeabilidade
16.
Bioresour Technol ; 233: 200-208, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28279913

RESUMO

To mitigate ammonia (NH3) emissions from pig production and understand dynamic emission profiles, reduced dietary crude protein (CP) with amino acid supplementation was studied with 720 pigs in a 12-room research building for 155days that covered from weaned to finishing stages. The pigs were divided into three 4-room groups and fed with 2.1-3.8% reduced CP (T1), 4.4-7.8% reduced CP (T2), and standard (control) diets, respectively. Compared with the control group, T1 and T2 decreased manure volumes and manure NH4+-N concentrations. Group-mean NH3 emission from the control group was 68.9gd-1AU-1 (AU=500kg live mass). Emissions from T1 (46.7gd-1AU-1) and T2 (29.8gd-1AU-1) were reduced by 33.0% and 57.2% (p<0.05), respectively. Dynamic peak NH3 emissions appeared during the third nursery phase for T1 and T2, but delayed to the first grower phase for the control group.


Assuntos
Amônia/metabolismo , Proteínas Alimentares/metabolismo , Aminoácidos , Ração Animal , Animais , Esterco , Sus scrofa , Suínos
17.
Waste Manag ; 58: 25-33, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27687077

RESUMO

A stepwise method for assessment of the HP 12 is proposed and tested with 49 waste samples. The hazard property HP 12 is defined as "Release of an acute toxic gas": waste which releases acute toxic gases (Acute Tox. 1, 2 or 3) in contact with water or an acid. When a waste contains a substance assigned to one of the following supplemental hazards EUH029, EUH031 and EUH032, it shall be classified as hazardous by HP 12 according to test methods or guidelines (EC, 2014a, 2014b). When the substances with the cited hazard statement codes react with water or an acid, they can release HCl, Cl2, HF, HCN, PH3, H2S, SO2 (and two other gases very unlikely to be emitted, hydrazoic acid HN3 and selenium oxide SeO2 - a solid with low vapor pressure). Hence, a method is proposed:For a set of 49 waste, water addition did not produce gas. Nearly all the solid waste produced a gas in contact with hydrochloric acid in 5 min in an automated calcimeter with a volume >0.1L of gas per kg of waste. Since a plateau of pressure is reached only for half of the samples in 5 min, 6 h trial with calorimetric bombs or glass flasks were done and confirmed the results. Identification of the gases by portable probes showed that most of the tested samples emit mainly CO2. Toxic gases are emitted by four waste: metallic dust from the aluminum industry (CO), two air pollution control residue of industrial waste incinerator (H2S) and a halogenated solvent (organic volatile(s) compound(s)). HF has not been measured in these trials started before the present definition of HP 12. According to the definition of HP 12, only the H2S emission of substances with hazard statement EUH031 is accounted for. In view of the calcium content of the two air pollution control residue, the presence of calcium sulphide (EUH031) can be assumed. These two waste are therefore classified potentially hazardous for HP 12, from a total of 49 waste. They are also classified as hazardous for other properties (HP 7, 10and14 for one of them, and HP 10and14 for the other one respectively). Given these results, it can be assumed that few common household and industrial waste will be classified hazardous only by HP 12.


Assuntos
Ecotoxicologia/métodos , Gases , Resíduos Perigosos , Resíduos Industriais , Alumínio , Cloro/química , União Europeia , Gases/análise , Gases/química , Resíduos Perigosos/análise , Resíduos Perigosos/classificação , Ácido Clorídrico/química , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/química , Incineração , Metalurgia/métodos , Resíduos Sólidos/análise
18.
Mar Pollut Bull ; 87(1-2): 88-97, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25152183

RESUMO

Appropriate increases in the "sink" of a landscape can reduce the risk of non-point source pollution (NPSP) to the sea at relatively lower costs and at a higher efficiency. Based on high-resolution remote sensing image data taken between 2003 and 2008, we analyzed the "source" and "sink" landscape pattern variations of nitrogen and phosphorus pollutants in the Jiulongjiang estuary region. The contribution to the sea and distribution of each pollutant in the region was calculated using the LCI and mGLCI models. The results indicated that an increased amount of pollutants was contributed to the sea, and the "source" area of the nitrogen NPSP in the study area increased by 32.75 km(2). We also propose a landscape pattern optimization to reduce pollution in the Jiulongjiang estuary in 2008 through the conversion of cultivated land with slopes greater than 15° and paddy fields near rivers, and an increase in mangrove areas.


Assuntos
Estuários , Rios , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , China , Monitoramento Ambiental/métodos , Modelos Teóricos , Nitrogênio/análise , Fósforo/análise
19.
Waste Manag Res ; 32(3): 221-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24616344

RESUMO

Thermal treatment of sewage sludge produces fly ash, also known as the air pollution control residue (APCR), which may be recycled as a component of artificial lightweight aggregates (ALWA). Properties of APCR are typical: high content of Ca, Mg, P2O5, as well as potential to induce alkaline reactions. These properties indicate that ALWA prepared with a high content of APCR may remove heavy metals, phosphorus, and ammonium nitrogen from wastewater with high efficiency. The aim of this preliminary study was to determine the optimal composition of ALWA for potential use as a filter media in wastewater treatment systems. Five kinds of ALWA were produced, with different proportions of ash (shown as percentages in subscripts) in mixture with bentonite: ALWA0 (reference), ALWA12.5, ALWA25, ALWA50, and ALWA100. The following parameters of ALWA were determined: density, bulk density, compressive strength, hydraulic conductivity, and removal efficiency of ions Zn(2+), NH4 (+), and PO4 (3-). Tests showed that ALWA had good mechanical and hydraulic properties, and might be used in wastewater filtering systems. Phosphates and zinc ions were removed with high efficiency (80-96%) by ALWA25-100 in static (batch) conditions. The efficiency of ammonium nitrogen removal was low, <18%. Artificial wastewater treatment performance in dynamic conditions (through-flow), showed increasing removal efficiency of Zn(2+), PO4 (3-) with a decrease in flow rate.


Assuntos
Cinza de Carvão/química , Reciclagem , Eliminação de Resíduos Líquidos/métodos , Compostos de Amônio , Filtração , Metais Pesados/química , Nitrogênio/análise , Fósforo/análise , Fósforo/química , Polônia , Esgotos/análise
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