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1.
Water Sci Technol ; 89(7): 1879-1890, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619909

RESUMO

This study investigated the treatment of wastewater from tomato paste (TP) production using electrocoagulation (EC) and electrooxidation (EO). The effectiveness of water recovery from the pretreated water was then investigated using the membrane process. For this purpose, the effects of independent control variables, including electrode type (aluminum, iron, graphite, and stainless steel), current density (25-75 A/m2), and electrolysis time (15-120 min) on chemical oxygen demand (COD) and color removal were investigated. The results showed that 81.0% of COD and 100% of the color removal were achieved by EC at a current density of 75 A/m2, a pH of 6.84 and a reaction time of 120 min aluminum electrodes. In comparison, EO with graphite electrodes achieved 55.6% of COD and 100% of the color removal under similar conditions. The operating cost was calculated to be in the range of $0.56-30.62/m3. Overall, the results indicate that EO with graphite electrodes is a promising pretreatment process for the removal of various organics. In the membrane process, NP030, NP010, and NF90 membranes were used at a volume of 250 mL and 5 bar. A significant COD removal rate of 94% was achieved with the membrane. The combination of EC and the membrane process demonstrated the feasibility of water recovery from TP wastewater.


Assuntos
Grafite , Solanum lycopersicum , Poluentes Químicos da Água , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Alumínio , Eletrocoagulação/métodos , Água , Eletrodos , Resíduos Industriais/análise
2.
PLoS One ; 19(4): e0302176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635601

RESUMO

As one of the key materials used in the civil engineering industry, concrete has a global annual consumption of approximately 10 billion tons. Cement and fine aggregate are the main raw materials of concrete, and their production causes certain harm to the environment. As one of the countries with the largest production of industrial solid waste, China needs to handle solid waste properly. Researchers have proposed to use them as raw materials for concrete. In this paper, the effects of different lithium slag (LS) contents (0%, 10%, 20%, 40%) and different substitution rates of recycled fine aggregates (RFA) (0%, 10%, 20%, 30%) on the axial compressive strength and stress-strain curve of concrete are discussed. The results show that the axial compressive strength, elastic modulus, and peak strain of concrete can increase first and then decrease when LS is added, and the optimal is reached when the LS content is 20%. With the increase of the substitution rate of RFA, the axial compressive strength and elastic modulus of concrete decrease, but the peak strain increases. The appropriate amount of LS can make up for the mechanical defects caused by the addition of RFA to concrete. Based on the test data, the stress-strain curve relationship of lithium slag recycled fine aggregate concrete is proposed, which has a high degree of agreement compared with the test results, which can provide a reference for practical engineering applications. In this study, LS and RFA are innovatively applied to concrete, which provides a new way for the harmless utilization of solid waste and is of great significance for the control of environmental pollution and resource reuse.


Assuntos
Gerenciamento de Resíduos , Gerenciamento de Resíduos/métodos , Lítio , Resíduos Sólidos , Materiais de Construção , Reciclagem/métodos , Resíduos Industriais/análise
3.
Chemosphere ; 355: 141701, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508463

RESUMO

The purpose of this study is investigation of electrocoagulation (EC) as a treatment of municipal wastewater, integrating life cycle impact assessment (LCIA) for assessing its environmental performance of investigated treatment. The study evaluated the effectiveness of EC in removing physico-chemical and microbial parameters using aluminum (Al) and iron (Fe) electrodes in monopolar and bipolar modes. Bipolar arrangement of Al(-)/Al/Al/Al(+) electrodes achieved the highest removals: 70% COD, 72% BOD5 followed by complete elimination of total phosphorous, turbidity and microbial parameters. This treatment was subject to investigation of the influence of reaction time (t = 10-60 min) on removals at higher current density (CD = 3.33 mA/cm2). In order to reduce energy consumption, the same reaction time range was used with a reduced CD = 2.33 mA/cm2. Following removal efficiencies obtained: 47-72% COD (higher CD) and 53-78% (lower CD); 69-75% BOD5 (higher CD) and 55-74% CD (lower CD); 12-21% NH4- (higher CD) and 7-22% NH4- (lower CD). Total P, NO3- and NO2- compounds showed the same removals regardless the CD. Decrease in current density did not influence removals of total suspended matter, turbidity, salinity as well as microbial parameters. The bipolar arrangement of Al(-)/Al/Al/Al(+) electrodes, assuming a lower CD = 2.33 mA/cm2 and t = 30 min, was assessed with the Recipe 2016Midpoint (H) and USEtox v.2 LCIA methods to explore the environmental justification of using EC for wastewater treatment. The LCIA results revealed that the EC process significantly reduces water eutrophication and toxicity for freshwater and marine ecosystems, but has higher impacts in global warming, fossil fuel consumption, human toxicity, acidification, and terrestrial ecotoxicity due to high energy consumption. This can be mainly explained by the assumption in the study that the EC precipitate is dispersed to agricultural soil without any pre-treatment and material recovery, along with relatively high energy consumption during the process.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Humanos , Eliminação de Resíduos Líquidos/métodos , Ecossistema , Eletrocoagulação/métodos , Ferro , Eletrodos , Alumínio , Resíduos Industriais/análise
4.
Int J Biol Macromol ; 265(Pt 2): 131133, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537851

RESUMO

The low chrome uptake by collagen in the conventional tanning process leads to the pollution of the wastewater. Due to environmental concerns, leather scientists are already searching for innovative ways to produce pre-tanning agents as a high exhaustion chrome tanning auxiliary. Herein, a novel kind of pre-tanning agent is engineered by converting carboxymethyl cellulose (CMC) to oxidized carboxymethyl cellulose (OCMC) via the hydrogen peroxide process. FT-IR and carboxyl content analysis demonstrated the increase in carboxyl content after oxidation. After that, the obtained OCMC was utilized as a pre-tanning agent, resulting in a high exhaustion of chrome (92.76 %) which is 27.76 % more than conventional chrome tanning (65 %), and the amount of chrome in wastewater reduced to 7.24 %. The hydrothermal stability of wet-blue increased by increasing the uptake of chrome (Ts = 118 °C). The obtained crust leather represented excellent mechanical properties (Tensile strength: 305.68 kg/cm2; tear strength: 50 kg/cm) and desirable organoleptic properties. The environmental analysis signifies a significant step towards a cleaner and sustainable tanning process (COD = 1600, BOD5 = 560 mg/L) compared to the conventional chrome tanning process. Consequently, the obtained results offer a green pre-tanning agent to meet the requirements of the sustainable development of the leather industry.


Assuntos
Carboximetilcelulose Sódica , Curtume , Peróxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Resíduos Industriais/análise , Cromo
5.
Bull Environ Contam Toxicol ; 112(3): 46, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459996

RESUMO

Chlorinated benzenes (CBzs) are a group of organic pollutants, which have been industrially or unintentionally produced through various chemical and thermal processes. Studies on full congener profiles of CBzs in waste and environmental samples are relatively limited and not updated. In the present study, concentrations of 12 CBzs were determined in fly ash (FA) and bottom ash (BA) samples collected from one municipal waste incinerator (MWI) and one industrial waste incinerator (IWI) in northern Vietnam. Levels of Σ12CBzs were higher in bottom ash (median 25.3; range 1.59-45.7 ng/g) than in fly ash (median 7.30; range 1.04-30.0 ng/g). The CBz profiles were dominated by di- and tri-chlorinated congeners with the major congeners as 1,2,4-TCB, 1,2,3-TCB, 1,2-DCB, and 1,3-DCB. However, CBz profiles varied greatly between sample types and incinerators, implying differences in input materials, formation pathways, and pollutant behaviors. Incomplete combustion is possibly responsible for high levels of CBzs in industrial bottom ash. The emission factors of Σ12CBzs ranged from 21 to 600 µg/ton for fly ash and from 190 to 4570 µg/ton for bottom ash, resulting in annual emissions of about 6 and 3 g/year for the IWI and MWI, respectively. Our results suggest additional investigations on industrial emission and environmental occurrence of all 12 CBzs rather than solely focusing on regulated congeners like hexachlorobenzene and pentachlorobenzene.


Assuntos
Cinza de Carvão , Poluentes Ambientais , Cinza de Carvão/análise , Vietnã , Poluentes Ambientais/análise , Incineração , Resíduos Industriais/análise
6.
Waste Manag ; 180: 36-46, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38503032

RESUMO

As a by-product of the steelmaking industry, the large-volume production and accumulation of steel converter slag cause environmental issues such as land occupation and dust pollution. Since metal salts of unsaturated carboxylic acid can be used to reinforce rubber, this study explores the innovative application of in-situ modified steel slag, mainly comprising metal oxides, with methacrylic acid (MAA) as a rubber filler partially replacing carbon black. By etching the surface of steel slag particles with MAA, their surface roughness was increased, and the chemical bonding of metal methacrylate salt was introduced to enhance their interaction with the molecular chain of natural rubber (NR). The results showed that using the steel slag filler effectively shortened the vulcanization molding cycle of NR composites. The MAA in-situ modification effectively improved the interaction between steel slag and NR molecular chains. Meanwhile, the physical and mechanical properties, fatigue properties, and dynamic mechanical properties of the experimental group with MAA in-situ modified steel slag (MAA-in-situ-m-SS) were significantly enhanced compared with those of NR composites partially filled with unmodified slag. With the dosage of 7.5 phr or 10 phr, the above properties matched or even exceeded those of NR composites purely filled with carbon black. More importantly, partially replacing carbon black with modified steel slag reduced fossil fuel consumption and greenhouse gas emission from carbon black production. This study pioneered an effective path for the resourceful utilization of steel slag and the green development of the steelmaking and rubber industries.


Assuntos
Borracha , Resíduos Sólidos , Aço/química , Fuligem , Resíduos Industriais/análise , Metais , Metacrilatos
7.
J Environ Manage ; 357: 120713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552520

RESUMO

With the continuous advancement of urban renewal, the application of recycled aggregates (RA) is a win-win measure to solve the treatment of construction waste and provide the required building materials. However, the existence of a large amount of old adhesive mortar (OAM) makes it difficult for RA to equivalently replace natural aggregates (NA) due to their higher water absorption and crushing index, as well as a lower apparent density. From the published literature on enhancing RA, the most mature and easiest method for construction is physical enhancement technology. Therefore, through a review of recent related researches, this article summarizes and compares the modification effects of mechanical grinding technology, traditional heating and grinding technology, and microwave heating technology on the physical properties of RA, including water absorption, apparent density, and crushing value. The related modification mechanisms were discussed. Additionally, the impacts of different physical enhancement technologies on the environment and economy effects are assessed from the perspectives of carbon emissions and cost required during processing. Based on multi-criteria analysis, microwave heating technology is more efficient and cleaner, which is the most recommended in the future.


Assuntos
Resíduos Industriais , Reciclagem , Resíduos Industriais/análise , Reciclagem/métodos , Materiais de Construção , Água , Desempenho Físico Funcional
8.
Bioresour Technol ; 397: 130514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432546

RESUMO

Use of Grewia biopolymer as a natural coagulant aid was explored in a dual-coagulant system (conventional coagulant + biopolymer) for wastewater treatment. Such use not only improved turbidity removal efficiency over a wide pH range (5-9) but also helped reducing the concentration demand of inorganic coagulants by 25-50 %. Response surface methodology was employed for investigating the interaction between factors (initial pH, coagulant, and biopolymer concentration) affecting coagulation/flocculation of aqueous laterite suspension, and process optimization for more than 80 % turbidity removal in the desired final pH range (6-7). Mechanisms potentially involved in coagulation/flocculation using biopolymer was elucidated. Techno-economic assessment indicated the feasibility of pilot-scale production of the biopolymer and its use in wastewater treatment. This study demonstrates that Grewia biopolymer has the potential to be used as a coagulant aid and will help researchers select appropriate markets for further cost reduction and successful implementation of biopolymer-based wastewater treatment.


Assuntos
Grewia , Purificação da Água , Resíduos Industriais/análise , Biopolímeros , Floculação , Purificação da Água/métodos
9.
J Environ Manage ; 355: 120440, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38437740

RESUMO

The best solution to address environmental pollution caused by arsenic-containing hazardous waste is to prepare high-purity elemental arsenic from such waste. The key to this approach lies in the efficient separation of arsenic from various impurities. This paper presents a viable solution for producing high-purity elemental arsenic from arsenic-alkali slag, and the keylies in utilizing the selective precipitation of magnesium ammonium arsenate (MgNH4AsO4) to achieve efficient separation of arsenic from alkali, antimony, and other impurities. Thermodynamic analysis and hydrometallurgical condition experiments indicate that in complex alkaline arsenic-containing solutions, over 90% of arsenic components can selectively precipitate in the form of MgNH4AsO4. The content of arsenic in the resulting precipitate reaches approximately 30%, while the content of antimony is below 0.1%. This achieves efficient enrichment of arsenic and preliminary separation of impurities in complex arsenic-alkali slag. Thermodynamic analysis and pyrometallurgical condition experiments demonstrate that the precipitate of MgNH4AsO4 can be reduced to elemental arsenic with an arsenic content reaching 99.85%, and an antimony content as low as 0.05%. This achieves a profound separation of arsenic from impurities. Based on the research presented in this paper, a production line was established that enables the deep resource utilization of arsenic-alkali slag.


Assuntos
Arsênio , Arsênio/análise , Antimônio , Álcalis , Resíduos Industriais/análise
10.
Mar Pollut Bull ; 201: 116225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460435

RESUMO

The Huelva estuary is formed by the common mouths of the Odiel and Tinto Rivers, and inside this ecosystem is the biosphere reserve of the Odiel saltmarshes. This ecosystem has been historically affected by acid mine drainage (AMD) and by releases of pollutants from five phosphoric acid industrial plants and phosphogypsum (PG) waste stacks located in the area. This study carried out a comprehensive assessment of the environmental impact of the biosphere reserve of the Odiel saltmarshes. To this end, it was necessary to find a suitable sedimentary background (Piedras River in our case). To quantify this impact, several pollution indexes were used. According to the values reached by the indexes, this impact was classified as "serious" pollution for most trace elements, excepting the deepest layers, and "low-moderate" pollution for the 238U-series radionuclides, while no pollution for the 232Th-series and 40K radionuclides was found as expected.


Assuntos
Ecossistema , Poluentes Químicos da Água , Estuários , Resíduos Industriais/análise , Rios , Radioisótopos , Espanha , Monitoramento Ambiental , Poluentes Químicos da Água/análise
11.
Environ Sci Pollut Res Int ; 31(16): 23435-23461, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462563

RESUMO

This review critically evaluates the potential of Waste Foundry Sand (WFS) as a substitute for fine aggregate in concrete, conducting a comparative analysis of its physical and chemical properties against those of natural sand. The study synthesizes findings from various research experiments to determine concrete's most effective WFS replacement percentage. It compiles and analyzes data on how different WFS ratios affect concrete's mechanical properties, including modulus of elasticity and compressive strength. The review also consolidates research on the impact of WFS on concrete's workability, density, and flowability. A key finding is that WFS, categorized as a non-hazardous waste, possesses a diverse particle size distribution, rendering it suitable for recycling in various industrial applications.The study identifies that a 20%-30% replacement of WFS in concrete significantly improves properties such as voids, specific gravity, and density. However, it is essential to note that exceeding a 30% WFS replacement can result in increased carbonation depth and decreased resistance, primarily due to sulfur trioxide (SO3). Further observations indicate that incorporating higher levels of WFS in self-compacting concrete reduces its flowability and increases water permeability. Moreover, the review highlights the regulatory and classification challenges associated with using WFS, particularly its classification as waste, which hampers its widespread adoption in construction. In conclusion, the study recommends implementing End-of-Waste (EoW) regulations to facilitate sustainable recycling and environmental protection. Additionally, it includes a bibliometric analysis of foundry sand research spanning from 1971 to 2020, providing a comprehensive summary of the field's historical and recent developments.


Assuntos
Resíduos Industriais , Areia , Resíduos Industriais/análise , Dióxido de Silício , Reciclagem , Força Compressiva
12.
Mar Pollut Bull ; 201: 116281, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520998

RESUMO

Anthropogenic activities have increased the discharge of marine contaminants threatening marine life. Small gulfs, such as the Arabian Gulf, are vulnerable to accumulating potentially toxic elements in marine species due to slow water exchange. The concentration of 21 elements was determined in the tissues of Scomberomorus commerson from Umm Al Quwain (United Arab Emirates) and Bandar Abbas (Iran). Chromium, Copper, and Iron exceeded internationally established maximum permissible limits. Sites could not be distinguished based on Principle Component Analyses of elements. Elevated Cu and Cr in muscle are of concern to marine species as well as humans. Metal Pollution Index showed a significant difference between sites, with 20.34 % and 100 % of individuals suffering high metal toxicity and poor body conditions, respectively. The Arabian Gulf is experiencing an increase in discharge of industrial wastes. Implementation of strict policies to reduce discharge of toxic substances is required to protect marine organisms and humans.


Assuntos
Metais Pesados , Perciformes , Poluentes Químicos da Água , Humanos , Animais , Metais Pesados/análise , Peixes , Cobre/análise , Resíduos Industriais/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental
13.
J Environ Manage ; 355: 120350, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38422846

RESUMO

The difficulty of the microbial conversion process for the degradation of sotol vinasse due to its high acidity and organic load makes it an effluent with high potential for environmental contamination, therefore its treatment is of special interest. Calcium carbonate is found in great abundance and has the ability to act as a neutralizing agent, maintaining the alkalinity of the fermentation medium as well as, through its dissociation, releasing CO2 molecules that can be used by phototrophic CO2-fixing bacteria. This study evaluated the use of Rhodopseudomonas telluris (OR069658) for the degradation of vinasse in different concentrations of calcium carbonate (0, 2, 4, 6, 8 and 10% m/v). The results showed that calcium carbonate concentration influenced volatile fatty acids (VFA), alkalinity and pH, which in turn influenced changes in the degradation of chemical oxygen demand (COD), phenol and sulfate. Maximum COD and phenol degradation values of 83.16 ± 0.15% and 90.16 ± 0.30%, respectively, were obtained at a calcium carbonate concentration of 4%. At the same time, the lowest COD and phenol degradation values of 52.01 ± 0.38% and 68.21 ± 0.81%, respectively, were obtained at a calcium carbonate concentration of 0%. The data obtained also revealed to us that at high calcium carbonate concentrations of 6-10%, sotol vinasse can be biosynthesized by Rhodopseudomonas telluris (OR069658) to VFA, facilitating the degradation of sulfates. The findings of this study confirmed the potential for using Rhodopseudomonas telluris (OR069658) at a calcium carbonate concentration of 4% as an appropriate alternative treatment for sotol vinasse degradation.


Assuntos
Carbono , Rodopseudomonas , Eliminação de Resíduos Líquidos , Eliminação de Resíduos Líquidos/métodos , Dióxido de Carbono , Resíduos Industriais/análise , Carbonato de Cálcio , Fenóis , Reatores Biológicos
14.
Environ Sci Pollut Res Int ; 31(14): 20853-20880, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407704

RESUMO

Olive oil extraction has recently experienced a continuous increase due to its related beneficial properties. Consequently, large amounts of olive mill wastes (OMWs) derived from the trituration process are annually produced, causing serious environmental problems. The limited financial capabilities of olive mills make them usually unable to bear the high costs required for the disposal of their wastes. Alternatively, the valorization of OMWs within the framework of the so-called waste-to-resource concept and their recycling can represent a successful strategy for the implementation of circular economy model in the olive industry, which could have significant socioeconomic impacts on low-income Mediterranean countries. There is, however, no unique solution for OMWs valorization, due to the wide variety of the wastes' composition and their seasonal production. In this review, the potential of OMWs for being reused and the recent technological advances in the field of OMWs valorization are assessed. Special focus is given to the analysis of the advantages and limitations of each technology and to reporting the most significant issues that still limiting its industrial scale-up. The information collected in this review shows that OMW could be effectively exploited in several sectors, including energy production and agriculture. OMWs potential seems, however, undervalued, and the implementation of sustainable valorization strategies in large-scale remains challenging. More efforts and policy actions, through collective actions, encouraging subsidies, and establishing public-private collaborations, are still needed to reconcile research progress with industrial practices and encourage the large-scale implementation of the waste-to-resource concept in the olive sector.


Assuntos
Olea , Resíduos Industriais/análise , Azeite de Oliva , Agricultura
15.
Environ Sci Pollut Res Int ; 31(14): 20814-20852, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38400972

RESUMO

Resource utilization of construction and demolition (C&D) waste has great potential to significantly reduce the consumption of natural resources and improve the environment. Meanwhile, establishing a sound policy system and reducing production are the key ways to solve the problem of C&D waste. Numerous studies on C&D waste, recycled concrete aggregate (RA), and recycled aggregate concrete (RAC) have been reported in the literature, with few systematic summaries. From a global perspective, this paper assessed the current situation of C&D waste and the countermeasure of several major economies. Then, this paper systematically introduces the composition structure and characteristics of RA. Modification techniques from macro and micro perspectives of RA and its effect on RAC were also presented. Paper also reviews the environmental impacts of RA and RAC. The results showed that bonded mortar was the most significant defect of RA than natural aggregate (NA). Thus, RA weakened RAC's microstructure, workability, mechanical properties, and durability. The research on the modification of RA mainly focused on removing bonded mortar and enhancing bonded mortar containing physical or chemical methods. Enhancing bonded mortar was a more effective method than removing bonded mortar. Carbonation and microbially induced calcium carbonate precipitation were highly efficient and environmentally friendly for RA modification. Research progress in quantifying the environmental impacts associated with concrete from waste materials through the LCA methodology is presented. Suggestions and an outlook were given on the critical issues facing RA and RAC. We expect that this work can provide more technical support for C&D waste utilization.


Assuntos
Materiais de Construção , Reciclagem , Reciclagem/métodos , Meio Ambiente , Recursos Naturais , Resíduos Industriais/análise
16.
Environ Sci Pollut Res Int ; 31(13): 19795-19814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367113

RESUMO

Mill scale (MS) is considered to be a significant metallurgical waste, but there is no economical method yet to utilize its metal content. In this study, which covers various processes in several stages, the solution of iron in MS, which is the Iron and Steel Industry (I&SI) waste, as FeCl3 (MS-FeCl3) in the thermoreactor in the presence of HCl, was investigated. In the next step, the conditions for using this solution as a coagulant in the treatment of I&SI wastewater were investigated using the jar test. The results of the treated water sample were compared by chemical oxygen demand (COD), total suspended solids (TSS), color, and turbidity analyses using commercial aluminum sulfate (Al2(SO4)3) and FeCl3 (C-FeCl3). Additionally, heavy metal analyses were conducted, and the treatment performance of three coagulants was presented. Accordingly, while 2.0 mg/L anionic polyelectrolyte was consumed at a dosage of 4.05 mg/L Al2(SO4)3 at pH 7.0, 0.25 mg/L anionic polyelectrolyte was consumed at a dosage of 1.29 mg/L at pH 5.0 in the C-FeCl3 and MS-FeCl3 studies. Also, Fe, Cr, Mn, Ni, Zn, Cd, Hg, and Pb removal efficiencies were over 93.56% for all three coagulant usage cases. The results showed that the wastewater treatment performance of MS-FeCl3 by the recycling of MS, which is an I&SI waste, was at the same level as C-FeCl3. Thus, thanks to recycling, waste scale can be used as an alternative to commercial products for green production.


Assuntos
Cloretos , Compostos Férricos , Poluentes Químicos da Água , Purificação da Água , Eliminação de Resíduos Líquidos/métodos , Ferro/análise , Resíduos Industriais/análise , Polieletrólitos , Floculação , Poluentes Químicos da Água/análise
17.
Environ Monit Assess ; 196(3): 275, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363444

RESUMO

The economic development of a country directly depends upon industries. But this economic development should not be at the cost of our natural environment. A substantial amount of water is spent during paper production, creating water scarcity and generating wastewater. Therefore, the Pollution Control Board classifies this industry into red category. Water is used in different papermaking stages such as debarking, pulping or bleaching, washing, and finishing. The wastewater thus generated contains lignin and xenobiotic compounds such as resin acids, chlorinated lignin, phenols, furans, dioxins, chlorophenols, adsorbable organic halogens (AOX), extractable organic halogens (EOCs), polychlorinated biphenyls, plasticizers, and polychlorinated dibenzodioxins. Nowadays, several microorganisms are used in the detoxification of these hazardous effluents. Researchers have found that microbial degradation is the most promising treatment method to remove high biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater. Microorganisms also remove AOX toxicity, chlorinated compounds, suspended solids, color, lignin, derivatives, etc. from the pulp and paper mill effluents. But in the current scenario, mill effluents are known to deteriorate the environment and therefore it is highly desirable to deploy advanced technologies for effluent treatment. This review summarizes the eco-friendly advanced treatment technologies for effluents generated from pulp and paper mills.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos , Lignina , Descontaminação , Monitoramento Ambiental , Halogênios , Água , Resíduos Industriais/análise , Papel
18.
Int J Biol Macromol ; 261(Pt 2): 129922, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309403

RESUMO

Ecological retanning agent is an effective way to solve the pollution source of leather manufacturing industry. In this study, the gelatin from chrome-containing leather shavings in the leather industry was used to realize sustainable leather post-tanning. The gelatin hydrolysate (GH) coordinated with Zr4+ or Al3+ to prepare eco-friendly retanning agents GH-Zr and GH-Al. The successful coordination between GH and metal ions was characterized by FTIR and XPS. The retanning agents were characterized by FTIR curve-fitting and circular dichroism spectroscopy. The results showed that the conformation of the secondary structure of the polypeptide became ordered and stable after coordinating with the metal ions. The particle size and weight average molecular weight of the retanning agents were ~1700 nm and ~2100, respectively, measured by nanoparticle size analyzer and gel permeation chromatography (GPC). The retanning agents were applied to retanning of chrome tanned leather and glutaraldehyde tanned leather. The abundant free amino from retanning agents can consume the free formaldehyde. Meanwhile, retanning agents can effectively improve the multiple binding sites, resulting in favorable thickening rate (>110 %) and excellent dye and fatliquor absorption rate with ~99.91 % and ~93.18 %. Thus, this strategy can provide a viable choice for solid leather waste and sustainable development of the leather industry.


Assuntos
Gelatina , Curtume , Alumínio/análise , Zircônio , Íons/análise , Resíduos Industriais/análise
19.
J Environ Manage ; 354: 120317, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387346

RESUMO

Olive mill wastewater sludge (OMWS) represents a residual pollutant generated by the olive oil industry, often stored in exposed evaporation ponds, leading to contamination of nearby land and water resources. Despite its promising composition, the valorization of OMWS remains underexplored compared to olive mill wastewater (OMW). This study aims to identify potent native microbial species within OMWS suitable for bioremediation and its transformation into a high-value organic fertilizer. The microbial screening, based on assessing OMWS tolerance and phosphate solubilization properties in vitro, followed by a singular inoculation using a mixture of OMWS and rock phosphate (RP). Identification of FUN 06 (Galactomyces Geotrichum), a fungal species, employed as an inoculant in the treatment of sterile OMWS supplemented with RP. Results demonstrate that fungal inoculation notably diminished OMWS phytotoxicity while enhancing its physicochemical parameters, nutrient concentrations, and removal of toxic organic compounds by up to 90% compared to the control, and enhances plant growth, offering a sustainable approach to tackle environmental concerns. Additionally, metataxonomic analysis unveiled FUN 06's propensity to enhance the presence of microbial species engaged in pollutant degradation. However, higher RP dosage (10%) appeared to adversely affect bioprocess efficiency, suggesting a potential dose-related effect. Overall, FUN 06, isolated from OMWS evaporation ponds, shows promise for effective bioremediation and sustainable reuse. In fact, our results indicate that targeted microbial inoculation stands as an effective strategy for mitigating pollutants in OMWS, facilitating its conversion into a nutrient-rich organo-mineral fertilizer suitable for direct use, promoting its beneficial reuse in agriculture, thereby presenting a promising avenue for olive oil waste management.


Assuntos
Poluentes Ambientais , Olea , Águas Residuárias , Olea/química , Esgotos , Azeite de Oliva , Fertilizantes/análise , Poluentes Ambientais/análise , Fosfatos , Minerais , Resíduos Industriais/análise , Eliminação de Resíduos Líquidos/métodos
20.
Bioresour Technol ; 397: 130490, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403168

RESUMO

This study aimed to increase the value of brewers' spent grain (BSG) by using it as feedstock to produce lignocellulolytic enzymes and lactic acid (LA). Twenty-two fungal strains were screened for lignocellulolytic enzyme production from BSG. Among them, Trichoderma sp. showed the highest cellulase activity (35.84 ± 0.27 U/g-BSG) and considerably high activities of xylanase (599.61 ± 23.09 U/g-BSG) and ß-glucosidase (16.97 ± 0.77 U/g-BSG) under successive solid-state and submerged fermentation. The processes were successfully scaled up in a bioreactor. The enzyme cocktail was recovered and characterized. The maximum cellulase and xylanase activities were found at pH 5.0 and 50 °C, and the activities were highly stable at pH 4-8 and 30-50 °C. The enzyme cocktail was applied in simultaneous saccharification and fermentation of acid-pretreated BSG for LA production. The maximum LA obtained was 59.3 ± 1.0 g/L. This study has shown the efficient biovalorization of BSG, and this approach may also be applicable to other agro-industrial wastes.


Assuntos
Celulases , Ácido Láctico , Fermentação , Reatores Biológicos , Resíduos Industriais/análise , Grão Comestível/química
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