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Physico-chemical and agronomic results of soil remediation by In Situ Chemical Reduction applied to a chlordecone-contaminated nitisol at plot scale in a French Caribbean banana plantation
2020
Mouvet, Christophe | Collet, Bastien | Gaude, Jean-Marie | Rangon, Luc | Bristeau, Sébastien | Senergues, Mathilde | Lesueur-Jannoyer, Magalie | Jestin, Alexandra | Hellal, Jennifer | Woignier, Thierry
The In Situ Chemical Reduction (ISCR) process was tested in a nitisol in a French Caribbean banana plantation using five different soil amendments. The addition of 2.8% or 4.0% of Zero Valent Iron (ZVI; dw/dw, 2 different trial plots) in the 0–40-cm soil layer lowered the initial chlordecone (CLD) concentration by up to 74% or 69% in 37 days or 94 days, with 75% of the decrease achieved after only 21 or 24 days of treatment depending on the trial plot. The addition of commercially available Daramend® was also tested by applying the 6% dose (dw/dw) recommended by the manufacturer and using either the regular alfalfa-based product or a bagasse-based product specifically formulated for the study. Both significantly lowered CLD concentrations, but to a lesser extent than with the ZVI-only amendment. A bagasse-ZVI mixture prepared on site produced results slightly better than the two Daramend®. The percentage decreases in CLD concentrations were correlated with the negative redox potentials achieved. In all the trial plots, dechlorinated transformation products appeared in the soil and soil water as the CLD concentrations decreased, with H atoms replacing up to 4 and 7 of the 10 Cl atoms, respectively. None of these degradation products appeared to accumulate in the soil or soil water during the treatment. Instead, the reverse occurred, with an overall downward trend in their concentrations over time. The effects of ISCR treatment on agronomic and human health–related parameters were measured in three different crops. The radishes produced with some treatments were visually of lower quality or smaller in size than those grown in the control plots. Lower yields were observed for the cucumbers and sweet potatoes grown after applying the bagasse-based amendments. Mortality among cucumber seedlings was observed after treatment with ZVI only. Simple operational solutions should suffice to remedy these negative agronomic effects. As regards human health–related effects, the CLD concentrations in radishes grown with three of the amendments were significantly lower than in the two control plots and well below the maximum residue level (MRL), which was substantially exceeded in the radishes grown on untreated soil. For cucumbers, the treatments with regular Daramend® and with a local bagasse-ZVI mixture produced fruits with CLD below the MRL and also below the concentrations in one of the two control plots. As for the sweet potatoes, adding a bagasse-ZVI mixture had a significant positive effect by decreasing contamination below the levels in the two control plots and below the MRL.
Show more [+] Less [-]Insights into variations on dissolved organic matter of bauxite residue during soil-formation processes following 2-year column simulation
2022
Xue, Shengguo | Liu, Zheng | Fan, Jiarong | Xue, Rui | Guo, Ying | Chen, Wei | Hartley, William | Zhu, Feng
Bauxite residue, an industrial alkaline solid waste, has a low organic carbon content which hinders plant growth. Dissolved organic matter (DOM) drives many biogeochemical processes including carbon storage and soil formation in soils. Input of exogenous organic materials may provide organic carbon and accelerate soil formation processes in bauxite residue. However, the potential effects of ameliorants on the quantity and quality of DOM in bauxite residue are still poorly understood. Here, the integration of ultraviolet–visible (UV–Vis) spectra, fluorescence spectra, and parallel factor (PARAFAC) analysis were used to investigate the vertical characteristics of DOM in bauxite residue treated by PV (the combined addition of 2% phosphogypsum and 4% vermicompost, w/w) and BS (6% w/w including 4% bagasse and 2% bran) with 2-year column experiments. The content of DOM in untreated residues ranged from 0.064 to 0.096 g/kg, whilst higher contents of DOM were observed in PV (0.13 g/kg) and BS (0.26 g/kg) treatment. Meanwhile, with the increase of residue depth, the aromaticity and hydrophobic components of DOM in residue decreased, which indicated that the degree of humification of the treated residues in the upper layer was higher than that in the lower layer. Compared with BR, BS and PV treatment accumulated the related content of fulvic acid-like substance from 36.14% to 71.33% and 74.86%, respectively. The incorporation of vermicompost and biosolids increased the content of humic-like substances, whilst decreasing the content of protein-like substances in the surface layer, which may be due to the enrichment of the microbial community. During soil formation processes, the application of organic amendments reduced both salinity and alkalinity, enhanced microbial community diversity, and changed the quantity and quality of DOM in bauxite residue. These findings improve our understanding of the dynamics of DOM and response of DOM to soil formation processes in bauxite residue.
Show more [+] Less [-]Ball milled biochar effectively removes sulfamethoxazole and sulfapyridine antibiotics from water and wastewater
2020
Wong, Kam Sing | Zimmerman, Andrew R. | Chen, Hao | Gao, Bin
Release of antibiotics into the environment, which often occurs downstream of wastewater treatment plants, poses a human health threat due to the potential development of bacterial antibiotic resistance. In this study, laboratory experiments were conducted to evaluate the performance of ball milled biochar on the removal of two sulfonamide antibiotics, sulfamethoxazole (SMX) and sulfapyridine (SPY) from water and wastewater. Aqueous batch sorption experiment using both pristine and ball milled biochar derived from bagasse (BG), bamboo (BB) and hickory chips (HC), made at three pyrolysis temperatures (300, 450, 600 °C), showed that ball milling greatly enhanced the SMX and SPY adsorption. The 450 °C ball milled HC biochar and BB biochar exhibited the best removal efficiency for SMX (83.3%) and SPY (89.6%), respectively. A range of functional groups were produced by ball milling, leading to the conclusion that the adsorption of sulfonamides on the biochars was controlled by multiple mechanisms including hydrophobic interaction, π–π interaction, hydrogen bonding, and electrostatic interaction. Due to the importance of electrostatic interaction, SMX and SPY adsorption was pH dependent. In laboratory water solutions, the Langmuir maximum adsorption capacities of SMX and SPY reached 100.3 mg/g and 57.9 mg/g, respectively. When tested in real wastewater solution, the 450 °C ball milled biochar still performed well, especially in the removal of SPY. The maximum adsorption capacities of SMX and SPY in wastewater were 25.7 mg/g and 58.6 mg/g, respectively. Thus, ball milled biochar has great potential for SMX and SPY removal from aqueous solutions including wastewater.
Show more [+] Less [-]Emission characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans from industrial combustion of biomass fuels
2022
Zhang, Chunlin | Bai, Li | Yao, Qian | Li, Jiangyong | Wang, Hao | Shen, Liran | Sippula, Olli | Yang, Jun | Zhao, Jinping | Liu, Jun | Wang, Boguang
Although biomass fuel has always been regarded as a source of sustainable energy, it potentially emits polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study investigated PCDD/F emissions from industrial boilers fired with three types of biomass fuel (i.e., bagasse, coffee residue, and biomass pellets) via stack sampling and laboratory analysis. The measured mass concentrations of PCDD/Fs varied among the boilers from 0.0491 to 12.7 ng Nm⁻³ (11% O₂), with the calculated average international toxic equivalent quantity (I-TEQ) from 0.00195 to 1.71 ng I-TEQ Nm⁻³ (11% O₂). Some of them were beyond the limit value for municipal waste incineration. 2,3,4,7,8-PeCDF could be used as a good indicator of dioxin-induced toxicity of stack flue gases from biomass-fired boilers. The PCDFs/PCDDs ratios were more than 1, likely indicating the formation of dioxins in the boilers favored by de novo synthesis. The emission factor (EF) of total PCDD/Fs averaged 5.35 ng I-TEQ kg⁻¹ air-dry biomass (equivalent to 39.0 ng kg⁻¹ air-dry biomass). Specifically, the mean EF was 6.94 ng I-TEQ kg⁻¹ (52.6 ng kg⁻¹) for biomass-pellet-fired boiler, 11.8 ng I-TEQ kg⁻¹ (74.6 ng kg⁻¹) for coffee-residue -fired boiler, and 0.0277 ng I-TEQ kg⁻¹ (0.489 ng kg⁻¹) for bagasse-fired boilers. The annual PCDD/F emission was estimated to be 208 g I-TEQ in 2020 in China, accounting for approximately 2% of the total national annual emission of PCDD/Fs. The results can be used to develop PCDD/Fs emission inventories and offer valuable insights to authorities regarding utilizing biomass in industry in the future.
Show more [+] Less [-]A review on efficient electromagnetic interference shielding materials by recycling waste—a trio of land to lab to land concept
2021
Verma, Sarika | Mili, Medha | Dhangar, Manish | Jagatheesan, Krishnasamy | Paul, Sriparna | Bajpai, Harsh | Vedanti, Nimisha | Mallik, Jyotirmoy | Khan, Mohammed Akram | Bhargaw, Hari Narayan | Hashmi, Sayed Azhar Rasheed | Srivastava, Avanish Kumar
The materials used in electrical and electronic applications have great importance and broader applications, but they have severe electromagnetic interference (EMI). These materials have extensive applications in broadcasting, medical industries, research, defence sectors, communication and similar fields. The EMI can be addressed by using effective EMI shielding materials. This review presents a detailed, comprehensive description for making electromagnetic interference shielding material by recycling various wastes. It starts with highlighting the overview of electromagnetic interference shielding (EMI) and its theoretical aspects. It provides a comprehensive and detailed understanding of recent trends in the novel approaches towards fabricating EMI shielding from industrial waste, agricultural waste and other miscellaneous wastes. This paper critically reviews the works related to the recycling of wastes like red mud (waste from the aluminium refining industry), ground tyre rubber, tea waste (biowaste) from tea industries, bagasse (waste from sugar cane industry), peanut and hazelnut shells (agricultural waste), waste tissue paper and polyethylene and other miscellaneous wastes like hydrocarbon carbon black and ash for the fabrication of highly effective electromagnetic (EM) interference shielding materials. Highly effective results have been reported using red mud showing maximum efficiency of 51.4 dB in X-band range, various agricultural waste displaying reflection loss of up to − 87.117 dB (in the range 0.01 to 20 GHz) and miscellaneous waste giving EMI SE of 80 dB in X-band frequency. A separate section is dedicated to emphasizing future work and recommendations.
Show more [+] Less [-]Potential use of biomass and coal-fine waste for making briquette for sustainable energy and environment
2021
Balraj, Ambedkar | Krishnan, Jagannathan | Selvarajan, Keerthana | Sukumar, Keertthana
Biomass waste contributes 14% of the total global energy. And 15–20% of the coal-fine waste from coal mines are deposited in the rivers, ponds, etc., unused, which leads to resource wastage and environmental pollution. The present study aims utilizing biomass and coal-fine waste for producing biomass-coal briquettes without using a binding material. Three different average sizes 50, 134.3, and 199.7 μm of biomass mixture (bagasse, groundnut shell, and woodchips) and coal-fines were used to make different ratios of biomass and coal mixture briquettes. Then, it is subjected to proximate, scanning electron microscope/elemental (SEM/EDX) and thermo-gravimetric analysis (TGA) to understand its property. Proximate analysis results revealed that the biomass waste has the low ash, sensible fixed carbon, and high volatile matter content. A briquette of biomass: coal = 7:1 ratio 50-μm particle size case was chosen for SEM/EDX and TGA analysis since it holds reasonable fixed carbon value comparatively. SEM analysis revealed irregular surfaces, cracks, cavities and longitudinal cracks, veins distribution all around, ups and shallows on the surface and it is the most favorable condition for fuel combustion since oxidant reaches the core of the fuel with less resistant. TGA reconfirms the spontaneous burning characteristics of the entire volatiles and fixed carbon. EDX analysis shows that the carbon and potassium are the two major elements present in the tested briquettes.
Show more [+] Less [-]Catalase and Phosphatase Activities During Hydrocarbon Removal from Oil-Contaminated Soil Amended with Agro-Industrial By-products and Macronutrients
2017
del Carmen Cuevas-Díaz, María | Martínez-Toledo, Ángeles | Guzmán-López, Oswaldo | Torres-López, Cinthya P. | del C. Ortega-Martínez, Areli | Hermida-Mendoza, Lizbeth J.
Microbiological activities are essential in the bioremediation of polluted soils. The enzymatic activities of microorganisms are usually used as a biological indicator of soil health. The aim of this work was to observe the catalase, acid phosphatase (AcP), and alkaline phosphatase (AlP) activities in soil that was amended with agro-industrial by-products and macronutrients during the process of total petroleum hydrocarbon (TPH) removal. To this end, microcosm tests were performed with soil and agro-industrial by-products ratios of 100:2:2, for soil:sugarcane bagasse pith:filter cake mud (SSF); 100:2, for both soil:sugarcane bagasse pith (SS); and for soil filter cake mud (SF). The macronutrients—carbon, nitrogen, and phosphorus—in the experimental treatments were adjusted to 100:10:1 with a solution of NH₄NO₃ and K₂HPO₄. The best TPH removal (51.4%) was obtained with SSF at 15 days. In addition, a significant correlation was observed between TPH removal and AlP as well as AcP (r = 0.74, p < 0.0001; r = 0.70, p < 0.0107, respectively). Fungi growth was also correlated with both AlP (r = 0.97, p < 0.0001) and AcP (r = 0.95, p < 0.0001) activities. Besides, bacterial and fungi growth showed a correlation with TPH (r = 0.86, p < 0.001; r = 0.77, p < 0.0034, respectively). It could be said that the agro-industrial by-products and macronutrients contributed to pollutant removal from the oil-polluted soil at relatively short amount of time. In addition, the enzymatic activities were increased after the treatment; in this study, the high sensitivity enzyme was AlP, and it could be used as an indirect indicator of oil pollutant removal.
Show more [+] Less [-]Strength and durability performance of modified cement-based concrete incorporated immobilized bacteria
2022
Dhivakar Karthick, Mani | Rampradheep, Gobi Subburaj | Shankar, Subramaniam
Owing to the load bearing and the other external environmental factors, the defects in the concrete occur in the form of cracks and flaws which leads to the reduction in the durability characteristics. Generally, the bacteria-based autogenous healing is adopted to restore those cracks. The ureolytic bacteria used urea as a source of nitrogen and convert it to carbonate ions, and then carbonate ions react with calcium ions to induce calcium carbonate in the presence of water. In the present study, binary cement-based concrete containing different concentration of immobilized bacteria is investigated, and its performance is evaluated based on the strength and durability characteristics. The experimentation includes bagasse ash (< 45µ) and fly ash (Class C) in proportions partially blended with cement. External loads are stimulated to assess the mechanical properties of concrete. Rapid chloride penetration test of the concrete before the induction of cracks is also performed. By comparing the compression test results, the microbial concrete of 10⁵cells/mg shows greater compressive strength when compared with the microbial concrete of 10⁷cells/mg and also with the conventional concrete. SEM analysis and compression test results reveal 15% fly ash additives have accomplished microbial concrete. And also the test results indicate the potential of encapsulation using clay pellets and silica gel.
Show more [+] Less [-]Bagasse Activated Carbon with TETA/TEPA Modification and Adsorption Properties of CO2
2017
Wei, Jianwen | Lin, Zhifeng | He, Zeyu | Geng, Linlin | Liao, Lei
Bagasse activated carbon (AC) and the new type of activated carbon (KAC) prepared with reactivation method of ZnCl₂-KOH were modified with triethylenetetramine (TETA) and tetraethylenepentamine (TEPA). The as-modified adsorbents for CO₂ separation were investigated by thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), elemental analysis, N₂ adsorption–desorption, as well as scanning electron microscopy (SEM). When the content of amine group is 5%, the CO₂ adsorption quantity of TEPA-loaded adsorbents reaches the highest at 60 °C (3.62 mmol/g for KAC and 1.98 mmol/g for AC, respectively). With a more abundant pore structure, KAC is more suitable for amine modification and its adsorption capacity of CO₂ is higher than that of AC after amine modification. Cyclic adsorption–desorption tests showed satisfactory regenerations for the modified adsorbents. Compared with other adsorbents, such as activated carbon, microporous zeolite, and mesoporous molecular sieve reported in literature, the new adsorbent prepared from the by-product of sugar industry has good performance (1.05–3.14 mmol/g larger than those of others) under the same conditions (60 °C and 15% partial pressure). The results are expected to provide scientific basis for the practical application.
Show more [+] Less [-]Multidisciplinary Approaches to Handling Wastes in Sugar Industries
2016
Bhatnagar, Amit | Kesari, Kavindra Kumar | Shurpali, Narasinha
The global sugarcane production is about 1.91 billion tons annually and is concentrated in tropical regions, particularly in developing nations in Latin America and Asia. According to the UN Food and Agricultural Organization (FAO), there are over 100 countries producing sugarcane today. The increase in sugarcane production implies a proportional increase in sugar industry wastes. As a consequence of such increasing trend, sugar industries are facing severe environmental problems due to the lack of sustainable solutions for their waste management. Therefore, immediate attention is required to find a proper way of management to deal with sugar industry wastes and effluent in order to minimize environmental pollution and associated health risks. In this paper, different sources of solid and liquid wastes from sugarcane agriculture and associated sugar agro-industries are reviewed and valorization approaches of these different wastes are discussed. Some of the important resource recovery options from sugar industry wastes, which have been discussed in this review, include ethanol production, recovery of chemicals, use of bagasse and bagasse fly ash as adsorbents in water treatment and building materials. Technologies associated with the treatment of wastewater from sugar industries and efficient ways of utilization of this treated water in agriculture with special attention to measurement of crop water use efficiency are reviewed in view of our own research activities carried out in the past.
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