Cleaner Materials最新文献_第3页

Recirculation of construction and demolition Waste: A case study of Danish producers and demolishers 建筑和拆除废物的再循环：丹麦生产商和拆除商案例研究

Cleaner Materials

Pub Date : 2024-11-14 DOI: 10.1016/j.clema.2024.100276

Julia Köhler, Fie Fredshavn Nielsen, Jakob Verstermark, Christian Thuesen

As resource scarcity increases, the construction industry recognizes the potential of Reverse Logistic Supply Chains (RLSC) for demolition waste. Implementing RLSC, however, lacks maturity and poses challenges due to the complexity of the construction industry. This paper is the first to investigate the critical interface between demolishers and producers. In particular, demolishers are crucial for the potential to valorize reclaimed construction wood as they are the gatekeepers of the materials. We apply an existing framework, conceptualized through a systematic literature review, to the case of a Danish shed producer and their collaboration with demolishers. Our data foundation includes qualitative data from semi-structured interviews with industry stakeholders and quantitative financial data on conventional as well as selective demolition. Through the analysis of material, information, and financial flows of reclaimed wood, this paper identifies inhibitors to these flows and reveals that producers can address the majority. Since responsibilities for reprocessing, transportation, and storage require clarification, making agreements for (1) reprocessing and (2) transportation, potentially facilitated by (3) a digital platform can support the producer in overcoming these inhibitors. Even though we show that selective demolition can be financially attractive for demolishers, our findings call for additional supportive regulation of tender practices. Further, we coin the concept of reversed value proposition as RLSC necessitate a reversed understanding of value creation. Overall, this paper contributes empirical evidence to the existing framework, extends it by adding inhibitors and flows, and suggests an extension with platform thinking to support the implementation of RLSC.

随着资源稀缺性的加剧，建筑行业认识到逆向物流供应链（RLSC）在处理拆除废物方面的潜力。然而，由于建筑行业的复杂性，反向物流供应链的实施还不够成熟，并面临着挑战。本文首次研究了拆除商和生产商之间的关键接口。特别是，拆除者对于再生建筑木材的价值潜力至关重要，因为他们是材料的守门人。我们将通过系统性文献综述概念化的现有框架应用于丹麦棚屋生产商及其与拆除商合作的案例中。我们的数据基础包括与行业利益相关者进行的半结构化访谈所获得的定性数据，以及有关传统拆除和选择性拆除的定量财务数据。通过对再生木材的材料流、信息流和资金流的分析，本文确定了这些流动的阻碍因素，并揭示了生产商可以解决的大多数问题。由于需要明确再加工、运输和储存的责任，因此在（1）再加工和（2）运输方面签订协议，并通过（3）数字平台的潜在促进作用，可以帮助生产商克服这些阻碍因素。尽管我们的研究表明，选择性拆除在经济上对拆除者很有吸引力，但我们的研究结果要求对招标行为进行额外的支持性监管。此外，我们还提出了 "反向价值主张 "的概念，因为有轨电车公司需要反向理解价值创造。总之，本文为现有框架提供了实证证据，通过增加抑制因素和流量对其进行了扩展，并提出了平台思维的扩展建议，以支持有偿租赁合同的实施。

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引用次数: 0

Effects of the surface properties and particle size of hydrated lime on desulfurization 熟石灰的表面特性和粒度对脱硫的影响

Cleaner Materials

Pub Date : 2024-11-12 DOI: 10.1016/j.clema.2024.100278

Karthikeyan Rajan , Duygu Kocaefe , Yasar Kocaefe , Jonathan Bernier , Yoann Robert , Yves Dargis

In the gas treatment center in smelters, hydrogen fluoride (HF) is separated from the outlet gases of electrolysis cells, which are used to produce aluminum from alumina. However, SO₂ largely remains in the effluent gas. Another method has to be developed to separate this gas which is harmful to the environment. In this study, semi-dry desulfurization of a SO₂ containing gas was performed at low SO₂ concentrations using hydrated lime [Ca(OH)₂] as a catalytic desulfurizer under specific humidity conditions. The low reaction temperature of 100 °C and minimal use of the Ca-based desulfurizer under 17 % relative humidity achieved more than 95 % removal of SO₂. The morphological changes and presence of sulfur in different lime samples were analyzed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Brunauer–Emmett–Teller (BET) analysis showed changes in the surface properties of hydrated lime after desulfurization. X-ray photoelectron spectroscopy (XPS) analysis provided the phase and composition identification of the sulfur species on hydrated lime and the CaSO₃/CaSO₄ product ratio. Based on the experimental results, the optimum catalyst surface area with a specific particle size is critical to the effective conversion of Ca(OH)₂ into CaSO₃ and CaSO₄. The practicality of a Ca-based desulfurizer and its ability to convert into the required product may be the key to reducing the overall cost of desulfurization in aluminum industry.

在冶炼厂的气体处理中心，氟化氢 (HF) 被从电解槽的出口气体中分离出来，电解槽用于从氧化铝中生产铝。然而，SO2 大部分仍留在废气中。必须开发另一种方法来分离这种对环境有害的气体。在这项研究中，使用熟石灰[Ca(OH)2]作为催化脱硫剂，在特定的湿度条件下，对低浓度二氧化硫气体进行了半干法脱硫。在相对湿度为 17% 的条件下，100 °C 的低反应温度和 Ca 基脱硫剂的最小使用量实现了 95% 以上的二氧化硫去除率。扫描电子显微镜和能量色散 X 射线光谱分析了不同石灰样品的形态变化和硫的存在。布鲁纳-艾美特-泰勒（BET）分析表明，脱硫后熟石灰的表面性质发生了变化。X 射线光电子能谱（XPS）分析提供了熟石灰上硫物种的相位和成分鉴定，以及 CaSO3/CaSO4 产物比。根据实验结果，具有特定粒度的最佳催化剂表面积对 Ca(OH)2 有效转化为 CaSO3 和 CaSO4 至关重要。钙基脱硫剂的实用性及其转化为所需产品的能力可能是降低铝工业脱硫总成本的关键。

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引用次数: 0

Investigation of the influence of crushed sand on carbonation of Mortar: Physical and microstructural analysis 研究碎砂对砂浆碳化的影响：物理和微观结构分析

Cleaner Materials

Pub Date : 2024-11-03 DOI: 10.1016/j.clema.2024.100277

Emmanuel A.M. Elat , Alexandre Pierre , Prosper Pliya , Myriam Duc , Michel Mbessa , Albert Noumowé

The use of crushed sand instead as a substitute for river sand has gained importance in construction practices due to the limited availability of river sand. This study examines the physical and microstructural impacts of crushed sand on mortar carbonation. Using X-ray Diffraction (XRD), Thermo-Gravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM). We highlight the influence of substituting river sand with crushed sand after exposure to 3 % CO₂ in an accelerated carbonation chamber for 28 days. The mass fractions of Ca(OH)₂ and CaCO₃ were determined by thermogravimetric analysis, and a decrease in porosity was observed with an increasing proportion of crushed sand in the mixture. Partial or total substitution of river sand with crushed sand, for environmental purposes, shows improved resistance against CO₂ attack. Our study reveals the beneficial effects of crushed sand in reducing porosity and carbonation compared to river sand.

由于河砂的供应有限，使用碎砂替代河砂在建筑实践中变得越来越重要。本研究探讨了碎砂对砂浆碳化的物理和微观结构影响。研究使用了 X 射线衍射 (XRD)、热重分析 (TGA) 和扫描电子显微镜 (SEM)。我们强调了在加速碳化室中暴露于 3% CO2 28 天后用碎砂代替河砂的影响。通过热重分析测定了 Ca(OH)2 和 CaCO3 的质量分数，并观察到孔隙率随着混合物中碎砂比例的增加而降低。为环保目的，用碎砂部分或全部替代河砂，可提高抗二氧化碳侵蚀的能力。与河沙相比，我们的研究揭示了碎沙在降低孔隙率和碳化方面的有益效果。

引用次数: 0

Biodegradable natural polymers and fibers for 3D printing: A holistic perspective on processing, characterization, and advanced applications 用于 3D 打印的可生物降解天然聚合物和纤维：加工、表征和先进应用的整体视角

Cleaner Materials

Pub Date : 2024-10-30 DOI: 10.1016/j.clema.2024.100275

M.A. Shadab Siddiqui , M.S. Rabbi , Radif Uddin Ahmed , Md. Maruf Billah

The biodegradable natural polymers and fibers could be suggested to revolutionize 3D printing as sustainable, biocompatible, and unique properties in the print matrix for different applications. This review article covers the natural polymers in the form of cellulose, alginate, starch, collagen, silk, chitosan, and gelatin as printing constituents. Furthermore, it includes various natural fibers such as hemp, jute, flax, and bamboo with unique characteristics and advantages in 3D printing. Reinforcements derived from nature have provided better tensile strength, moduli, and flexural properties when infused into polymer matrices, such as PLA, ABS, and PP. Extrusion-based methods, comprising Fused Deposition Modeling (FDM)/Fused Filament Fabrication (FFF), are the most applied techniques of 3D printing for natural-polymer and fiber composites with a principal application in the medical and industrial domains. The future of natural polymers and fibers in 3D printing is becoming very promising despite uniform printability, interfacial adhesion, and mechanical property-related issues. Research in optimizing material composition, processing parameters, and post-processing techniques goes apace to attain the required properties, functionality, and performance. This review provides an outline to researchers and engineers working on 3D printing on the immense potential associated with biodegradable natural polymers and fibers for designing innovative, sustainable, and high-performance products in various applications that contribute to a greener and more sustainable future.

可生物降解的天然聚合物和纤维具有可持续发展、生物相容性和打印基质的独特性能，可用于不同的应用领域，因此可为三维打印带来革命性的变化。这篇综述文章介绍了纤维素、海藻酸盐、淀粉、胶原蛋白、丝绸、壳聚糖和明胶等天然聚合物作为打印成分的形式。此外，文章还介绍了大麻、黄麻、亚麻和竹子等各种天然纤维在 3D 打印中的独特特性和优势。源自大自然的增强材料注入聚乳酸、ABS 和 PP 等聚合物基质后，可提供更好的拉伸强度、模量和挠曲性能。以挤压为基础的方法，包括熔融沉积建模（FDM）/熔融长丝制造（FFF），是天然聚合物和纤维复合材料三维打印中应用最广泛的技术，主要应用于医疗和工业领域。尽管存在均匀打印性、界面粘附性和机械性能相关问题，但天然聚合物和纤维在三维打印中的应用前景非常广阔。为达到所需的特性、功能和性能，优化材料成分、加工参数和后处理技术的研究正在快速进行。本综述向从事三维打印的研究人员和工程师概述了与可生物降解天然聚合物和纤维相关的巨大潜力，以便在各种应用中设计创新、可持续和高性能的产品，从而为更环保、更可持续的未来做出贡献。

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引用次数: 0

Experimental study of phase change material (PCM) biochar composite for net-zero built environment applications 相变材料 (PCM) 生物炭复合材料在净零建筑环境应用中的实验研究

Cleaner Materials

Pub Date : 2024-10-23 DOI: 10.1016/j.clema.2024.100274

Mohamed Katish , Stephen Allen , Adam Squires , Veronica Ferrandiz-Mas

This study presents a novel and sustainable method for integrating octadecane phase change material (PCM) into traditional building materials like mortar and gypsum using vacuum-impregnated biochar. Optimising the impregnation conditions resulted in a PCM-biochar composite with 62.21 % PCM loading and a latent heat energy of approximately 116.7 J.g⁻¹, as measured by Differential Scanning Calorimetry (DSC). Thermogravimetric Analysis (TGA) confirmed the composite’s stability at high temperatures, while accelerated DSC validated its phase change capability and stability over 300 cycles. Characterisation via Scanning Electron Microscopy (SEM), Small-Angle X-ray Scattering (SAXS), X-ray Diffraction (XRD), and Solid-State Proton Nuclear Magnetic Resonance (1H NMR) verifies PCM retention within biochar pores and reveals interactions between PCM and biochar. Additionally, the non-pozzolanic nature of biochar is confirmed. Workability tests show reduced consistency with increased PCM-biochar content in mortar. At 40 % sand replacement rate with PCM-biochar, the compressive strength initially decreases by 45.50 % after 28 days, but it improves to 43 MPa after 120 days. Gypsum samples retain adequate strength for retrofitting applications (2 MPa), demonstrating the potential of PCM-biochar composites to enhance thermal energy storage in building materials, thereby supporting Net-zero building objectives.

本研究提出了一种新颖且可持续的方法，利用真空浸渍生物炭将十八烷相变材料（PCM）融入砂浆和石膏等传统建筑材料中。通过优化浸渍条件，PCM-生物炭复合材料的 PCM 含量达到 62.21%，差示扫描量热仪（DSC）测得的潜热能量约为 116.7 J.g-1。热重分析 (TGA) 证实了该复合材料在高温下的稳定性，而加速 DSC 则验证了其相变能力和超过 300 次循环的稳定性。通过扫描电子显微镜 (SEM)、小角 X 射线散射 (SAXS)、X 射线衍射 (XRD) 和固态质子核磁共振 (1H NMR) 进行的表征验证了 PCM 在生物炭孔隙中的保留情况，并揭示了 PCM 与生物炭之间的相互作用。此外，生物炭的非胶凝性也得到了证实。工作性测试表明，随着砂浆中 PCM 生物炭含量的增加，稠度也会降低。当 PCM 生物炭的砂替代率为 40%时，28 天后的抗压强度最初会降低 45.50%，但 120 天后会提高到 43 兆帕。石膏样品在改造应用中保持了足够的强度（2 兆帕），这表明 PCM 生物炭复合材料具有增强建筑材料热能储存的潜力，从而支持净零建筑目标的实现。

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引用次数: 0

Research trends on thermochromic asphalt mixtures functionalization: Bibliometric analysis and review 热致变色沥青混合物功能化的研究趋势：文献计量分析与综述

Cleaner Materials

Pub Date : 2024-10-10 DOI: 10.1016/j.clema.2024.100273

Larissa Virgínia da Silva Ribas , Iran Gomes Rocha Segundo , Joaquim Carneiro , Elisabete Fraga de Freitas , Verônica Teixeira Franco Castelo Branco

Asphalt mixtures absorb high levels of solar light, increasing their internal temperatures and negatively affecting their behavior. In urban areas, this leads to the urban heat island (UHI) phenomenon, where extensive asphalt coverage raises microclimate temperatures. Integrating thermochromic properties into asphalt could provide a sustainable solution to mitigate UHI while maintaining the necessary mechanical performance. This research reviews the literature, scientific advances, gaps, and future perspectives on thermochromic (TCM) asphalt mixtures through bibliometric analysis and systematic review. The analysis highlights that thermochromic asphalt has recently gained significant scientific interest, with an increasing number of publications from 2013 to 2023. Notably, Hunan University in China has emerged as a leading contributor to thermochromic-related publications. The findings identify the wet method as a prevalent form of thermochromic functionalization, with 4–6% TCM content considered most suitable for thermal performance. Adding TiO₂ improves optical characteristics due to its high reflectance in the Near-infrared solar spectrum. Studies using TCM binders typically show asphalt mixtures with better resistance to rutting and cracking, likely due to enhanced thermoregulation. The key knowledge gaps identified include the lack of consistent procedures across studies, the feasibility of scaling lab-based methods to field applications, and the need for experiments to assess their impact on road safety, surface characteristics, and the durability of thermochromic properties over the pavement’s service life. This review highlights the promise of TCM for urban heat management and emphasizes the importance of additional research to achieve the ideal balance between thermal and mechanical properties.

沥青混合物会吸收大量太阳光，使其内部温度升高，对其行为产生负面影响。在城市地区，这会导致城市热岛（UHI）现象，即大量沥青覆盖会使小气候温度升高。在沥青中加入热致变色特性可为缓解 UHI 提供可持续的解决方案，同时保持必要的机械性能。本研究通过文献计量分析和系统综述，回顾了有关热致变色（TCM）沥青混合料的文献、科学进展、差距和未来展望。分析结果表明，热致变色沥青最近受到了科学界的极大关注，从 2013 年到 2023 年发表的论文数量不断增加。值得注意的是，中国湖南大学已成为热致变色相关出版物的主要贡献者。研究结果表明，湿法是热致变色功能化的普遍形式，4%-6%的中药含量被认为最适合热性能。由于二氧化钛在近红外太阳光谱中的高反射率，添加二氧化钛可改善光学特性。使用中药粘结剂进行的研究通常表明，沥青混合物具有更好的抗车辙和抗开裂性能，这可能是由于热调节性能得到了增强。目前发现的主要知识空白包括：各项研究缺乏一致的程序；将基于实验室的方法推广到现场应用的可行性；以及需要通过实验来评估它们对道路安全、表面特性以及热致变色特性在路面使用寿命内的耐久性的影响。本综述强调了热变色材料在城市热管理方面的前景，并强调了开展更多研究以实现热性能与机械性能之间理想平衡的重要性。

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引用次数: 0

Synergistic impact of geopolymer binder and recycled coarse aggregates on the performance of concrete masonry units 土工聚合物粘结剂和再生粗集料对混凝土砌体性能的协同影响

Cleaner Materials

Pub Date : 2024-10-10 DOI: 10.1016/j.clema.2024.100272

Elen Abuowda, Hilal El-Hassan, Tamer El-Maaddawy

This study examines the combined effect of geopolymeric binder and recycled coarse aggregates (RCA) on the properties of concrete masonry units (CMU). A target 1-day compressive strength of at least 13.8 MPa was attained for all mixes to satisfy the load-bearing strength requirements. Geopolymer mixes made with RCA at replacement rates of up to 100 % were evaluated and compared to a cementitious control mix made with natural coarse aggregates. The environmental and economic impacts were then integrated with the quantity of waste valorized and compressive strength in a multifunctional performance index. Experimental results showed that the utilization of geopolymers as a substitute for Portland cement in the production of CMU did not impact the oven-dry density but reduced the water absorption capacity by up to 26 %. Although the incorporation of RCA negatively impacted these two properties, their values remained within the acceptable range stated by the standards. The geopolymer CMU mix made without RCA had 9 and 25 % lower 28-day compressive and splitting tensile strengths compared to the cement control mix, respectively. Subsequent RCA replacement further reduced these mechanical properties. While the linear drying shrinkage was reduced upon substituting the cementitious binder with the geopolymeric counterpart, RCA replacement of up to 100 % increased the linear drying shrinkage to reach 0.091 %, exceeding the limit set by the standard. Overall, the CMU mix made with geopolymer binder and 75–100 % RCA was found to be optimal for load-bearing applications.

本研究探讨了土工聚合物粘结剂和再生粗集料（RCA）对混凝土砌体单元（CMU）性能的综合影响。所有混合料的 1 天抗压强度目标值至少为 13.8 兆帕，以满足承重强度要求。对使用 RCA（替代率高达 100%）制成的土工聚合物混合料进行了评估，并与使用天然粗集料制成的水泥基对照混合料进行了比较。然后将对环境和经济的影响与废弃物利用率和抗压强度纳入多功能性能指标。实验结果表明，使用土工聚合物替代硅酸盐水泥生产 CMU 不会影响烘干密度，但会降低吸水能力达 26%。虽然掺入 RCA 会对这两项性能产生负面影响，但其值仍在标准规定的可接受范围内。与水泥对照混合料相比，未添加 RCA 的土工聚合物 CMU 混合料的 28 天抗压强度和劈裂拉伸强度分别降低了 9% 和 25%。随后添加的 RCA 进一步降低了这些机械性能。用土工聚合物替代水泥基粘结剂后，线性干燥收缩率降低了，但 RCA 替代率高达 100%，线性干燥收缩率增加到 0.091%，超过了标准规定的限度。总体而言，使用土工聚合物粘结剂和 75% 至 100% 的 RCA 制成的 CMU 混合料最适合用于承重应用。

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引用次数: 0

Valorization of recycled fine powder glass (RFPG) in additive manufacturing: Optimization of the RFPG content in polyethylene terephthalate glycol (PETG) and multi-response analysis 在增材制造中提高回收细粉玻璃 (RFPG) 的价值：聚对苯二甲酸乙二酯（PETG）中 RFPG 含量的优化与多反应分析

Cleaner Materials

Pub Date : 2024-09-30 DOI: 10.1016/j.clema.2024.100271

Markos Petousis , Nikolaos Michailidis , Václav Kulas , Vassilis Papadakis , Mariza Spiridaki , Nikolaos Mountakis , Apostolos Argyros , John Valsamos , Emmanouel Stratakis , Nectarios Vidakis

A cyclic economy and sustainability-driven production are key aspects of the industry. Recycled feedstocks are steadily replacing virgin materials to produce parts and as sustainable additives to develop eco-friendly composites. The reinforcing potential of recycled fine powder glass (FPG) on terephthalate glycol (PETG) is investigated. The performances of six different compounds (with FPG loadings of 2.0, 4.0, 6.0, 8.0, 10.0, and 12.0 wt%) in filament and three-dimensional (3D) specimens form (manufactured with the material extrusion – MEX method) were compared with PETG pure. This research included thermal and rheological analyses, mechanical tests, and morphological and structural investigations. According to these findings, the PETG/RFPG 8.0 wt% composite presented remarkable results in the tensile and flexural (16.3 % and 16.9 % strength increase, respectively) tests, while PETG/RFPG 10.0 wt% had the greatest performance concerning microhardness. Both the dimensional deviation and porosity results show excellent performance in the case of PETG/RFPG 6.0 wt%, by being 67.3 % and 87.1 % improved vs. the PETG pure. These results indicate that RFPG is a promising reinforcement additive for MEX 3D printing that can replace the commonly used inorganic fillers and promote the sustainability of 3D printing.

循环经济和以可持续发展为导向的生产是该行业的关键方面。回收原料正逐步取代原生材料来生产零部件，并作为可持续添加剂来开发生态友好型复合材料。本文研究了回收细粉玻璃（FPG）对对苯二甲酸乙二醇酯（PETG）的增强潜力。将六种不同化合物（FPG 含量分别为 2.0、4.0、6.0、8.0、10.0 和 12.0 wt%）的长丝和三维（3D）试样形式（采用材料挤压 - MEX 方法制造）的性能与纯 PETG 进行了比较。这项研究包括热学和流变学分析、机械测试以及形态和结构调查。研究结果表明，PETG/RFPG 8.0 wt%复合材料在拉伸和弯曲测试中表现出色（强度分别提高了 16.3% 和 16.9%），而 PETG/RFPG 10.0 wt%复合材料在显微硬度方面表现最好。PETG/RFPG 6.0 wt% 的尺寸偏差和孔隙率结果都显示出其优异的性能，与纯 PETG 相比分别提高了 67.3% 和 87.1%。这些结果表明，RFPG 是一种很有前途的 MEX 三维打印增强添加剂，它可以取代常用的无机填料，促进三维打印的可持续发展。

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引用次数: 0

Restaurant food waste valorization by microwave-assisted hydrolysis: Optimization, typological and biochemical analysis 通过微波辅助水解实现餐厅厨余垃圾的价值化：优化、类型学和生化分析

Cleaner Materials

Pub Date : 2024-09-01 DOI: 10.1016/j.clema.2024.100269

Payam Torabi , Nasser Hamdami , Nafiseh Soltanizadeh , Omidvar Farhadian , Alain Le-Bail

Annually, a substantial volume of food waste is being released into the environment. Restaurant food waste (RFW) valorization using microwave-assisted hydrolysis (MAH) is a sustainable approach to produce fermentable sugars. However, RFW is composed of different foodstuffs with different physicochemical, nutritional, and degradation rates. This study explored the typological, chemical, and elemental analysis of RFW. Results revealed that the four main types of RFW were vegetable (33.2 %), meat (19.3 %), rice (15.2 %), and bread waste (11.0 %). The key parameters impacting the MAH of typologically sorted RFW were identified using the Plackett–Burman design (PBD). Then the central composite design (CCD) with 30 runs was used to increase reducing sugar content (RSC). The optimized condition was as follows: temperature 96.0 °C, microwave power 340 W, HCl concentration of 1.45 %, and microwave heating time 11.1 min. The derived hydrolysates were characterized for their biochemical and monosaccharide composition.

每年都有大量食物垃圾被排放到环境中。利用微波辅助水解（MAH）对餐厅厨余（RFW）进行增值是一种生产可发酵糖的可持续方法。然而，餐饮厨余由不同的食品组成，其物理化学、营养和降解率各不相同。本研究探讨了 RFW 的类型、化学和元素分析。结果显示，四种主要的 RFW 类型分别是蔬菜（33.2%）、肉类（19.3%）、大米（15.2%）和面包废料（11.0%）。采用普拉克特-伯曼设计（PBD）确定了影响按类型分类的射频废物 MAH 的关键参数。然后采用中央复合设计（CCD）（30 次运行）来提高还原糖含量（RSC）。优化条件如下：温度 96.0 °C，微波功率 340 W，盐酸浓度 1.45 %，微波加热时间 11.1 分钟。所得水解物的生化成分和单糖成分进行了表征。

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引用次数: 0

An eco-friendly approach to separate emulsified oil from water using all natural materials of chitosan and beach sand 利用壳聚糖和沙滩沙等全天然材料从水中分离乳化油的环保方法

Cleaner Materials

Pub Date : 2024-09-01 DOI: 10.1016/j.clema.2024.100270

Jayaprakash Saththasivam, Oluwaseun Ogunbiyi, Jenny Lawler, Zhaoyang Liu

Oil-contaminated water from oil and gas exploration remains the industry’s primary waste stream. The common method of using chemical coagulation/flocculation followed by air flotation has drawbacks such as generating non-biodegradable and toxic sludge and high operational costs. This study presents an eco-friendly alternative utilizing chitosan and beach sand to remove emulsified oil from water. Chitosan acts as a biodegradable flocculant, while beach sand aids in high-density floc formation and accelerates settling velocity. This approach achieved up to 94 % oil removal efficiency and reduced settling time from 90 to 15 min by using 100 mg/L chitosan and 500 mg/L beach sand with a particle size distribution of 50–100 μm. Shorter settling time reduces capital expenditure compared to conventional methods. Additionally, using natural materials like chitosan and beach sand minimizes toxic sludge generation. This eco-friendly approach offers a promising alternative to conventional methods for treating oily wastewater.

石油和天然气开采过程中产生的受石油污染的水仍然是该行业的主要废物流。先使用化学混凝/絮凝，再使用气浮的常见方法存在产生不可生物降解的有毒污泥和运营成本高昂等缺点。本研究提出了一种利用壳聚糖和沙滩沙去除水中乳化油的环保替代方法。壳聚糖是一种可生物降解的絮凝剂，而沙滩砂则有助于高密度絮凝体的形成并加快沉降速度。通过使用 100 毫克/升壳聚糖和 500 毫克/升粒径分布为 50-100 微米的沙滩沙，该方法的除油效率高达 94%，沉淀时间从 90 分钟缩短到 15 分钟。与传统方法相比，沉淀时间的缩短减少了资本支出。此外，使用壳聚糖和沙滩砂等天然材料可最大限度地减少有毒污泥的产生。这种生态友好型方法为含油废水的传统处理方法提供了一种前景广阔的替代方案。

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引用次数: 0