Waste Glass Research Articles

An Economically Sustainable Glass Recycling Business Model in Puerto Rico: A Conceptual Solution for Regions Without Government Recycling Programs

In Puerto Rico, less than 5% of glass waste is recycled annually compared to a US national average of 25%. In regions like Puerto Rico, where government glass recycling programs are absent, glass presents a challenging waste stream to profitably recycle due to high transportation costs and low market prices, with few scalable models identified in the literature. This study emerged from a multi-year shared action learning partnership between Worcester Polytechnic Institute’s Puerto Rico Project Center and the Corporación del Proyecto ENLACE, a community development NGO serving the Caño Martín Peña communities in San Juan, Puerto Rico. Based on online research and interviews with 16 key stakeholders, we describe an economically sustainable glass recycling business model designed for the Caño Martín Peña communities that offers broader applicability for similar contexts. The business model achieves three goals: (1) it offers a free and convenient glass-collection service for the Caño Martín Peña communities; (2) it generates local employment opportunities in a low-income region; and (3) it operates in an economically sustainable manner. The viability of the glass-recycling business model is premised on strategic partnerships with government agencies, recycling companies, glass-sand markets, and local businesses.

Experimental Study on the Mechanical Properties of Sustainable Concrete using Recycled Plastic and Glass Waste

This study explores using recycled waste glass and plastic fibers as substitutes for fine aggregates in concrete to meet the growing need for sustainable building materials. The basic materials consist of OPC 43 grade and locally obtained river sand. The research incorporates glass powder from crushed beer bottles and plastic fibers from recycled plastic bottles into the concrete mixture. Various tests, including slump, compressive strength (CS), and split tensile strength (STS) assessments, are performed to ascertain the characteristics of the modified concrete in both its fresh and hardened states. The findings demonstrate a significant enhancement in the ease of handling when glass powder is used, exhibiting a surge of 170% and 270% for mixtures, including 15% and 25% glass powder, respectively, compared to conventional OPC concrete. Although including these recycled materials reduces compressive strength (19.95% for SP15 and 21.39% for SP25); tensile strength is significantly improved, with gains of 35% for SP15 and 53.75% for SP25. This research emphasizes the feasibility of integrating waste glass and plastic fibers into concrete as a practical method for sustainable building.

Application of Product of Vitrification of Asbestos-Cement Waste and CRT Glass Cullet as Reinforcing Phase in Surface Composites Produced by FSP Method

In this study, the vitrification of asbestos-cement waste (ACW) and glass cullet from cathode-ray tubes (CRTs) was performed. The resulting product of vitrification from the abovementioned waste was used as the reinforcing phase in a composite with the AA7075 alloy matrix. The composite was made by means of the FSP (friction stir processing) method. The main aim of this work was to determine whether the product of the vitrification can be utilized as the reinforcing phase in the composite. The tests show that introducing the vitrification product into the composite matrix increases both the hardness of the material and its wear resistance. The composite was characterized by a 39% higher hardness and 30.4% higher wear resistance compared to the initial AA7075 alloy. The changes in the properties were caused by strong refinement of the grains, but primarily by the presence of the hard particles of the reinforcing phase in the composite matrix. This research demonstrates that vitrified material, thanks to its properties, can constitute a full-value reinforcing material that can ultimately replace more expensive engineering materials in composites.

Synergistic effects of nano titanium dioxide and waste glass powder on the mechanical and durability properties of concrete

Synergistic effects of nano titanium dioxide and waste glass powder on the mechanical and durability properties of concrete

Investigation of nano-basic oxygen furnace slag and nano-banded iron formation on properties of high-performance geopolymer concrete

Abstract Geopolymers have emerged as promising alternatives to traditional cement-based composites, offering enhanced sustainability and opportunities for recycling industrial waste. The incorporation of waste materials into the binding matrix of geopolymer concrete not only promotes environmental benefits but also significantly improves the overall performance, including mechanical strength, durability, and microstructural integrity of the matrix. This study explores the impact of incorporating varying dosages of nano-basic oxygen furnace slag (NBOFS) and nano-banded iron formation (NBIF) on the properties of high-performance geopolymer concrete (HPGC) that utilizes waste glass as 50% fine aggregate. The research focuses on evaluating both the fresh and mechanical properties, including compressive strength, splitting tensile strength, modulus of elasticity, and flexural strength. Additionally, this study investigated the transport properties of concrete under aggressive environments, such as resistance to chloride penetration, sulfate attack, and sorptivity. The microstructure was examined using scanning electron microscopy. The results demonstrated that the addition of 3% NBOFS and 2.5% NBIF significantly improved the fresh, mechanical, and transport properties of HPGC. These nanomaterials also enhance the splitting tensile strength, flexural strength, and elastic modulus under highly aggressive environmental conditions. The contribution of these nanomaterials to the strength and durability of concrete is particularly relevant in the construction of both substructures and superstructures. Additionally, geopolymer concrete significantly reduces CO2 emissions by eliminating the requirement for ordinary Portland cement and promoting the recycling of waste products, contributing to more environmentally friendly construction practices.

Improving the Rheological Properties of Water-based Drilling Muds Using Waste Glass Powder

Improving the Rheological Properties of Water-based Drilling Muds Using Waste Glass Powder

Synergistic Effects of Waste Glass Powder, High-Frequency Ultrasonic Dispersion, and Liquid Glass Treatment on the Properties of Aluminum-Based Ultra-Lightweight Concrete

This research investigates the impact of waste glass powder, high-frequency ultrasonics (HFUS) dispersion, and liquid glass treatment on aluminum-based ultra-lightweight concrete. Substituting up to 80% of Portland cement with waste glass powder significantly delays hydration and reduces compressive strength by 77%. However, applying HFUS dispersion for 60 s to a mixture with 30% waste glass powder substitution restored compressive strength to the reference value of 3.1 MPa. The combined HFUS and liquid glass treatment enhanced compressive strength by 87%, increased density by 32%, and significantly reduced prosody. Scanning electron microscopy revealed a progressively denser cement matrix with each treatment, highlighting the synergistic effects of these methods in improving concrete properties.

PERFORMANCE CHARACTERISTICS OF A MODIFIED COMPOSITE MATERIAL CONTAINING INORGANIC LIGHTWEIGHT AGGREGATES

A modified thermal and sound insulation composite material, potentially applicable in the field of modern construction, has been developed. Experimental samples based on foam glass aggregate (made from recycled waste glass), perlite (with fraction size up to 3 mm) and hydraulic binders were obtained. The acoustic and mechanical characteristics and the thermal conductivity coefficient of the prepared series of composite samples were studied. Values for Rw in the range from 38 to 46 dB and for λ from 0.04 to 0.15 W m-1 K-1 were established. The influence of the different components of the composition on the values of the studied performance indicators and the structure of the composite was analysed.

Rebar corrosion and bond in concrete with recycled glass granules

Waste glass granules are considered a cost-effective alternative material to replace aggregates in concrete. However, the bond degradation of corroded concrete containing recycled glass granules has not been explored. This study investigated the effect of glass granules on rebar corrosion and the bond loss between rebars and concrete subjected to accelerating corrosion. The compressive strength and pore structure of the concrete were first evaluated, and the corrosion rate and pull-out testing of rebar in concrete were conducted after corrosion. The results show that, despite reducing the initial bond strength before corrosion, a high replacement of recycled glass granules improved the concrete's resistance to corrosion due to the optimized microstructure of concrete. In addition, the compressive strength of the concrete dominated the initial bond strength, which reduced with increasing the corrosion period. However, this negative effect of corrosion was mitigated by increasing the recycled glass granules, followed by reduced bond strength loss and a lower rebar corrosion rate.

Recycling E-waste CRT glass in sustainable geopolymer concrete for radiation shielding applications

Waste cathode ray tube (CRT) glass, enriched with heavy metal of Pb, is classified as hazardous waste and needs to be disposed of harmlessly. This study recycles waste CRT glass as heavy aggregate in sustainable geopolymer concretes (GCs) to enhance its γ-ray shielding performance. It also comprehensively evaluates its macro-performances, microstructure, and environmental and economic impacts. The results demonstrate that the compressive strength of GCs decreases with the dosage of CRT glass. The generation of geopolymer gel is hindered by excessive CRT glass. Besides, the compatibility between CRT glass and the geopolymer matrix is poor. Both factors influence the strength development of CRT glass-incorporated GCs. The compressive strength of GCs with 50 % CRT glass aggregate exceeds 30 MPa, meeting the requirements for building materials. Due to the increase in the density and the introduction of heavy nuclei Pb, the γ-ray shielding performance of GCs is 9 % higher than that of normal concrete. In terms of economic and environmental benefits, this approach realizes the value-added recycling of CRT glass, avoiding the disposal cost of CRT glass. Besides, due to the utilization of sustainable geopolymer as cementitious materials, the carbon footprint of designed CRT glass-enhanced radiation shielding GCs is even 34 % lower than that of normal concrete. This study highlights the advantages of geopolymer and CRT glass in developing sustainable radiation shielding materials for nuclear technology and medicine fields.

Effect of waste glass powder as partial cement replacement on fresh properties, mechanical strength, bond, water penetration and thermal conductivity of normal concrete

Effect of waste glass powder as partial cement replacement on fresh properties, mechanical strength, bond, water penetration and thermal conductivity of normal concrete

Enhancing the mechanical and environmental performance of solidified soil using construction waste and glass micro-powder

The rapid accumulation of construction waste and waste glass, coupled with their environmental hazards, has highlighted the need for sustainable waste management strategies. This study explores the potential of using construction waste (CW) and glass micro-powder (GMP) as innovative additives in soil stabilization, providing both mechanical and environmental benefits. This research focuses on enhancing the compressive strength, tensile strength, and heavy metal stabilization of solidified soils while reducing carbon emissions. Experimental methodologies involved the systematic preparation of soil samples stabilized with various proportions of CW and GMP. Microstructural analyses were conducted using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to understand the formation of cementitious products, including calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H), which play a pivotal role in the strength improvement of stabilized soils. This study found that the optimal formulation of 30 % CW and 15 % GMP improved compressive strength by 56.8 %, from 7.25 MPa to 11.38 MPa, while reducing porosity by 57 % and increasing tensile strength by 85 %. In terms of environmental performance, the combination of CW and GMP enhanced the soil's ability to immobilize heavy metals, with 80 % sequestration efficiency, significantly contributing to soil remediation. These findings underscore the practical engineering significance of utilizing CW and GMP for sustainable soil stabilization, providing a greener alternative to traditional binders and promoting resource efficiency in the construction industry.

Fabrication and characterization of foam ceramics from recycled waste concrete powder and waste glass powder

Incorporating multi-solid wastes to prepare foam ceramics has attracted widespread attention due to its excellent characteristics and environmental protection. In this study, foam ceramics were prepared by sintering method using recycled waste concrete powder (RWCP) and waste glass power (WGP) as the major material, Na2CO3 as foaming agent and borax as fluxing agent. The effect of sintering temperature on the physical properties and pore structure of foam ceramics were studied. The phase transformation and reaction mechanism were also discussed. The results reveal that when the RWCP content was 40%, the WGP content was 60% and the sintering temperature was 890 °C, the foam ceramics showed the best overall performance. The compressive strength, bulk density, water absorption and porosity were 2.39MPa, 0.83g/cm3, 8.27% and 66.68%, respectively. At this time, the pore size distribution was optimal, and mesopore occupied the vast majority. The fractal dimension of pore reached the minimum of 1.09. In addition, The XRD results showed that WGP and RWCP gradually depolymerized and reconstructed under the action of flux. Then the foam ceramics with mullite, pyroxene and wollastonite as the main phases were formed. The experimental results showed that it was feasible to prepare foam ceramics using RWCP. This study can provide a new train of thought for the reuse of RWCP.

Automated repair of asphalt pavement cracks and potholes utilizing 3D printing and LiDAR scanning

This study introduces a method for automatic repair of asphalt pavement cracks and potholes using 3D printing and LiDAR scanning. A scanning method was developed to accurately detect and represent cracks and potholes in a 3D model. To address the limitations of LiDAR scanning, such as missing data points caused by the irregular shapes of cracks and potholes, the screened Poisson method was applied to reconstruct the missing data points. These models were validated through both theoretical calculations and sand test. In addition, the research focuses on optimizing key 3D printing parameters, such as printing temperature and printing speed, to enhance performance of crack repair throughout semi-circular bending test. Direct tensile strength test was employed to assess the impact of waste materials (e.g., rubber tire powder and waste glass) on the bond strength of filled sample. The results indicated a volume difference of 2–5 % between the scanning method and the sand test method, demonstrating high accuracy in detecting and reconstructing 3D cracks/potholes. Binders modified with 10 % rubber tire powder, or 20 % waste glass exhibited the highest tensile strength of 212 kPa and 207 kPa, respectively. However, using more than 30 % waste materials is not recommended due to a significant reduction in bond strength compared to conventional binders. An optimal 3D printing speed of 180 mm/min and a temperature of 117 °C are recommended for use in 3D printing in laboratory conditions. It was also noted that higher printing speeds decrease indirect tensile strength, highlighting the importance of balanced parameter settings.

Alkaline activation via in-situ caustification of one-part binders of composite precursors of waste glass and limestone

Mixtures of powders of waste glass (WG), limestone (LS), Na2CO3 and CaO were used to formulate novel one-part in situ alkali-activated cement (WG-AAC). The in-situ interaction Na2CO3-CaO-H2O promoted the formation of CaCO3 and NaOH, which promoted the WG and LS dissolution and influenced the micro- and molecular features of the resulting cementitious products. Pastes and mortars developed 1-year strengths of up to 29 MPa and were stable underwater. Characterization by XRD, SEM, EDS, and 29Si-NMR indicated that a Na2CO3:CaO ratio close to 1:1 resulted in polymerized C-S-H, CaCO3, silica gel, and Ca-modified silica gel, which were intimately intermixed and possibly crosslinked through Q3 bonds. Such phases interacted synergistically improving the underwater stability of the WG-AAC, indicating that in-situ caustification is a suitable and practical alkaline activation for SiO2-rich precursors.

Lightweight aggregates produced from low-temperature sintering of multiple solid wastes for heavy metals removal: Adsorption kinetics and stabilization

Solid wastes, including incinerated sewage sludge ash (ISSA), waste bentonite, and waste glass powder (WGP), were recycled and sintered at a low temperature (680°C) to produce lightweight aggregates (WSA). WGP acted as a fluxing agent to significantly lower sintering temperature of 1000-1200°C in other studies. WSA demonstrated an excellent mechanical strength of 3.76 MPa. The adsorbent dosage, initial pH, kinetics and isotherm on heavy metals adsorption were evaluated in batch adsorption experiments. The isothermal data exhibited a good correlation with the Langmuir model, and the maximum adsorption capacity was approximately 9.26 mg/g at 296 K. Pb(II) removal was dominated by precipitation and cation exchange. Breakthrough curves were determined for fixed-bed adsorption. At 50% breakthrough, the maximum adsorption capacity was 1.82 mg/g. The WSA after heavy metals adsorption were then reused to replace river sand (10-50%) in producing lightweight mortars. The solidification of spent WSA in the lightweight mortars could significantly reduce the leaching of Pb(II) by 98.5%. Moreover, the reuse of spent WSA resulted in low density and low thermal conductivity of cement mortars. This study demonstrates total waste management for municipal solid wastes: upcycling of waste–utilization–permanently stored as construction materials.

Optimization of the thermal and mechanical properties of concrete with steel slag coarse aggregates and waste glass replaced with cement

Optimization of the thermal and mechanical properties of concrete with steel slag coarse aggregates and waste glass replaced with cement

Functionalizing heavy metal contained incinerated sewage sludge ash in recycled glass-based alkali-activated materials for sewer environment

This study evaluates the performance of alkali-activated cement (AAC) mortars in an artificial sewage environment. The mortars, initially prepared with waste glass powder (GP) and ground granulated blast furnace slag (GGBS) in a 50:50 mass ratio, were modified by replacing 10 wt% of GGBS with incinerated sewage sludge ash (ISSA) with the goal of offering a biocidal effect. Comparisons were made with calcium aluminate cement (CAC), metakaolin (MK), and MK combined with zinc ferrite nanoparticles, each at a similar GGBS replacement level. The results showed that only incorporating CAC improved the strength development, achieving compressive and flexural strengths of 62.7 MPa and 7.4 MPa, respectively, at 28 days, while introducing ISSA or MK reduced the compressive strength to 47 MPa and flexural strength to 4.5 MPa. Although heavy metal ions from ISSA or zinc ferrite nanoparticles minimized biofilm thickness, they could not compensate for the reduced strength and increased alkalis leaching. Among all the tested mixtures, the 50GP40GGBS10CAC mixture exhibited superior biogenic acid resistance, possibly due to its Al-rich C-N-A-S-H gel phases (Ca/Si = 0.4, Na/Al = 0.8, Si/Al = 3.4) and refined pore structure (porosity = 3.4 %), making it the most microbial acid-resistant option for sewer rehabilitation.

Optimizing mix design methods for using slag, ceramic, and glass waste powders in eco-friendly geopolymer mortars

Optimizing mix design methods for using slag, ceramic, and glass waste powders in eco-friendly geopolymer mortars

Recycling and optimum utilization of CRT glass as building materials: An application of low CO2 based circular economy for sustainable construction

The construction industry is the major contributor of CO2 emission around the globe. The rapid advances in the electronics industry have transformed the disposal of cathode ray tube glass waste (CRT-WG) into a prominent environmental concern. Recycling of CRT glasses as building materials can help in the production of sustainable construction. Numerous previous studies have documented that CRT-WG can be utilized either as a component of fine aggregate or binder material as it provides a cleaner solution and reduce carbon emission. Under this cleaner production and low CO2 emission perspective, this paper provides a thorough review of the previous studies on the utilization of CRT glass as a partially and fully substitute of sand and cementitious material in mortar production and propose an application of CO2 based circular economy model for reduce carbon emissions. This paper summarized the fresh, mechanical and durability properties of mortar incorporating treated and un-treated CRT-WG with different mineral additives and w/b ratios. Furthermore, this research explores the optimal proportions of CRT glass that can be use as replacements for sand and cement powder to make eco-friendly and sustainable low carbon mortar suitable for both structural and non-structural applications. More particularly, this review emphasizes the benefits, the need for additional research, and the drawbacks of CRT-WG use in construction building. Overall, this study proposes that incorporating CRT glass into building materials through a low CO2 based circular economy offers significant potential advantages. This study will help in optimization of CRT glass in concrete mix design in combination with waste materials for sustainable construction.