Conversion Of Waste Materials Research Articles

GENERATION OF ELECTRICITY FROM WASTE PAPERS AND PLASTIC

A waste-to-energy plant effectively addresses the dual challenges of waste management and energy production by converting waste materials, such as plastics and paper, into electricity. This project particularly targets the issue of waste management in Nigerian cities, where waste plastics pose significant environmental and health risks. Through the incineration of these materials, not only is waste volume drastically reduced by approximately 80-95%, but the process also generates a considerable amount of electricity. Employing a “Zaar box” for combustion, the heat generated converts water into steam, driving a turbine to produce electricity. This electricity is then stored in batteries for various uses, such as lighting bulbs, showcasing a live demonstration of energy production from waste. The study supports its viability with a detailed analysis of the energy potential of waste plastics, suggesting significant contributions to Nigeria’s energy supply and offering a sustainable solution to both waste surplus and power shortages The waste-to-energy project in Raj Shahi City utilizes everyday waste materials, such as plastics and paper, to generate electricity. The city produces approximately 3083 kg of waste daily, which is incinerated to produce around 12 MW of power, effectively reducing the frequency of load shedding in the area. This method not only provides a reliable source of energy but also significantly diminishes the volume of waste, reducing the need for landfill space by 80-95%. Keywords: 1)Waste materials, 2)Generate Electricity, 3)Heating penal, 3)Zaar box, 4)Bulb glowing.

Electrical Power Generation from Waste Products

Electricity generation by burning waste materials, also known as thermal waste-to-energy, is a process that involves converting waste materials into electricity by burning them in a combustion chamber. This process is a sustainable solution for waste management as it reduces the volume of waste sent to landfills while producing renewable energy. The methodology for electricity generation by burning waste materials typically involves waste collection, handling, and preparation, incineration, energy recovery, and ash management. The generated electricity can be used for local communities or industries or fed back into the national grid. The process of electricity generation by burning waste materials provides a reliable source of electricity while reducing greenhouse gas emissions by avoiding the release of methane gas from landfills. Overall, electricity generation by burning waste materials is a promising solution for waste management and renewable energy production. However, it is important to carefully consider the potential benefits and drawbacks of this method and to ensure that appropriate regulations and technologies are in place to minimize any negative environmental impacts. Key Word: Heating panels, Led Bulbs, zaar box, IN4007, Battery 4.5V, Resistors, and capacitors

Characterization and optimization of waste-derived biodiesel utilizing CNT/MgO nanocomposite and water emulsion for enhanced performance and emission metrics

Efficiently managing agricultural plant residues is a growing concern, leading to a focus on converting waste materials into valuable resources. The Rutaceae family, especially Citrus maxima peel oil (CMPO), has potential for biofuel production, but research on its use remains limited, especially in terms of fuel modification. This study aims to extract biofuel from Citrus maxima peel and characterize its chemical components. To enhance efficiency and align with environmental goals, the study suggests integrating water and a nanocomposite into CMPO. An eco-friendly method was employed to synthesize a carbon nanotube (CNT)-induced magnesium oxide (MgO) nanocomposite that was extensively characterized. Fuel combinations were derived using a Box-Behnken design matrix, and optimization followed, emphasizing performance and emission parameters. Analysis of the elemental composition and free fatty acid profile of extracted CMPO highlights its potential as an alternative fuel. Optimal concentrations of CMPO, water, and nanocomposite in diesel fuel were found to be 27.6%, 12.2%, and 64.9 ppm, respectively. Confirmation tests validated improved performance and emission outcomes under these optimal conditions. Projected performance and emission parameters closely align with experimental findings. The proposed fuel combination is expected to achieve a significant 40% reduction in the demand for petroleum derivatives.

Removal of Copper(Cu) from Wastewater Using Modified Recycle Carbon Black (RCB) Waste Tyre

In this century, sustainability has become an essential element in any project to ensure a safe environment. The conversion of waste materials is an important step towards achieving sustainability. Moreover, converting these materials into adsorbents to treat wastewater shows great potential, especially due to its cost-effectiveness and the reduction of solid waste disposal. This research study aims to investigate the removal of Copper (Cu) from wastewater using waste tyre-recycled carbon black (WT-rCB) and modified waste tyre-recycled carbon black (WT-dAC) to determine their adsorption capability. The removal of Copper using WT-rCB and WT-dAC were investigated with various parameters: pH value, adsorbent dosage, and contact time. The chemical-physical activation process was employed to produce the WT-dAC. First, WT-rCB was impregnated with 1:5 wt% of 1 M KOH solution, then physically activated at 650 °C for 1 hr with flowing Nitrogen gas at 1 L/min. The adsorption study observed a removal efficiency of up to 65% using WT-dAC, while WT-rCB showed a removal efficiency of 22% under the optimum conditions. Eventually, the study demonstrates the employability of WT-dAC in the removal of Copper (Cu) from wastewater.

The Effects of Fungal Fermented Feeds on Broiler Chicken Growth Performance, Gut Morphology, and Gastrointestinal Tract Microecology: A Review

Due to the shortage of poultry feed ingredients and the resultant continuous increase in their prices, researchers have been looking for their alternatives. Agricultural wastes and by-products (such as wheat bran, rice husk, sour cherry kernel, palm kernel, cassava pulp, rapeseed meal, and corn meal) are among such alternatives, although they cannot be used directly due to their high crude fiber content. Fermentation is an evolving process that converts complex substrates into simpler molecules using bacteria, fungi, and other microorganisms. It improves the nutrient content of feed ingredients. It is also used to ferment agricultural waste materials in order to improve their nutritional value, so they can be utilized as broiler feed. Moreover, it can provide an inexpensive feed source to poultry industry and convert waste materials into a useable product. Different bacterial and fungal strains are employed for fermentation. This review focuses on the use of fungal fermented agricultural waste-based feed and its effects on broiler chicken growth performance, gut morphology, and gastrointestinal tract microecology.

Experimental and numerical analysis of concrete slabs reinforced with rebar and recycled steel fibers from waste car tyres

In light of various initiatives taken around the world to convert waste materials into new products, the objective of this paper is to promote the use of steel fibers from recycled car tyres in the concrete industry. Hybrid steel fiber reinforced concrete (HSFRC) is a material that combines two or more types of steel fibers, in this case: manufactured steel fibers and recycled steel fibers from waste car tyres in equal proportions. The main objective of the presented research was to investigate the possible application of HSFRC in structural elements with conventional reinforcing bars in order to improve the flexural behavior and to investigate the possibility of partially replacing the conventional reinforcement with steel fibers in terms of service performance. For this purpose, eight slab specimens with different reinforcement ratios were subjected to a four-point bending test to measure displacements, strength, and crack widths. The addition of a hybrid fiber mix to a conventionally reinforced concrete slab significantly reduced crack widths by up to 53%. The addition of fibers compensated for a conventional reinforcement reduction of 20% by reducing crack widths by up to 38%. It was observed that slightly more cracks opened with smaller widths and at smaller distances from each other in these slab types than in the conventionally reinforced reference slabs. Slabs with hybrid fiber mix and 44% reinforcement reduction showed no improvement in crack control compared to the conventionally reinforced concrete reference slabs. Using numerical models in ABAQUS simulating the flexural test on notched prismatic specimens, a calibration of the material models of plain concrete, and HSFRC was performed based on the test results. These validated material models were used for numerical modeling of slabs. The results of the analyses compared with the experimental results showed good agreement and confirmed the ability of the proposed material model of HSFRC to predict the flexural behavior of slabs with conventional reinforcement.

Gasification of Solid Recovered Fuels with Variable Fractions of Polymeric Materials

Gasification is a promising thermochemical technology used to convert waste materials into energy with the introduction of low amounts of an oxidant agent, therefore producing an environmental impact that is lower when compared to incineration and landfilling. Moreover, gasification allows a sustainable management of wastes and reduces the use of fossil fuels responsible for the increment of greenhouse gases. This work aimed to perform gasification tests with solid recovered fuels (SRF) containing organic fractions mainly retrieved from construction and demolition wastes to assess the potential for energy conversion. Tests were conducted in a pilot-scale downdraft gasifier (maximum feedstock input of 22 kg/h) at c.a. 800 °C, using SRF samples containing different proportions of polymeric wastes ranging between 0 and 20 wt %. Gas and chars obtained as by-products were analysed to evaluate their properties and to establish valid pathways for their valorisation. The addition of polymeric wastes reduced char production but rose both tar and HCl concentrations in the gas. The SRF with 10 wt % of polymeric wastes generated the best results, producing the highest calorific value for the gas (3.5 MJ/Nm3) and the highest cold-gas efficiency (45%). Possible char applications include their use as catalysts for tar decomposition, or as an additive in construction materials. Gasification can therefore be considered a valid solution for the energetic valorisation of these SRFs.

The valorisation of grass waste for the green synthesis of graphene quantum dots for nonlinear optical applications

The recent years have seen an increase in efforts to develop a simple and less complex method of converting waste materials into graphene nanomaterials. Herein, we present the valorisation of grass waste for the green synthesis of graphene quantum dots (GQDs) using hydrothermal technique. The efficacy of using three different precursors that had been sourced from green waste materials to produce GQDs was investigated; namely, grass waste, and grass waste-derived cellulose, and cellulose nanocrystals. The resulting GQDs were characterised using UV–Vis spectroscopy, fluorescence spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The UV–Vis analysis revealed the existence of π-π* transition of the CC bond of the GQDs samples while the FTIR results showed the samples contained typical functional groups; such as O–H, CO, and C–O. The surface functionalisation of the GQDs was further corroborated by the XPS analysis. The Raman analysis indicated that the structure of the GQDs was highly functionalised, with a more prominent D-band than G-band indicating a high ID/IG ratio. The morphological analyses, which were conducted using TEM and AFM, showed that the particles of the samples were uniform in size and circular in shape. The AFM analysis found that the thickness of the GQDs samples ranged between 0.5 and 2.6 nm, implying that the samples contained 1–3 layers of GQDs. Further analysis using the Z-scan technique indicated that the GQDs exhibited strong nonlinear refraction and nonlinear absorption which holds great promise for nonlinear integrated applications such as optical limiting, optical switching, image transmission, logic devices and mode-locked laser system, and so on.

Conversion of Plastic Waste to Carbon-Based Compounds and Application in Energy Storage Devices.

At present, plastic waste accumulation has been observed as one of the most alarming environmental challenges, affecting all forms of life, economy, and natural ecosystems, worldwide. The overproduction of plastic materials is mainly due to human population explosion as well as extraordinary proliferation in the global economy accompanied by global productivity. Under this threat, the development of benign and green alternative solutions instead of traditional disposal methods such as conversion of plastic waste materials into cherished carbonaceous nanomaterials such as carbon nanotubes (CNTs), carbon quantum dots (CQDs), graphene, activated carbon, and porous carbon is of utmost importance. This critical review thoroughly summarizes the different types of daily used plastics, their types, properties, ways of accumulation and their effect on the environment and human health, treatment of waste materials, conversion of waste materials into carbon-based compounds through different synthetic schemes, and their utilization in energy storage devices particularly in supercapacitors, as well as future perspectives. The main purpose of this review is to help the targeted audience to design their futuristic study in this desired field by providing information about the work done in the past few years.

Converting solid waste materials to Energy: A review

This minireview characterizes waste materials and their composition in African cities using existent literature, highlights methods that can be used to convert waste materials to energy and examines the progress and prospects of use of wastes to enhance energy security in the regions. It was found that African cities produce about 125 million tons of municipal waste materials with a maximum per capita generation rate of 0.8 kg daily. Decomposable organic materials form majority of the waste constituents (40–80%) in major African cities. The evaluated approaches to convert waste to energy are based on thermal and biochemical conversions to produce energy rich substrates and gases that can be used as heat and power production feedstocks. It was also established that most African cities are yet to embrace waste-to-energy (WTE) initiatives of recycling due to financial, legislative and technical constrains despite flaring most of their municipal wastes and having adequate climatic conditions for production of landfill gas. To overcome the challenge, this research recommended for more commitment by governing and regulatory authorities of African cities to fund renewable energy initiatives such as WTE and the enactment of appropriate policies to implement such initiatives and optimize their potential to enhance energy security in the continent.

Utilization prospects of eggshell powder in sustainable construction material – A review

With the rapid growth of infrastructure development, the demand for construction materials has also increased. Cement is one of the materials used widely around the world. Using nonrenewable resources in the production of cement and the CO2 emissions has created significant environmental issues. Using waste materials as a partial or full replacement for cement is one of the practical solutions available. The conversion of waste materials into a cement replacement may reduce the environmental issues caused by the open dumping of the waste. Eggshell is a waste material that can be obtained from restaurants, bakeries and households. If effective uses for eggshell can be found, it would create an opportunity for a sustainable solution. This paper presents the latest studies on the use of eggshell powder in construction materials such as concrete, cement mortar, brick, alkali-activated binder and a soil stabilizer. The physical and chemical properties of the eggshell powder and the factors that influence the characteristics of eggshell power were also analyzed. The results indicate that the characteristics of cementitious materials improved. Specifically, a 10–15% cement replacement with eggshell powder results in strength development comparable to the control. Several studies have shown the potential of using eggshell powder as a stabilizer for soil and brick to improve its mechanical properties. Eggshell powder is therefore energy and cost-effective solution to the problem of sustainable construction materials.

A 37-amino acid loop in the Yarrowia lipolytica hexokinase impacts its activity and affinity and modulates gene expression

The oleaginous yeast Yarrowia lipolytica is a potent cell factory as it is able to use a wide variety of carbon sources to convert waste materials into value-added products. Nonetheless, there are still gaps in our understanding of its central carbon metabolism. Here we present an in-depth study of Y. lipolytica hexokinase (YlHxk1), a structurally unique protein. The greatest peculiarity of YlHxk1 is a 37-amino acid loop region, a structure not found in any other known hexokinases. By combining bioinformatic and experimental methods we showed that the loop in YlHxk1 is essential for activity of this protein and through that on growth of Y. lipolytica on glucose and fructose. We further proved that the loop in YlHxk1 hinders binding with trehalose 6-phosphate (T6P), a glycolysis inhibitor, as hexokinase with partial deletion of this region is 4.7-fold less sensitive to this molecule. We also found that YlHxk1 devoid of the loop causes strong repressive effect on lipase-encoding genes LIP2 and LIP8 and that the hexokinase overexpression in Y. lipolytica changes glycerol over glucose preference when cultivated in media containing both substrates.

Abatement of hazardous materials and biomass waste via pyrolysis and co-pyrolysis for environmental sustainability and circular economy.

The remarkable journey of progression of mankind has created various impacts in the form of polluted environment, amassed heavy metals and depleting resources. This alarming situation demands sustainable energy resources and approaches to deal with these environmental hazards and power deficit. Pyrolysis and co-pyrolysis address both energy and environmental issues caused by civilization and industrialization. The processes use hazardous waste materials including waste tires, plastic and medical waste, and biomass waste such as livestock waste and agricultural waste as feedstock to produce gas, char and pyrolysis oil for energy production. Usage of hazardous materials as pyrolysis and co-pyrolysis feedstock reduces disposal of harmful substances into environment, reducing occurrence of soil and water pollution, and substituting the non-renewable feedstock, fossil fuels. As compared to combustion, pyrolysis and co-pyrolysis have less emission of air pollutants and act as alternative options to landfill disposal and incineration for hazardous materials and biomass waste. Hence, stabilizing heavy metals and solving the energy and waste management problems. This review discusses the pyrolysis and co-pyrolysis of biomass and harmful wastes to strive towards circular economy and eco-friendly, cleaner energy with minimum waste disposal, reducing negative impact on the planet and creating future possibilities.

Conversion of Waste Materials into Heterogeneous Oxidation Catalysts for Treatment of Chlorinated Organics

AbstractWaste disposal is a challenging environmental concern worldwide. Carbon-rich waste materials can be transformed into adsorbent and/or catalyst support to reduce treatment costs and promote ...

Nanotechnology Approaches for Improving the Healthiness and Sustainability of the Modern Food Supply.

Nanotechnology has been successfully used in many commercial applications to create innovative products with new or improved functional attributes. In this article, the utilization of nanotechnology to improve the healthiness and sustainability of the modern food supply is demonstrated with various examples. The food industry has been highly successful in producing a diverse range of safe, affordable, tasty, and convenient foods, but many of these foods and their production methods are having damaging effects on the health of people and the environment. Nanotechnology is helping to create a new generation of foods with lower calorie densities, slower digestibility, and higher satiety, as well as to fortify foods with vitamins, minerals, and nutraceuticals in a bioavailable form. It is also being used to create nanopesticides and nanofertilizers to improve yields and reduce waste associated with agricultural production. Moreover, nanotechnology is being used to create tiny sensors that provide information about food quality and safety. Finally, it is being used to convert waste materials into valuable commodities, such as plant-based packaging materials to replace plastics.

Fe3O4 nano assembly embedded in 2D-crumpled porous carbon sheets for high energy density supercapacitor

• The waste garlic husk can act as a carbon (2D-CCS) precursor as well as a solvent . • A novel 0D-Fe 3 O 4 nano assembly and 2D-CCS composite was synthesized with zero-waste generation. • The composite shows outstanding power and energy densities (8000 W kg −1 , 115.5 Wh Kg −1 ) of a supercapacitor. • The 2D crumpled nano-sheet assembly affords high specific capacitance in a supercapacitor application. • This work stimulates a new and universal door converting waste materials to valuable materials. Due to the copious development of industries and depletion of fossil fuels generate deteriorating environmental pollution and appalling economic crisis. Thus, there are increasing unmet for developing well-defined nanostructures to mitigate energy and environmental issues. Herein, we firstly report a unique concerted method to convert agro bio-waste into an economical wealth material. By the inspiration of nature, we selected a waste 2D garlic husk ( Allium sativum ) as a torchbearer to make a unique material. The garlic extract was applied for the synthesis of Fe 3 O 4 NAs@2D-CCS composite nano-assemblies (NAs). Interestingly, the small-sized Fe 3 O 4 nanocrystals (<20 nm) underwent nucleation in the presence of biogenic 2D-CCS and formed a pomegranate like a cluster (200 nm) forming a conglomerate on porous carbon layers. Most importantly, no secondary waste was generated in this work. This Fe 3 O 4 NAs@2D-CCS composite affords high specific capacitance of 820F g −1 at a current density of 0.5 A g −1 , which is nearly 5 to 3 times higher than pristine Fe 3 O 4 NPs (<20 nm) electrode with an outstanding power density (3500–8000 W kg −1 ) and specific energy density (115.5 to 65.9 Wh Kg −1 ), which is superior among most of all reported iron oxide and graphitic carbon composites. This simple work stimulates a new door for the generation of waste to well-defined nanostructure materials for energy, catalysis, and environmental applications.

Adsorption of As(V) and Ni(II) by Fe-Biochar composite fabricated by co-pyrolysis of orange peel and red mud

This study aimed to compare the adsorption performance of Fe-biochar composites (Fe–C–N2 and Fe–C–CO2), fabricated by co-pyrolysis of red mud and orange peel in N2 and CO2, for As(V) and Ni(II). By the syngas production comparison test, it was confirmed that CO2 was more advantageous than N2 as a pyrolytic medium gas to produce more CO. The resulting Fe-biochar composite showed the aggregate morphology consisting of different Fe phases (magnetite or metal Fe) from the inherent hematite phase in red mud and carbonized carbon matrix, and there was no distinct difference between the structural shapes of two Fe-biochar composites. Adsorption experiments showed that the adsorption capacities for As(V) and Ni(II) in single mode were almost similar with 7.5 and 16.2 mg g−1 for Fe–C–N2 and 5.6 and 15.1 mg g−1 for Fe–C–CO2, respectively. The adsorption ability of Fe–C–CO2 for both As(V) and Ni(II) was further enhanced in binary adsorption mode (As(V): 13.4 mg g−1, Ni(II):17.6 mg g−1) through additional removal of those ions by Ni(II)–As(V) complexation. The overall results demonstrated CO2-assisted pyrolysis can provide a viable platform to convert waste materials into fuel gases and environmental media for co-adsorption of cationic and anionic heavy metals.

Simulation of Low Density Polyethylene (LDPE) Pyrolysis and Optimisation of Pyro-Oil Yield

Abstract Plastic pyrolysis has been studied over the years and has been proven to be a viable method of converting waste materials into useful products. Low-density polyethylene (LDPE) is of particular interest as it makes up a significant part of solid waste stream. Aspen HYSYS was used to model the steady-state pyrolysis of waste low-density polyethylene (LDPE) based on a combination of kinetic and thermodynamic approaches. The results of the numerical optimisation (at a basis of 10 kg/h feed) showed that 100% conversion and a maximum of 91.6% oil yield can be achieved at a temperature of 449 °C and a purge gas flowrate of 1.21 kg/h. Reaction temperature was found to be a more important process factor than purge gas flowrate. Correlations were also developed for the prediction of oil yield and reaction conversion based on the process temperature and purge gas flowrate. The analysis of variance (ANOVA) showed that the correlations for both reaction conversion and oil yield were statistically significant.

Composite Properties of Non-Cement Blended Fiber Composites without Alkali Activator.

The vigorous promotion of reuse and recycling activities in Taiwan has solved a number of problems associated with the treatment of industrial waste. Considerable advances have been made in the conversion of waste materials into usable resources, thereby reducing the space required for waste storage and helping to conserve natural resources. This study examined the use of non-alkali activators to create bonded materials. Our aims were to evaluate the feasibility of using ground-granulated blast-furnace slag (S) and circulating fluidized bed co-fired fly ash (F) as non-cement binding materials and determine the optimal mix proportions (including embedded fibers) with the aim of achieving high dimensional stability and good mechanical properties. Under a fixed water/binder ratio of 0.55, we combined S and F to replace 100% of the cement at S:F ratios of 4:6, 5:5, 6:4. Polypropylene fibers (L/d = 375) were also included in the mix at 0.1%, 0.2% and 0.5% of the volume of all bonded materials. Samples were characterized in terms of flowability, compressive strength, tensile strength, water absorption, shrinkage, x-ray diffraction (XRD) and scanning electron microscope (SEM) analysis. Specimens made with an S:F ratio of 6:4 achieved compressive strength of roughly 30 MPa (at 28 days), which is the 80% the strength of conventional cement-based materials (control specimens). The inclusion of 0.2% fibers in the mix further increased compressive strength to 35 MPa and enhanced composite properties.

Azo dye adsorption on an industrial waste-transformed hydroxyapatite adsorbent: Kinetics, isotherms, mechanism and regeneration studies

Nanocrystalline hydroxyapatite (HAp) with high surface area was synthesized by surfactant-assistant hydrothermal method from an industrial waste phosphogypsum. X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen sorption characterizations revealed that HAp crystals grow as needle-like particles along the c direction with surface area of 86 and 135 m2/g for the samples synthesized without and with Brij-93 surfactant, respectively. Adsorption of anionic azo dye Congo Red (CR) were conducted on both samples, taking into account the influence of initial dye concentration (100–500 mg/L), adsorbent dosage (0.5–30 g/L), contact time (5–180 min) and solution pH (2–12). Kinetic studies showed that the adsorption of CR followed pseudo-second-order model, i.e., chemisorption is the rate controlling step. Freundlich isotherm was found to be most suitable model for the adsorption of CR, i.e. adsorption is multilayer process. The calculated maximum adsorption capacity of synthesized B93-HAp adsorbent using Brij-93 surfactant was found to be 139 mg/g at pH 5.5 and dosage of 2 g/L. Two predominant mechanisms were observed for CR adsorption, electrostatic attraction and hydrogen bonding as revealed by Fourier transformed infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) studies. The multi-cycle sorption/desorption tests indicated that waste-transformed adsorbent could be regenerated and reused up to 6 cycles. Therefore, this work shows that the conversion of waste materials into adsorbents has a two-fold environmental benefit for both waste management and wastewater treatment.