Waste Materials In Order Research Articles

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.

Production of fuels by pyrolysis of waste plastics: technical notes

This paper described the plant scale catalytic process of the plastic waste materials in order to obtain an alternative fuel from three plastic wastes Polypropylene (PP), Polystyrene (PS) and Polyethylene (PE). Pyrolysis is the thermochemical decomposition of plastics at elevated temperatures (in absence or little supply of oxygen) into a range of useful products: gas, liquid, and solid residue. These waste have plastics consisting of PP, PE and PS, are first sorted manually and crushed by using crusher and finally feed in the reactor enclosed in the burner maintaining the reaction temperature about 500°C. Nitrogen gas is used to create inert environment and for fluidization in reactor. The produced cracked gas is now sent to be condensed to a condenser followed by the series of cyclone separator and electrostatic precipitator then finally feed into the liquid vapor separator. The plastic pyrolysis plant is design of capacity 3.2 tons of plastics each day, obtained 80% gaseous fuel and 7% Liquid and remaining as residue. The variation of yield of the products according to increase in temperature is also shown in this paper.

Experimental study on Partial Replacement of Cement by Granite Powder

The usage of cement has expanded significantly as a result of daily advancements and development in the construction industry, and the amount of solid debris generated during construction demolition has also increased significantly. These factors led to the reuse of destroyed construction waste like granite powder, which helped to minimize both the amount of solid waste produced and the shortage of cement needed to make concrete. Waste generated from the manufacturing facility of granite powder also results from the destruction of buildings. According to studies, 20–30% of the material prepared in powder production plants ends up as waste. Due to the limited supply of cement, it should be necessary to make use of this waste material in order to manage building wastes. In place of cement, crushed waste granite powders are used. 0%, 30%, 35%, 40%, and 45% of the cement was substituted with crushed granite waste powder. Concrete of the M25 grade has been developed and tested. By substituting different percentages of crushed powder for cement, several mix designs for various sorts of mixes were created. Following completion of the 7, 14, and 28-day curing periods, experimental studies were conducted to determine the workability, compressive strength, split tensile strength, and flexural strength of various concrete mixes containing various percentages of crushed trash. It has been found that as the percentage of crushed powder replacement increases, so does the workability. Additionally, the fine granite powder boosts concrete strength by up to 35% percentage.

Development of green and sustainable ultra-high-performance concrete composite reinforced with date palm fibers

In a sustainable approach, it is essential to reduce the volume of agricultural waste materials in order to minimize environmental and health concerns. To pursue this goal, agricultural wastes, mainly date palm fibers (DPFs), was used as a partial replacement of conventional steel fibers to produce ultra-high-performance concrete (UHPC). The UHPC has been used to describe a steel-fibers-reinforced cementitious composite with a very low water-binder ratio. It is one of the most significant breakthroughs in concrete technology in the 20th century due to its outstanding mechanical performance, such as compressive strength over 150 MPa and flexural strength over 30 MPa. The cost of UHPC is known to be significantly higher compared to ordinary reinforced concrete because it requires large quantities of steel fibers. This paper aims to study the feasibility of utilizing DPFs as a partial replacement of steel fibers to produce green, low-cost and sustainable UHPC. The process of extraction and treatment of the DPFs before incorporating it into the mix design was discussed. Several concrete samples were prepared with different weight percentages of DPFs as a partial replacement of steel fibers (from 0% to 25 wt.%). Compression strength, flexural strength, water absorption, and fresh/hardened densities were experimentally investigated. The morphology and the bonding interface between the fibers and cementitious composite were characterized by scanning electron microscopy (SEM). The results reveal that the DPFs has the potential to be utilized to produce UHPC with comparable performance to the traditional UHPC that is normally reinforced with steel fibers.

Green solvents for extractive separation of Pb(II) and Hg(II) from various resources-An update

Heavy metals such as lead and mercury pollution are irreversible and stay for long time.The handling of wastes come out of industries, agriculture, domestic uses is very difficult to deal with. Hydro metallurgical technique like solvent extraction offers huge scope for the extraction,separation and purification of these waste materials in order to extract these metal values. The feasibility of ionic liquid as green solvents in the recovery of heavy metal ions like Pb(II) and Hg(II) from diverse resources are analyzed in this review. Ionic liquids, or salts having low melting temperature , have a number of benefits, including being long-lasting and environmentally friendly green solvents. Because of their specific attributes, like low vapour pressure, inflammability, less toxic character, appreciable ionic conductivity as well as a broad electrochemical potential window, these have got numerous application into diverse sectors, including hydro metallurgy. Despite the fact that a number of papers have been published on ionic liquids, pertinent research outcomes in the area of hydro metallurgical methods are very less. Due to the fact that investigation and use in this area are still in its early stages,more fundamental approaches to popularize these green solvents in the metal processing industries will be more challenging.Ammonium and phosphonium based ionic liquids have more stability than imidazolium based ionic liquids.Extraction process parameters like pH, time of extraction, extractant concentration, optimum temperature, volume ratio of both aqueous and organic phases in different extraction systems and their influences the extraction efficiency have been summarized.

Optimal preparation time in the vermicompost production process

Today, the vermicompost production process is considered one of the most economically, hygienically, and environmentally friendly methods for the stabilization of organic waste. The aim of this paper was to investigate the effect of food waste preparation time without initial modification and without continuous aeration on the vermicompost process before feeding the worms with organic waste material in order to pass the calorific stage of decomposition of organic matter and not to damage the worms that are sensitive to high temperatures, and the process of fertilizer production is faster, organic matter is composted for a while without the presence of worms. In this paper, four periods, including 0, 7, 14, and 21 days of waste preparation, were examined. The results showed that the difference in ratio between different preparation times was significant 7-14 days the most suitable time for waste preparation without initial modification was obtained.

Nonconventional yeasts to produce aroma compounds by using agri-food waste materials.

Nowadays, biotechnological applications are emphasized to ensure sustainable development by reutilizing waste materials to prevent ecological problems and to produce or recover compounds that may have positive effects on health. Yeasts are fascinating microorganisms that play a key role in several traditional and innovative processes. Although Saccharomyces is the most important genus of yeasts, and they are major producers of biotechnological products worldwide, a variety of other yeast genera and species than Saccharomyces that are called 'non-Saccharomyces' or 'nonconventional' yeasts also have important potential for use in biotechnological applications. Some of the nonconventional yeast strains offer a unique potential for biotechnological applications to produce valuable secondary metabolites due to their characteristics of surviving and growing in such extreme conditions, e.g. wide substrate range, rapid growth, thermotolerance, etc. In this review, we aimed to summarize potential biotechnological applications of some nonconventional yeasts (Kluyveromyces spp., Yarrowia spp., Pichia spp., Candida spp., etc.) to produce industrially important aroma compounds (phenylethyl alcohol, phenylethyl acetate, isobutyl acetate, diacetyl, etc.) by reutilizing agri-food waste materials in order to prevent ecological problems and to produce or recover compounds that may have positive effects on health.

Use of discarded aluminium foil in cementitious material as fire retardant - An experimental study

Minimal greenhouse gas (GHG) emissions and lower fuel consumption are critical aims for current manufacturing industries. The construction industry is indisputably responsible for 11% of global carbon dioxide (CO2) emissions, including 5% of CO2 from the cement industry. Alkali-activated cement (AAC) was introduced in the early 1980s to reduce GHG emissions and unsustainable energy requirements. However, the properties of AAC are still being improved with the addition of different supplementary cementitious materials. In addition, manufacturing industries aim to utilize waste materials in order to reduce environmental pollution and landfill. Therefore, to meet both needs, this study focuses on the utilization of waste material to improve the mechanical properties of AAC. Rice husk ash (RHA) is a familiar alternative silica source and its role as a fire resistant up to 600 °C is shown in this study. Discarded aluminium (Al) foil enhances the compressive strength of RHA-based samples by 80% and acts as setting retarder and fire retardant. Emission and cost analyses show that the production of Portland cement emits as much as 125% more CO2 and costs 1.5 times as much as RHA-based composite. Overall, Al-RHA-based cement production reduces issues related to GHG and waste utilization, and its production emits hydrogen gas as a by-product, a future fuel source, equivalent to 3% of global annual hydrogen demand.

Management of Construction and Demolished Waste as an Aggregate Substitute in Cement Concrete

India is in the process of modernization in the construction sector by repairing, renovation, up-gradation. Presently concrete, the universal building materials whose main ingredient is coarse aggregate. The local natural resources like stone products and sand may exhaust and put the sector deficient of aggregates. The wise use is to reuse recycled concrete and demolition wastes generated from the construction sectors due to shift from horizontal to vertical growth of urban areas. The replacement of recycled coarse aggregate shall efficiently organize the waste management, moderate the environment degradation, and upsurge sustainability.
 Use of recycling material in the construction industry as a recycled concrete is highly challenging. So our project deals about reusing of demolished concrete blocks from C &D wastes by form of Recycled coarse aggregate (RCA) are replacing the Natural coarse aggregate in concrete and use in the construction industry. The replacement of RCA in special concrete of 7 and 28 days of curing and the various physical and mechanical properties of materials and strength test of both concrete such as workability, compressive strength, split tensile strength and flexural strength. The test value are compared both in concrete.
 Our project investigates on recycling demolished waste materials in order to reduce construction cost and resolving housing problems faced by the low-income communities of the world. The crushed demolished concrete wastes is segregated by sieving to obtain required sizes of aggregate, several tests were conducted to determine the aggregate properties before recycling it into new concrete.

Characterization of Blends of Virgin Nitrile Rubber and Compounded Nitrile Rubber Latex Waste Reclaimed with Urea: Part II - Physico-Mechanical Properties

Recycling of rubber waste materials in order to convert these to usable products is one of the main challenges in the rubber industry. Reclaiming of rubber waste and blending it with virgin rubber have increased during the past due to the growing concern on the environment and increase in the prices of synthetic rubbers. Hence, the aim of this study is to partially replace virgin nitrile rubber (NBR) with reclaimed compounded NBR latex waste to develop new rubber blends suitable for special applications. In this study, physico-mechanical properties, ageing performance and swelling behaviour of virgin NBR / reclaimed NBR blend vulcanizates were evaluated and compared with those of the control vulcanizate produced solely with virgin NBR. Results showed that replacement of 50% virgin NBR with reclaimed NBR retained 71-86% of tensile strength, elongation at break and resilience. Hardness and modulus of this blend vulcanizate increased by less than 18%, whereas abrasion volume loss and compression set increased by 27%. Ageing resistance is similar to that of the control vulcanizate. Interestingly, resistance to swelling in toluene and ASTM oil No.3 increased by 14% and 32%, respectively. Hence, the 50:50 virgin NBR / reclaimed NBR vulcanizate would be suitable for oil resistant applications.

PYROLYTIC RECOVERY AS A PROSPECTIVE USE OF PLASTIC WASTE MATERIALS

Prospective use of plastic material components resulting from their pyrolytic recovery is presented in the paper. Selected plastic waste materials (PE, PP, PS) were evaluated using modern analytical method GS-MS after the low-temperature pyrolysis. The low-temperature pyrolysis shows that the sample of PS was well-suited to this application and this recovery is important in the case of all three samples as well. The presence of 26 substances with 1-Hexene (13.72%) was observed in the case of pyrolysis products, specifically PE. When investigating PP, 36 substances with the highest content of 2.4-Dimethyl-1-heptene (38.35%) were defined. 20 substances containing especially Styrene (79.97%) were determined as the major products of PS pyrolysis. Moreover, using the GC-MS analysis, it was found out that chemical compounds present in all samples could be further recovered. The possibility of using the pyrolysis to recover the plastic waste materials in order to protect the environment is necessary.

Geo-polymerization technique for brick production from coal ash and cigarette butts

Innovative approaches are under research to produce sustainable bricks from waste materials in order to minimize the significant environmental impacts of conventional brick industry. In this study, geo-polymerization technique was used for the first time to produce sustainable light-weight bricks from cigarette butts (CBs) and coal ash. Various Na2SiO3: NaOH and coal ash: activation liquid ratios were studied to be able to obtain well-formed bricks. The CBs were added in coal ash in two ways: either in dry form or previously soaked in the activation liquid before they were mixed with the coal ash. The percentage of CBs mixed in coal ash was varied between 5% and 15%. The density, compressive strength and water absorption capacities of the geo-polymer bricks were elucidated at time intervals of 7, 14 and 28 days. The results showed that, bricks produced with Na2SiO3: NaOH ratio of 2:1, (coal ash and CBs): activation liquid ratio of 3.5:1 and 15% treated CBs achieved a low density (1563 kg/m3) while sustaining its compressive strength (11.1 MPa) complying with the standards. In addition, lower water absorption was obtained with the bricks containing treated CBs in comparison to the ones with untreated CBs. In conclusion, geo-polymerization shows a high potential as a sustainable method for the light-weight brick production from CBs and coal ash.

Environmental Factors Affecting the Strength Characteristics of Modified Resin Mortars

Resin concretes are composites in which a cement binder has been completely replaced by a synthetic resin. These materials are a good choice for the construction industry, especially in solutions requiring high strength, fast curing and durability. Polymer mortars are mainly used for the manufacture of industrial floors and prefabricated products such as tanks for aggressive chemicals, sewage pipes, or road and bridge drainage systems, as well as for the repair of damaged concrete structures. In all these applications, the strength and high chemical resistance of the applied material solutions are of key importance. It is particularly crucial to obtain information on how resin composites behave when exposed to aggressive agents over extended periods of time. It is also very important to use waste materials in order to obtain resin composites, as these activities are very well inscribed in the idea of environmental protection and meet the criteria of sustainable construction. The mortars described in this article meet the above principles. The article presents how the compressive strength of glycolyzate-modified epoxy mortars, obtained with the use of poly(ethylene terephthalate), changes after they are immersed in 10% sodium chloride solution. Sodium chloride solution was chosen due to the prospective applicability of the tested composites as repair materials used for e.g. bridges or overpasses that are exposed to this salt solution in wintertime. Changes in the properties of the composite samples were monitored over the period of one year. Statistical analysis of the test results was carried out with the use of Statistica programme. The module available in the mentioned program called Nonparametric Statistics - Comparing multiple independent samples made it possible to check the monitoring times during which the compressive strength values differed significantly. The obtained results allowed for determining the equation of the function approximating the course of changes in mortar properties. The designated parameters of regression equations can be used to project the properties of composites.

Numeric Evaluation of Kinematic and Dynamic Characteristics of Mineral Treatment in Disintegrator

The numerical modeling provides a holistic picture of mechanical treatment and activation of substances in a disintegrator. The authors calculate kinematic and dynamic characteristics of elastic and inelastic collisions in terms of halite, quartz and sulfur particles and disintegrator fingers. The recommendations on selecting optimal treatment conditions for natural minerals and waste material in order to dissociate mineral concretions and for selective activation of minerals are given. The research findings can partly be used for other types of percussion disintegrating devices, in particular, jet mills.

A CRITICAL REVIEW OF DRILLING WASTE MANAGEMENT TOWARDS SUSTAINABLE SOLUTIONS

Drilling waste management for oil and gas industry involves collection, transportation, processing, recycling, disposal, and monitoring of waste materials in order to reduce their effects on health and environment. In the Exploration and Production industry, environmental concerns have made effective management of drilling waste at well sites a great priority. Effective waste management is thus a key element in a successful drilling project. The industry therefore relies on effective expertise and newer technologies to maintain a balanced trade-off between healthy business activities and environmental effects. Over several decades, the industry has recorded remarkable progress in reducing the effects of drilling activities on the environment. The progressive development and adoption of sustainable drilling waste management protocols by operating and servicing companies have been partly responsible for this success. However, new challenges are emerging due to advances in drilling techniques such as extended reach wells, deep water drilling, multi-lateral drilling, and high-pressure wells. Recently, advanced drill waste treatment methods such as nanotechnology based approach, supercritical fluid extraction, and microwave treatment process have been explored and tested in the laboratory and on pilot scale to see if they can help overcome these challenges and increasingly stringent regulations. This paper reviews the shortcomings of the conventional approaches, their treatment technologies, advantages, and applications. This article enhances understanding of waste management and its treatment process based on sustainability concept. Researchers can find this review useful as an update on the state of drill waste management in the oil and gas industry. It can also serve as a useful guide to develop new rigorous sustainable models, protocols, and techniques to manage drilling waste using the noble concept.

Optimization of Polymer-Amended Fly Ash and Paper Pulp Millings Mixture for Alternative Landfill Liner

In 2012 the City of Flagstaff partnered with researchers at the Dept. of Civil and Environmental Engineering at Northern Arizona University to successfully develop a mix design utilizing sludge derived from the manufacturing of recycled paper pulp sludge (PPS) and fly ash as a component of a landfill cap. This research has been extended to explore the addition of polymers to the mix of waste materials in order to optimize a design that would be suitable as a component for an EPA Subtitle D-approvable landfill liner. Cinder Lake Landfill (CLL) serves several communities in Northern Arizona and is managed by the City of Flagstaff. CLL does not have a reliable source of clay needed to construct a required landfill liner, which is necessary for the upcoming 108-acre landfill expansion. However, CLL receives approximately 80 tons of recycled PPS daily from the local tissue manufacturing plant. PPS is currently used as daily cover and was tested for use as part of a landfill cap, as noted above. Incorporating polymers in alternative materials such as PPS and fly ash has the potential to meet performance criteria and be approved by state and federal regulators, and has the potential to save the City millions of dollars over conventional composite liners of geomembrane and clay. Different mixtures of PPS, fly ash and three different polymers are currently being subjected to testing for the following: Water Content, Specific Gravity, Porosity, Organic Content, Atterberg Limits (plasticity), Proctor Compaction, Consolidation, California Bearing Ratio, Shear Strength, Gas Permeability, and Liquid Permeability. The optimal mixture of PPS and fly ash will be blended with a range of polymer concentrations. The goal is to find an optimal mix of PPS, fly ash, and polymer to achieve regulatory standards related to permeability, along with other desirable properties such as strength and flexibility. The optimum mixture(s) will then be subjected to field trials, scheduled to begin in 2016, in which test cells will be created at CLL. The liner will be constructed with the optimized mixture(s), and the cells will be operated as landfills for 1-2 years. Results from lab and field testing will be submitted to federal and state regulators for consideration as an alternative liner approach.

Effect of granulated lead smelter slag on strength of fly ash-based geopolymer concrete

Geopolymer concretes are manufactured from high-volume industrial waste materials in order to produce concrete that is low energy consuming, has a low carbon footprint, is sustainable and Portland cement-free. This paper presents an experimental study on the manufacture and behaviour of geopolymer concrete produced with a combination of granulated lead smelter slag (GLSS) and fly ash. The experimental program included 32 mix designs to investigate the influence of: fly ash replacement with slag as a binder, washed river sand replacement with slag as a filler, slag particle size to reactivity, alkaline activator-to-binder ratio, and curing period. It was found that incorporating 75% of slag as fly ash replacement and 100% of slag as fine aggregate produces concrete exhibiting compressive strength of 31MPa. It was also found that significant improvements in the compressive strength of the hardened concrete (i.e., from 6MPa to 65MPa) could be obtained by super fine crushing the slag to a fineness similar to Portland cement and fly ash (<20μm). The results showed that the mechanical properties of the fly ash/slag-based geopolymer concrete were similar to that of fly ash-based geopolymer concrete, whilst the drying shrinkage of geopolymer concrete containing high volume of GLSS was lower than that of fly ash-based geopolymer concrete.

Strength and Strain Properties of Concrete, Comprising Filler, Produced by Screening of Waste Crushed Concrete

The presented paper is dedicated to the topical issue of utilization of screenings waste crushed concrete, which is produced as a result of crushing of waste materials, formed during dismantling buildings and facilities, and a production of fine aggregate concrete on its basis. The paper presented analysis of economic situation in the region and results of the study of screened waste materials in order to increase efficiency of an application of that product as fine aggregate and fine-ground active filler for a production of fine aggregate concretes. Particle size distribution, mineral and chemical composition of waste crushed concrete were studied, as well as features of their structure, taking into account heterogeneity of crushed material. Transitional zone of secondary aggregate and cement matrix was studied and it was proved, that the strength of adhesion with cement matrix of grains of that kind of secondary material, produced from screenings of waste crushed concrete, is significantly higher, than strength of the grain itself, which is indicative of an active influence of that aggregate on a formation of both characteristics of structure of cement matrix and dense transitional zone between them. Optimal composition of multicomponent binders, comprising fine-ground filler, produced from screenings of waste crushed concrete, is designed. Compositions and properties of cement matrix based on the designed binders are studied. Compositions of concretes, based on multicomponent binders with anthropogenic filler, are obtained and their strength and strain properties are studied.

Photodegradation of the anthraquinonic dye Acid Green 25 by TiO2 immobilized on carbonized avocado kernels: Intermediates and toxicity

The aim of this research was to develop a TiO2 composite from a waste material in order to study the photocatalytic decomposition of an important residual anthraquinonic dye. Carbon-TiO2 composites were obtained from carbonized avocado kernels and sols of TiO2 prepared from NH4OH and TiCl4 using glycerol as a binder and thermally treating the composites at 500°C. XRD studies confirmed the anatase phase of TiO2. SEM images showed isolated TiO2 agglomerates attached on the carbon surface with a Ti:C ratio of 1:3.3 established by EDS semi-quantitative analysis. The photocatalytic activities of the prepared composites were tested in a decomposition assay of Acid Green 25. Titanium dioxide and the composite eliminated almost 100% of the dye under UV irradiation and the composite demonstrated degradation efficiency under solar light. The reaction was monitored by UV–vis spectrophotometry and by LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. No evidence of toxic effects was found in the dye AG25 and its photodegradation products, which were evaluated on the plant growth-promoting bacteria Azospirillum brasilense.

Effect of amendments made of waste materials in the physical and chemical recovery of mine soil

The process of obtaining minerals required by society entails a series of impacts caused by mining. In order to minimise these impacts, amendments have now been used for several years made of waste material in order to recover mine soils. Two amendments were used in this experiment: A1 (a mixture of sludges from a bleach plant, urban solid waste and material from the area around the mine) and A2 (sludge from a purification plant, wood chips and remnants from agri-food industries). These amendments can improve the characteristics of the mine soils by increasing their pH and concentrations of carbon and nutrients, as well as reducing the concentration of metals in bioavailable form. However, the use of wastes can add metals to soils; so it is important to control their concentrations before being used. With the aim of knowing how these amendments perform over time, an experiment was carried out in plant pots, amending a soil from the settling pool from a former copper mine located in Touro, in north western Spain. The pseudo-total and DTPA-extractable concentration of metals, nutrients in phytoavailable form and pH of the soil were measured over a 3-month period. At the end of the experiment, it was found that both amendments caused in increase in the pH and concentrations of basic cations, carbon, and humic and fulvic acids. The amendment made of solid urban waste (SUW) caused an increase in the concentration of DTPA-extractable Pb and Zn. For these reasons, when applying these amendments it is important to take into account to which types of soils they can be applied. To amend this mine soil, the materials used in the amendments A1 and A2 would be valid, as the soil from the pool is already contaminated by metals and cannot be used for agricultural purposes.