Huge Amount Of Solid Waste Research Articles

A novel recycling route for aluminum alloys: Synthesis of Fe/Al bimetallic materials and magnetic separation

Aluminum (Al) is one of the most important non-ferrous metals used in modern society, but its production from primary ores (e.g., bauxite) requires high energy input, emits large CO2, and generates huge amounts of solid wastes. In contrast, the production of Al from recycled scrap—also known as secondary Al production—only requires 5–8% of the energy for producing Al from bauxite and generates less amount of solid waste than that of the primary Al production, thus having both economic and environmental benefits. In general, scrap Al alloys are treated by physical-based separation techniques to remove impurities, and then mixed aluminum alloys are charged into the furnace for further refining. The ideal way of recycling Al scrap is to process each Al alloy by remelting/refining processes. To this end, this study investigated the surface modification of aluminum alloys by iron (Fe) deposition, followed by their separation by magnetic separation.When Al powder was treated with an acidified ferrous chloride solution (FeCl2-HCl-NaCl solution), dissolved Fe concentration decreased with time while releasing Al3+ into the solution, indicating that Fe cementation on Al occurred. X-ray photoelectron spectroscopy (XPS) analysis of treated Al powder showed that its surface was covered with zero-valent iron (ZVI) as well as its oxidation products (e.g., Fe(II)/Fe(III)-oxyhydroxide). The synthesis of Fe/Al bimetallic materials from Al alloys—1050, 2024, 3003, 5083, 6061, and 7075—was strongly dependent on HCl concentration as well as reaction temperature. Moreover, the kinetics of Fe cementation on Al alloys and the amounts of Fe cemented were determined not only by the rest potentials of the Al alloys but also their corrosion resistance. After treating Al alloys with FeCl2-HCl-NaCl solution, each Al alloy could be sequentially recovered by magnetic separation.

Engineered cementitious composites using powder regenerated from municipal solid waste incineration bottom ash as supplementary cementitious material

Ecotype Engineered Cementitious Composites (ECC) can not only consume a huge amount of solid waste, reduce environmental pollution and human damage, but also reduce the high production cost of such materials. In this research, municipal solid waste incineration (MSWI) bottom ash was used to develop economical and applicable ecotype ECC. Firstly, the physical and chemical properties of MSWI bottom ash with different particle sizes were analyzed, and the bottom ash particles with high reactivity were screened out and ground into powder. Then the uniaxial tensile and four-point bending tests were used to study the mechanical strength and strain-hardening properties of ECC containing bottom ash powder. The results present that the powder milled by bottom ash particles with the size of 2.36–9.5 mm has finer particles and higher reactivity. The optimal ratio of bottom ash powder to cement for ECC can be determined as 2.2:1. Here ECC not only has high mechanical strength but also exhibits wonderful strain-hardening properties and multiple micro-cracking capacities. The increase in fiber content and water-binder ratio is beneficial to the development of excellent ductility. This study provides a strategy to produce low-cost ecotype ECC by using MSWI bottom ash powder as supplementary cementitious materials.

From leather wastes to leather: enhancement of low quality leather using collagen recovered from leather tanned wastes

Leather industry produces huge amounts of solid wastes. In the last decade, several methods for the recovery and valorization of these wastes were developed, mainly focused on the extraction of collagen using chemical methods. The extracted collagen, due to its poor quality, is mostly used in agriculture as a nitrogen source ingredient of fertilizers. This study aims to apply collagen, extracted from leather tanned solid wastes using a recently reported new process based on enzymatic hydrolysis, as filling agent for low quality leather. Thanks to the enzymatic hydrolysis, collagen can be extracted without affecting its integrity and, therefore, its quality. In order to use the extracted collagen as filler for low quality leather, an enzymatic mediated cross-linking reaction between collagen and casein was developed. The enzymatic cross-linking reaction was added as an additional phase of the re-tanning process or as a replacement of one of the re-tanning steps. To evaluate the filling effect, thickness of the treated leather was measured and infrared and microscopy analyses were performed, comparing the new methods to the traditional standard one. The mechanical properties of the filled leather were tested and the sensorial features, such as fullness and touch feelings, were estimated through a panel test. Results suggest the high potential of extracted collagen to be employed back in leather processing both as additive and as substitutive filler.Graphical abstractAims and goals of the research study: comparison between re-designed (green workflow) and traditional re-tanning process (grey workflow).

Valorization of Pelargonium graveolens L’Hér. Hydrodistillation Solid Waste as Natural Dye for Wool Fabrics

ABSTRACT The huge amount of solid waste produced during the hydrodistillation of Pelargonium graveolens L’Hér. is a serious environmental hazard. The aim of this research is to reduce this environmental pollution and to valorize this waste by using its extract as a natural dye. Extracts were used for dyeing wool samples. The dyed fabrics showed shades ranging between brown and beige. By using the Minitab 19 Software, a definitive screening design was used to optimize the dye extraction process. The studied extraction process parameters were pH, temperature, and extraction time. The main studied responses were the color strength and the polyphenol, flavonoid, and condensed tannin contents (mg.g−1). Based on the photochemical study and the UV–vis absorption spectra, it was found that the polyphenol content varies between 4.144 and 7.567 mg.g−1. For the tannin content, the highest value was equal to 120.967 mg.g−1. To optimize the colorant extraction process, the K/S was also measured by the spectrocolorimeter. Process optimum conditions were of 11, 100°C, and 65 min, respectively, for pH, temperature, and extraction time. The optimum K/S value was equal to 115.15. Therefore, the solid waste hydrodistillation of Pelargonium graveolens can be an interesting choice for the natural dyeing of textile fabrics.

Prospect of Essential Oil Industrial Waste as Energy Resources for Essential Oil Production Process

Essential oil production produces huge amount of solid waste. This un-utilized waste potentially causing environmental problems. Converting the waste into biomass briquettes (bio briquette) is one of the prosperous solutions since the briquettes can be used as energy source for the production activities in those industry. The objective of this study is converting the solid waste of essential oil production from nutmeg and clove stems into bio-briquette form, and to analyze the potency of those bio-briquette to fulfill energy demand for essential oil production process itself. Several various compositions have been taken to get best performance of the bio-briquettes as fuel. The ratio of mass and adhesive were 1:0.625; 1:0.75; 1:1; 1:1.25 for nutmeg cakes, 1:0.75; 1:0.825; 1:1; 1:1.25 for nutmeg shell charcoal, and 1:0,5; 1:0.625; 1:0.75; 1:1 for clove stem charcoal. The best results was performed by nutmeg shell charcoal briquettes with composition of 1: 1. This briquette has moisture content of 6.64%, ash content of 3.31%, and a calorific value of 5497 cal/gram. Those specification meets the requirements of SNI 1/6235/2000 regarding briquettes as a fuel. Based on energy demand calculation, implementation of those briquettes as fuel will reduce annually solid fuel consumption around 30%. The reduction will help to reduce essential oil production cost, and help the product to get “green product” label, which is very important for all products in the global market.

Three “R” Concept in Waste Management for Sustainable Environment

The dawn of the 21st century has thrown several challenges to mankind. The most dangerous among the challenges is the maintenance of a sustainable environment. While anthropogenic activities are considered as the predominant cause for environmental pollution, the solution also lies with human beings only. Here comes the role of the Three “R” concept which has been widely adopted across the globe. The Three “R” concept talks about Reducing the waste, Reusing the waste, and Recycling the waste and products to the extent possible. Today, a developing country like India generates a huge amount of solid waste, sewage, electronic waste, and gaseous pollutants. When we adopt this Three “R” Concept, the ill effects of the pollution caused by these agents can be effectively mitigated. Indeed, the various pollution control bodies of the governments are vigorously propagating the Three “R“ concept among the highly polluting industries to bring down the carbon emission to the sustainable level. Indeed, this is one of the United Nations Sustainable Development Goals (UNSDG). This new paradigm will definitely yield the desired result in developing and maintaining a sustainable environment which ensures the availability of pristine natural resources for the generations to come. The Higher Educational Institutions (HEI) play an important role in sustainability promotion in society. Waste management is one of the challenges educational institutions have to face in accomplishing the sustainability goals. KARE adopts the Three “R” Concepts in managing the solid, liquid, biochemical, and e-waste resulting in the development of a sustainable and eco-friendly environment on the campus. This poster details the recycling of solid, liquid, biochemical, and e-waste on Kalasalingam University campus. The solid wastes generated are converted into wealth and reused in the form of Vermicompost which is eco-friendly, the liquid waste is reused after treatment, paper and e-waste are recycled or reused through vendors. Further, the bio-medical/biochemical wastes are disposed of as per the government norms. Keyword: Reduce, Reuse, Recycle, Sustainable Development Goals (SDG), Eco-friendly

Enrichment of residual carbon from coal gasification fine slag by spiral separator

Coal gasification is one of the most promising clean coal technologies. However, gasification process also produces a huge amount of solid waste of high carbon content, named coal gasification fine slag. The coal gasification fine slag is mainly handled by landfilling, which is not only a hazardous pollution, but also wasting the energy from residual carbon. Developing a technology to utilize coal gasification fine slag and recover the residual carbon is becoming essential for an eco-friendly coal chemical industry. In this paper, the enrichment behavior of residual carbon in coal gasification fine slag by a spiral separator is studied. The raw coal gasification fine slag sample and separator products are characterized on particle size distribution, size-depending ash content, reactivity, micromorphology and porous structure. The experimental results show that the spiral separator is efficient to remove ash and enriched carbonaceous components in coal gasification fine slag by separating feed (100%) into concentrate (81.2%), middlings (8.8%), and tailings (10.08%), where the ash content in tailings is up to 90%, accounting for 18.5% of total ash in feeding. The beneficial product “concentrate” has a good distribution of size-depending ash content, that most combustibles are enriched in these particles of diameter >100 μm. After spiral separator, the concentrate products have a more pure and developed porous structure with the surface area increasing from 199.8 m2/g (feeding) to 231.8 m2/g, as well as a better combustion reactivity of lower ignition temperature compared with feedings. Accordingly, an economic and feasible combination process of spiral separator connecting sieve can produce an enriched-carbon product of ∼45% yield and ∼80% carbonaceous content. The Iodine adsorption ability of sieved products increases by 47.6% compared with feed, and reaches up to about half of industry activated carbon. The finally sieved concentrate products have a good market prospect as fuel and adsorbent.

Bioactive Compounds in Waste By-Products from Olive Oil Production: Applications and Structural Characterization by Mass Spectrometry Techniques.

In recent years, a remarkable increase in olive oil consumption has occurred worldwide, favoured by its organoleptic properties and the growing awareness of its health benefits. Currently, olive oil production represents an important economic income for Mediterranean countries, where roughly 98% of the world production is located. Both the cultivation of olive trees and the production of industrial and table olive oil generate huge amounts of solid wastes and dark liquid effluents, including olive leaves and pomace and olive oil mill wastewaters. Besides representing an economic problem for producers, these by-products also pose serious environmental concerns, thus their partial reuse, like that of all agronomical production residues, represents a goal to pursue. This aspect is particularly important since the cited by-products are rich in bioactive compounds, which, once extracted, may represent ingredients with remarkable added value for food, cosmetic and nutraceutical industries. Indeed, they contain considerable amounts of valuable organic acids, carbohydrates, proteins, fibers, and above all, phenolic compounds, that are variably distributed among the different wastes, depending on the employed production process of olive oils and table olives and agronomical practices. Yet, extraction and recovery of bioactive components from selected by-products constitute a critical issue for their rational valorization and detailed identification and quantification are mandatory. The most used analytical methods adopted to identify and quantify bioactive compounds in olive oil by-products are based on the coupling between gas- (GC) or liquid chromatography (LC) and mass spectrometry (MS), with MS being the most useful and successful detection tool for providing structural information. Without derivatization, LC-MS with electrospray (ESI) or atmospheric pressure chemical (APCI) ionization sources has become one of the most relevant and versatile instrumental platforms for identifying phenolic bioactive compounds. In this review, the major LC-MS accomplishments reported in the literature over the last two decades to investigate olive oil processing by-products, specifically olive leaves and pomace and olive oil mill wastewaters, are described, focusing on phenolics and related compounds.

Utilization of Solid Waste from Brick Industry and Hydrated Lime in Self-Compacting Cement Pastes.

The huge amount of solid waste from the brick manufacturing industry can be used as a cement replacement. However, replacement exceeding 10% causes a reduction in strength due to the slowing of the pozzolanic reaction. Therefore, in this study, the pozzolanic potential of brick waste is enhanced using ultrafine brick powder with hydrated lime (HL). A total of six self-compacting paste mixes were studied. HL 2.5% by weight of binder was added in two formulations: 10% and 20% of waste burnt brick powder (WBBP), to activate the pozzolanic reaction. An increase in the water demand and setting time was observed by increasing the replacement percentage of WBBP. It was found that the mechanical properties of mixes containing 5% and 10% WBBP performed better than the control mix, while the mechanical properties of the mixes containing 20% WBBP were found to be almost equal to the control mix at 90 days. The addition of HL enhanced the early-age strength. Furthermore, WBBP formulations endorsed improvements in both durability and rheological properties, complemented by reduced early-age shrinkage. Overall, it was found that brick waste in ultrafine size has a very high degree of pozzolanic potential and can be effectively utilized as a supplementary cementitious material.

Experimental study on the durability properties of Shahabad stone waste as partial replacement of coarse aggregate in concrete

The effect of using Shahabad stone waste as partial replacement of coarse aggregates on durability properties is investigated in this work. This work aims at utilizing Shahabad stone waste in concrete as a building material in concrete to increase the strength and durability properties of the concrete. Shahabad stone waste was used as partial replacement of coarse aggregates. The stones used are calcareous in nature. The dressing of this calcareous stone produces huge amount of solid waste of sizes which range from 5 mm to 150 mm size. As projected by TIFAC [1] in the year 2005 about 188.6 million tonnes of solid waste was produced by mining and dressing sites, out of which 1/3rd of the total waste produced is Shahabad stone waste in India. The coarse aggregates in concrete is replaced with 20 mm size Shahabad stones. Experimental study was done by replacing 10%, 20%, 30% and 40% of coarse aggregates using Shahabad stones in M25 grade concrete. Durability tests were conducted and the results are presented here. It was found out that the results have proven that 30% is the optimum replacement in terms of strength as well as durability and hence Shahabad stone waste can be successfully used as partial replacement to coarse aggregate in concrete.

Geochemical Features of Unburned Coal Particles in Fly Ashes from Thermal Power Plants in Bulgaria

Coal combustion in thermal power plants generates huge amounts of solid wastes, including fly ash (FA). The essays of its conversion into value-added products continuously increase. The aim of the study was: (i) to depict organic compounds (if any) present in industrial coal-derived FAs from four thermal power plants (TPPs) in Bulgaria; (ii) to assess the relationship of the compounds present with the feed coals using biomarker proxies; (iii) and, to appreciate biomarkers changes in distribution pattern caused by combustion. Average samples of FAs and samples from electrostatic precipitators of four TPPs feed by different rank coals were analyzed. The study was scheduled in comparison with parent feed coals. The yields of extractable organic matter (EOM) expressed in rel. % were low and comparable, ∼ 0.01%, but normalized to total organic carbon (TOC) depicted some differences. For lower rank coals FAs yields were higher, in the range 10-20 mg/g TOC, all dominated by polar components and an order of magnitude lower for higher rank coal FAs, < 2 mg/g TOC, with considerable portions of neutral compounds. After extensive fractionation of EOM from unburned coal particles in neutral fractions of FAs short chain n-alkanes (nC15-nC19) prevalence was distinguished. The feature was assigned to high temperature of combustion and thermal destruction of long-chain homologues (nC27-nC31). The distribution signatures for low rank coals kept some characteristics of parent coals while in the case of bituminous coal longer homologues were almost absent. The changes in n-alkanes distributions were rank depended and an attempt for explanation by FA particles porosity was done. For organic compounds registered in EOM of coal-derived FAs two provenances are supposed. The first group comes from the feed coals and the second one is formed in combustion processes or has changed distributions under the thermal treatment. Insofar as n-alkanes distribution signature was altered in combustion the origin should rather be assigned to the second group of components.

Recycling spent iron-based disposable-chemical-warmer as adsorbent for as(v) removal from aqueous solution

The use of iron-based disposable-chemical-warmer (DCW) produces huge amount of solid wastes every year (e.g. at least 2 million tons of solid waste every year for China and Japan only), which are directly abandoned as trash now. In this work, spent DCW was recycled as adsorbent for As(V) removal from water. For the first time, we elucidated that the spent DCW was a magnetic nanocomposite consisted mainly of Fe3O4 nanoparticles and vermiculite with large surface area (56.6 m2/g). The detailed morphology characterization revealed the formation of Fe3O4 nanoparticles on vermiculite's surface, with the average crystallites’ size estimated to be ~10 nm. The adsorbent exhibited superparamagnetism with a strong saturation magnetization value 40 emu /g, which can be utilized to recollect the adsorbent after water treatment. The As(V) adsorption isotherm conformed to Langmuir isotherm model with the maximum adsorption capacity of 130 mg/g under neutral pH and room temperature. The adsorption capacity for As(V) outperformed most of the reported adsorbents, which was attributed to the hybrid structure of the adsorbent. The adsorption kinetic curve was well described by the pseudo-second order model. The favorable pH for As(V) was below 8.0, and the adsorbent had good As(V) selectivity over common co-existing anions (SO42−, H2PO4−, and SiO32−). Moreover, the adsorbent could be readily regenerated using 0.1 M NaOH aqueous solution as eluting solution. The adsorption capacity towards As(V) was still over 85% after 10 consecutive adsorption-desorption cycles. This work provided an efficient way for recycling spent DCW with minimal efforts.

A Step Closer to Sustainable Industrial Production: Tailor the Properties of Nanocrystalline Cellulose from Oil Palm Empty Fruit Bunch

Abstract There is an imperative need to tackle the huge amount of solid wastes from the palm oil production. The current utilization of oil palm biomass and waste management were deemed ineffective to the economic and environmental development. We proposed a sustainable solution to the management of oil palm waste using empty fruit bunch (EFB) to obtain nanocrystalline cellulose (NCC). The diverse properties of NCC were largely attributed to the origin of biomass and the isolation method. This demonstrated the importance of investigating the process parameters in a quantitative manner to ensure the effective production and exploitation of NCC. Response surface methodology was adopted to analyze the interaction effects of size, yield and crystallinity on the NCC production. The size of the acid-hydrolyzed NCC ranging from 15–27 nm in width and 170–317 nm in length was confirmed through the scanning transmission electron microscopy. The crystallinity obtained from the experiments as developed by Box-Behnken design was in the range of 70.35–83.20%, where it exhibited an inverse relation with the hydrolysis yield of NCC in the range of 4.11–80.23%. Through investigating the correlation of responses, an optimum point was obtained at which the yield and crystallinity of NCC were the highest, while the size of NCC was the lowest. The good model reliability indicated that the tailoring of the properties of EFB-origin NCC is feasible, suggesting EFB as a highly promising alternative to alleviate the resource depletion of wood pulp in the development of bio-based material.

Selection of Suitable Site for Solid Waste Landfill : a case study in Kirkuk City, Iraq

Selection of a landfill site for solid wastes is considered one of the challenges for local governments and municipalities’ directorates in particular all over the world, simply because every single city produces huge amount of solid wastes (garbage’s) each day that come from homes, hospitals, schools, industry, offices and centers of markets. In this study, Kirkuk city has been selected as a case study to figure out the solutions for trash, bad odors in most of the neighbourhoods, groundwater pollution, harmful toxic wastes, etc. So, proper criteria selection is very important as a starting point of landfills to preclude unwanted long-standing effects. Otherwise the traditional process of site selection process is difficult because its time consuming and costly. An integration of Geographical Information System (GIS) and Expert Choices Process (ECP) method is best combined technique to solve complex decision making and to select based on the study area condition. Six criteria have been used to select potential suitable site landfill in Kirkuk city. It turned out that the highest criteria is the built up area and the lowest one is bearing capacity of soil (BCS). Moreover, the final produced map shows the suitable area for landfill siting The work purports to present methodology of this inquiry and objective can make impressive solve in global environmental change and its regularly supplies an efficacious operation to select the suitable site to landfill the solid wastes.

Impact of Purchasing Power Parity and Consumption Expenditure Rise on Urban Solid Waste Generation in China

The paper focuses on the socio-economic factors of municipal solid waste generation (MSWG) in China. China achieves a rapid economic development since the economic reforms adopted in 1978. The study shows that only 33percent of population lived in urban areas in 1985 that increased to 54 percent in 2014. Consumption expenditure rate increases to 3.96 percent and solid waste generation rose about 2.96 percent annually from 1990 to 2014. A huge amount of solid waste in urban areas causes serious environmental woes and human health hazards that are hindrance to sustainable urban development. The study aims at finding out the associational effects of purchasing power parity (PPP) and consumption expenditure rise (CER) on the solid waste production. The paper shows the negative association of purchasing power parity (PPP) and consumption expenditure rise with solid waste production and their relationship is significant at 5% level. In addition, rapid urbanization is positively correlated to consumption expenditure rise and it is significant at 5%level as well. I prepare the dataset using the extracted annual and national records of National Bureau of Statistics of China and World Data Indicator (WDI) from 2000 to 2015. I analyzed the data applying Correlation Matrix and Multiple Linear Regression Analysis. The findings will facilitate to formulate efficient solid waste management to sustainable urbanity.

Assessment of Dowel Bars Performance in Concrete Pavement Containing Crumb Rubber of Tires

Solid waste management is one of the big challenges facing most countries around the world. Reusing these wastes in construction project represent one of the most efficient ways to consume these wastes and reduces the demand on natural sources. The Crumb Rubber (CR) of tires is a source of a huge amount of solid waste that can be reused in construction projects such as paving of roads. The current research presents an experimental investigation for the dowel bars performance in rubberized concrete pavement. The research involves conducted pullout tests for dowel bars cast in concrete pavement contains a different percentage of CR particle (2%, 4%, and 6% of total aggregate) as partial or total replacement to aggregate on sieves No. 16 and No. 50. Four cases of dowel bars surface were investigated. The results of the study showed that adding CR particles to concrete can significantly reduce the bond between the dowel bars and surrounding concrete pavement which allows for more free movement of dowel bars and reduce joint lockup. The use of treated CR by NaOH solution with standard dowel bars (epoxy coated lubricant steel dowels) can give a superior reduction in pullout load. The reductions were 45%, 66%, and 83% in pullout load for the percentages of 2%, 4%, and 6% crumb rubber respectively compared with the reference mix.

Logistics network design to reuse second-hand household appliances for charities

Abstract The increased urban population, lifestyle change, diet change, as well as increased welfare level and life standards in urban societies have caused huge amount of solid waste in metropolitan cities. Solid waste process management in metropolitan cities is currently one of the significant problems in developing countries. Most of the studies in the literature are concentrated on reverse logistics for one type of product for recovery or remanufacturing process, and far too little attention has been paid to a reuse distribution network through charities. In this study, a framework is suggested to reuse the variety of household appliances to reduce municipal solid waste and help the low-income families. A single-objective mixed integer linear programming (MILP) model with uncertainty in the number of the products used by consumers is presented to optimize the reverse logistics network. The designed logistic network considered different recycling options such as recycling and repair and the centers called charity. In order to show the functionality of the presented model, a numerical example is solved by GAMS software to obtain the network structure with the optimum cost. The results confirm the applicability of the model by offering a great number of used products that can be transported and reused by affordable cost.

Impact of Indoor Air Quality by Incorporating Agricultural Waste Into Fired Clay Brick

The demand for edible oil from all over the world has generated a huge amount of solid waste. Due to that, the problem of disposal method has become a constraint by the authorities. Therefore, this study is focusing on the incorporation of palm kernel shell (PKS) into fired clay brick in terms of indoor air quality assessment. The brick was incorporated with 0% and 5% of PKS and fired at 1050°C with heating rates of 1°C/min. Preliminary analysis was conducted with X-Ray Fluorescence test to determine chemical composition of raw materials used in the study. A further experiment of indoor air quality was obtained by measuring gases emission of total volatile organic compound (TVOC), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), formaldehyde (HCHO) and particulate matter (PM10) in Walk in Stability Chamber with controlled temperature and relative humidity. All parameters were compared with Industry Code of Practice on Indoor Air Quality standard. The result shows that incorporation 5% of PKS into fired clay brick complied with the standard requirement for use as building materials. As the conclusion, the use of palm kernel shell as clay replacement could reduce the waste disposal in landfills whilst providing low-cost building materials.

Experimental Investigations on Building Derived Materials in Chemically Aggressive Environment as a Partial Replacement of Soil in Geotechnical Applications

Construction and associated demolition processes produce huge amount of solid waste, generally termed as construction and demolition waste (CDW). Management and proper disposal of these wastes is an area of prime concern for modern civil engineers. About 90% of all CDW is composed of building derived materials (BDM) obtained from concrete, bricks, and tiles from structural and non-structural elements of a building. The present study emphasizes on the use of virgin BDM, which conserves natural aggregate, reduces the impact on landfills, saves energy, and thus can provide significant cost benefit. Five types of BDM—crushed lightweight concrete (T1), crushed marble tiles (T2), crushed high strength concrete (T3), crushed normal portland cement concrete (T4), and crushed bricks (T5)—are characterised to assess their compatibility when used in conjunction with local soil. The soil, BDM and soil–BDM mixes are characterized from physical, mechanical, mineralogical, microstructural, and chemical aspects. These tests are then repeated for the aforementioned soil-BDM mixes after immersion in acids. Aggregate impact value (AIV) results on the five types of BDM indicate that T1 and T5 are poorly resistant to impact loads. However, T2, T3, and T4 show relatively better resistance to impact loads and satisfy the requirements for sub-base material standards. Shear strength studies show that the average optimum replacement of soil by BDM is in the range of 17–23% by mass. In order to test the compatibility of BDM in soils containing aggressive chemicals, the properties mentioned above are re-evaluated after exposing the BDM to aggressive chemical environments. The results indicate that the internal angle of friction (ϕ) of virgin BDM is found to vary significantly due to acid attack. The results of AIV after exposing the BDM to acids show that BDM are highly susceptible to chemically aggressive environment. The performance of all types BDM are affected by the presence of acids and appropriate measures must be adopted while using BDM in such chemically aggressive environment. These standards can be used as guidelines in the present study in the absence of specific standards for BDM applications.

Sustainable Way to Minimize the Solid Fabric Wastes using Peroxidase Extracts of Ipomoea palmate Forssk. and Saccharum officinarum L.

One of the major environmental problems currently existing in the Sri Lankan apparel Industry is the aggregation of huge amounts of solid fabric wastes. This study was conducted to find out the optimum time and concentration taken to decolorise solid fabric wastes and investigate reuse and recycle methods of fabrics in order to minimise the impact upon the environment. The decolorisation was practiced by the peroxidase extracts of Ipomoea palmate Forssk. and Saccharum officinarum L. which are abundantly found in home gardens of Kandy District and Kurunegala District. The purification of biomolecules was done by a novel yet simple method of purification known as Three-Phase Partitioning (TPP). Butanol-water solvent system was used in this method. The concentration of purified solvents was measured using Potassium Permanganate and were tested upon Polyester and Cotton fabrics. The decolorisation activity shown in I. palmate extract was higher than that of S. officinarum. The highest decolorisation capacity was shown for a concentration of 1.6375×10ˉ⁵ mol dm-1 of I. palmate extract, and a minimum time of 9 days was taken for complete decolorisation. For S. officinarum extract, it has taken a minimum time of 15 days for a concentration of 3.125×10ˉ⁶ mol dm-1. The decolorisation capability was measured using a standard colour matrix. A slight deviation of peroxidase contents was observed in the plant materials collected from Kandy District and in Kurunegala District. Without aggregating huge amounts of solid wastes to the environment it has been stressed out that using simple and cheap methods of managing the solid fabrics in sustainable ways can minimize the damage on the environment by this study. Keywords: Decolorisation, Solid fabric waste, Ipomoea palmate, Saccharum officinarum, Three phase partitioning