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Metagenomics has revolutionized access to genomic information of microorganisms inhabiting the gut of herbivorous animals, circumventing the need for their isolation and cultivation. Exploring these microorganisms for novel hydrolytic enzymes becomes unattainable without utilizing metagenome sequencing. In this study, we harnessed a suite of bioinformatic analyses to discover a novel cellulase-degrading enzyme from the camel rumen metagenome. Among the protein-coding sequences containing cellulase-encoding domains, we identified and subsequently cloned and purified a promising candidate cellulase enzyme, Celcm05-2, to a state of homogeneity. The enzyme belonged to GH5 subfamily 4 and exhibited robust enzymatic activity under acidic pH conditions. It maintained hydrolytic activity under various environmental conditions, including the presence of metal ions, non-ionic surfactant Triton X-100, organic solvents, and varying temperatures. With an optimal temperature of 40 °C, Celcm05-2 showcased remarkable efficiency when deployed on crystalline cellulose (> 3.6 IU/mL), specifically Avicel, thereby positioning it as an attractive candidate for a myriad of biotechnological applications spanning biofuel production, paper and pulp processing, and textile manufacturing. Efficient biodegradation of waste paper pulp residues and the evidence of biopolishing suggested that Celcm05-2 can be used in the bioprocessing of cellulosic craft fabrics in the textile industry. Our findings suggest that the camel rumen microbiome can be mined for novel cellulase enzymes that can find potential applications across diverse biotechnological processes. [ABSTRACT FROM AUTHOR]

This study focused on the co-fermentation of food waste and tissue paper to produce ethanol, which will eliminate the need for additional nitrogen sources and nutrients, thereby reducing production costs. In response to the inhibitory effect of the high concentrations of glucose present in mixed-substrate hydrolysates on xylose fermentation, a co-fermentation process using Saccharomyces cerevisiae and Candida shehatae was proposed. This approach reduced the fermentation time by 24 h, increased the xylose utilization rate to 88%, and improved the ethanol yield from 41% to 46.5%. The impact of external conditions and corresponding optimization were also analyzed in this process. The optimum conditions were a 1:3 ratio of Saccharomyces cerevisiae to Candida shehatae, a pH of 5, and shaking at 150 r/min, and by employing dynamic temperature control, the ethanol production was increased to 21.98 g/L. Compared to conventional processes that only use Saccharomyces cerevisiae, this method enhanced the ethanol yield from 41% to 49%. [ABSTRACT FROM AUTHOR]

The rapid increase in solid waste along with urbanisation, especially arising from the industrial and agricultural sectors, sparks concern from the public regarding their adverse impact on human and environmental wellness. Therefore, waste biorefinery is the current interest that aligns with the concept of 'waste-to-wealth'. The conversion of waste into valuable products such as cellulose nanocrystals (CNCs) is an alternative method of circular waste management as CNCs have various applications. Their non-toxicity, biocompatibility, excellent mechanical strength, and load-bearing properties render them a good reinforcement agent for packaging films, sensors, and scaffolds. Nonetheless, the lack of studies on the comparison of waste sources and the complex parameters for the extraction of CNCs hinders the development of CNC extraction from waste products. This review paper compares and organizes the information from previously published scientific papers and reports on waste product sources, methods, parameters, and environmental effects of the derivation of CNCs from waste. Previously, no thorough reviews have been done closely on the sustainability aspect of CNC extraction from waste products. Through this review, it shows that there is a positive trend where novel CNC extraction routes are discovered to improve the yield, environmental friendliness, performance, and cost. However, most of the studies did not specify the environmental impacts of the extraction routes, limiting their feasibility for conventional applications. [ABSTRACT FROM AUTHOR]

Composite materials have been widely used because of their superior properties compared to those of the original material. Separation of the constituent materials is not easy in the recycling process, and such an effort lowers economic viability. As such, this study employed a pyrolysis as a valorizing method for the composite material. Disposable paper cup waste (DPCW) was chosen as the model compound for paper-plastic composites. To offer green/sustainable features, CO2 was employed as a raw and reactive material in the pyrolysis process. It was proved that DPCW primarily composed of cellulose (outer layer) and polyethylene (inner layer). In the single-stage and multistage pyrolysis of DPCW, the CO2 reactivity in the homogeneous reaction of CO2 and DPCW-derived volatiles was not rapid. To accelerate the reaction kinetics governing the reactivity of CO2, the catalytic pyrolysis of DPCW over Ni/SiO2 was performed. The formation of syngas increases significantly, suggesting that CO2 reactivity was catalytically enhanced. The generation of syngas (enhanced by CO2) was inversely related to the DPCW oil generation, indicating that more carbon was assigned from the oil to the gaseous pyrogenic products. The study results would offer a strategic means to valorize paper-plastic composites and CO2 into energy through pyrolysis. [ABSTRACT FROM AUTHOR]

Xylanase finds extensive applications in diverse biotechnological fields such as biofuel production, pulp and paper industry, baking and brewing industry, food and feed industry, and deinking of waste paper. Here, polyethylene glycol (PEG)-phosphate aqueous two-phase system (ATPS) was applied for the purification of an alkaline active and thermotolerant xylanase from a marine source, Cladophora hutchinsiae (C. hutchinsiae). In the purification process, the effects of some experimental factors such as PEG concentration and PEG molar mass, potassium phosphate(K2HP04) concentration, and pH on xylanase distribution were systematically investigated. Relative enzymatic activity and purification factor obtained were 93.21% and 7.18, respectively. A single protein band of 28 kDa was observed on SDS-PAGE. The optimum temperature and pH of xylanase with beechwood xylan were 30 °C and 9.0, respectively. The Lineweaver-Burk graph was utilized to determine the Km (4.5 ± 0.8 mg/mL), Vmax (0.04 ± 0.01 U) and kcat (0.001 s−1) values of the enzyme. It was observed that the purified xylanase maintained 70% of its activity at 4 °C and was found stable at pH 4.0 by retaining almost all of its activity. Enzymatic activity was slightly enhanced with Na+, K+, Ca2+ and acetone. The highest increase in the reducing sugar amount was 53.6 ± 3.8, for orange juice at 50 U/mL enzyme concentration. [ABSTRACT FROM AUTHOR]

The research on the recovery of low-grade thermal energy carried away by boiler flue gas is significant for sugar mills. This paper designs a waste heat recovery system based on sugar plant flue gas, integrating absorption refrigeration cycle and the organic Rankine cycle, and the effects of nine working fluids on the system are investigated. The aim is to realize the multi-form conversion of energy. The performance of the system is evaluated in terms of energy, exergy, and economic metrics. Multi-objective optimization is performed with the method of the NSGA-II genetic algorithm. The results show that Butane is the most suitable working fluid for ORC. The exergy efficiency of the system is 32.125% before optimisation, with an increased space cooling capacity of 15820.56 MW per year for the sugar mill. The exergy destruction analysis of the system reveals that the generator accounts for the highest proportion of exergy destruction (50.8%). The entire system shows the LCOE is as low as 0.0406$/kWh under the optimized condition. The optimized system can obtain an estimated annual electricity sales revenue of $136,300, and the sugar mill can save $308,600 in cooling costs. In addition, the payback period can be shortened to 5.79years. [ABSTRACT FROM AUTHOR]

The current research focuses on the efficiency of energy recovery from non-hazardous organic wastes. It entails the generation of low-chloride refuse-derived fuel (RDF) from municipal solid waste (MSW) through moderate pyrolysis of combustible components. The moderate pyrolysis settings and composition ratio of biogenic/non-biogenic content from MSW combination (food waste, plastic waste, and paper waste) had a significant impact on the thermochemical characteristics and fuel behavior of RDF. Furthermore, pyrolysis with optimal MSW composition was studied to reduce toxic elements (chlorides, sulphides, and nitrides) and enhance the energy value in RDF by utilizing potassium-rich (waste orange peels (OP); banana peels (BP); and maize cob (MC)) and calcium-rich species (waste animal bone meal (ABM); egg shells (ES); and mussel shells (MS)) as natural additives. The results showed that increasing the pyrolysis temperature maximized the carbon concentration with reduced oxygen moieties (low O/C ratio), indicating a high energy value as the oxygenates were eliminated during moderate pyrolysis. The RDF treated at 400 °C (SF4-400) with MSW composition of 55% non-biogenic carbon and 45% biogenic carbon resulted in HHV of 29.22 MJ kg−1, the lowest ash concentration (0.96%), and a densified microstructural surface. The addition of natural maize cob additive into MSW (SF4-400-MC) yielded the maximum HHV (33.07 MJ kg−1) with considerable reductions in chlorides (71.43%), sulphides (87.50%), and insignificant nitrides content, all of which meet ASTM RDF quality criteria Grade I. [ABSTRACT FROM AUTHOR]

The study assessed quality of briquettes produced from bagasse (B), corn husk (CH), and cassava roots (CR) using banana peels (BP), wastepaper (WP), and clay soil (CS) as binders. Mixing ratios were established from carbonized materials, and briquettes physical and combustion properties were determined. Weak shatter resistance appeared in WP, CS briquettes had best tumbling resistances while WP briquettes had better water penetration. CS briquettes (3:1:1) had low (2.7%) moisture content (MC), and 1:3:1 had low (28%) volatile matter (VM) while the highest was 41% for 2:2:1. Ash content (AC) for 2:2:1 was the highest (41%) with highest heating value (HV). BP briquettes for 0:4:1 (CH:CR:BP) had the lowest MC (4.9%), whereas 2:2:1 (B:CH:BP) had the highest VM (41.5%). AC (15.5%) for 1:3:1 was the highest while 2:2:1 (CH:CR) had the highest HV. WP briquettes 1:3:1 (B:CH) had the lowest MC (2%) and 3:1:1 had highest VM (35%), while the highest AC appeared for 4:0:1. The 2:2:1 (B:CR:WP) briquette yielded the highest HV (25.5 MJ/Kg). All materials were suitable for briquetting, although their qualities are sensitive to weather conditions. Together with BP briquettes, WP briquettes 2:2:1 (B:CR:WP) produce the best results, especially when using CR and CH feedstocks. [ABSTRACT FROM AUTHOR]

This article presents the results of the study of the morphological composition of municipal solid waste (MSW) from the landfill of Atyrau city, and the waste's energy characteristics and presence of microorganisms, including bacteria, fungi and viruses. This study was carried out under a government order to determine the feasibility of recycling accumulated and incoming waste into electricity and its hazard to the environment and the workers involved in handling it. At the moment, there is no MSW recycling in Kazakhstan, which has led to the accumulation of more than 125 million tons of waste with an annual increase of 5 million tons. The research included four major cities (Almaty, Shymkent, Atyrau and Astana), which were selected not only on the basis of population, but also because the cities were located in different climatic zones. Samples were collected at the city landfills: 10 samples with an average distance of 100 m from each other were collected to provide a maximum coverage of both recently received waste and long-time stored waste. The research showed that neither climatic conditions nor the population size had a significant impact on MSW density, the values of which ranged from 120.1 kg/m3 to 145.4 kg/m3, as this indicator directly depends on the quality of life. The mass of the combustible fraction ranged from 39.41% to 54.62% and was mainly represented by plastic, textile and paper waste. The average value for the four cities was 50.30%. The higher calorific value fell in the range of 24.22–30.49 MJ/kg, with an average value of 26.71 MJ/kg. Microbiological studies showed little difference in average composition regardless of climatic conditions. Thus, no sharp differences in MSW composition, its energy characteristics and microbiological composition were found. The results of this study may be useful for optimising MSW recycling and disposal processes, as well as for developing measures to reduce their negative impact on the environment and human health. [ABSTRACT FROM AUTHOR]

The main part of companies in Bulgaria are built, however in the 70s, and upgraded last decade. The country supplies around 80 % of its supplies of paper, paperboard and pulp with own production. Integrated treatment of wastes is a priority for realizing closed life cycle of materials. The aim of the present work is to investigate the composition and other important characteristics of biomass wood ash wasted from paper industry. The correlations and associations among the chemical characteristics are also studied to find some basic trends and important relationships between two similar wastes from different enterprises. It was proved that all samples taken contained Ba, Cr, Mn, Ni, Co, Al, Fe, Cu and Zn far below the legal limits for such type of products. A product has a certain anti-acidic effect. The other positive result was that the content of iron is between 34 to 60 mg per 1 kg dry waste. The microscopic photos confirmed that the particles are close to the nano-size materials. The content of the elements C, N, H is in good quantities and ratios, which is a prerequisite for their use as a soil improver. By the results of this study, it was confirmed that all samples produced as a result of the thermal treatment and final low water content achieved are free from pathogen microorganisms and different weed seeds, affecting the yield and soil sustainability. That allows determining the optimal ratio between the used components with a view to obtain products with desired thermal stability and physico-chemical properties as soil improvers. [ABSTRACT FROM AUTHOR]

This paper reports an innovative study that aims to address key issues in the efficient recycling of wastepaper cellulose. The research team utilized the temperature-responsive upper critical solution temperature (UCST) polymer P(NAGA-b-DMA) in combination with the LytA label's affinity for choline analogs. This innovative approach enabled them to successfully develop a novel soluble immobilized enzyme, P(NAGA-b-DMA)-cellulase. This new enzyme has proven highly effective, significantly enhancing the degradation of wastepaper cellulose while demonstrating exceptional stability. Compared with the traditional insoluble immobilized cellulase, the enzyme showed a significant improvement in the pH, temperature stability, recycling ability, and storage stability. A kinetic parameter calculation showed that the enzymatic effectiveness of the soluble immobilized enzyme was much better than that of the traditional insoluble immobilized cellulase. After the immobilization reaction, the Michaelis constant of the immobilized enzyme was only increased by 11.5%. In the actual wastepaper degradation experiment, the immobilized enzyme was effectively used, and it was found that the degradation efficiency of wastepaper cellulose reached 80% of that observed in laboratory conditions. This novel, thermosensitive soluble immobilized cellulase can efficiently catalyze the conversion of wastepaper cellulose into glucose under suitable conditions, so as to further ferment into environmentally friendly biofuel ethanol, which provides a solution to solve the shortage of raw materials and environmental protection problems in the paper products industry. [ABSTRACT FROM AUTHOR]

Selective enrichment of La(III) by green material as an industrial raw material is of great research interest. In this study, the selective interaction between P and La(III) was utilized, and waste paper (WP) modified with phytic acid (PA) was used to adsorb La(III) from water using a simple one-pot method. The adsorption capacity was 237.23 mg g−1 (30 °C, pH = 5, initial concentration of 200 mg L−1). The equilibrium isotherm fitted the Langmuir isotherm model well. The adsorption equilibrium was reached after 15 min. The adsorption kinetics followed the pseudo-second-order kinetic model, indicating that the adsorption mechanism of the material towards La(III) is single-layer chemisorption. It selectively adsorbed La(III) from four coexisting substances (Pb, Ni, Cu, and Co). After six cycles, the adsorption efficiency of the adsorbent material remained at 60%. [ABSTRACT FROM AUTHOR]

Geopolymer concrete has been developed as a means of reducing carbon dioxide (CO2) emissions due to concrete manufacturing, which account for around 5-10% of the total global CO2 emissions. Additionally, this innovative material aims to utilize industrial waste as a sustainable resource. This study concentrates on developing a geopolymer mortar composition comprising 70% fly ash and 30% metakaolin. The mixture also includes 14 molars of sodium hydroxide, sodium silicate, saturated surface dry sand, water at a volume of 10% of the mix, and 1.5% superplasticizer. The solution-to-solid materials ratio was established at 0.55 while the ratio between sodium silicate and sodium hydroxide was established at 2.5:1. The geopolymer mortar was enhanced by rice husk fibers at varying volume percentages of 1%, 1.5%, and 2%. Additionally, waste paper, in the form of paper ash, was introduced as filler at a volume percentage of 5%. Following the demolding process, the specimens were cured in the controlled environment of an oven, with the temperature set at 60 °C for a period of 24 hr. Subsequently, the cured samples were stored for 7 and 28 days and then were tested. When different amounts of rice husk fibers were mixed in with a fixed amount of 5% paper ash, the flexural resistance of the geopolymer mortar increased significantly. After 7 days of curing, it was seen that the flexural strength experienced an increase of 4%, 13%, and 25%, and a further increase of 11%, 18%, and 31% after 28 days of curing. The results of the impact test showed a notable enhancement in impact resistance and energy absorption when incorporating paper ash and rice husk fibers. Specifically, the initial crack results exhibited a 50% rise, while the specimen failure after 28 days of curing showed a 66% improvement. [ABSTRACT FROM AUTHOR]

This study assesses the mechanical properties of mortars incorporating waste paper sludge-derived cellulose fibers. Compression and flexural tests were carried out on specimens prepared with cellulose fibers at different proportions, ranging from 0% to 2% of the total weight of the solid mortar constituents (cement, sand, and lime). In addition, a comparative analysis was carried out to evaluate the influence of the preparation method on the mechanical properties of the mortars. To this end, two series of mortars were studied: one prepared following a rigorous control of the preparation parameters and the other made without systematic parameter control to simulate typical on-site conditions. Finally, the applicability of both traditional and eco-friendly mortars in the construction of small-scale masonry walls was assessed through compression tests. Overall, the mechanical properties of mortars with cellulose fibers were comparable to those with 0% waste material, regardless of the production process. Regarding the compressive behavior of masonry walls, experimental tests showed significant similarities between specimens made with traditional and eco-friendly mortar. In conclusion, incorporating cellulose fibers into cement-based mortar shows considerable potential for building applications, enhancing the environmental benefits without compromising the mechanical behavior. [ABSTRACT FROM AUTHOR]

Socio-ecological theories have long been in search of general principles to characterise anthropogenic activity-environmental change dynamics. Besides allowing for more flexible hypothesis testing, stochastic-extended IPAT and ImPACT baselines opened the door to multiple environmental applications in which solid waste generation took a growing stage. This paper surveys Waste Kuznets Curve's original foundations and underlines why the nature and shape of the hypothetical curvilinear income-waste response function tend to compare to a "black-box". It then stresses why diverging conclusions are linked to heterogeneous estimators' choices differing in their statistical assumptions and powers; whereas generic patterns hardly emerge (e.g., income elasticities of waste generation vary even when the mathematical functional form does not; population elasticities are sensitive to time-varying data and income groups). Next, we identify persisting biases of endogeneity which threaten the internal validity of WKC conclusions, if uncontrolled for (e.g., simultaneity, waste measurement errors and garbage policy confounding effect); along with other identification problems including within-panel heterogeneity with systematic slope variations and cross-sectional and spatially dependent income series. Although we propose a set of theoretically justified instrumental variables to exogenously predict income levels and ensure unbiased elasticities, we also detect and underline that additional threats to external invalidity do play out in practice (e.g., asymmetric geographical coverage and bias of case study selection due to environmental data constraints; missing policy-realm; within-waste heterogeneity hidden by widely aggregated indicators; and a non-systematic treatment of the technological effect). All prevent the waste literature from converging and should be considered by future empirical assessments. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass holds promise as a renewable feedstock for various applications, but its efficient conversion requires cost-effective degradation strategies. The main objective of this study was to investigate the effect of the growth conditions of Cellulomonas phragmiteti in the production of (hemi)cellulosic supernatants. To meet this aim, different lignocellulosic residues were used as carbon sources for growth using defined mineral or nutritive culture media. Cell-free culture supernatants with xylanolytic activity were produced in all the conditions evaluated, but the highest xylanase activity (15.3 U/mL) was achieved in Luria–Bertani (LB) medium containing 1% waste paper. Under these conditions, almost negligible β-glucosidase, cellobiohydrolase, β-xylosidase, and α-arabinofuranosidase activity was detected. The xylanolytic supernatant showed tolerance to salt and displayed maximal catalytic efficiency at pH 6 and 45 °C, along with good activity in the ranges of 45–55 °C and pH 5–8. As it showed good stability at 45 °C, the supernatant was employed for the hydrolysis of birchwood xylan (50 g/L) under optimal conditions, releasing 10.7 g/L xylose in 72 h. Thus, C. phragmiteti was found to produce a xylanolytic enzymatic supernatant efficiently by utilizing the cheap and abundant lignocellulosic residue of waste paper, and the produced supernatant has promising attributes for industrial applications. [ABSTRACT FROM AUTHOR]

Pyrolysis of medical waste components combined via a novel systematic combination approach (sequentially binary, ternary, and quaternary copyrolysis) was conducted at 400°C to investigate the synergy between medical waste components in improving chemical characteristics and yields of pyrolytic oil. Pyrolysis of hydrocarbon-polymer-containing materials such as medical gloves and rubber bands produced more than 30% of liquid products with substantial compositions of saturated aliphatic hydrocarbon polymers. On the other hand, moisture- and carbonyl-rich pyrolytic liquid products with low selectivity were obtained from pyrolysis of lignocellulosic biomass waste such as HVS paper (houtvrij schrijfpapier, meaning "writing paper made from wood pulp") and garden waste. Binary copyrolysis of lignocellulosic biomass and medical gloves exhibited improvement on pyrolytic liquid yield and selectivity toward saturated aliphatic hydrocarbon polymers due to hydrogen donor as the medical glove fraction became dominant. The addition of rubber band to the mixture of HVS paper and medical face masks enhanced the pyrolytic liquid yield. The pyrolysis of the mixture of HVS paper, medical face masks, medical gloves, and either rubber bands or cotton fabrics with mixture ratio of 60:20:10:10 yielded the most optimum pyrolytic liquid yield with significant distribution of alkanes in the pyrolytic liquid products. [ABSTRACT FROM AUTHOR]

The growing demand for environmentally friendly and sustainable materials has led to the invention of innovative solutions aiming to reduce negative impacts on the environment. Mycelium-based green composites (MBCs) have become an alternative to traditional materials due to their biodegradability and various potential uses. Although MBCs are accepted as modern materials, there are concerns related to some of their physical and mechanical properties that might have limitations when they are used. This study investigates the effects of using paper waste to improve MBC properties. In this study, we investigated the physical and mechanical properties of MBCs produced from lignocellulosic materials (corn husk and sawdust) and mushroom mycelia of the genus Lentinus sajor-caju TBRC 6266, with varying amounts of paper waste added. Adding paper waste increases the density of MBCs. Incorporating 20% paper waste into corn husks led to the enhancement of the compression, bending, and impact strength of MBCs by over 20%. Additionally, it was also found that the MBCs produced from corn husk and 10% paper waste could help in reducing the amount of water absorbed into the material. Adding paper waste to sawdust did not improve MBC properties. At the same time, some properties of MBCs, such as low tensile strength and high shrinkage, might need to be further improved in the future to unlock their full potential, for which there are many interesting approaches. Moreover, the research findings presented in this publication provide a wealth of insightful information on the possibility of using paper waste to improve MBC performance and expand their suitability for a range of applications in sustainable packaging materials and various home decorative items. This innovative approach not only promotes the efficient utilization of lignocellulosic biomass but also contributes to the development of environmentally friendly and biodegradable alternatives to traditional materials. [ABSTRACT FROM AUTHOR]

Thiophene sulfide is difficult to be removed by hydrodesulfurization. In this study, ZnCl2-waste paper fiber activated carbon was used as adsorbent to remove thiophene sulfide from simulated oil by hydrothermal modification. Under the optimum condition of ammonia modification, the adsorption capacity of modified adsorbent to BT is 14.8 mg S/g, 2.98 times that of unmodified. BET, FTIR and Boehm analysis showed that the mesopore volume of ammonia modified adsorbent increased by 96.62% and the mesopore ratio increased from 12.58% to 43.40%, which was conducive to improving the adsorption rate. After modification, the basic groups on the surface of the adsorbent increased by 44.3 times, and –NH3+, –OH and –NH2 enhanced the electron attraction and hydrogen bonding force between the adsorbent and BT molecule. Adsorption isotherms, adsorption kinetics and adsorption thermodynamics show that the adsorption process is spontaneous, entropic and exothermic. The pseudo-second-order kinetic rate constant increases with the increase of adsorption temperature, indicating that the increase of temperature is beneficial to accelerate the adsorption rate. The adsorption desulfurization process follows the mechanism of single and multilayer adsorption mixing. The results of this study can help to reveal more clearly that biobased activated carbon can be modified to adsorb thiophene sulfide. Ammonia modified adsorbents enhance the adsorption capacity for benzothiophene [ABSTRACT FROM AUTHOR]

Complex polymers represent a challenge for remediating environmental pollution and an opportunity for microbial‐catalysed conversion to generate valorized chemicals. Members of the genus Streptomyces are of interest because of their potential use in biotechnological applications. Their versatility makes them excellent sources of biocatalysts for environmentally responsible bioconversion, as they have a broad substrate range and are active over a wide range of pH and temperature. Most Streptomyces studies have focused on the isolation of strains, recombinant work and enzyme characterization for evaluating their potential for biotechnological application. This review discusses reports of Streptomyces‐based technologies for use in the textile and pulp‐milling industry and describes the challenges and recent advances aimed at achieving better biodegradation methods featuring these microbial catalysts. The principal points to be discussed are (1) Streptomyces' enzymes for use in dye decolorization and lignocellulosic biodegradation, (2) biotechnological processes for textile and pulp and paper waste treatment and (3) challenges and advances for textile and pulp and paper effluent treatment. [ABSTRACT FROM AUTHOR]

As the construction of high-rise buildings increases to solve residential spaces caused by high density population concentration, the occurrence of fire accidents in high-rise buildings is also increasing. The primary cause of fire damage in high-rise buildings is the spread of fire caused by exterior wall finishes. Therefore, it is essential to develop semi-non-combustible finishes that can be applied to high-rise buildings to prevent the spread of fire due to exterior wall finishes. To address this issue, numerous studies are being conducted to develop flame retardant finishing materials that reduce heat release rate and total heat release. A double flame retardant mixed waste paper with expandable graphite and magnesium hydroxide was manufactured to improve the fire performance of cellulose building finishing materials. Total heat release (THR), CO, and CO2 Generation changes were measured using a cone calorimeter, and thermal diffusion rate was measured through the LFA 1000 experiment. The correlation of total heat release, CO generation, CO2 generation, and mass reduction rate by variation of expandable graphite's mesh size at double flame-retardant waste paper were secured through a cone calorimeter test. The thermal diffusion rate data of the specimen were secured through the LFA 1000 experiment. Through experiments, it has been confirmed that specimens using specific expandable graphite particles can be utilized as fire-resistant finishing materials in construction, ensuring fire resistance performance. [ABSTRACT FROM AUTHOR]

Microbial-induced calcite precipitation (MICP) is an innovative technology in civil engineering. However, the high cost of components and the fragility of the treated soil limit its wide use. One of the possible solutions is organic waste incorporation at different stages of the technology. In the present study, we consider the use of spent brewer's yeast (BSY) to produce bacterial inoculates and wastepaper, flax shives and sawdust as reinforcing additives into the soil. We showed that the replacement of expensive components of LB medium by BSY extract increased biomass growth characteristics of Bacillus subtilis K51, B. cereus 4b and Micrococcus luteus 6 strains by 1.4, 1.5 and 1.8 times, respectively, while for B. subtilis 168, they were comparable to LB medium. The urease activities of all strains were not reduced compared to the control. Among the three kinds of cellulose-containing waste, wastepaper incorporation into MICP-treated soil samples led to an increase in compressive strength by 2.1 times and precipitated calcite percentage by almost 1.5 times compared to a sample without additives. Thus, we showed the potential for soil stabilization through MICP using organic waste. [ABSTRACT FROM AUTHOR]

Less than 65% of wastepaper can be recycled, and the remaining wastepaper may end up polluting groundwater and generating greenhouse gas emissions if disposed improperly by using traditional approaches. The concept of circular supply chain practices, which integrates circular thinking into supply chain practices that aim to reach zero waste by exploring novel business models and supply chain functions, has been proposed to address this issue. However, previous studies implementing this concept lacked appropriate methods for structuring an influential model to guide resource allocation, which caused difficulty in developing circular supply chain practices. Thus, a hybrid method is proposed to integrate factor analysis with fuzzy synthetic and decision-making and trial evaluation laboratory methods to enable visual analysis and boost understanding. The results reveal that awareness and engagement are the most influential factors in attempts to achieve zero waste, rather than the recycling, reuse and reduction practices emphasised by previous studies. [ABSTRACT FROM AUTHOR]

Many stray animals throughout the world unfortunately do not get the opportunity to find the loving home that they deserve. In this classification task, we look to develop an algorithm to predict the speed of pet adoptions. The input to our algorithm includes animal type (dog or cat), breed, gender, colour, profile picture online and the descriptions about the pet, etc. We then use both traditional machine learning techniques (Logistic Regression, Naive Bayes, SVM, Decision Tree, Random Forest and Gradient Boosting) and neural networks (fully connected neural networks and long short-term memory Model) to predict the adoption rate. In particular, we build feature vectors using information extracted from description scripts and feed them into neural network models. We are hoping to examine the results to develop strategies to help improve the overall adoption rate (i.e. what features lead to faster adoption). Every year, 3.3 million canines visit animal shelters, out of a total population of 200 million. Only 2% to 17% of pets are returned to their owners. The remaining animals are euthanized due to a shortage of room in shelters (killed). The present procedures for adapting or finding a pet are inefficient and haphazard. People disseminated leaflets to the general public and spread the word to others in the vicinity of the pet's disappearance. When individuals print fliers, they waste paper and money since there is no good impact. People also share their tales on social media sites like Instagram and Facebook. There are also several fraudsters who attempt to fraudulently claim the incentive for returning the pet to its legitimate owner. We want to provide an analysis on how fast pets(cats and dogs) can be adopted based on various factors like their health conditions, age, colour, breed etc. [ABSTRACT FROM AUTHOR]

Mathematical modeling is a high-leverage topic; it is critical to students' participation in STEM education and supports civic engagement. Until recently, research on modeling at the elementary level has been underemphasized, particularly research on supports and challenges for teachers who engage in designing authentic modeling tasks. In this study, we employed qualitative case study methods to investigate how elementary teachers designed and implemented authentic mathematical modeling tasks, with an explicit focus on how their tasks evidenced different dimensions of authenticity. We analyzed three cases of teams of elementary teachers as they developed modeling tasks connected to school and community contexts. The three cases were: 1) a student-driven modeling task related to paper and plastic waste in a school cafeteria, 2) a modeling task based on authentic situations at a community-run resource center, and 3) a modeling task focused on designing and monitoring a school community-building art project. Our cases illustrate that elementary teachers can successfully design and implement modeling activities that utilize different entry points and evidence multiple dimensions of authenticity. Furthermore, we found that the specific dimensions of authenticity may vary depending on the design supports and curriculum challenges within each context. [ABSTRACT FROM AUTHOR]

This study evaluated the production of marine biodegradable plastics, specifically polyhydroxyalkanoates (PHAs), using waste paper from food containers as a novel material source. The results showed that adding dilute sulfuric acid as a pretreatment may have a negative impact on enzyme hydrolysis efficiency. Without pretreatment, the highest glucose concentration was observed in the 50-min heating group. In the experimental group with 1% dilute sulfuric acid as a pretreatment, the highest average glucose concentration was observed in the 25-min treatment group. In flask scale experiments, the C/N ratio was controlled at 10, 20, and 30. The results showed that when the C/N ratio was 10, the PHA/CDM ratios were 16.3 and 23.6 at 48 and 72 h, respectively. After 96 h of cultivation using hydrolysis liquid from the waste paper container as the sole carbon source in a 5-L scale experiment, the PHA/CDM ratio was 28.7 and the PHA concentration was 0.95 g/L. The potential bacterial strain in this study was confirmed to be a Bacillus genus bacterium after strain identification. The signal peaks indicated that the PHA obtained from the Bacillus sp. production process was PHB. [ABSTRACT FROM AUTHOR]

Halochromic azo dyes have versatile applications, including sensing and anti‐counterfeiting, due to their reversible color‐changing properties. In this work we investigated the structure‐dependent halochromism of azo compound (E)‐4‐((2‐hydroxynaphthalen‐1‐yl)diazenyl)benzenesulfonamide (HDBS) and explore its potential applications using experimental and theoretical approaches. Different spectroscopic techniques confirm the structural change in the dye as a consequence of tautomerism reaction upon changing pH (7 to 13). The stable form of hydrazone is isolated and characterized. Based on the spectroscopic characterization, it is concluded that the azo form exists at pH ≤ 9, whereas the hydrazone form at highly alkaline pH. To understand the origin of the absorption peaks, the stability, and tautomerism in water, DFT and TD‐DFT calculations are performed. A reasonable agreement between the theoretical and experimental observations enabled us to unravel the structure‐dependent halochromism. Further, we have shown that HDBS‐coated paper can be a real‐time visual sensor to monitor fish freshness and for anti‐counterfeiting ink. It changes colors with pH shifts, alerts consumers about the status of food. Additionally, erasable paper strip reduces paper waste and chemical pollution. The findings presented in this work provide a promising avenue for the development of halochromic azo compounds with potential applications in sensing and anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Municipal waste management is a major challenge for local governments in South Africa and Namibia, as in other developing countries. The circular economy concept in waste management is an alternative sustainable development framework that has the potential to combat resource depletion, pollution, and poverty while achieving the SDGs. The purpose of this study was to investigate the current waste management systems in Langebaan and Swakopmund municipalities resulting from municipal policies, procedures, and practices in the context of a circular economy. A mixed method approach was used to collect qualitative and quantitative data through structured in-depth interviews, document analyses, and direct observation. The study found that the Langebaan and Swakopmund municipalities have not yet fully implemented the circular economy concept into their waste management systems. A mix of waste consisting of papers, plastics, cans, tyres, and organic products is dumped into landfills weekly at a rate of about 85%. The main challenges to implementing the circular economy concept include: lack of technical solutions, inadequate regulatory frameworks, insufficient financial resources, lack of private sector involvement, insufficient human resource capacity, and inadequate information and knowledge. A conceptual framework was therefore proposed to guide the municipalities of Langebaan and Swakopmund in implementing the circular economy concept in their waste management systems. [ABSTRACT FROM AUTHOR]

This study focuses on the increased risk of high heat release and asphyxiation (toxic gas poisoning) in the event of a fire involving polyurethane (PU)- and MDF-based building materials, which are commonly used in buildings. Among them, polyurethane (PU) building materials are very commonly used in buildings, except in Europe and some other countries, due to their excellent thermal insulation performance. Still, problems of short-term heat release and the spread of toxic gases in the event of a fire continue to occur. To overcome these problems, researchers are actively working on introducing various flame retardants into building materials. Therefore, in this study, we produced a laboratory-sized (500 mm × 500 mm) plate-like flame-retardant board that can be utilized as a building material with a lower heat release rate and a lower toxicity index. The material was made by mixing expanded graphite and ceramic binder as flame retardants in a material that is formulated based on the cellulose of waste paper, replacing the existing building materials with a hot-press method. According to the ISO-5660-1 test on the heat release rate of the plate-like flame-retardant board, the Total Heat Release (THR) value was 2.9 (MJ/m2) for 10 min, showing an effect of reducing the THR value by 36.3 (MJ/m2) compared to the THR value of 39.2 (MJ/m2) of the specimen made using only paper. In addition, the toxicity index of the flame-retardant board was checked through the NES (Naval Engineering Standards)-713 test. As a result, the test specimen showed a toxicity index of 0.7, which is 2.4 lower than the toxicity index of 3.1 of MDF, which is utilized as a conventional building material. Based on the results of this study, the cellulose fire-retardant board showed the effect of reducing the heat release rate and toxicity index of building materials in a building fire, which reduces the risk of rapid heat spread and smoke toxicity. This has the potential to improve the evacuation time (A-SET) of evacuees in fires. It is also important to show that recycling waste paper and utilizing it as the main material for building materials can be an alternative in terms of sustainable development. [ABSTRACT FROM AUTHOR]

This research investigated an up-draft gasification system of paper waste sludge (PWS) to generate syngas. Lower heating value (LHV) and cold gas efficiency (CGE) are influenced by PWS moisture content and equivalence ratio (ER). Supply air for gasification by increasing ER reduced LHV due to increased inert gas (N2) content. PWS moisture provides steam for the water-gas shift reaction that increases LHV and CGE. But the moisture of the PWS higher than 15 % significantly reduced the gasification temperature (less than 800 °C), causing the overall gasification efficiency to decrease. According to the response surface methodology (RSM) using Design Expert software, the optimum conditions were predicted that PWS moisture of 11.09 %, ER of 0.104, syngas produced with an LHV of 10.48 MJ/kg, and a CGE of 67.55 %. Experimenting with a real model has similar results with small differences compared to the RSM model in the same conditions. Syngas from the real model has an LHV of 10.22 ± 0.24 MJ/kg and a CGE of 65.68 ± 1.02 %. PWS gasification under optimal conditions is an effective PWS treatment method that not only solves PWS but can also generate energy in the form of syngas. [ABSTRACT FROM AUTHOR]

This study investigates the sulfuric acid hydrolysis process to improve the efficiency of paper waste sludge (PWS) hydrolysis in a paper recycling plant. The Response Surface Methodology (RSM) was used to evaluate the influence of factors, including liquid-to-solid ratio, acid concentration, temperature, and time on the hydrolysis process. The optimal conditions for hydrolysis were determined to be a solid-to-liquid ratio of 1/30.15, an acid concentration of 8.17 wt%, at a temperature of 91.31 °C, and a reaction time of 6.15 h, which yielded the highest sugar content of 11.12 g.L-1 (with the hydrolysis efficiency of 61.4 %). The resulting sugar solution was then fermented by Acetobacter xylinum bacteria to produce bacterial cellulose (BC) layers. This study addresses the environmental organic pollution caused by PWS and transforms it into a more valuable form with high carbon content and purity, such as BC. [ABSTRACT FROM AUTHOR]

Samples of plastic and paper waste were collected and subjected to various procedures including drying, manual sorting, pulverization, and homogenization. The elemental analysis of the samples was conducted following the ASTM D3176-15 standard, revealing that the plastic-paper composite samples had lower carbon and hydrogen content compared to the PL100 plastic benchmark. While thermogravimetric tests were performed on the samples in a thermal analyzer according to the ASTM procedure. Interestingly, the composite samples showed a higher presence of elemental oxygen, except for the sample with 25%wt. of paper. Moreover, sulfur content increased in composite samples with 25% wt., 50% wt., and 75% wt. of paper, while the sample with 100% wt. of paper exhibited a decrease in sulfur content. Combustibility was assessed based on the peak temperature at the maximum weight loss rate, indicating that samples PL100, PL50+PA50, and PL75+PA25 displayed higher combustibility compared to samples PL25+PA95 and PA100. Hence, these samples could be recommended for use as refuse-derived fuel due to their potential for energy recovery. The impact of waste-to-fuel research will be felt in waste reduction (SDG 7), clean energy (SDG 12), climate action (SDG 13), and ecosystem protection (SDG 15). [ABSTRACT FROM AUTHOR]

Increased solid waste pollution and the negative effect of fossil fuel consumption on the environment are issues that would require more scientific attention and application to deal effectively with these phenomena. Wastepaper, a major component of solid waste, is classified as organic waste due to the presence of cellulose, a glucose-based biopolymer that is part of its structural composition. The saccharification of cellulose into glucose, a fermentable sugar, can be achieved with a hydrolytic enzyme known as cellulase. Although cellulase from fungal species such as Trichoderma, Aspergillus, and Penicillium are well described, knowledge about cellulase isolated from the brown garden snail is limited as it has not been the subject of many research endeavors. The waste paper has been described as a suitable resource for bio-energy development due to cellulose, a structural component of this bio-material that can be degraded into glucose, a fermentable sugar. Although paper materials such as newspaper, office paper, filter paper, Woolworths and Pick and Pay (retailers) advertising paper, as well as foolscap paper, were saccharified by different cellulases, the degradation of these paper materials by garden snail cellulase is a novel investigation from our laboratory. With the effects of temperature and incubation time on this cellulase action when degraded paper materials have already been investigated and reported, this study dealt with the garden snail cellulase action when degraded paper materials at different pH values. Most of the paper materials were degraded optimally at a pH value of 6.0, while optimum saccharification was observed at pH 4.5 when newspaper and brown envelope paper were degraded, with office paper showing maximum bioconversion at pH 7.0. The difference in the structural composition of the paper materials also affects the degree of saccharification, as the amount of sugar released from the various paper materials at optimum pH values is not similar. Together with other catalytic parameters, the pH value of this enzymatic catalysis is also to be considered when designing the development of waste paper as a bio-product resource, with limiting environmental pollution as an additional advantage of this process. [ABSTRACT FROM AUTHOR]

A comparative study of the supramolecular structure, physicochemical properties, and morphology of the powder celluloses (PCs) obtained from the waste paper of newsprint and cardboard, plant celluloses, and nonconventional raw materials was conducted using the methods of FT-IR spectroscopy, high-resolution solid-state 13C NMR spectroscopy, wide-angle X-ray scattering, and scanning electron microscopy (SEM). According to the FT-IR and 13C NMR spectroscopy results, the functional composition of the PCs is similar to that of the wood PCs and matches highly purified cellulose samples. The crystallographic structure of the powder samples corresponds to the structure of cellulose I. The crystallinity and the transverse dimensions of the crystallites are 39.4 and 40.2%, and 45 Å [110] and 54 Å [110], for the PCs from newsprint paper and cardboard, respectively. These values considerably exceed those for the initial waste paper samples. A comparative analysis of the SEM results showed a significant similarity among the PC fibers of different origin. The results of the study of the physicochemical properties of the PCs isolated from the waste paper allow predicting their competitive application in comparison with plant PCs. [ABSTRACT FROM AUTHOR]

This research explores the challenges and limitations faced at the basic level for the recycling of paper in an academic institute. It focuses on encouraging recycled paper use rather than bringing traditional virgin paper to prevent the rate of deforestation for reducing global warming. Data was collected from the academic institute via questionnaire and on-site observation and found that the institute was producing approximately 16 tons of wastepaper in a year. Besides that, another purpose of this research is to estimate the energy and assess the environmental effect by using the life cycle assessment as a tool. The results of this study revealed that traditional virgin paper derived from wood proves to be costly and less environmentally friendly than recycled paper. It also revealed that Traditional virgin paper has greater global warming, human toxicity, smog, acidification, and eutrophication potential than recycled paper. This study concludes that recycled paper does not only prove economically beneficent for any institution, but also beneficial for environment as well. [ABSTRACT FROM AUTHOR]

To ensure development sustainability, the linear economic approach is being transformed into a cyclical model. For the pulp and paper industry (PPI), which occupies a significant place in the Russian economy, the shift of circular principles to the field of bioeconomics is becoming more important. This requires the development of basic biotechnological approaches implemented in closed cycles (biorefining). The aim of this study was to develop the biotechnological foundations of the circular economic system of the pulp and paper industry. To achieve the goal, the factors for the implementation of the circular mechanism in the pulp and paper industry were established. The composition of pulp and paper waste was systematized, taking into account the places of their occurrence; the directions and forms of the biorefining of pulp and paper secondary renewable resources were determined; and the principal possibility of obtaining bioethanol, based on the whole complex of sugars from cellulose production wastes, is shown. A wide range of general scientific methods was involved (analysis, synthesis, classification, modeling, etc.). Statistical methods were used to process experimental results in the field of pulp and paper waste bioconversion. The biotechnologies involved included methods of destruction, detoxification, and conversion of useful resources into secondary raw materials and final products. From the standpoint of the environmental approach, there are serious efficiency imbalances in the pulp and paper industry, which justify the implementation of circular mechanisms for organizing economic systems. The overall efficiency is ensured by the use of renewable resources and obtaining environmental effects. Algorithms and parameters of green biotechnological regulations for pulp and paper industry waste recycling provide the possibility of microbiological production of a complex of products: biocomposites, bioplastics, medical products, fertilizers, feed additives, vitamin supplements, and bioenergy resources. A strategy for the efficient biochemical processing of pulp and paper waste into green ethanol was determined. The possibility of increasing the efficiency of alcoholic fermentation using various biocatalysts was experimentally confirmed. The technological features of this method, associated with the need for microaerobic fermentation modes, were determined. [ABSTRACT FROM AUTHOR]

Finding sustainable solutions to the increasing waste generation in Ghana has received a lot of attention in recent years. Through several waste-to-energy processes, the energy potential of municipal solid waste has recently witnessed significant technological advancements. The Renewable Energy Master Plan has projected the production of about 122 MWp from waste-to-energy installations by 2030 in Ghana. To help policymakers and engineers achieve national goals, this paper reviews the waste generation in Ghana estimated from 2010 to 2030 and the status of various bioenergy technologies in Ghana. This paper further estimates the energy recovery potential of municipal solid waste in Ghana under incineration, anaerobic digestion, and landfill gas recovery technologies. The review establishes that, by 2030, municipal solid waste generation will increase by 123% of the 2023 quantities and may produce 1484.25 MW of installed electricity capacity and 13,002.03 GWh per year, which would amount to nearly 59% of Ghana's 2030 renewable energy target. Additionally, it was determined that anaerobic digestion, incineration, and landfill gas recovery technologies, when properly developed, will add 105.33 MW, 301.4 MW, and 377.31 MW of installed electrical capacity, respectively, to Ghana's energy mix in 2028. [ABSTRACT FROM AUTHOR]