Waste Paper Research Articles

Effects of tissue additives on copy paper forming and properties

Laboratory tests were conducted in an effort to determine the effects on paper machine process attributes and the properties of paper made from recycled copy paper furnish upon the addition of chemical agents that are commonly used in the production of hygiene tissue products. Due to continuing growth in tissue and towel grades of paper, such agents are experiencing greater usage. Charge titration test results revealed that certain dry strength agents associated with tissue manufacturing have the potential to shift the balance of charge in papermaking furnish to less negative or even positive values. Creping adhesive was found to contribute to fine particle retention, especially when present at relatively high levels. Release aid and a polyacrylate dispersant had the opposite effect. Low addition levels of both a creping adhesive and a debonding agent surprisingly increased a wide range of strength attributes of paper handsheets in comparison to sheets prepared from unaltered recycled copy paper furnish. The debonding agent decreased paper strength at higher levels of addition. Such effects appear to depend not only on the expected effects of agents themselves, but also on how they affect the charge balance of the wet-end system.

Effects of carboxymethyl starch as a papermaking additive

Carboxymethyl starch (CMS) is a bio-based, anionic polymer that has potential as part of a dry-strength additive program for papermaking. Due to its negative charge, its effects can be expected to depend on its interactions with various cationic agents. In this work, the effects of CMS were observed following its sequential addition after one of three selected cationic strength agents at different dosage levels. In selected tests, the furnish was pretreated at the 1% level by a dispersant, sodium polyacrylate, which might represent a high level of anionic contaminants in a paper mill system. Laboratory tests were conducted to show the effects on dewatering, fine-particle retention, and flocculation. These tests were supplemented with measurements of charge demand, zeta potential, and handsheet properties. Sequential addition of cationic glyoxylated acrylamide copolymers (gPAM) and CMS were found to strongly promote dewatering. Two gPAM products and a poly(vinylamine) product in sequential addition with CMS were very effective for promoting fine-particle retention. These same sequential treatments of the stock contributed to moderate fiber flocculation, though severe flocculation was caused by further treatment of the furnish with colloidal silica. Handsheet strength results were mixed. In the default recycled copy paper furnish, the average breaking length for the sheets made with cationic additives followed by CMS was not greatly different from the blank condition. Superior strength resulted when the default furnish was treated with a dispersant alone. When the dispersant-contaminated furnish was treated with the same combinations of cationic additives and CMS, the strength returned to the baseline achieved in the absence of the dispersant. The results were discussed in terms of the charged character of the different additives and their interactions not only with the fiber surfaces but also with each other.

From Waste Paper to Cellulose: Building Environmental Awareness by Chemical Technology from Pragmatistic Pedagogy

From Waste Paper to Cellulose: Building Environmental Awareness by Chemical Technology from Pragmatistic Pedagogy

Utilization of Paper Waste and Dried Leaves as Ceiling Board

Utilization of Paper Waste and Dried Leaves as Ceiling Board

Upcycling municipal solid wastes to self-foaming glass-ceramics by chemical additive-free and rapid low-temperature sintering

Incinerated sewage sludge ash (ISSA) and waste glass (WG) produced in large quantities from municipal solid wastes are either not recycled or are used in relatively low-value applications. Here, we reported a scalable strategy to rapidly convert them, along with waste paper (WP), into novel foamed glass-ceramics (FGCs) by low-temperature sintering, considerably reducing environmental impact and manufacturing cost. The Fe2O3 in ISSA and cellulose in WP were used as precursors to trigger the self-foaming process at low temperatures by carbon-enhanced ferric reduction when WG formed the softened matrix without chemical additives. This study analyzed the foaming mechanism, physical properties of FGCs, and variable importance assisted by thermodynamics and machine learning. The resulting FGCs with 20 wt% ISSA content and 10 wt% WP addition exhibited the excellent properties of a geometric density of 0.76 ± 0.02 g/cm3, volume water absorption of 14.35 ± 2.48%, and compressive strengths of 7.15 ± 0.88 MPa by a short holding (5 min) at a low firing temperature of 850 °C. The successful synthesis and mechanistic study provide new insights into the development of waste-derived high-performance FGCs.

A Comparative Benefit-cost Analysis for the Potential Waste Management Options for the Western Province, Sri Lanka

Sri Lanka generates 7,000 metric tons of solid waste per day while only 3,242 tons are being collected. Within the Western province 1783 metric tons are collected daily. Management of municipal solid waste is mainly a responsibility of local governmental entities. Only a few waste management options are often practiced while economic aspects of this problem are rarely taken into consideration. The present study was designed therefore with the objective of analysing current and potential waste management options for the western province and identifying the best option that maximises the net benefit to the country. Seven different options for municipal solid waste management were identified for the analysis (option 1–open dumping; 2-sanitary landfilling; 3- recycling paper, polythene, glass and other recyclable waste (15%) and open dumping the rest; 4- composting the biodegradable (62%) and open dumping the rest (38%); 5-composting the biodegradable (62%), recycling paper, polythene, glass and other recyclable waste (15%) and open dumping the remaining; 6–waste to energy handled by the government; 7–waste to energy collaborated with private organizations). Then costs and benefits, including environmental costs related to each option were identified and quantified using literature and information obtained from interviews held with coordinators of waste management projects under both government and private sectors. Economic cost-benefit analyses were conducted for the seven options for a period of 30 years assuming that a constant amount of municipal solid waste (100 MT) per day is treated by each method. All seven models were developed on the basis of current municipal solid waste composition. According to the net present value analysis, five options resulted in negative net present values, while options four and five showed positive net present values. In the next step, the value of compost was re-estimated considering the replacement benefit of imported nitrogen, phosphorus and potassium fertilizer which has yielded a much higher net present value than earlier. Furthermore, option five was identified as the economically most profitable option. The results of the study will provide guidance toward designing the most economically and environmentally viable waste management options for urban areas of Sri Lanka. 
 Keywords: Municipal solid waste, Composting, Recycling, Cost-benefit analysis

Characterization of Thermostable Cellulase Enzyme Isolated from a Hot Spring Bacterium: Bacillus sp.

Cellulase is a complex of enzymes which consists of β-1,4-endoglucanase, cellobiohydrolase, and β-glucosidase. Cellulase contributes a significant share to the world enzyme market and is used in number of industries viz; paper and pulp, food and beverage, bioethanol, detergent and textile. The harsh industrial conditions such as high temperature, extreme pH levels and high substrate concentration etc. which is used in such industries adversely effect on structure and activity of enzymes. Therefore, huge amount of chemical catalysts which cause chemical wastes are used in industrial settings instead of enzymes. Since the chemical wastes adversely affect the ecosystem, isolation and characterization of thermostable cellulase enzyme-producing bacteria and exploring the industrial perspective of thermostable enzymes is a better approach towards green chemistry. The present study focused on characterization of cellulase enzyme produced by Bacillus sp., which shows optimum activity at 60 C under neutral conditions, isolated from Gomarankadavala hot spring in Sri Lanka. The effect of different Carbon sources: glucose and lactose, Nitrogen sources: peptone, tryptone, yeast extract and urea on enzyme production and different Carboxymethylcellulose (CMC) concentrations; 0.5%, 1.5% and 2%, on enzyme activity were measured using the DNS method. Under the optimum conditions, cellulase enzyme activity on different substrates: corn cob, rice bran and raw leaves were measured. The highest enzyme production was recorded in the culture medium which added tryptone as the nitrogen source and adding carbon sources to the culture medium showed an increase of cellulase enzyme production. The optimum CMC concentration for the enzyme activity was recorded as 1% and from all the optimized parameters, the substrate; raw leaves showed the highest enzyme activity of 11.305 U/ml. Further, a considerable amount of enzyme activity was recorded on corn cobs and rice bran as well. Thus, the thermostable cellulase enzyme produced by bacterium identified as Bacillus cereus isolated from Gomarankadavala hot spring could be successfully used in industrial settings such as kitchen/industrial waste management, bioethanol production, paper and pulp industry and textile industry which use high temperatures and cellulosic substrates as raw materials. 
 Keywords: Thermostable enzymes, Cellulase, Industrial applications, Hot springs

Assessing the Ecological Cost of Material Flow in China’s Waste Paper Recycling System

This article introduces the concept of ecological costs associated with the waste paper recycling system. The costs associated with this process include resource consumption, waste emissions, ecological damage, and production processes. To analyze the ecological costs of deviations from the baseline material flow in a waste paper recycling system, a benchmark material flow diagram is constructed using the material flow analysis method. The diagram illustrates a fully closed one-way material flow of the recycling system, which is highly abstracted and simplified. The study analyzed the ecological costs of the benchmark material flow and the impact of deviations from it. The results suggest that the circulation of materials within and between processes increases the ecological cost of the waste paper recycling system. Furthermore, the release of materials from a process into the environment also contributes to its ecological impact. However, the introduction of external materials into the recycling system can reduce its ecological impact, particularly if these materials are recycled resources. The study emphasizes the significance of considering ecological costs in waste paper recycling systems to minimize their environmental impact.

Valorization of waste paper sludge as a sustainable source for packaging applications

Paper sludge consists mainly of wet short cellulose fibers that are lost during papermaking and of residual chemicals used in the manufacturing process that remain dissolved in the water. Each ton of paper generates about 40–50 kg of dry sludge, of which 70% is primary sludge. Paper production, which exceeded 400 million tons globally in 2020, generates vast volumes of solid waste. Primary sludge is usually fiber-rich and hence suitable to be recycled back into the papermaking process. However, if the sludge is to be disposed of in landfills, sustainable practices must be developed in order to recover the fibers as they are valuable source for manufacturing high value-added products. This study investigates the valorization of paper sludge discarded by a filter paper manufacturer, with the purpose of producing cellulose acetate films for food packaging. The process involves recovering cellulose fibers from the sludge, purifying them and through acetylation reaction produce cellulose acetate films. FTIR spectra confirmed successful acetylation of fibers and also that acetyl groups reduced the hydrophilicity of cellulose—the contact angle was increased to over 80° from 50° in native cellulose. The films exhibited very good water barrier properties at both 50% and 90% relative humidity (RH).Graphical abstract

The Effect of the Utilization of Sustainable Materials on Some Mechanical Properties of Geopolymer Mortar

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.

Co-pyrolysis of waste paper and tyre: Exploration of interaction of volatiles of varied origin and the influence on product evolution

Waste paper and tyre are typical solid wastes with distinct composition. Their pyrolysis could generate varied volatiles that may interact with each other or with resulting char. In this study, the co-pyrolysis of waste paper and tyre was investigated at 400 and 600 ºC, with the focus on understanding the interaction of the volatiles on evolution of the products. The results show that the interaction of the volatiles at 400 ºC forms more gaseous products like CO and CO2, while the interactions of the heavier organics at 600 ºC forms more oil (49.3% vs 42.6%). The interaction of the volatiles also affects the generation of sulfur-containing organics and diminishes the paper-derived aldehydes and ketones or the heavy organics with the π-conjugated structures in the oil. In addition, the volatile-char interactions exist and form the char of higher carbon content through promoting carbonization and deoxygenation reactions, generating char of higher thermal stability and higher hydrophilicity via tailoring functional group, pore structures and morphologies of the char.

A sustainable packaging composite of waste paper and poly(butylene succinate-co-lactate) with high biodegradability

The challenge of global climate change has drawn people's attention to the issue of carbon emissions. Reducing the use of petroleum-derived materials and increasing the use of biodegradable materials is a current focus of research, especially in the packaging materials industry. This study focused on the use of environmentally friendly plastics and waste paper as the main materials for packaging films. Poly(butylene succinate-co-lactate) (PBSL) was modified with maleic anhydride (MA) to form a biobased compatibilizer (MPBSL), which was then blended with a mixture (WPS) of waste-paper powder (WP) and silica aerogel powder (SP) to form the designed composite (MPBSL/WPS). The modification of PBSL with MA improved interfacial adhesion between PBSL and WPS. The structure, thermal, and mechanical properties, water vapor/oxygen barrier, toxicity, freshness, and biodegradability of MPBSL/WPS films were evaluated. Compared with the PBSL/WP film, the MPBSL/WPS film exhibited increased tensile strength at break of 4–13.5 MPa, increased initial decomposition loss at 5 wt% of 14–35 °C, and decreased water/oxygen permeabilities of 18–105 cm3/m2·d·Pa. In the water absorption test, the MPBSL/WPS film displayed about 2–6 % lower water absorption than that of the PBSL/WP film. In the cytocompatibility test, both MPBSL/WPS and PBSL/WP membrane were nontoxic. In addition, compared with PBSL/WP film and the control, the MPBSL/WPS film significantly reduced moisture loss, extended the shelf life, and prevented microbial growth in vegetable and meat preservation tests. Both MPBSL/WPS and PBSL/WP films were biodegradable in a 60-day soil biodegradation test; the degradation rate was 50 % when the WP or WPS content was 40 wt%. Our findings indicate that the composites would be suitable for environmentally sustainable packaging materials.

Eco-friendly Noise-absorbing Panels from Waste Materials: A Sustainable Solution to Control Noise Pollution

This research article deals with one of the major forms of pollution that is invisible but is a threat to living beings. Controlling noise pollution is important so to deal with this, a test was performed using a method known as the impedance tube method. To tackle this noise pollution a sustainable material would be good to use, so waste coming from food industries such as orange peel, sugarcane husk, and eggshells are used with newspaper sludge as a binding material. Disks were prepared of 90mm with different constituents of waste material and paper sludge. The test result showed that these panels were able to reduce sound coming from the source to the receiver side. Sound absorption capacity is different for every material depending upon their structural features. The test was done with 120 decibels of sound and at 120 decibels the SAC (sound absorption coefficient) was 0.35 which is better than other commercially available chemical-infused materials such as glass wool, mineral wool etc. As they are not better for the environment as well as living around. They cause lung disease if inhaled and skin problems come in contact with them. Materials in use for soundproofing have polyurethane which releases a high amount of smoke if brunt hence we cannot rely on this in case of fire. Hence environmentally friendly as well as materials that do not catch fire or realise high amounts of smoke and are also cost-effective should be used to reduce noise pollution in the environment we are living in.

Lessons from Paper Recycling for Single-Use Plastic Replacements

Lessons from Paper Recycling for Single-Use Plastic Replacements

Utilization of waste paper as teaching media for volcano eruption simulation in improving student knowledge

Indonesia has the highest number of active volcanoes in the world due to its geologic location at the confluence of the Eurasian and Australian plates. However, despite this, the knowledge of local communities regarding volcanic eruptions is still very minimal. Therefore, it is important to provide education to the community in this context is the local community. This Community Service Program aims to increase community knowledge related to the process of volcanic eruption by using pulp-based learning media, so that it can become disaster mitigation knowledge. The methods used are observation, coaching or training based on practical simulations, questionnaires and interviews. The subject of this Community Service is the community of Tambun village, Baolan sub-district, Tolitoli district, totaling 21 people in collaboration with students of the elementary school teacher education program in semester III. The results of this program are the increase in community knowledge related to volcanic eruptions and the growth of community awareness related to the use of waste paper, this is in line with SDGs 4 and SDGs 17 relating to quality education and partnerships with the community.

Waste‐Valorized Nanowebs for Crystal Violet Removal from Water

Lightweight, metal‐free, sustainable, and reusable adsorbent materials are of paramount significance in addressing the challenges of wastewater treatment. Accordingly, semi‐crystalline nanocellulose (NC) is extracted from tissue paper waste and used to modify polyacrylonitrile (PAN) to produce electrospun nanowebs with strand diameters from ≈180–300 nm. The incorporation of NC into PAN is confirmed by infrared and Raman spectroscopy and X‐Ray diffraction. When tested for crystal violet (CV) adsorption, NC‐modified PAN (20% NC@PAN) exhibits the highest CV removal capacity, achieving 91–94% removal over three cycles each, demonstrating exceptional recyclability. In contrast, unmodified PAN significantly decreases in CV adsorption capacity (from 59% to 48% in the third cycle), possibly due to an increased (≈36%) nanofiber diameter. The adsorption kinetics, exhibiting pseudo‐second order, interparticle (in between nanofibers) diffusion, and Elovich kinetic models emphasize the role of multilayer CV adsorption through reversible chemical interactions. Confocal micro‐Raman spectroscopy unveils a multifaceted CV adsorption mechanism, suggesting both surface and multilayer diffusion, with NC‐enhancing interactions. These findings demonstrate the potential of NC‐modified PAN nanowebs as effective and environmentally sustainable adsorbents for removing CV from aqueous solutions, suggesting promising practical applications.

Vermicompost from Kitchen Waste and Paper Waste by Eudrilus eugeniae, Nutrient Analysis and Efficiency on Alternanthera sessilis Plant Growth

In India, a significant amount of paper and kitchen waste is produced, much of which is either burned, left outside, or landfilled, creating a significant challenge for its safe disposal. The Eudrilus eugeniae (Kinberg) earthworms can be used to convert all kitchen and paper waste into extremely useful, nutrient-rich vermicompost. The vermicompost contributes significantly to the growth and yield of various field crops, vegetables, flower and fruit crops. The use of organic residuals lowers production costs while eliminating the requirement for waste disposal and incineration. The present research was carried out to find out the potential vermicompost using kitchen and paper waste to compost on the Eudrilus eugeniae earthworm as it effectively decomposes waste. Vermicompost has been analysed to physicochemical parameters like pH, and the level of macronutrient, and micronutrient content namely nitrogen, phosphorous, potassium, iron, copper, manganese and zinc analyses between the 30th and 60th day of control (raw soil), kitchen and paper waste vermicomposting. The vegetable plant Alternanthera sessilis, commonly known as sessile joy weed or Ponnanganni, has been used to test and investigate the effectiveness of vermicompost. The plant growth parameters, especially root length, shoot length, and number of leaves has been studying. Finally, a comparison was made with plants growing on the 30th &60th days of kitchen waste vermicompost and the 30th & 60th days of paper waste vermicomposting. In final results, the plant obtains maximum growth in kitchen waste vermicompost as a result of Alternanthera sessilis (sessile Joyweed) growth on the 30th and 60th days. The kitchen waste vermicompost contains a higher amount of NPK content than the control and paper waste vermicomposts. Consequently, the Alternanthera sessilis plants thrived on the kitchen wastes.

Evaluating Properties of Green Concrete Produced Using Waste Marble Powder, Quarry Dust, and Paper Pulp

AbstractIndustrial waste locks are used as raw materials to reduce harmful effects on the environment and improve environmental performance. Marble clay powder can be used as a filling aid and can fill voids in concrete structures. This article will show you how to use a maximum natural sand alternative in concrete with marble powder and quarry dust. The challenge of the 21st century is to change to a new form that can support the natural system. This necessitates a radical rethinking of how to give the community infrastructure and housing. Making a concerted effort to develop novel, innovative, and alternative construction materials may be necessary. Jungles of concrete around cause's impact on the Environment and it would result in climate change. Mankind must avoid the use of things that are detrimental to the environment. So in this paper, it is decided to address the issue by adopting the use of the green concrete concept which is environmentally friendly. Green concrete is concrete made up using industrial wastes such as marble powder, quarry dust, wood ash, paper pulp, etc. Green concrete, which is capable of sustainable development, helps to reduce the consumption of natural resources, energy use, and environmental pollution. Green concrete is more cost‐effective than ordinary concrete and reduces the cost of resultant concrete by 14%–20%. It is also observed that the alkali‐aggregate reaction and sulfate attack resistance of concrete are both significantly improved. Green concrete is a useful tool for lowering environmental pollution and enhancing concrete's resistance to harsh conditions. All stages of infrastructure construction and rehabilitation will follow this trend of using new cement and techniques. Green concrete's adaptability and its performance derivatives will meet a variety of future needs.

FACTORS INFLUENCING UNHOLY PRACTICES OF INDISCRIMINATE DUMP SITE IN WARRI-SOUTH, DELTA STATE, NIGERIA

The increasing number of indiscriminate dump sites in Warri-south in Delta state is worrisome and adversely affecting the living standard and health conditions of its growing populace. This study seeks to investigate the factors that influence unholy practices of indiscriminate waste disposal and to seek appropriate measures for mitigating or curbing this menace. It employs the cross-sectional research methodology. A sample size of 100 respondents from households living in Warri is used while a structured questionnaire with a three Likert scale is the research instrument for data collection. Exploratory Data analysis is employed to extract insights to explain the menace of dump site increase and the factors that significantly influence it. The results show that domestic waste such as food, paper, glass, and plastic waste is on the increase due to key influencing factors such as poor waste management laws, lack of waste facilities, poor training of waste collectors, and household attitudes towards waste disposal. Waste segregation and recycling were countermeasures to address waste disposal.

Study on Nitrogen Migration during Co-Pyrolysis of Melamine-Impregnated Paper Waste and Camellia Oleifera Shell

Melamine-impregnated paper waste (MIPW) is an unavoidable byproduct of the melamine-impregnated paper production process, and it must be urgently disposed. In this paper, due to its high N content, MIPW was used as a N source to co-pyrolyze with camellia oleifera shell (COS). By changing the proportion of MIPW in the raw materials, the migration path of the N was studied during the co-pyrolysis process. X-ray photoelectron spectroscopy (XPS), elemental analysis (EA), total nitrogen analysis (TN) and ultraviolet spectrophotometry were used to determine the content and the types of N-containing components in raw materials and products. The results showed that during the co-pyrolysis process, the N in MIPW and COS would be converted into different types of N-containing components, and the proportion of MIPW in raw materials directly impacts the product distribution and the N migration path. With the increase in the proportion of MIPW from 10 to 50 wt.% (daf, mass ratio), the proportion of N in raw materials that migrated into the solid phase decreased from 27.58 to 16.31 wt.%, while that which migrated to the gas and liquid phases increased from 24.92 and 47.50 wt.% to 25.97 and 57.72 wt.%, respectively. The proportions of N in the raw materials that changed into pyridinic-N, pyrrolic-N and graphitic-N in the solid phase and N2-N in the gas phase were decreased. The proportions of NH3-N and HCN-N in the gas phase and NH3-N and organic-N in the liquid phase were increased. Moreover, synergies were observed during the co-pyrolysis process, which affected the N migration path in the raw material. This study will provide policy directions and theoretical support for the comprehensive utilization of MIPW and COS.