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This study investigates the impact of incorporating lime mud (LM) as a filler material to develop sustainable, cementless ultra-high performance concrete (UHPC) by replacing silica powder (SP) and silica sand (SS) at varying percentages. Flowability analysis reveals that LM, with its distinctive particle size, influences flow characteristics differently at different replacement levels. Compressive strength was improved by 5.4% with 30% SP replacement, showcasing the role of LM in nucleation, as well as its particle size advantage. The heat of hydration analysis indicates that LM likely influences the early curing stages, enhancing reactivity and nucleation. TGA analysis also confirms that LM plays a role in hydration reaction, influencing weight loss and hydration peaks. The mercury intrusion porosimeter results show the impact of LM on pore distribution, with 30% for SP and 50% for SS replacements, favoring denser matrices. Life cycle assessment (LCA) demonstrates reduced CO 2 emissions and favorable environmental performance, highlighting the sustainability potential of LM replacements. Overall, the incorporation of LM in UHPC shows promise in terms of enhancing its mechanical properties and environmental sustainability. [Display omitted] • Lime mud (LM) in UHPC boosts material strength, leading to denser, more effective concrete. • LM enhances hydration, flowability, and refines pore structure. • High LM ratios in UHPC increase sustainability and reduce CO 2 emissions. • LM's use in UHPC significantly advances its mechanical properties and eco-friendliness. [ABSTRACT FROM AUTHOR]

Highlights • Pozzolanic reaction within the novel non-portland binder was compared with OPC. • Conversion of AFt to AFm in the binder was confirmed by TG/DTA and FT-IR analysis. • Reduced density of C-H phase within the novel binder after long term curing revealed. Abstract The development and production of new materials requires advanced analytical characterisation to explain the relation between the physico-chemical structure of the material and its properties. Highly integrated microelectronic structure analysis of surfaces with laser beams and X-ray fluorescence aided devices are found to be helpful for providing important information, including the interrelationships between physical, chemical, mechanical and durability characteristics of the new developed products. In most instances no single technique provides all the needed information and hence simultaneous application of several techniques becomes necessary. This study was aimed for hydration analysis, characterization and evaluation of a new novel non-Portland binder (NPB) with waste paper sludge ash (PSA) using FTIR and TG/DTA. The progressive formation of hydration products within the non-Portland binder was identified and their microstructural characteristics were analysed. The stable and non-expansive nature of secondary ettringite formation was also identified after a period of 365 days curing. [ABSTRACT FROM AUTHOR]

• Lignin additive extracted using H 2 SO 4 (L-S) had high phenolic content and pH value. • Asphalt with L-S additive had the lowest reduction of crossover modulus due to aging. • Incorporating L-S into asphalt reduces the increase of asphaltene fraction due to aging. • FTIR test is more sensitive in measuring the lignin antioxidant performance than DSR and GPC. The main objective of this research is to investigate the effectiveness of lignin bio-additives derived from black liquor paper pulp as asphalt antioxidants. Two lignin bio-additives, H-L and S-L, were developed by acidifying black liquor with hydrochloric and sulfuric acid. The laboratory aging procedures used in this study included the Rolling Thin Film Oven and the Ultraviolet Chamber methods. The crossover modulus (|G* c |) and linear amplitude sweep (LAS) were measured using a Dynamic Shear Rheometer (DSR). Gel Permeation Chromatography (GPC) was also used to characterize the molecular size distribution of the asphalt binder. The combination of carbonyl and sulfoxide aging indices was measured using Fourier Transform Infrared (FTIR) spectroscopy. The S-L modified binder (S-LMB) demonstrated superior aging resistance compared to both the control binder (CB) and the H-L modified binder (H-LMB) by exhibiting the lowest reduction in |G* c |. Furthermore, the LAS test results showed that S-LMB provided the best resistance to aging due to the lowest decrease in fatigue life with age conditioning, followed by CB and H-LMB, with rates of 11%, 13%, and 16%, respectively. The GPC results also confirmed the efficacy of the S-L bio-additive as an antioxidant, exhibiting the lowest increment in asphaltene proportion attributed to age conditioning. The FTIR measurements successfully captured the antioxidant capability of both H-L and S-L bio-additives, with S-L performing better than H-L. Overall, the results suggest that S-L demonstrates superior antioxidant performance compared to H-L. [ABSTRACT FROM AUTHOR]

Green liquor dregs wastes coming from pulp and paper production are currently disposed in landfills at a huge cost for industry and the environment. In this work, a novel and more sustainable waste management strategy is proposed. Dregs were used for the first time as fine filler in the production of biomass fly ash-based geopolymeric mortars. The influence of the dregs incorporation amount on the fresh (geopolymer kinetics and mortars workability) and hardened-state (mechanical resistance, water absorption and capillary water absorption) properties of the mortars was evaluated. Although dregs incorporation reduce the flow workability (up to 19%), their presence and amount did not significantly alter the geopolymerization kinetics. Additionally dregs-containing mortars exhibited enhanced tensile (up to 71%) and compressive strength (up to 34%), and lower water absorption in comparison with the reference mortar. These results demonstrate the feasibility of using dregs as fine filler in geopolymers production. Moreover the mortars were produced using mainly biomass fly ash waste as aluminosilicate source which further reduces the environmental impact of the pulp and paper industry. [ABSTRACT FROM AUTHOR]

This paper reports the results of an exploratory experimental study to manufacture eco-friendly lightweight bricks through binary mix of paper mill sludge (PMS) and soil. The pre-manufacture activities include mineralogical, chemical, thermal and index properties characterisation of two kinds of soils (laterite and alluvial) and PMS. The mix ratio between PMS and soil was varied (0%, 5%, 10%, 15% and 20%) and two firing temperatures 850 °C and 900 °C were tested in order to emulate the typical conditions of a kiln. The performance of incorporating PMS into the mix was tested by evaluating properties such as linear shrinkage, compressive strength, water absorption, mass loss on ignition, and bulk density of bricks as recommended by the relevant Indian and ASTM standard codes. X ray diffraction results confirmed that the addition of PMS does not show any phase transformation and only enhances the porosity thereby leading to weight reduction. Based on the results, an optimum mix of 10% PMS with both soil types was found suitable for brick production at a firing temperature of 900 °C. Results obtained in this study will be helpful to brick industry for commercial production of PMS incorporated bricks leading to sustainable use of resources. [ABSTRACT FROM AUTHOR]

• Titanate coupling agents reduce particle-polyol mixture viscosity more than 2 times. • Titanate coupling agents form hydrophobic monomolecular layer on the particle surface. • Coupled paper waste particles increase compressive and tensile strengths. • Coupled paper waste particles initiate nucleation process in particle-polyol mixture. Current efforts are focused on transforming renewable resources into advantageous polymers and the utilisation of waste for the same application and others. However, the utilisation of waste into polymer systems causes forming mixtures with high viscosities; therefore, this study analyses different types of titanate coupling agents (TCAs), TCA-L44, TCA-L38 and TCA-K44, and their effects on the rheology of bio-based polyol premixes filled with paper waste particles and the physical-mechanical properties and microstructures of polyurethane foams (RPUFs). It is found that TCAs improve the dynamic viscosity of polyol premixes by a factor of two. Based on the scattering of the apparent density results, TCA-L44 and TCA-K44, at amounts of 1–3 wt%, ensure an even distribution of waste particles, while TCA-L38 does not show evidence of coupling. Compared to RPUF without TCAs, the apparent density increased on average from ∼65 to ∼69 kg/m3 for TCA-L44, to ∼71 kg/m3 for TCA-L38 and to 69 kg/m3, indicating a weak cross-link effect. The compressive strength increases by an average of 6.5–9.1% and the tensile strength increases by 26.0–42.2% when TCA-K44 is used, while the water absorption decreases by up to ∼62% and the water vapour diffusion resistance factor decreases by ∼39% when TCA-L44 is used. [ABSTRACT FROM AUTHOR]

• Combined effects of extruded brick compositions with paper sludge and expanded perlite were characterized. • The use of additives in bricks has significantly affected their thermo-physical and mechanical properties. • The effects of process parameters on brick properties were investigated with a new mathematical modeling approach. • Fired brick samples showed good thermal insulation performance. • Produced exruded bricks have good potential for energy saving. Lightweight bricks produced with addition of different additive materials such as expanded perlite (EP) and recycling paper sludge (RPS) waste have been accomplished by a pug mill. Porous fired bricks were produced by using organic and inorganic additives such as paper waste and expanded perlite as pore-makers. In the experimental study, the seventeen mixture sets were prepared with Box-Behnken experimental design procedure of two additive ratios and firing temperatures. The brick samples were produced with shaping by extrusion method and firing at 850, 950 and 1050 °C for two hours after drying. Physical characteristics such as bulk density, apparent porosity and water absorption, and also, compressive strength, thermal conductivity and microstructural properties of brick samples were studied. Influences of process parameters on brick properties were investigated with a detailed neuro-regression analysis. In conclusion, the best brick composition (10 % EP + 10 %RPS by weight) in terms of thermal conductivity corresponding to acceptable mechanical properties was optimized. Accordingly, the compressive strength values of all samples are around 10 to 27 MPa. Also, the samples with high additive content (especially 10 %RPS + 5 %EP sample) exhibited the lowest thermal conductivity value (0.432 W/mK) due to the low firing temperature. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate some physical and mechanical properties of the paper mill (PMS) and spruce planer shaving added cement boards. Also the effect of sludge type in consequence of waste water treatment technique on properties of wood-cement boards (WCB) was investigated. The wood/cement ratios were used as 1/3, based on the oven dry weight for the WCB manufacture. PMS was used up to 20% wt of total composite based on organic (wood) and inorganic (cement) amounts. Black sludge has shown more improvement than grey sludge on properties of WCBs, which indicates the anaerobic waste treatment technique is more effective for additive in WCB. The modulus of rupture and elasticity values of the WCBs with 5% of grey sludge, 5% and 10% of mixture of grey and black sludge were acceptable limits according to EN 634-2 standard. The mechanical strengths of all WCBs with black sludge were found above the specified EN standard. This suggests that PMS depending on sludge type may be used up to 20% wt of total composite weight for the commercial production of WCBs, which could expand the raw material base for this panel product. [ABSTRACT FROM AUTHOR]

Due to increasing generation of solid wastes from papermaking industry, major concerns arise about the disposal of the solid wastes and their adverse impacts on environments, in which the disposal of paper sludge massively produced from paper mills has become one of the most serious solid waste problems worldwide. In this study, laboratory experiments were conducted to evaluate the feasibility and applicability of incorporating solid wastes from paper mills into controlled low strength material (CLSM), in which fly ash was used as a substitute for cement, bottom ash was added by partially replacing fine aggregate, and paper sludge was treated as a fibrous admixture. Results show that both fly ash and bottom ash could be effectively used in production of CLSM mixtures with desired performances. By limiting the amount of cement used in the mixture, the ultimate strength of CLSM could be controlled for easy excavation. Fly ash could effectively increase flowability of the mixture, thus improving self-compactibility. Both bottom ash and paper sludge had an adverse effect on the flowability. The strength of CLSM was reduced when a higher content of fly ash was incorporated to replace cement, while the strength was increased when more river sand was replaced with bottom ash. Due to a high water absorption and poor dispersibility of paper sludge, the CLSM made with additional paper sludge exhibited a relatively low flowability and a reduction in strength. However, with proper mixture design, paper sludge could still be effectively used in CLSM. [ABSTRACT FROM AUTHOR]

• RCF wastes brick achieves 24% lower thermal properties than the control brick. • RCF wastes brick requires 10% lower firing temperature than the control brick. • Utilizing as-received waste materials requires zero grinding energy, benefiting manufacturers and cutting emissions. • Lower firing temperature saved $158,460 by cutting 417 tonnes of CO 2. Building materials drive the global economy, yet face severe environmental hurdles: resource depletion, greenhouse gas emissions, and waste generation. In order to mitigate the impact from these challenges, authorities seek sustainable and eco-friendly alternatives as an urgent need. This study focuses on the utilization of as-received rejected contaminated fines (RCF) obtained from the yellow bins' waste (paper) recycling process, in brick production. Diverse tests assessed the brick performance, including compressive strength, absorption rate, thermal conductivity, 3D CT scanning for morphological analysis, and durability analysis. Additionally, a leachate analysis was performed to evaluate the environmental implications. Economic benefits, particularly the reduction of CO 2 emissions, were also evaluated. The findings confirmed that as-received waste can be utilized for fired clay brick production without the need for pulverization. The novel brick product made with as-received RCF waste exhibited superior thermal characteristics (up to a 31.25 % reduction compared to control bricks) while meeting the essential compliance requirements outlined by national standards. Moreover, each firing cycle led to a potential value of up to USD 158,460 through a reduction of 417 tonnes of CO 2 , resulting from a 9.5 % reduction in firing temperature (1000 °C). The results from this study offer valuable insights into the potential of using RCF waste as a sustainable alternative in the brick manufacturing industry. This alternative could address the soaring demand in the current market, resolve the escalating solid waste crisis, and mitigate clay shortages, while providing a sustainable solution for the brick industry. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate influence of calcination and cooling conditions on pozzolanic reactivity of waste paper sludge. Calcined paper sludge (CPS) is prepared by different temperatures of calcination, duration of calcination and cooling methods. Pozzolanic activity of CPS was investigated by using API (Assessed Pozzolanic Activity Index) and SAI (Strength Activity Index) in accordance with ASTM C618 -17 (KS L 5405) and consumption of Ca(OH) 2 hydrate in mortars with CPS in detail, and compared to that of commercial fly ash (FA) and blast furnace slag (BFS) used in the concrete industry. Results revealed CPS produced from waste paper sludge had excellent pozzolanic activity compared with commercial pozzolanic admixtures such as FA or BFS. Their pozzolanic activity was most excellent in calcination temperature of 700 °C, calcination duration of 2 h and cooling method of water quenching. SAI (%) of mortar with CPS produced under optimal conditions was 96% at 28 days of age, and satisfied the quality of fly ash (Class F) as specified in ASTM C618 -17 (KS L 5405). There was linear relation between API (%) and SAI (%) of mortars with CPS, and the correlation coefficient was relatively good as 0.8 at 28 days of age. The API method is recommended as rapid and appropriate evaluation of the pozzolanic activity of the CPS. [ABSTRACT FROM AUTHOR]

In the paper, the impact of paper production waste (primary sludge, or PS) on the properties of cement pastes and mortars is discussed upon. Some specimens were formed with fine PS fraction that replaced a part of cement content in them (5%, 10%, 15%, or 20%); in other specimens, coarse fraction of sludge (2/4) was used and a part of content of fine filler (sand) was replaced by PS. The properties of mixtures, such as water content required for cement paste of normal consistence, the setting time, exothermic temperature, flow diameter and plunger penetration, were established. In addition, the properties of hardened mortar, such as its density, flexural strength and compressive strength, were established. The microstructure of hardened specimens was examined as well. It was found that PS retarded hydration processes and reduced exothermic temperature; in addition, it reduced the flow diameter and the plunger penetration. While assessing the properties of hardened mortar, it may be stated that 5% PS waste might be used for replacement of a part of cement content. [ABSTRACT FROM AUTHOR]

In the present work, unshredded waste newspaper based composites have been prepared in polyester resin matrix. Reinforcing material, waste newspaper is characterized by chemically, X-ray diffraction (XRD) methods, Fourier transform infrared spectroscopy (FTIR) and tensile properties. Three different fibre content composite samples, namely 25%, 34%, and 50% (by weight) are prepared by hand lay-up techniques. Water absorption and thickness swelling tests are conducted by immersing composite samples in distilled water at room temperature. It is found that the percentage of moisture uptake and thickness swelling are increased as the fibre volume fraction is increased due to the high cellulose content. The tensile, flexural and interlaminar shear strength properties of water immersed samples are investigated and compared with dry composite samples. It is observed that after swelling the mechanical properties of composites are found to decrease with increase in percentage moisture uptake. [ABSTRACT FROM AUTHOR]

Highlights • Lime sludge utilization in concrete, mortars, fired bricks, ceramics and cement. • 10–30% cement replacement in concrete and mortars by lime sludge is optimum. • 25–30% replacement of fine aggregates by lime sludge is optimum. • Bricks and ceramic production with lime sludge conserves less energy. • Lime sludge eco clinker synthesizes with less carbon footprint and temperature. Abstract This review paper encompasses the inclusive approach of lime sludge valorization in construction materials. Research studies based on cement and aggregate replacement by lime sludge concludes that 10–30% lime sludge is gainfully utilized in sustainable concrete and mortar. Additional prospect for lime sludge application in construction material is the production of cement and ceramics. Significant use of lime sludge in combination with supplementary cementitious materials such as silica fume, nanosilica and fly ash is recommended for the production of cement components and ceramics. The recommendations are also suggested in accordance with the outcome of the study. [ABSTRACT FROM AUTHOR]

Abstract: The use of paper-mill residuals in concrete formulations provides an alternative to landfill disposal. A response surface statistical methodology was carried out to model the influence on the slump and compressive strength of concrete containing paper-mill residuals with and without Class F fly ash replacement. The variables considered in this study included the water/cement ratio (w/c), paper-mill residual content and fly ash content to total cementitious material (FA/CM). The performance of the derived models to achieve good balance between the workability and compressive strength were further discussed by using the contour diagrams. The results showed that the compressive strength of concrete containing paper-mill residuals could be predicted from the referred slump value. [Copyright &y& Elsevier]

Abstract: Cotton waste results from the mechanical processing of raw cotton in yarn mills. Recycle Paper Mills constitute 30% of total pulp and paper mill segment in India. With 85% average efficiency of Recycle Paper Mills, 15% waste is produced annually. Recycle Paper Mills waste and cotton waste has been utilized to make Waste Crete Bricks. It helps in solid waste management, generate additional revenue and help in earning carbon credits. Waste Crete Bricks with varying content of cotton waste (1–5wt.%), Recycle Paper Mills waste (89–85wt.%) and fixed content of Portland cement (10wt.%) have been prepared and tested as per IS 3495 (Part 1–3): 1992 standards. The characteristics of raw materials, which is the base material for Waste Crete Bricks, have been determined using XRF, TG–DTA, and SEM. TG–DTA indicate that bricks is thermally stable up to a temperature of 280°C while SEM monographs show its porous and fibrous nature. The bricks meet of IS 3495 (Part 1–3): 1992. [Copyright &y& Elsevier]

Abstract: Sustainable recyclable paper and composite materials can be ideal choices for the construction of temporary structures for both exhibition spaces or for rapid-recovery shelters in emergency operations. The unique engineering and sustainable features of these structures need to be considered as an integral part of the design process from the conceptual phase. Engineering studies to analyze these structures should be as important as the overall artistic and architectural vision. This paper examines the use of environmentally creep-formed paper tubes for the design, construction, and exhibition of, “Portals to an Architecture”, a large temporary outdoor sculpture. [Copyright &y& Elsevier]

• New material from cellulose and paper production process, concrete waste and lime production wastes. • Axial resistance reached 4.81 MPa in 3-day age samples, 8.75 MPa in 180 days, and 9.61 MPa in 365 days. • By methods of XRD, SEM and EDS were founded the processes of the materials hardening. • Utilization of industrial wastes has high environment and economic efficiency. The mechanical and physical properties of the composites developed from dregs, grits, and lime mud of the Kraft cellulose and paper production process (55–75%), concrete waste (10–25%) and lime production waste (0–25%), far exceeded the demands of Brazilian standards for bricks, blocks, and road-base construction materials. The study of the developed composites structure by XRF, XRD, SEM, EDS, and LAMMA methods demonstrated that new mainly amorphous formations were responsible for all attained properties. The industrial application of these construction materials would introduce excellent efficiency from an economic and environmental points of view. [ABSTRACT FROM AUTHOR]

• Long-term natural environment experiments of composite ice were performed. • The cumulative effect of composite ice sublimation rate was explored. • A dynamic model for composite ice sublimation prediction was proposed. • The changes in the mechanical properties of composite ice were tested. The climatic adaptability of ice-shell architecture under long-term natural influence remains underexplored. This study investigates the weatherability of paper fiber reinforced ice (PFRI) as envelopes, including the changes in the sublimation mechanism and mechanical properties changes. The PFRI specimens were layered poured and exposed to nature. The sublimation rates, climatic parameters, and stress–strain data were recorded. The results suggest that PFRI sublimation is a dynamic process with cumulative effects. A calculation model is proposed to predict sublimation in engineering. Considering fibre escape, PFRI with 2% or 3% fibre content has better weatherability, with a 30% decrease in elastic modulus on the sunny side and a 15% decrease on the shaded side. [ABSTRACT FROM AUTHOR]

Abstract: Recycle paper mills (RPM) contribute 30% of total pulp and paper mill segment in India. With 85% average efficiency of RPM, 5% waste (RPMW) is produced annually. RPMW which otherwise is land filled has been utilized to make construction bricks that serves a purpose of solid waste management, new revenue generation and earning carbon credits. RPMW-cement combination low carbon foot print bricks with varying composition of cement (0–20%wt) have been prepared and tested as per ASTM C 67-03a standards. RPMW has been characterized using X-ray fluorescence (XRF), thermogravimetric and differential thermal analysis (TG–DTA), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). TG–DTA confirms thermal stability till 280°C whereas SEM monographs show the pores and fibrous nature. From experimentation it is observed that waste-create bricks (WCB) prepared using RPMW-cement combination is light weight, shock absorbing and meets compressive strength requirements of ASTM C 67-03a. The brick making procedure being simple can be undertaken as rural entrepreneurship by unskilled labors of developing countries. [Copyright &y& Elsevier]