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The South African pulp and paper industry generates an estimated 0.5 million tons of pulp and paper mill sludge (PPMS) annually. As PPMS is generated, it requires safe, efficient, and economical co...

Herein, paper mill waste sludge (PMS) from two different sources has been investigated to extract calcium hydroxide, Ca(OH)2 by a facile and inexpensive extraction process. This green process exploits typical chemical precipitation (CP) in an aqueous medium at room temperature to develop an economically and industrially viable technique for the effective utilization of calcium-containing waste sludge. PMS samples, collected from local paper mill plants of Bangladesh, were the main precursors wherein HCl and NaOH were utilized for chemical treatment. The as-synthesized products were analyzed by a variety of characterization tools including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, Scanning electron microscopy (SEM), and Energy Dispersive X-ray (EDX) elemental analyses. Our studies confirm that the extracted product contains Ca(OH)2 as a major content, albeit it also includes CaCO3 phase formed owing to the inescapable carbonation process from the surrounding environment. The particle size of the synthesized products is in the range of 450 - 500 nm estimated from SEM micrographs. The crystallite domain size of the same estimated from XRD analyses and was found to be ~47 nm and ~31 nm respectively for product-A and product-B considering major (101) Bragg peak of Ca(OH)2. The yield percentage of the isolated products is about 65% for samples collected from both sources.

In this study, we evaluated the effect of bamboo bleached kraft pulp (BKP) on the strength of the coloring paper used for pear paper bags. The characteristics of bamboo BKP were measured to compare them with those of softwood BKP and hardwood BKP. Handsheets from bamboo and hardwood BKPs were prepared at various mixing ratios, and their strengths were then analyzed. After that, a mill trial was performed to produce a prototype of coloring paper with bamboo BKP, and the effect of bamboo BKP on the strength of the coloring paper was finally determined. The initial freeness and fiber shape of bamboo BKP were similar to those of hardwood BKP, although the average fiber length and curl of bamboo BKP were higher than those of hardwood. As the mixing ratio of bamboo BKP increased, the strength of the handsheets increased, indicating the enhancing effect of bamboo BKP on the strength of coloring paper. As a result of the mill trial of coloring paper in the specialty paper mill, it was found that the tensile strength increased by 27.8% and burst strength by 20.0% when bamboo chemical pulp replaced 20% of the hardwood chemical pulp. Therefore, it was concluded that bamboo chemical pulp can replace and improve the strength of hardwood chemical pulp for manufacturing coloring paper.

Declining carbon (C) content in agricultural soils threatens soil fertility and makes soil prone to erosion, which could be rectified with organic soil amendments. In a 4‐yr field trial, we made a single application of three different organic sludges from the pulp and paper industry and studied their effects on cereal yield, soil C content, and fungal and bacterial composition. In laboratory rainfall simulations, we also studied the effects of the soil amendments on susceptibility to erosion and nutrient mobilization of a clay‐textured soil by measuring the quality of percolation water passing through 40‐cm intact soil monoliths during 2‐d rainfall simulations over four consecutive years after application. A nutrient‐poor fiber sludge reduced wheat yield in the first growing season, but there were no other significant effects on cereal yield or grain quality. An input of ∼8 Mg ha−1 C with the soil amendments had only minor effects on soil C content after 4 yr, likely because of fast microbe‐mediated turnover. The amendments clearly changed the fungal and bacterial community composition. All amendments significantly reduced suspended solids (SS) and total phosphorus (TP) concentrations in percolation water. The effect declined with time, but the reduction in SS and TP was still >25% 4 yr after application. We attributed the lower tendency for particle detachment in rain simulations to direct interactions of soil minerals with the added particulate organic matter and microbe‐derived compounds that stabilize soil aggregates. In soils with low organic matter content, pulp and paper industry by‐products can be a viable measure for erosion mitigation.

Oxidation of sulfate lignin and sludge-lignin (waste from Baikal Pulp and Paper Mill) in a stream of water–oxygen mixture and in air in the programmed heating regime is studied. Based on the temporal dependences of the power of resistive heaters and the temperature of the reactor wall, it is revealed that the maximum rates of lignin and sludge-lignin oxidation in an H2O/O2 mixture are reached at 613–643 K. The oxidation of both materials in the H2O/O2 mixture is completed at lower temperatures than in air. The temperature dependences of compositions of volatile and liquid products, including the content of phenols, are obtained. Using the mass-spectrometric analysis, it is shown that during oxidation in the H2O/O2 stream 90.3 and 79.5% of the carbon is removed from lignin and sludge-lignin, respectively, in the form of carbon oxides. The mechanisms of the transformation of heteroatomic components are discussed. The formation of hydrochloric and sulfuric acids in the course of sludge-lignin’s oxidation in the H2O/O2 stream causes the corrosion of stainless steel.

The main purpose of this study is to optimize the applicability of TiO2 nanoparticles for paper mill and pulp wastewater treatment under solar irradiation using response surface methodology, provided by the software package DOE. The principle independent parameters were TiO2 loading, pH, time and H2O2 concentration, and COD removal efficiency was chosen as desire response. To evaluate the influence of the parameters on the outputs, the quadratic formulation was applied and for determining the validation of developed models analysis of variance was utilized. The results represented the greatest COD removal was achieved 82%, approximately at pH of 8.1, TiO2 fraction of 0.83 g/L, H2O2 concentration of 2.4 ml/L and the contact time of 196 min.

The paper industry wastewater even after bio-treatment at industrial scale is a major source of aquatic and soil pollution due to various unknown compounds. Hence, the study has focused on the detection of residual organic pollutants from the bleached and unbleached paper mill wastewater and both sources showed endocrine-disrupting compounds. The toxicity test with Phaseolus aureus seed germination showed inhibition of seed germination and alpha-amylase activity >25% in bleached and unbleached paper mill wastewater. The LC50 of Tubifex tubifex was noted of >50% after 48 hours incubation test. This revealed that the wastewater discharged from bleached paper mill is more toxic than unbleached paper mill waste this might be due to the use of more chemicals during bleaching and pulping process. This study has revealed that there is need to treat both paper mill wastewaters adequately prior to discharge.

A good quality control system is important to be implemented to increase productivity and minimize defects in products. One of the quality control methods is failure mode and effect analysis (FMEA). This study uses the FMEA to identify the causes of the defects and recommend the prevention methods to overcome the causes of the defects in an Indonesian paper mill. The risk priority number (RPN) is calculated by multiplying the severity, occurrence, and detection of the failures that have been determined. Unsymmetrical and tainted products are the most dominant defects in the paper mill. An inappropriate machine setting is the cause of unsymmetrical products with the highest RPN of 343. The second highest RPN is problems with bleaching machines that caused tainted products with an RPN value of 216. This study offers suggestions to Indonesian paper mill to prevent and minimize defective products.

Lime mud, a kind of industrial waste that produced in paper mill, was proposed as CO2 sorbent in calcium looping process. The carbonation performance of the lime mud was investigated in a dual‐fixed bed reactor (DFR) and a thermogravimetric analyzer (TGA). The carbonation kinetics of the lime mud in the chemical reaction controlled stage was analyzed by a surface reaction‐controlled kinetic model. The results show that the lime mud presents much poorer carbonation performance during the chemical reaction controlled stage compared with the limestone, mainly due to the high content of chlorine in the lime mud. A prewash treatment process was used to decrease the chlorine content to mitigate the sintering of the lime mud when calcined at high temperature. After prewash treatment, the prewashed lime mud shows much higher CO2 capture capacity during the chemical reaction controlled stage compared with the lime mud. A prolonged carbonation process successfully further enhances the microstructure and improves the carbonation performance of the prewashed lime mud in the chemical reaction controlled stage. The lime mud can be effectively used as CO2 sorbent in calcium looping process after prewash treatment and the following prolonged carbonation treatment.

The present study was undertaken to know the effect of common mixed pulp and paper mill effluent discharge released from century pulp and paper mill Lalkuan, Nainital Uttarakhand on the blood morphology of Heteropneustes fossilis (Singhi). The various morphological changes were observed in the specimen, randomly collected with the help of cast net from (3 sites) different locations. The maximum changes were observed in the specimen collected from site 3 in compare to site 1 and 2 respectively. The formation of inclusion bodies, sickle cells, Cabot rings and ovalocytes were recorded along with nuclear fusion, membrane disruption and cell clumping of blood cells in the specimen collected from the site 3 (i.e. nearer to source of discharge) while in the specimen collected from site 2, the formation of tear drop cell, target cells, spherocytes and bi-nucleated cells were recorded along with the activity of cell clumping. The changes were found less in the specimen collected from site 1 in compare to the specimen of site 2 and 3 i.e. formation of ovalocytes, spherocytes and microcytes with the activity of membrane degeneration and agglutination in blood cells.

Paper can be manufactured without bleaching, but high quality white paper grades, which require bleaching, are in demand as well. In paper mills, oxidizing or reducing chemicals are utilized to bleach the pulp. In this study, the utilization of sodium perborate, instead of the generally used sodium dithionite, to brighten mechanically produced wood pulp was investigated. Sodium perborate was chosen, as it is an environmentally friendly chemical and is produced in Turkey - from tincal, one of the boron ores in Turkey. The experiments were performed at Milda Aksu Paper Mill, using fresh pulp. The amount of bleaching chemicals was adjusted so that the dry mechanical pulp contained 0.5-2% more active oxygen. These chemicals were used either alone or in combination to see their bleaching effects. It was seen that the use of 2% sodium perborate together with 1.5% hydrogen peroxide gave better ISO brightness values (68%) than that of the dithionite bleached (64%) pulps. Under these conditions, fringing and fiber to fiber bonding was more pronounced than in the case of the paper from dithionite bleached pulp, which shows the advantage of using perborate in the bleaching process. Besides, the physico-mechanical properties of the produced paper sheets increased noticeably.

A two-step process involving coagulation-flocculation followed by solar photocatalysis – based Advanced Oxidation Process (AOP) using TiO2-Reduced Graphene Oxide (TRGO) nanocomposite as catalyst ha...

The present study was undertaken to know the effect of common mixed pulp and paper mill effluent discharge released from century pulp and paper mill Lalkuan, Nainital Uttarakhand on the blood morphology of Heteropneustes fossilis (Singhi). The various morphological changes were observed in the specimen, randomly collected with the help of cast net from (3 sites) different locations. The maximum changes were observed in the specimen collected from site 3 in compare to site 1 and 2 respectively. The formation of inclusion bodies, sickle cells, Cabot rings and ovalocytes were recorded along with nuclear fusion, membrane disruption and cell clumping of blood cells in the specimen collected from the site 3 (i.e. nearer to source of discharge) while in the specimen collected from site 2, the formation of tear drop cell, target cells, spherocytes and bi-nucleated cells were recorded along with the activity of cell clumping. The changes were found less in the specimen collected from site 1 in compare to the specimen of site 2 and 3 i.e. formation of ovalocytes, spherocytes and microcytes with the activity of membrane degeneration and agglutination in blood cells.

The Lewis-Clark Valley is a rural area that includes the cities of Lewiston, Idaho and Clarkston, Washington and the surrounding areas. The largest industry in the Lewis-Clark Valley is a pulp paper mill located in Lewiston which emits particulate matter and odorous sulfur air pollutants. This study analyzed the Lewis-Clark Valley air composition and seasonal, temporal and spatial variations of volatile organic compounds (VOCs) from 2017 to 2018 to determine potential health risks of the paper mill emissions to the surrounding community. Both active and passive air sampling via sorbent tubes were analyzed by thermal desorption - gas chromatography-mass spectrometry (TD-GC-MS). Fifty VOCs including benzene, toluene, chloroform, dimethyl sulfide and dimethyl disulfide were measured in the ambient air of the Lewis-Clark Valley at ten different sites, totaling over 800 samples. In addition, passive sorbent tubes were deployed in 2018 to obtain monthly averages in Lewis-Clark Valley and three urban locations in Idaho and Washington for comparison. United States Environmental Protection Agency (2001) methodology was used to assess cancer risks in the community based on the upper confidence levels of five carcinogens and nine air toxics. The Lewis-Clark Valley had similar levels of benzene to urban areas but had a strong signature of chloroform and sulfides from the paper mill. The cumulative cancer risk was 2 x 10-6 - 11 × 10-6 mainly due to the compounds chloroform, benzene and carbon tetrachloride. The hazard index of other air toxics was less than one. Overall, these air pollutants were considered low risk to the local population.

Most Power departments are tasked with generating steam to support mill wide operations, gener-ate electricity, and reduce operating costs. To accomplish these tasks, power boilers generate high pressure steam that is reduced to intermediate and low pressures for process utilization in the mill by means of steam turbine generator extraction or pressure reducing valves. The most economical method to reduce steam pressure is the use of steam turbine generators, as electricity is generated from the steam when it is reduced in pressure. Electricity that is produced by these generators provides a substantial financial benefit and helps offset overall operational costs. To achieve tangible financial gains, the mill must evaluate the overall cost of steam production and the price of electricity. The current work provides a case study of power plant optimization that evaluated electricity production and steam production costs balanced with mill steam demand. Process and cost optimization led to a significant reduction in low pressure steam venting, resulting in reduced fuel consumption and reduced operating cost.

Controlling the size and rigidity of calcium carbonate became possible. HCCs were developed and manufactured by the in situ reaction of carbon dioxide and calcium oxide, which were already preflocculated together with GCC using ionic polymers before the reaction. HCC is deformable under pressure during the papermaking process, and its degree of rigidity can be controlled by adjusting the fraction of calcium oxide. The size of HCC can be further controlled by adjusting shearing force. The more the fraction of calcium oxide, the more rigid the HCC and the smaller the diameter of the HCC. When used in papermaking, HCC increased the tensile strength and bulk of paper simultaneously without lowering other essential paper properties, and its deformable nature under pressure improved paper smoothness. Saving chemical pulp by 10% by replacing it with HCC, which is 3–4 times less expensive than the chemical pulp, was demonstrated successfully without lowering the essential properties of paper. Implementation of HCC in the paper mill may result in saving chemical pulp, drying energy, and production cost. The paper mill may utilize the carbon dioxide from the mill stack after purification for HCC preparation.

The need is increasing in line with the high market demand for a product. One product that is widely used is paper. One of the recycled paper industries is PT. Pura Nusapersada Unit Paper Mill 7/8, where the production process uses water vapor from a coal-fired boiler. This process can produce ash that can pollute the air so that air pollutant control devices such as cyclones and wet scrubbers are needed. It is necessary to evaluate the efficiency of the cyclone and wet scrubber by knowing the specifications and working principles of the tool, the emissions produced, the effectiveness of the equipment, the factors that influence, problems, operation, and maintenance. The method used is direct observation, interviews, data in the form of documents, references, and routine reports. The cyclone used is a multi-cyclone type, and the wet scrubber is a venturi scrubber type. From the calculations that have been done, the efficiency of the Hitachi Boiler is 94.195%, and the Hamada II Boiler is 96.844%. The boiler produces emissions that meet quality standards for the Minister of Environment Regulation No. 07/2007. The efficiency calculation should be done once a year so that the quality of the equipment is monitored and does not pollute the surrounding air quality.

Objectives: The objective of the study was to study the compressive strength of the partially replaced paper mill waste in cement. Methods/ Statistical analysis: The concrete cube specimen were prepared for compressive strength test. In this study, the cement has been replaced with 20%, 30%, 40% and 50% of hypo sludge. The specimens were cured for two different ages (7 days and 28 days) and tested for compressive strength. The quadratic polynomial prediction equation was proposed using Response Surface Methodology (RSM). The prediction model was developed using the experimental output results. Thus, the prediction model facilitates the further research work to be conducted by researchers on paper mill waste replacement. The rate analysis was also further carried out to show the cost effectiveness of using the waste replacement in cement. Findings: The test was conducted on the compressive strength (7 days and 28 days) of control specimen (0%) and partial replacement of 20%, 30%, 40% and 50% of cement using the hypo sludge. Thus, 20% replacement of cement using hypo sludge has shown good compressive strength than the control specimen. The cost of 20% paper mill waste was less when compared to the cost of control specimen. Novelty/ Applications: The compressive strength of 20% partial replacement of paper mill waste in cement can be used in further construction. The prediction model can be used to predict the future compressive strength of partially replaced paper mill waste concrete. Keywords: Ordinary Portland cement; Paper mill waste; Hypo sludge; Partial replacement; RSM

Ultraviolet (UV) radiation systems are a common method of inactivating bacteria in municipal water treatment but has not been applied in a paper mill operations. Determining the feasibility of installing such a system is the purpose of this report. Directly treating a starch solution of sufficient concentration proved impossible as the transmittance required was far too low. Water used in the onsite water recycling facility’s cooling towers had a transmittance over 90% and so was very treatable. Lab scale testing with a designed 15 liter laboratory benchtop ultraviolet treatment system showed that UV treatment can reduce the aerobic bacteria count by two fold for up to 24 hour of operation and significantly lower results for 48 and 72 hour of operation. Therefore, UV treatment can be considered a valuable process for the treatment of cooling tower water.

Anaerobic-oxic (AO) systems have been extensively adopted for the biological treatment of wastewater from recycled paper mills, which is characterized by high chemical oxygen demand (COD) concentrations and contains hundreds of organic compounds. In this study, an up-flow anaerobic sludge blanket (UASB) served as the anaerobic treatment of recycled paper mill wastewater. Then, either a sequential batch reactor (SBR) or a sequential batch biofilm reactor (SBBR) were adopted as aerobic treatment to treat the UASB effluent respectively. Parameters such as COD, BOD5, and TSS were measured to compare the treatment performance of SBR and the SBBR. After 80 days’ operation, COD removal efficiency of SBR and SBBR were 21.79 ± 3.4% and 38.38 ± 2.69% respectively; TSS removal efficiencies were 20.84 ± 5.15% and 47.02 ± 5.84% respectively. The results indicated that SBR was effective for removing residual organic matter in UASB effluent. However, SBBR showed significant advantages for the removal of COD and total suspended solids (TSS), which are ascribed to the effective biomass retention and biofiltration of SBBR.

In this study, the viability of acetylation in cellulose fibers waste (CFW) from pulp and paper mill sludge was investigated in comparison to bleached cellulose fibers (BCF). Four acetylation metho...

The performance of an asphalt mixture does not only rely on its engineering properties. Yet, the service characteristics of an asphalt mixture do play an important role on the durability of pavemen...

An improved lab-scale anaerobic baffled reactor was developed to treat recycled paper mill effluent (RPME). In this study, analysis of modified anaerobic baffled reactor (MABR) performance in RPME ...

The paper presents the results of the analysis on measured parameters of harmonics at the node of the high-voltage network. The measurements were made at the node connecting the pulp-and-paper mill to the 220 kV supply network. This load is nonlinear and has a large capacity. Particular attention is paid to the distributions of the current and voltage harmonics. The paper clearly shows probabilistic properties of the measured parameters of harmonics

A novel strain, designated WH2-56, was isolated from a slime sample collected from a paper company along the Yangtze River during March, 2018. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain WH2-56 was related to members of the genus Planomicrobium. Cellulolytic activity of the sample was screened and confirmed by Congo red-polysaccharide interactions and examined by broth culture using filter paper (FP) with no starch as the sole carbon source. Field emission scanning electron microscopy (FE-SEM) was used to confirm the delicate morphological changes of FP during bio-degradation. Different cellulosic materials were used to measure biodegradation effects and optimum incubation conditions. The activity of FPase and carboxymethyl cellulase (CMCase) were checked by 3,5-dinitrosalicylic acid (DNS agents) with different carbon sources, which showed a peak at 0.62 U/mL of CMCase on day 4, and at 0.38 U/mL of FPase on day 5.

The thriving development of the paper industry leaves behind a great amount of pulp and paper mill sludge (PPMS), which constitutes a considerable source of pollution. Experts estimate that...