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The organic matter present in six industrial wastewaters (pulp and paper mill, brewery, textile, dairy, slaughterhouse effluents and a municipal landfill leachate) has been studied in this work using three analytical techniques: excitation-emission matrix fluorescence (EEMF), proton nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform infrared spectroscopy (FTIR). The pulp and paper mill effluent shows characteristic signals of the presence of lignins, carbohydrates and carboxylic acids, as well as sulfate, carbonate and sulfonates (coming from surfactants used in the cleaning of tanks). The main constituents of the brewery effluent are peptides and proteins coming mainly from spent yeast and diatomite filters (the presence of the latter was confirmed by Sisingle bondO bands in the FTIR spectrum). The municipal landfill leachate is characterized by the majority presence of humic substances (typical of an old landfill) and a residual presence of small peptides, amino acids and carboxylic acids. Additionally, several inorganic compounds were identified by FTIR, such as nitrate, sulfate, phosphate and cyanide ions. The textile effluent from a cotton-based industry contains carbohydrates, carboxylic acids and sulfonates, which can act as auxochromes in the textile industry. The dairy effluent comprises amino acids and small peptides coming from the biodegradation of milk and whey in addition to carbohydrates (lactose) and carboxylic acids (mainly lactic acid). The presence of tyrosine-like peaks B in the EEMF spectrum of the slaughterhouse effluent indicates the existence of small peptides and amino acids coming from the biodegradation of blood proteins. Additionally, residual glucose, fatty acids, phosphate and sulfate were also identified in this effluent.

This study's focus was to develop a potential pathway for recycling of the paper mill sludge compost (PMSC) in brick making. Composting reduces the paper mill sludge (PMS) moisture content considerably and shredding becomes easier. The addition of PMSC leads to an increase of porosities in bricks and makes them lighter, besides delivering energy to the firing process from burning organics. Lighter construction materials help minimize construction outlay by reducing labour and transportation costs and lesser expense on foundation construction. The variability in the experimental data and the brick properties were investigated for two types of soils, typical in the brick industry of India (alluvial and laterite soil), blended with PMSC in five mix ratios (0%, 5%, 10%, 15% and 20%). The samples of oven-dried bricks were fired at two different temperatures (850 and 900 °C) in an electrically operated muffle furnace representing typical conditions of a brick kiln. Various properties of bricks were analyzed which included linear shrinkage, bulk density, water absorption and compressive strength. Conclusions were drawn based on these properties. It was found that the addition of PMSC to the alluvial and laterite soil by up to 10% weight yield mechanical properties of fired bricks compliant with the relevant Indian and ASTM codes. Toxicity characteristic leaching procedure (TCLP) tests showed that PMSC incorporated fired bricks are safe to use in regular applications as non-load-bearing and infill walls. This study is timely in light of the European Green Deal putting focus on circular economy. Besides, it fulfills the objective of UN sustainable development goals (SDG). © 2021 Elsevier Ltd

The seemingly paradoxical phenomenon of workers’ resistance to health and safety measures has been explained in various ways, for example through production or efficiency pressure, risk-taking behaviours or problematic safety cultures. This article addresses resistance but analyses it through the lens of hierarchical and social accountability. In a case study of a Swedish paper mill, a health and safety programme is resisted by workers even though it enjoys support from the local trade union. Explanations for this is found in the socialising form of accountability that conditions how workers perceive of work-related health and safety. The aspects of work identity, facilitation and visibility are identified and understood in terms of accountability. Who you are, how you perform work, and what is visualised is filtered and evaluated through horizontal relationships rather than in terms of hierarchical accountability to the company.

The conventional application of a pulp and paper mill, in which black liquor is typically concentrated and burnt, is compared with the upgrading gasification route for methanol (MeOH) and dimethyl ether (DME) co-production. This comparison is made in terms of exergy efficiency and environmental impact indicators, under different utilities supply scenarios. The combined energy integration and exergy analysis is used to identify the potential improvements related to the decarbonization and mitigation of the process irreversibility. The exergy efficiencies of the conventional scenario and the integrated plants average 40% and 45%, respectively, while the overall emission balances vary from 1.97 to -0.07 tCO2/tPulp, respectively. These results reinforce the relevance of the electricity import from the Brazilian mix for pushing upwards the share of renewable energy resources in the production of traditionally fossil-based chemicals and fuels, which could be an important decision variable in favor to the exploration of forest-based integrated biorefineries.

Highlights • UASB was proposed for RPMW anaerobic treatement under mesophilic conditions. • Start-up up of the UASB reactor was completed in the 24 days. • 80,76 % COD and 90 % TS were removed at an OLR of 7,27 g COD/L d. • At optimal OLR of 8.31 g COD/L d was required to produce 62.51 L/d biogas. • For HRT 15.14 h, after reactor start-up 80.63 % of COD was removed. • The average biogas composition was 72.98 % CH4, 19.76 % CO2, 0.9 % O2., The anaerobic digestion (AD) has become an alternative source and an attractive treatment method. Up-flow Anaerobic Sludge Blanket (UASB) digester has been designed to treat the Recycled paper mill wastewater (RPMW) in Morocco. This paper provides a research on anaerobic digestion of RPMW using UASB technology. The UASB digester was designed following the characterization of wastewater and the feed rate, with the volume of 70 liters. The UASB reactor treating the RPMW was operated for 130 days with minimal overload problems. The experiments were carried out in the mesophilic temperature (37 °C) at different organic loading rates (OLR). A daily analysis was performed to ensure the efficiency of the digester. In this study, the AD experiment was performed in continuous mode with an effluent inlet flow rate equal to 1 L/h. Using the optimal OLR value 5.18 g COD/Ld and with an effluent 5,7 g COD/L, a biogas yield of 92 N mL/g COD removed (at normal temperature and pressure) was obtained during the RPMW anaerobic treatment. The reactor was operated at an optimal hydraulic retention time (HRT) of 15.14 h with a biogas production volume of the optimal value 62.5 L/d. These results indicate that RPMW can be effectively treated in a UASB reactor with the advantage of producing biogas. We tested our system with RPMW, to see the production capacity of the UASB system, which the objective is to develop the system for the industrial scale.

Interest in water treatment by electrochemical methods has grown in recent years. Electrochemical oxidation has been applied particularly successfully to degrade different organic pollutants and disinfect drinking water. This study summarizes the effectiveness of the electrochemical oxidation technique in inactivating different primary biofilm forming paper mill bacteria as well as sulfide and organic material in pulp and paper mill wastewater in laboratory-scale batch experiments. Three different electrodes, boron-doped diamond (BDD), mixed metal oxide (MMO), and PbO2, were employed as anodes. The impact on inactivation efficiency of parameters such as current density and initial pH or chloride concentration of synthetic paper machine water was studied. The electrochemical behavior of the electrodes was investigated by cyclic voltammetry with MMO, BDD, and PbO2 electrodes in synthetic paper mill water as also with MMO and stainless steel electrodes with biocides. Some suggestions on the formation of different oxidants and oxidation mechanisms were also presented during the treatment. Aerobic paper mill bacteria species (Deinococcus geothermalis, Pseudoxanthomonas taiwanensis, and Meiothermus silvanus) were inactivated effectively (>2 log) at MMO electrodes by current density of 50 mA/cm2 and the time taken was 3 min. Increasing current density and initial chloride concentration of paper mill water increased the inactivation rate of D. geothermalis. The inactivation order of different bacteria species was M. silvanus > P. taiwanensis > D. geothermalis. It was observed that inactivation was mainly due to the electrochemically generated chlorine/hypochlorite from chloride present in the water and also residual disinfection by chlorine/hypochlorite occurred. In real paper mill effluent treatment, sulfide oxidation was effective with all the different initial concentrations (almost 100% reduction, current density 42.9 mA/cm2) and also anaerobic bacteria inactivation was observed (almost 90% reduction by chloride concentration of 164 mg/L and current density of 42.9 mA/cm2 in 5 min). Organic material removal was not as effective when comparing with other tested techniques, probably due to the relatively low treatment times. Cyclic voltammograms in synthetic paper mill water with stainless steel electrode showed that H2O2 could be degraded to radicals during the cathodic runs. This emphasizes strong potential of combined electrochemical treatment with this biocide in bacteria inactivation in paper mill environments. The results of the experiments showed that electrochemical oxidation could be used in paper mill waters for planktonic bacteria removal. Applying this technique together with some biocides can enhance the oxidation process, keeping the paper mill pipelines clean of slime formed by bacteria. Electrochemical oxidation is also a promising preliminary or tertiary treatment process in pulp and paper mill wastewater treatment, especially against refractory organic compounds which cannot be removed by biological processes.

This chapter highlights the importance of anaerobic digestion in pulp and paper mill waste (PPMW) treatment. Due to increasing environmental concerns and strict laws about the effluents from industries, it becomes imperative to use such a technology. PPMW contains a vast amount of organic contaminants that are recalcitrant. Postaerobic treatment, a considerable amount of sludge is generated, and to cope up with this, anaerobic digestion, which results in much-reduced sludge volumes, is one of the best methods. Anaerobic digestion of PPMW offers additional benefits through the generation of renewable value-added bioproducts such as biogas, biomethane, biohydrogen, and biofertilizer, along with the treatment of waste. The present chapter describes the importance of anaerobic treatment of PPMW for both sludge and wastewater and the simultaneous generation of value-added products. In the end, the various challenges associated with anaerobic treatment and their mitigation strategies are also discussed.

In the present manuscript, novel effluent treatment processes for pulp and paper mill effluents are divided into two categories: a) those involving the use of chemical additives and b) those which are free of such chemicals. It is especially of high importance for pulp and paper industry to adopt the most efficient and cost-effective treatment methods. This paper critically reviews the recent studies on the treatment of pulp and paper mill effluents while providing suggestions for further studies on the application of various physic-chemical and biological methods for the treatment of such complex effluents containing a number of recalcitrant pollutants. Keywords: Pulp and paper industry, Industrial effluents, Chemical additives, Non-additive treatment processes

The process of bioconversion of solid organic wastes through vermicomposting justifies the environmental message for sustainability such as reduce, recycle and reuse of wastes. In the present study, wastes derived from two different types of paper mill sludge (primary and secondary), was used for their bioconversion through the vermicomposting process using an indigenous species of earthworm (Perionyx excavatus). The maturity and stability stage of vermicompost production was assessed using FT-IR, GC-MS and TG analyses. During vermicomposting, different biochemical functional groups present in the wastes have shown differential chemical alteration and turnover as revealed by FT-IR spectroscopy. This study has also confirmed the trend of biodegradation of complex substances like lignin, cellulose, proteins etc. and thereby demonstrates the extent of mineralization. TG spectral analysis had revealed a mass loss of 80% and 71% in vermicompost produced from primary and secondary sludge respectively. GC-MS studies have also shown the presence of several humic acids like octadecanoic acid, heptadecanoic acid etc. in the decomposing substances demonstrating as an indicator of the maturity of products. This was further confirmed by the decrease of humification index which focuses the combined action of both earthworms and microbes in the degradation of organic wastes. The present study has highlighted the role of an indigenous earthworm in converting specific industrial wastes especially by recording the point of maturation using humic acids an indicator of the quality of decomposing of wastes following several instrumental applications.

In this work, a granular activated carbon (GAC) was produced using primary paper mill sludge (PS) as raw material and ammonium lignosulfonate (AL) as binder agent. PS is a residue from the pulp and paper industry and AL is a by-product of the cellulose pulp manufacture and the proposed production scheme contributes for their valorisation together with important savings in GAC precursors. The produced GAC (named PSA-PA) and a commercially available GAC (GACN), used as reference material, were physically and chemically characterized. Then, these materials were tested in batch experiments for the adsorption of carbamazepine (CBZ), sulfamethoxazole (SMX), and paroxetine (PAR) from ultra-pure water and wastewater. Even though GACN and PSA-PA possess very similar specific surface areas (S) (629 and 671 m g, respectively), PSA-PA displayed lower maximum adsorption capacities (q) than GACN for the pharmaceuticals here studied (6 ± 1–44 ± 5 mg g and 49 ± 6–106 ± 40 mg g, respectively). This may be related to the comparatively higher incidence of mesopores in GACN, which might have positively influenced its adsorptive performance. Moreover, the highest hydrophobic character and degree of aromaticity of GACN could also have contributed to its adsorption capacity. On the other hand, the performance of both GACs was significantly affected by the matrix in the case of CBZ and SMX, with lower q in wastewater than in ultra-pure water. However, the adsorption of PAR was not affected by the matrix. Electrostatic interactions and pH effects might also have influenced the adsorption of the pharmaceutical compounds in wastewater., This work was funded by FEDER through Compete 2020 and by national funds through FCT by the research project PTDC/AAG-TEC/1762/2014. Vânia Calisto and Marta Otero also thank FCT for a postdoctoral grant (SFRH/BPD/78645/2011) and support by the FCT Investigator Program (IF/00314/2015), respectively. Thanks are also due for the financial support to CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), to FCT/MEC through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020

The wide occurrence of pharmaceuticals in aquatic environments urges the development of cost-effective solutions for their removal from water. In a circular economy context, primary paper mill sludge (PS) was used to produce activated carbon (AC) aiming the adsorptive removal of these contaminants. The use of low-cost precursors for the preparation of ACs capable of competing with commercial ACs continues to be a challenge. A full factorial design of four factors (pyrolysis temperature, residence time, precursor/activating agent ratio, and type of activating agent) at two levels was applied to the production of AC using PS as precursor. The responses analysed were the yield of production, percentage of adsorption for three pharmaceuticals (sulfamethoxazole, carbamazepine, and paroxetine), specific surface area (S ), and total organic carbon (TOC). Statistical analysis was performed to evaluate influencing factors in the responses and to determine the most favourable production conditions. Four ACs presented very good responses, namely on the adsorption of the pharmaceuticals under study (average adsorption percentage around 78%, which is above that of commercial AC), and S between 1389 and 1627 m g . A desirability analysis pointed out 800 °C for 60 min and a precursor/KOH ratio of 1:1 (w/w) as the optimal production conditions., This work was funded by FEDER through COMPETE 2020 and by national funds through FCT by the research project PTDC/AAG-TEC/ 1762/2014. Thanks are also due for the financial support to CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), to FCT/MCTES through national funds (PIDDAC), and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. The work was also developed within the scope of the project CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (UID/ CTM/50011/2013), financed by national funds through the FCT/MEC. Vânia Calisto also thanks FCT for her postdoctoral grant (SFRH/BPD/ 78645/2011). Marta Otero and Sérgio Santos thank support by the FCT Investigator Program (IF/00314/2015 and IF/00973/2014, respectively).

This work aimed to assess the fixed-bed adsorptive performance of a primary paper mill sludge-based granular activated carbon (PSA-PA) for the removal of pharmaceuticals, namely carbamazepine (CBZ), sulfamethoxazole (SMX) and paroxetine (PAR), from water. The breakthrough curves corresponding to the adsorption of CBZ at different flow rates and in two different matrices (distilled and municipal wastewater) were firstly determined, which allowed to select the most favorable flow rate for the subsequent experiments. The fixed-bed adsorption of CBZ, SMX and PAR from single and ternary solutions in wastewater showed that the performance of PSA-PA was different for each pharmaceutical. According to the obtained breakthrough curves, the poorest bed adsorption capacity, either from single or ternary solution, was observed for SMX, which may be related with electrostatic repulsion at the pH of the wastewater used (pH ~ 7.3–7.7). Also, the bed adsorption capacity of PSA-PA for SMX, in the ternary solution, was notoriously lower compared to the single solution, while it slightly decreased for CBZ and even increased for PAR. The regeneration studies showed that the CBZ adsorption capacity of the PSA-PA bed decreased about 38 and 71% after the first and the second thermal regeneration stages, respectively. This decline was comparatively larger than the corresponding reduction of the PSA-PA specific surface area (S), which decreased only 5 and 25% for the first and second regeneration stages, respectively, and pointed to the lack of viability of more than one regeneration stage., This work is a contribution to the project RemPharm (PTDC/AAG-TEC/1762/2014) funded by FCT – Fundação para a Ciência e a Tecnologia, I.P., through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. Thanks are also due for the financial support to CESAM (UID/AMB/50017/2019), to FCT/MEC through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. Vânia Calisto and Guilaine Jaria thank FCT for their grants (SFRH/BPD/78645/2011 and SFRH/BD/138388/2018, respectively); Marta Otero and Vânia Calisto are also thankful to FCT for the Investigator Program (IF/00314/2015) and the Scientific Employment Stimulus (CEECIND/00007/2017)

Paper and pulp industries consume huge amount of resources like wood and water every year and creates large amounts of solid wastes and waste water that have to be treated. Different forms of wastes are produced such as particle, solid, gas, and water during paper production. The developed wastes are usually not treated properly and waste water is mostly allowed to mix with water resources like river. So identification of some suitable methodologies to treat these wastes in an environmental-friendly way and to extract the energy from these wastes is the need of the day. This chapter focuses on the history of paper making, paper making methodologies, forms of waste generated along with their sources, and characteristics followed by the techniques for converting these wastes into useful energy. Incineration, gasification, pyrolysis, anaerobic digestion, and biodiesel production methodologies for converting paper mill wastes into energy are discussed and it is found that anaerobic digestion is a commonly used method for wastewater, whereas incineration is for solid wastes. The possibility of producing biofuels from these wastes was also found as feasible.

Publisher Summary Recovered paper, or waste paper, can come from a number of different sources, including internally at the paper mill. A number of different terms are used to indicate when in the life cycle of the paper that it is returned for recycling. Recovered paper collection is done in a number of different ways, depending on the type of paper being collected and the source of the paper. In general, preconsumer recycled paper is easier to collect as it tends to be concentrated in specific manufacturing locations and also tends to be much more homogeneous. These collections, often of the form of cuttings, trimmings and over issues, are typically baled and packaged directly at the collection site with little additional processing needed. Paper recycling is a key raw material for the papermaking process, representing a significant portion of the fiber used. However, because of the degradation of the fibers through the papermaking and recycling process, the limit to the amount of paper being recycled is slowly being approached. In addition, there are a number of grades of paper that are currently not recycled and will not be in the foreseeable future. This is particularly true for such personal care products such as toweling and tissue. Future improvements in recycling will need to deal mainly with the fiber quality issues.

Paper mills yield large volumes of sludge materials which pose an environmental and economic challenge for disposal, despite the fact that they could be a valuable source for cellulose nanofibres (CNF) production. The aim of the study was to evaluate the production process and properties of CNF prepared by mechanical fibrillation of never-dried and dried paper mill sludge (PMS). Atomic force microscopy (AFM) showed that average diameters for both never-dried and dried paper sludge nanofibres (PSNF) were less than 50 nm. The never-dried and dried sludge nanofibres showed no statistical significant difference (p>0.05) in strength ∼92 MPa, and ∼85 MPa and modulus ∼11 GPa and ∼10 GPa. The study concludes that paper mill sludge can be used in a dried state for CNF production to reduce transportation and storage challenges posed on industrial scale.

A one-year leaching experiment has been conducted in order to assess the effectiveness of several amendments on metal immobilization in mine tailings from an old Pb/Zn mining area of Central Spain (San Quintín mine). Demineralized water was used as leaching solution, selecting doses equivalent to the annual rainfall conditions of the studied area. Columns with mine tailings without any amendment and others treated with 10% of sugar foam (SF), 15% of drinking water treatment sludge (DWS), 30% of paper mill sludge (PMS) and 15% of olive mill waste (OMW) were used. SF, DWS and PMS amendments increased the pH of leachates from values of approximately 4 to around neutrality. Additionally, the release of sulfate ions from the oxidation of pyritic residues was decreased in some extent by SF and DWS amendments. Metal leaching was effectively reduced by the amendments reaching overall decreases with respect to the unamended columns of 79–96% for Pb, 36–100% for Zn, 50–99% for Cu and 44–100% for Cd. The effect of the amendments in leachate pH, sulfate concentration and metal release from mine tailings was kept throughout the whole experimental period. Our results showed that the application of different organic and inorganic amendments based on by-products and waste materials may be a feasible alternative for the restoration of soils around abandoned metal mines., Se ha realizado un experimento de lixiviación de un año para evaluar la efectividad de varias enmiendas sobre la inmovilización de metales en relaves mineros de una antigua zona minera de Pb / Zn en el centro de España (mina San Quintín). Se utilizó agua desmineralizada como solución de lixiviación , seleccionando dosis equivalentes a las condiciones de precipitación anual del área de estudio. Columnas con relaves mineros sin enmienda y otras tratadas con 10% de espuma de azúcar (SF), 15% de lodos de potabilización (DWS), 30% de lodos de papelera (PMS) y 15% de residuos de almazara (OMW) fueron usados. Las enmiendas SF, DWS y PMS aumentaron el pH de los lixiviados de valores de aproximadamente 4 a aproximadamente neutralidad. Además, el lanzamiento deLos iones sulfato de la oxidación de residuos piríticos disminuyeron en cierta medida por las enmiendas SF y DWS. La lixiviación de metales se redujo efectivamente con las enmiendas que alcanzaron disminuciones generales con respecto a las columnas sin enmendar de 79–96% para Pb, 36–100% para Zn, 50–99% para Cu y 44–100% para Cd. El efecto de las enmiendas en el pH del lixiviado, la concentración de sulfato y la liberación de metales de los relaves de la mina se mantuvo durante todo el período experimental. Nuestros resultados mostraron que la aplicación de diferentes enmiendas orgánicas e inorgánicas basadas en subproductos y materiales de desecho puede ser una alternativa viable para la restauración de suelos alrededor de minas de metales abandonadas.

Water appears to play several essential roles during manufacture of paper. The quality of fresh water entering a paper machine system can affect both process efficiency and paper quality, contributing to, or being responsible for, various problems. About 85% of the water used in the pulp and paper industry is used for processing, ultimately producing large volumes of contaminated wastewater. All processing cycles in paper production are connected directly or indirectly by water loops. The objectives of the water circuit system are to offer the required volume rate and quality of water for each consumer and to treat and/or bleed out water containing detrimental substances. Water circuits with loop designs and circuit closure are presented in this chapter.

Pulp and paper industry produces massive amounts of sludge from wastewater treatment, which constitute an enormous environmental challenge. A possible management option is the conversion of sludge into carbon-based adsorbents to be applied in water remediation. For such utilization it is important to investigate if sludge is a consistent raw material originating reproducible final materials (either over time or from different manufacturing processes), which is the main goal of this work. For that purpose, different primary (PS) and biological sludge (BS) batches from two factories with different operation modes were sampled and subjected to pyrolysis (P materials) and to pyrolysis followed by acid washing (PW materials). All the materials were characterized by proximate analysis, total organic carbon (TOC) and inorganic carbon (IC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and N2 adsorption isotherms (specific surface area (SBET)and porosity determination). Sludge from the two factories proved to have distinct physicochemical properties, mainly in what concerns IC. After pyrolysis, the washing step was essential to reduce IC and to considerably increase SBET, yet with high impact in the final production yield. Among the materials here produced, PW materials from PS were those having the highest SBET values (387-488 m2 g-1). Overall, it was found that precursors from different factories might originate final materials with distinct characteristics, being essential to take into account this source of variability when considering paper mill sludge as a raw material. Nevertheless, for PS, low variability was found between batches, which points out to the reliability of such residues to be used as precursors of carbon adsorbents. L'Oreal Portugal published

The activated sludge process is the most common treatment for pulp and paper mill effluents. Process modelling is a powerful tool to increase the knowledge of wastewater treatment plants, with the benefits, for instance, of reducing costs and time for making decisions on process improvement. Frequently, ASM models are used to describe the pulp and paper mill effluents treatment. These types of effluents usually have low nutrients contents, which affect the biomass growth and in consequence, the process efficiency. In this work, a mathematical model which includes the dynamic influence of adding nutrients to the aerobic stage of a paper mill industry is retrieved, identified, calibrated and validated, in order to gain knowledge on the process for efficiency, in which the nutrients (ammonium phosphate) are added by an auxiliary inflow. Due to practical purposes, the developed model considers only seven out of nineteen biological processes in the ASM2. To get a reliable mathematical model for the process, we followed a five-step methodology that includes: (a) problem definition, (b) experimental data obtainment, (c) model construction (d) model calibration and (d) linear error propagation for uncertainty analysis. The reduced ASM2 contains 31 parameters that were calibrated by a non-linear regression with real data plant. This step was applied to four operational scenarios, with and without variation of the KLa parameter, as well as with and without effluent recirculation of the clarifier. The results show that the reduced ASM2, developed here, shows good responses that can be identified to the real process. Therefore, it can be used confidently for operational decisions for improvement of the process.

A large variety of external treatment technologies—primary treatment, secondary treatment [aerated lagoon, activated sludge moving bed bioreactor (MBR), biofiltration, anaerobic treatment], and tertiary treatment—being used for pulp and paper mill effluents are presented in this chapter. The comparison of the treatment efficiencies for different wastewater treatments is also presented.

Various organic and inorganic hazardous substances are commonly originated during the processing of virgin or recovered fibers (RCFs), when the pulp and paper (P\&P) are produced. Hence, pulp and paper industry (PPI) strongly need to employ advanced waste treatment processes as a powerful tool to comply with the stringent environmental regulations in one hand, and to increase their profitability in the current declining P\&P markets, on the other hand. Among the treatment alternatives, anaerobic digestion (AD), is an interesting cost-effective alternative with a small environmental footprint and has been increasingly adopted by the PPI to reach this goal. However, the application of AD to deal with wastes generated in P\&P mills has been restricted due to a number of limitations, regarding the anaerobic reactor design and the operating conditions. Hence, the optimization of the AD performance would be a crucial step in order to increase the economic benefits, and also to satisfy the strict environmental protection standards. To this end, this paper presents an overview on the current state of the developments associated with AD treatment of P\&P mill wastes to assess the applicability of this treatment process for the management of this type of complex wastes. In this context, suggestions are provided to maximize both biogas production and removal efficiency, focusing on the relationship between waste composition and reactor design and operational conditions, which will enhance methane capture and contribute to prevent global warming. (C) 2016 Elsevier B.V. All rights reserved.

This work describes the single adsorption of seven pharmaceuticals (carbamazepine, oxazepam, sulfamethoxazole, piroxicam, cetirizine, venlafaxine and paroxetine) from water onto a commercially available activated carbon and a non-activated carbon produced by pyrolysis of primary paper mill sludge. Kinetics and equilibrium adsorption studies were performed using a batch experimental approach. For all pharmaceuticals, both carbons presented fast kinetics (equilibrium times varying from less than 5 min to 120 min), mainly described by a pseudo-second order model. Equilibrium data were appropriately described by the Langmuir and Freundlich isotherm models, the last one giving slightly higher correlation coefficients. The fitted parameters obtained for both models were quite different for the seven pharmaceuticals under study. In order to evaluate the influence of water solubility, log Kow, pKa, polar surface area and number of hydrogen bond acceptors of pharmaceuticals on the adsorption parameters, multiple linear regression analysis was performed. The variability is mainly due to log Kow followed by water solubility, in the case of the waste-based carbon, and due to water solubility in the case of the commercial activated carbon.

Papermaking deposits can be classified as being organic, inorganic, or microbiological. Most paper machine deposits contain a combination of some or all of these major component types. Although inorganic deposits tend to be more of a problem in the stock and flow-piping systems of the paper mill, organic deposits tend to be more problematic in the headbox, wet end, and press section of the paper machine. These contaminants form tacky deposits that can plug forming fabrics and wet press felts. Microorganisms in paper mill systems take two forms: planktonic and sessile. Planktonic organisms do not readily cause problems in the system; however, in the sessile form, these same organisms can become problematic. Inorganic and organic deposits offer a readily available food source for sessile organisms, which attach themselves to deposit surfaces. Several of these organisms classified as slime formers are able to secrete a protective polysaccharide coating around themselves known as biofilm. The slime formers, in combination with inorganic and organic process additives and contaminants, can form deposits that coat process equipment and create sheet quality and runnability problems. In addition to slime formers, anaerobic bacteria can form under deposits. The most common type of anaerobic bacteria found in paper mills is sulfate-reducing bacteria, which is capable of converting sulfate in the system to highly corrosive hydrogen sulfide.

Recycled fibre is a major source of raw material for the modern recycled paper mill. Stickies are a major obstacle to manufacturing high-quality paper. They are natural components of the recycled fibre used by the mills. Stickies are tacky, hydrophobic, pliable organic material found in recycled paper systems. They exhibit a broad range of melting points and different degrees of tackiness depending on their composition. Stickies are composed of a variety of materials including adhesives, styrene–butadiene latex, rubber, vinyl acetate and hot melts, etc. The variable nature of stickies and the variability of the composition of recycled fibre used by paper and board mills make them more difficult to control. Stickie contaminants are a costly problem both for recyclers of market pulp and for the papermakers using it. Stickies challenge the process of using recycled or secondary fibre sources. In addition, they tend to deposit on machine surfaces, fabrics, wires, felts and rolls, which leads to runnability problems such as paper breaks at the press. If not controlled, stickies can also lead to paper quality issues such as holes, sheet defects and high dirt counts. Several methods have been proposed for controlling stickies. Chemical methods involve dispersants, polymers and absorbents. Mechanical methods use screens, cleaners, dissolved air flotation and washing stages. Enzymes are the sustainable alternative to chemicals. They efficiently convert the stickies into more manageable components, thereby improving machine performance. More importantly, enzymes have the ability to improve the recycled paper’s quality in terms of spots, holes and breakage as well as preventing damage from stickies. Several case studies explain the effect of using enzymes in mill situations, producing results such as a 90% reduction in stickies and an increase in brightness across the deinking facility, production performance improvements, a reduction in the use of cleaning solvents and significant reduction in downtime caused by stickies. The Optimyze product line from Buckman is successfully being used in many mills around the world.

The coagulation-flocculation method has been used to treat pulp and paper mill wastewater. Single-coagulant, single-flocculant, and coagulant–flocculant processes have been investigated. Treatment efficiency was studied taking into consideration various effects such as pH, type and dosage of coagulant and flocculant, settling characteristics, and water recovery. Alum and polyaluminum chloride (PACl) were used as coagulants. Nine cationic and anionic polyacrylamides (PAMs) of various molecular weights and charge densities were chosen as flocculants. For the single coagulant, both alum of dosage 1000 mg/l and PACl of dosage 500 mg/l achieved higher than 90% treatment efficiency in turbidity reduction, TSS removal, and COD reduction. From the nine PAM flocculants studied, 5 mg/l of the cationic polyacrylamide, Organopol 5415, with high molecular weight and low-charge density produced the best flocculation efficiency: 95% turbidity reduction, 98% TSS removal, and 93% COD reduction. The sludge volume index (SVI) was 14 ml/g. For the coagulation–flocculation process, alum showed better treatment efficiency than PACl when combined with Organopol 5415. The results showed 99.7% turbidity reduction, 99.5% TSS removal, and 95.6% COD reduction, with an SVI of 37 ml/g and a settling time of 12 seconds. A pilot scale study gave very similar results. The water recovery from the process was 96.3%.

International audience; Microbial bioanodes were formed in pulp and paper effluent on graphite plate electrodes under constant polarization at -0.3 V/SCE, without any addition of nutriment or substrate. The bioanodes were characterized in 3-electrode set-ups, in continuous mode, with hydraulic retention times from 6 to 48 h and inlet COD from 500 to 5200 mg/L. Current densities around 4 A/m2 were obtained and voltammetry curves indicated that 6 A/m2 could be reached at +0.1 V/SCE. A theoretical model was designed, which allowed the effects of HRT and COD to be distinguished in the complex experimental data obtained with concomitant variations of the two parameters. COD removal due to the electrochemical process was proportional to the hydraulic retention time and obeyed a Michaelis-Menten law with respect to the COD of the outlet flow, with a Michaelis constant KCOD of 400 mg/L. An inhibition effect occurred above inlet COD of around 3000 mg/L.

The closure of water circuits within pulp and paper mills has resulted in a higher contamination load of the final mill effluent, which must consequently be further treated in many cases to meet the standards imposed by the legislation in force. Different treatment strategies based on advanced oxidation processes (ozonation and TiO2-photocatalysis), and their combination with biological treatment (MBR), are herein assessed for effluents of a recycled paper mill and a kraft pulp mill. Ozone treatment achieved the highest efficiency of all. The consumption of 2.4 g O3 L−1 resulted in about a 60% COD reduction treating the effluent from the kraft pulp mill at an initial pH = 7; although it only reached about a 35% COD removal for the effluent of the recycled paper mill. Otherwise, photocatalysis achieved about a 20–30% reduction of the COD for both type of effluents. In addition, the effluent from the recycled paper mill showed a higher biodegradability, so combinations of these AOPs with biological treatment were tested. As a result, photocatalysis did not report any significant COD reduction improvement whether being performed as pre- or post-treatment of the biological process; whereas the use of ozonation as post-biological treatment enhanced COD removal a further 10%, summing up a total 90% reduction of the COD for the combined treatment, as well as it also supposed an increase of the presence of volatile fatty acids, which might ultimately enable the resultant wastewater to be recirculated back to further biological treatment.

There is a significant opportunity now for investors to build, own, and operate biorefineries at existing pulp and paper sites that will work synergistically and economically for the pulp and paper mill owner and the biorefinery owner. The pulp and paper industry is the world’s largest nonfood biomass collection system. The pulp and paper industry is a mature industry producing low-margin commodity products. But it has the ideal infrastructure, experience, and resources to capitalize on the strategic interest in renewable fuels via the biorefinery. Industry leaders, investors, policy-makers, and others are now beginning to better understand the vital role to be played by biorefineries as we move from a fossil fuel-based energy economy toward a bio-based one. When properly located and operated, the potential of an integrated forest biorefinery is expected to be huge: a very attractive and synergistic business opportunity for both the colocated pulp and paper mill and the biorefinery itself. Biorefineries are a key pathway to our biofuture, displacing fossil fuels and supplying clean, renewable, and carbon neutral energy. Biorefineries fit very well at pulp and paper mills because of their inherent ability to gather and process biomass and create energy from biomass.

There are a growing number of process alternatives that should be considered for biorefinery implementation in a pulp and paper mill. The emerging biorefinery process options are hemicellulose preextraction, lignin precipitation, black liquor gasification (BLG), and tall oil extraction. Preextraction generates a feed stream for new bioproducts, while decreasing alkali consumption, increasing delignification rate, and reducing black liquor load. BLG and/or lignin precipitation are an integral part of the integrated forest biorefinery with the synthesis gas and precipitated lignin being the feed for liquid fuel and carbon fibers, respectively. The additional energy requirements of the integrated forest biorefinery would be met by gasification/combustion of waste biomass. For successful implementation of the forest biorefinery, there is a need to identify possible products that can be economically produced by a pulp and paper mill. To identify these products, process integration tools can be used. Once the products have been identified, a roadmap can be developed. The successful implementation of the forest biorefinery will in many cases require strategic collaborations with experts and will likely be mill-specific.

Pulp and paper mills are huge consumers of water and energy. Hence, much research works have been dedicated to simultaneous reduction of water and energy in the past decades. However, none of those works are addressing the brown stock washing system (BSWS), which is the core processing section that determines the amount of energy required in black liquor (BL) concentration. The latter is the largest energy consumption in a typical pulp and paper mill. Therefore, minimizing water consumption in the BSWS will lead to energy saving too. In this work, mass balances of the BSWS is first analyzed in a process simulation software (Cadsim), and adopted as the base case model for the study. Next, a mixed integer non-linear programming (MINLP) optimization model is developed to minimize the total annualized cost incurred in the project. The synthesized water network features significant reduction in both energy and water consumption in the BSWS.

Pulp mill sludge produced in the Cova da Beira region (Portugal) contains organic matter (11-47%), nitrogen (38-2560 mg N/kg) and phosphorus (167-370 mg P/kg), which may be valuable for increasing soil productivity. The levels of heavy metals are below the limits recommended by legislation and the amount of nitrogen and phosphorous to be introduced in soils does not present a risk for nutrient leaching. After identifying the environmental and technical restrictions on its application, an area of 1650 ha was identified where the sludge can be applied in forage crops, fruit trees, olive groves and vineyards. A suitable area was also found for a biosolids storage centre. The use of GIS allowed to define a sludge application index and to produce land-use suitability maps, which can be useful for sludge management.

Excilamps are new UV sources with great potential for application in wastewater treatment. In thepresent work, a KrCl excilamp emitting radiation at 222nm has been used for the photodegradationof 4-chlorophenol within a range of concentrations from 50 to 500mgL −1 . The photodegradation pro-cess has been shown to form two main photoproduct intermediates, benzoquinone and hydroquinone.Total removal of 4-chlorophenol was shown for all concentrations assayed, and, for both main interme-diates, residual concentrations of 20–30% of the initial concentration of 4-chlorophenol remained. Theirincreasing presence with increasing initial concentrations of 4-chlorophenol had the effect of decreasingthe removal efficiency of the photoproducts. In order to simulate the process and scale-up a simplifiedkinetic model has been developed and validated from the experimental data.© 2009 Elsevier B.V. All rights reserved. 1. IntroductionChlorophenols are usually found in the wastewaters of numer-ous industries including the pulp and paper, wood, steel and othermetals, petroleum refining, resins and plastic based industries,beingcommonlyreleasedfromtheseindustrialwastewaterstotheenvironment [1,2]. They are widely considered as priority pollu-tants and can be rather persistent causing severe environmentalproblems.OneexampleistheLakeBaikalecosystem(WorldNatureHeritage Site since 1996), where chlorophenols are released intothe lake as by-products of the bleaching of crude pulp with activechlorine in the Baikalsk pulp and paper mill located directly on thesouthern shore of the lake [3].Physical, chemical and biological methods have been utilisedin the removal of these toxic compounds, however, a definitivesolution remains [4–13]. Among the methods considered, photo-chemical degradation of the contaminants in water is of particularinterestandpotential.ThecombineduseofUVradiationandstrongchemical oxidizing agents constitutes one type of the advancedoxidation processes (AOPs), that can be particularly effective inthe removal of toxic chlorophenols from water and wastewa-ter [14–18]. Although there are numerous investigations on the

This chapter discusses several methods employed for the treatment of waste from paper and pulp industries. The paper and pulp process uses plenty of water, and the waste generated from this industry contains solvents, chlorinated compounds, resins, and most importantly lignin, which is highly resistant to degradation. Chlorinated compounds are also toxic to many microorganisms.. Conventional biological methods such as activated sludge and aerated lagoons help in reducing the chemical oxygen demand (COD) load and toxicity, but these methods cannot effectively remove the color from bleach plant effluents; in addition they consume energy for aeration. White rot fungus appears to be efficient in color removal. Anaerobic degradation is affected by the presence of sulfate. Destruction of adsorbable organic halogen is another aspect that needs to be addressed. Carrying out biodegradation at thermophilic conditions would be advantageous since the waste stream from the paper mill is generally around 50 o C but finding efficient microorganisms is still a research challenge.

11 pages, 2 figures, 4 tables.-- PMID: 12741600 [PubMed].-- Printed version published Apr 4, 2003., A comparative study of the performance of liquid chromatography (LC)–atmospheric pressure chemical ionisation (APCI)–mass spectrometry (MS) and gas chromatography (GC)–mass spectrometry techniques for the determination of resin and fatty acids from paper mill process waters was carried out. These compounds are responsible for the high toxicity of paper mill effluents and little research has been carried out regarding their analysis using mass spectrometric techniques. To prove the usability of GC and LC–MS, 16 treated and untreated water samples of recycle, kraft and pulp paper mills were analysed and good agreement was observed as regards to compounds detected and corresponding concentrations. This paper also reports the limits of detection, recoveries, reproducibility, linearity and precision using the two methods. GC–MS presented better selectivity and lower detection limits (below 0.2 μg/l), but derivatization of the extracts and the short life of derivatives (12–24 h) made the technique tedious and prone to high variations. Although LC–APCI–MS presented coelution of the non-aromatic resin acids, it also showed good sensitivity (limits of detection, The EU Energy, Environmental and Sustainable Development Program (CLOSEDCYCLE) Contract Number (EVK1-2000-00749) and Ministerio de Ciencia y Tecnología (PPQ2000-3007-CE) have supported this work.

Publisher Summary This chapter reviews current wastewater management strategies for pulp and paper mill effluents that fall into three categories: pre-bleaching technologies, bleaching technologies, and post bleaching technologies. A balanced use of all the strategies is required. Treatment before disposal of bleach effluents cannot be eliminated and it will continue to play an important role in complying with the standards prescribed. Among biological treatment technologies available, fungal treatment technology appears to have an edge over the other treatment technologies. To make the fungal treatment method economically feasible, there is a need to reduce the requirement of cosubstrate or to identify a cheaper cosubstrate. A quantitative study of extracellular enzymes is also required in order to gain insight into the possible enzymatic mechanism involved in the degradation of lignin-derived compounds present in the effluents. Use of white-rot fungi can serve as a prelude to bacterial treatment and enhance bacterial removal of organic chlorine and degrade the relatively higher-molecular-weight chlorolignins.

An integrated investigation on wastewater characterization and the environmental effects from the COGIDO pulp and paper mill in Bien Hoa Industrial Estate, Vietnam, a chlorine bleached soda integrated pulp and paper mill operating without a chemical recovery system, on the receiving water body was conducted during the rainy and dry seasons in 1993 and 1995. The pollution load from the mill was very high in terms of BOD, COD and SS (CODm: 58.7t/d; BOD: 33.3 t/d and SS: 25.1 t/d). The effluent toxicity was determined using four toxicity tests: the green micro-alga, Selenastrum capricornutum, Microtox (marine bacteria: Photobacterium phosphoreum), the duckweed, Lemna aequinoctialis, and fish (silver barb: Puntius gonionotus, and Tilapia: Tilapia nilotica). Selenastrum capricornutum was the most sensitive among the tested organisms. The mill toxicity emission rate (TER) was as high as 338 610 (Selenastrum test). The bleaching-pulp and semi-chemical pulp plants which contributed the largest pollution load to the total COGIDO effluent, therefore, were targeted for abatement measures. Physicochemical parameters as well as qualitative and quantitative aquatic organism composition for the river water were established. The BOD5 and COD values exceeded the potable surface water standard by a factor of 2 to 4. The species diversity and abundance of the phytoplankton, zooplankton and zoobenthos were found to be lower (20–40%) than that of unpolluted rivers in Vietnam, whereas pollution-indicator species increased up to four times during the dry season 1995.

The diagram constructed for selection of sampling methods indicates that, for a systematic error, E≤13%, grab sampling (GS) may be used to characterize effluents with variation coefficient of flow ≤120% and of contaminant concentrations ≤10%. For the whole studied range of variation coefficient of contaminant concentrations (2–82%), time-proportional compositing (TC) method may be applied with E≤10% for effluents characterized by variation coefficients in flow

This chapter discusses preparation of the stock prior to the headbox of the paper machine and describes numerous additives and fillers used to make paper. Wet end chemistry— the chemistry of the dilute aqueous solution of fibers, fillers, and additives— is also discussed. Knowledge of wet end chemistry helps predict retention of additives, drainage during papermaking, and the level of sizing of the final paper. Stock is the mixture of pulp, fillers, other papermaking materials, and water. The combination of all of the materials used to make paper is called furnish. Broke consists of paper trimmings and waste, paper not up to specification, and other paper that is often reused in the paper mill. A mill producing more than 10-15% broke is not operating efficiently. A typical stock preparation system for paper machines includes stock proportioning and stock cleaning. Additives are materials used to improve the finished paper itself or aid in the process of papermaking. Functional additives such as dyes, internal sizing agents, adhesives to increase wet or dry strength, and fillers are used to improve or impart certain qualities to the paper product and must be retained on the sheet to be effective. Control additives as biocides, drainage aids, retention aids, pitch control agents, and defoamers are added to improve the papermaking process, but do not directly affect the product and are not necessarily retained on the product.

The amount of endoglucanase, β-D-glucosidase and xylanase produced by the fungus D. squalens were found to be dependent on the source of carbon and on the presence of the Tween 80 in the growth medium. Growth on cotton cellulose enhanced the production of endoglucanase, β-D-glucosidase and xylanase in the culture filtrates relative to the other sources of carbon (Avicel cellulose, carboxymethylcellulose = CMC, paper mill sludge, sawdust of Pinus sp). The endoglucanase induced by CMC exhibits 76% of residual activity after 2 h at 80 °C, maintaining about 100% activity after 1 h at 50 °C, pH 5.0; it has a half-life of 17 min at 70 °C, pH 5.0. This enzyme shows optimal pH activity at pH 5.0 and pH stability between 4.0 and 6.36 where it exhibits a residual activity of more than 76%. The β-D-glucosidase component was isolated by chromatography on DEAE - Sephadex A-50.

Phanerochaete chrysosporium immobilized in calcium alginate gel was used in a fluidized bed reactor for the biobleaching of black liquor. The alginate-entrapped mycelium was activated for 6-24 h in the bioreactor, and different flow rates (10-30 ml h-1) were studied for the continuous biobleaching of black liquor. All the activation periods with different flow rates, resulted in poor reduction in colour and chemical oxygen demand than batch system.

Publisher Summary Undesirable characteristics of pulp and paper mill effluents include: the presence of a food source for microorganisms which would deplete oxygen in rivers if not at least partially removed (Biological oxygen demand, BOD); color discharges which detract from the appearance of a river or lake; suspended solids which make water appear murky; other materials such as fillers, acids, bases, and sludges, which may be sent to the sewer during mill upsets. The severity of the problem depends on the type of mill. Mills producing bleached kraft pulp discharge over 30,000 gallons per ton of pulp. Mechanical pulp mills discharge about 5,000 to 7,000 gallons of water per ton of pulp. In TMP mills the principal pollutants are derived from wood extractives including resin acids. Resin acids may be as high as 50-200 mg/L in untreated effluent, but may be decreased to 0.5mg/L with a high level of secondary treatment. Further materials contributing to air pollution include particulate matter from the boilers, lime kiln, and smelt dissolving tank; gaseous combustion pollutants such as carbon monoxide, nitrogen oxides, and volatile organics; odor consisting of reduced sulfur compounds in the kraft process; and sulfur dioxide from the recovery furnace and boilers using fuel containing sulfur.Sludges that are produced at paper mills must be disposed. These include the sludge from the primary clarifiers, sludge removed from secondary treatment of effluent, and sludge from clarification of deinking mill effluent.

Twenty-three volatile S compounds were identified from the exhaust gases of sulphate and semialkaline pulping processes of a pulp mill.

This paper presents the status of physicochemical treatment used by pulp and paper mills with special emphasis on technologies developed or advanced in the U.S.A. The paper is intended to provide a broad spectrum of approaches with sufficient detail to differentiate between the type of paper mill for which the process had application. The processes reviewed were not confined to end-of-pipe treatments but also include internal process modifications which found application during the decade of the 1970-1980. Where convenient, a brief history of the pioneering work is also presented.