The Effectiveness of Potassium Permanganate in Oxidizing Hydrogen Sulfide and in Aiding Mechanical Dewatering of Pulp and Paper Industry Sludges

Introduction Odorous compounds have long been a significant problem faced by mills treating their own wastewater. This problem can be compounded when mechanical dewatering equipment is used to process primary and secondary sludges. Plainwell Paper Company, a competitive producer of fine printing and technical specialty papers, is no exception to this rule. Along with the start-up of their new waste water treatment facility, which includes an Arus-Andritz sludge dewatering machine, came an irritating and potentially harmful odor problem. It was determined that the major cause of the odor was hydrogen sulfide

Removal of recalcitrant organic compounds from an industrial complex effluent by heterogeneous Fenton-type treatment

Because of their chemical complexity, industrial chemi-mechanical pulping effluents are evaporated and burned, in spite of the high associated cost involved in these processes. The aim of this study was to remove recalcitrant compounds from this kind of wastewater using a Fenton-type treatment. The main parameters involved in the process and their influence on the results were determined. Homemade catalysts based on CuO, Fe2O3, NiO and ZnO, supported on γ-Al2O3 have been tested for catalytic oxidation, and the CuO/γ- Al2O3 catalysts showed the greatest effect on total organic carbon (TOC) reduction (52.7%). A series of twolevel factorial experiments was subsequently applied to evaluate the most favorable range of conditions for CuO/γ-Al2O3 application. The studied variables were hydrogen peroxide concentration ([H2O2], g/L), active phase content (metal oxide supported on alumina, %), mass of catalyst (metal oxide/alumina system, g), and reaction temperature (°C). The highest reduction of all parameters was obtained at the superior level of all variables with CuO/γ-Al2O3, achieving reductions of chemical oxygen demand (COD) and TOC between 40 and 50%. Increasing catalyst mass did not produce additional benefit. This variable has a significant effect only on the reduction of aromatic compounds. At its low level, reduction in aromatic content exceeded 80%. Color reduction was influenced only by temperature (maximum reduction of 90%)Fil: Covinich, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; ArgentinaFil: Felissia, Fernando Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; ArgentinaFil: Fenoglio, Rosa Juana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Area, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentin

Tratamento de águas residuais industriais com nanomateriais sintetizados para um ambiente sustentável

Quality of the final discharged effluents from industrial activities has been the subject of significant efforts over several decades to improve the performance of the methods applied for their treatment, either by physico-chemical, biological, or a combination of these processes. Among the emerging technologies, the application of various types of engineered nanomaterials (ENMs) has gained a particular attention in recent years. The present thesis aimed to carry out either experimental studies, surveys and critical reviews in order to synthesize the most sustainable nanomaterials for the treatment of recalcitrant pollutants from the content of industrial effluents. In parallel, the sustainability of other biological and physicochemical methods has been critically assessed and the most sustainable treatment methods have been suggested to be adopted by the industries. It was demonstrated in this thesis that the application of Tagguchi approach can considerably aid to control the properties of iron-based nanoscale particles synthesized by a liquidphase reduction process. Working with this system revealed that both the (reductant/Fe3+) ratio, (R), and the Fe3+concentration, [Fe3+], are the parameters that determine critical characteristics including particle crystalline phase composition, crystallinity and surface area although R has been revealed as the most important one. Nano zero valent iron particles with enhanced properties, synthesized by utilization of ultrasonic irradiation, was successfully tested to degrade organic dyes (methylene blue, as a case study) which are dominant in the wastewater from some industries such as textile factories. Recovery of the nanomaterials after being applied for the treatment purposes is also among the most important parameters for the selection and synthesis of the most sustainable nanomaterials for environmental applications. A novel ZnO/Fe3O4 on Bentonite nanocomposite prepared in this thesis showed acceptable photocatalytic decomposition of 2,4 dichlorophenol besides the ability to be recovered after being used. Magnetic nanocomposites were also tested for the degradation of AOXs from pulp and paper mill effluents and showed acceptable performance in such applications. A framework was also developed in this thesis for the sustainability assessment of the best available technologies to deal with industrial effluents, showing the efficiency of biological treatment methods to deal with industrial effluents although having some limitation to deal with phenolic industrial effluents. With a precise acclimatization process, very high efficiency for the biodegradation of phenol with a high degree of resistance to the shock of initial phenol concentration was achieved using activated sludge process. The results of a critical review, as the future outlook of this thesis, indicated the possibility of integration of engineered nanomaterials and also biological treatment with the membrane technologies in order to overcome the existing barriers for the rapid development of membrane technologies for the treatment of industrial effluents.A qualidade dos efluentes finais de atividades industriais tem sido, ao longo de várias décadas, objeto de esforços significativos para melhorar o desempenho dos seus métodos de tratamento, seja por via físico-química, biológica ou uma combinação destes. Entre as tecnologias emergentes, o recurso a nanomateriais sintetizados (ENMs) tem sido alvo de especial atenção nos últimos anos. A presente tese teve como objetivo realizar estudos experimentais, levantamentos de informação e revisões críticas, a fim de sintetizar nanomateriais sustentáveis para o tratamento de poluentes recalcitrantes existentes em efluentes industriais. Paralelamente, a sustentabilidade de outros métodos biológicos e físico-químicos foi avaliada criticamente, tendo-se sugerido os métodos de tratamento mais sustentáveis para serem adotados pelas indústrias. Foi demonstrado nesta tese que o recurso à abordagem de Tagguchi pode auxiliar consideravelmente no controlo das propriedades de partículas nanométricas à base de ferro, sintetizadas por um processo de redução em fase líquida. O estudo deste sistema revelou que tanto a razão (agente redutor/ Fe3+) como a concentração de Fe3+ são os parâmetros que determinam características críticas dos precipitados, incluindo a sua composição de fases cristalinas, grau de cristalinidade e área superficial específica. As nanopartículas de ferro de valência zero com propriedades melhoradas, sintetizadas pela utilização de irradiação por ultrasons, foram testadas com sucesso para degradar corantes orgânicos (azul de metileno como corante modelo) que são compostos dominantes nas águas residuais de algumas indústrias, designadamente de fábricas de têxteis. A recuperação dos nanomateriais após a sua aplicação em tratamentos de efluentes também é um dos aspectos mais importantes a ter em consideração na seleção e síntese de nanomateriais sustentáveis para aplicações ambientais. Um novo nanocompósito de ZnO/Fe3O4 sobre Bentonite, produzido neste trabalho, revelou uma capacidade aceitável para decomposição fotocatalítica do 2,4 diclorofenol, além da capacidade de ser recuperado após utilização. Testaram-se também nanocompósitos magnéticos na degradação de AOXs de efluentes da indústria do papel e celulose que evidenciaram um desempenho aceitável nessas aplicações. Definiu-se também nesta tese um contexto para a avaliação da sustentabilidade das melhores tecnologias disponíveis para lidar com efluentes industriais, tendo-se revelado a eficiência dos métodos de tratamento biológico para lidar com efluentes industriais, embora com alguma limitação para lidar com efluentes industriais fenólicos. Com um processo de aclimatação preciso, conseguiu-se uma eficiência muito elevada para a biodegradação do fenol, com alto grau de resistência ao choque da concentração inicial de fenol, utilizando-se o processo de lamas ativadas. Mediante uma revisão crítica da literatura, e como perspectivas de futuro a extrair do presente trabalho, aponta-se a possibilidade de integrar nanomateriais sintetizados e tratamento biológico nas tecnologias de membrana, para superar as barreiras actualmente existentes ao rápido desenvolvimento das tecnologias de membrana para o tratamento industrial efluentes.Programa Doutoral em Ciências e Engenharia do Ambient

Combined biological and advance oxidation processes for paper and pulp effluent treatment

A thesis submitted in fulfilment of the requirements f Master of Science in Engineering to the School of Chemical and Metallurgical Engineering, Faculty of Engineering, University of the Witwatersrand, Johannesburg, 2017Recently, the South African paper and pulp industry has become increasingly interested in the development of suitable wastewater treatment technologies able to assist in the closure of the water network and also to minimize their environmental footprint at their sites. Factors such as the rising cost of fresh water, stricter environmental legislation and socio-political pressure have forced water intensive users to become less dependent on the municipalities. The research described here addresses wastewater problems from two separate mills. Mill X (Case A) is relying on the municipality for fresh water and the treatment of their effluent. The mill wants to become less dependent on the municipality by closing the water network (zero effluent discharge). A wastewater treatment plant (WWTP) would be required to reduce the chemical oxygen demand (COD), total suspended solids (TSS) and colour before any processes water could be reused. Mill Y (Case B) is currently using their effluent for the irrigation of the local plantation. The mill would like a wastewater treatment plant able to reduce the biodegradable material prior to irrigation. Excessive amounts of biodegradable organics in the effluents can cause bacterial and fungal growth in the irrigations systems and consequently clogging problems. More advanced treatment steps would also be required to lower the bio-recalcitrant COD to environmental discharge limits (<400 mg/L). As a result, this study investigated the potential of combining biological and advanced oxidation processes (AOP) for effluent treatment at both mill effluents. An extensive literature study on the treatment of paper and pulp mill effluents was conducted to get a comprehensive understanding of the treatment technologies/combinations. The treatment of paper and pulp mill effluents can be divided into three distinct treatment stages namely: Primary treatment: For the removal of the total suspended solids (TSS) Secondary treatment: For the removal of the biochemical oxygen demand (BOD) Tertiary treatment: Mainly for the removal of bio-recalcitrant chemical oxygen demand (COD) and colour Mill X and Mill Y already contained primary clarifiers to remove the majority of the total suspended solids (TSS). Consequently, the secondary and tertiary treatment steps were evaluated. A detailed technology selection assessment was done to select the best suited secondary and tertiary treatment technologies for the purpose of this project. The work demonstrated that an aerobic MBBR could be used in combination with Fenton related treatment technologies in order to comply with the individual mill specifications. The applicability of both these biological and AOP treatment solutions was therefore extensively investigated. The results indicated that the aerobic moving bed biofilm reactor (MBBR) was able to remove the majority of the biodegradable organics from the recycle and neutral semisulfite chemical pulping mill effluents. The optimal COD removal efficiency ranged between 46% and 57% for the various effluents. The effluent from Mill X was generally found to be more readily biodegraded than the effluents from Mill Y. Experimental results indicated that certain effluents contain organics that display antimicrobial properties. The maximum substrate removal rate decreased linearly with an increase in phenols. As a result, it was therefore assumed that lignin derived alkyl phenols might have inhibited aerobic and anaerobic microbial digestion processes. The results indicate that the MBBR system was not fully acclimatized for high phenolic wastewaters. It is therefore recommended that future experimental studies consider the effects of phenolic content and employ longer acclimatization periods. A significant fraction of the paper and pulp mill effluents were considered to be bio-recalcitrant and required tertiary treatment to be removed. It was found that both the Fenton (Fe3+/H2O2) and Fenton-like (Fe3+/H2O2) oxidation processes can remove bio-recalcitrant organics from biologically treated mill effluents (BTME). However, preliminary experimental results indicated that the Fenton process had a faster oxidation rates. For the Fenton process, the optimal COD removal efficiencies ranged between 40% and 67% for the BTMEs. The experimental results also demonstrated that a combination of Fenton oxidation and slaked lime treatment can effectively remove the colour of BTMEs (97%). The COD removal rates for the neutral sulfite semi-chemical (NSSC) effluents were found to be higher than that of the recycle mill effluent (RME). The aromatic and volatile organic acid (VOA) content of the BTMEs had an important role in the oxidizing processes. The BTMEs with a higher volatile organic acid (VOA) content generally had slower oxidizing rates. The experimental results indicated that the combination of an aerobic MBBR and Fenton process can be implemented at both paper and pulp mills to assist with their individual treatment requirements. An economic study for Case A (Mill X) was also conducted. The data obtained throughout this study was linked to previous water optimization work done at the mill. The economic analysis demonstrated that the aerobic moving bed biofilm reactor (MBBR) and Fenton treatment combination could treat the recycle mill effluent for reuse in a cost-effective manner. The total capital investment cost of the treatment plant was estimated to be R28.5 million and the operational cost was found to be R12.21/m3 of wastewater. The implementation of this treatment solution on the water network could save the mill approximately R 1.25 million/year. The rising cost of fresh water and discharge might increase the economic feasibility of such a WWTP in the near future.XL201

Bioremediation and biovalorisation of olive-mill wastes

Olive-mill wastes are produced by the industry of olive oil production, which is a very important economic activity, particularly for Spain, Italy and Greece, leading to a large environmental problem of current concern in the Mediterranean basin. There is as yet no accepted treatment method for all the wastes generated during olive oil production, mainly due to technical and economical limitations but also the scattered nature of olive mills across the Mediterranean basin. The production of virgin olive oil is expanding worldwide, which will lead to even larger amounts of olive-mill waste, unless new treatment and valorisation technologies are devised. These are encouraged by the trend of current environmental policies, which favour protocols that include valorisation of the waste. This makes biological treatments of particular interest. Thus, research into different biodegradation options for olive-mill wastes and the development of new bioremediation technologies and/or strategies, as well as the valorisation of microbial biotechnology, are all currently needed. This review, whilst presenting a general overview, focus critically on the most significant recent advances in the various types of biological treatments, the bioremediation technology most commonly applied and the valorisation options, which together will form the pillar for future developments within this fiel

Preparation, Proximate Composition and Culinary Properties of Yellow Alkaline Noodles from Wheat and Raw/Pregelatinized Gadung (Dioscorea Hispida Dennst) Composite Flours

The steady increase of wheat flour price and noodle consumptions has driven researchers to find substitutes for wheat flour in the noodle making process. In this work, yellow alkaline noodles were prepared from composite flours comprising wheat and raw/pregelatinized gadung (Dioscorea hispida Dennst) flours. The purpose of this work was to investigate the effect of composite flour compositions on the cooking properties (cooking yield, cooking loss and swelling index) of yellow alkaline noodle. In addition, the sensory test and nutrition content of the yellow alkaline noodle were also evaluated for further recommendation. The experimental results showed that a good quality yellow alkaline noodle can be prepared from composite flour containing 20% w/w raw gadung flour. The cooking yield, cooking loss and swelling index of this noodle were 10.32 g, 1.20 and 2.30, respectively. Another good quality yellow alkaline noodle can be made from composite flour containing 40% w/w pregelatinized gadung flour. This noodle had cooking yield 8.93 g, cooking loss 1.20, and swelling index of 1.88. The sensory evaluation suggested that although the color, aroma and firmness of the noodles were significantly different (p ≤ 0.05) from wheat flour noodle, but their flavor remained closely similar. The nutrition content of the noodles also satisfied the Indonesian National Standard for noodle. Therefore, it can be concluded that wheat and raw/pregelatinized gadung composite flours can be used to manufacture yellow alkaline noodle with good quality and suitable for functional food

Development Of Solid State Fermentation System For Enzyme Production And Its Usage In A Pilot Scale Deinking Of Printed Waste Paper

The present work deals with the development of solid state fermenter for enzymes production and the development of a pilot scale of enzymatic deinking system. The newly developed solid state fermenter, was named FERMSOSTAT®, which was used for the production of cellulases and xylanase using a local isolate; Aspergillus niger USM AI 1. Kajian ini memberi tumpuan kepada pembangunan fermenter keadaan pepejal untuk penghasilan enzim dan pembangunan sistem penyahdakwatan secara enzimatik berskala rintis. Fermenter yang bam dibangunkan itu dikenali sebagai FERMSOSTAT®

The effect of environmental regulation on firm productivity: evidence from pulp and paper industry in China

The relationship between environmental regulation and firm productivity has been widely debated but inconsistencies in findings across different studies. Using detailed firm-level micro-data from 2000 to 2007, this paper employs difference-in-difference combined with matching based on entropy balancing method to explore the effect of environmental regulation on firm total factor productivity (TFP) in pulp and paper industry in China. Our main findings are as following: Firstly, stricter environmental regulation, as represented by the Wastewater Discharge Standards for Pulp and Paper Industry in Shandong province, increases firm TFP significantly. Moreover, the coefficients of interest are robust to multiple robustness checks. Secondly, dynamic effects estimates reveal that when faced with this phase-in environmental regulation, firms take the foreseeably increasing strictness into account from the very beginning and prefer to take one-step adjustment to reach full compliance. Thirdly, potential mechanism analysis finds that the positive effect mainly comes from the improvement of resource allocation efficiency within firms. Fourthly, the heterogeneity test indicates that the effect of environmental regulation on firm TFP is heterogeneous across firms with different sizes, ages, ownerships, capital intensity, and export status. Finally, this paper provides convincing and insightful evidence that environmental regulation has the potential to achieve the dual goals of environmental sustainability and economic growth and is thus of broader significance for understanding the enforcement of environmental regulation in developing countries