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Flexographic printing technology is an economical, productive, low maintenance and versatile technology. However, the removal of these inks by the traditional flotation process during paper recycling is not possible since they remain dissolved in the waters, making necessary the development of alternative methods. Recent studies have revealed the potential use of nanocellulose (NC) combined with a cationic polyacrylamide to remove flexographic inks from wastewater. The use of a natural polymer, such as chitosan, would be an important improvement of this treatment because NC and chitosan are the two most abundant natural polymers with interesting properties, such as non-toxicity and biodegradability. Therefore, in this study the decolorization of three flexographic inks (copper phthalocyanine blue, carbon black and diarylide yellow) by the sequential addition of cellulose nanofibers, produced from recycled paper, and chitosan has been evaluated. Results show that this eco-friendly approach has high potential for the removal of water-based inks with an almost 100% reduction of turbidity and ink from the wastewater. Moreover, the final sludge containing nanocellulose and inks could be used to reinforce the pulp of the middle layers of carton board, improving the mechanical properties of the product and reducing waste generation., Comunidad de Madrid (Spain), MINECO, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Extending the limits of paper recycling by increasing the number of recycling cycles results in decreased mechanical properties due to the irreversible hornification of cellulose fibers. This process alters the fiber structure and properties because of the repeated chemical and mechanical treatments that occur during wetting and drying. As a result, poor tensile strength is the main source of customer complaints to paper manufacturers. Cellulose nanofibers (CNF) from bleached eucalyptus and pine pulps were investigated as potential strength additives because of their proven contribution to interfiber bonding. These results were compared to the results obtained using different families of strength additives. The effects on the mechanical properties of recycled old corrugated containers were studied by measuring bursting, tensile, and short span compressive strength. Cellulose nanofibers and cationic polyacrylamide (cPAM) improved the mechanical strength properties when they were added at doses around 4 wt.%. A combination of CNF and cPAM was also tested. The effects of the combined additives were not as high as expected compared to the results achieved individually. The CNF from pine pulp resulted in the highest increase in bursting index when combined with cPAM, achieving an increase of over 93%. The combination of CNF from eucalyptus pulp and cPAM increased the bursting index over 60%., European Union (FP7), Economy and Competitiveness Ministry of Spain (MINECO), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The need to increase the recovery rates of recyclables from households, reducing at the same time the collection costs, has favored the spreading of commingled collection systems. This study presents a thorough analysis of the quality of a secondary source of recovered paper of a Spanish newsprint mill, imported from the United Kingdom, where these systems are widely practiced. The results show that the quality of recovered paper from commingled systems is very far from the quality obtained with selective systems: the unusable material content vary from 1% to 29% (11.9% on average) compared to less than 1%. Larger materials recovery facilities (MRF), less oversaturated and with advanced sorting techniques, have demonstrated to be able to render better qualities, the unusable material content varying from 0.3% to 16.6% (8.1% on average). However, the quality is still far from contamination levels typically found with selective systems, especially in terms of non-paper components. This fact limits significantly the use of this recovered paper for graphic paper production where the major potential for an extended use of recovered paper in papermaking lies. Furthermore, there is a discussion on the cost efficiency of these systems and how the legislation and private or public initiatives are affecting the spreading of these systems, especially in the United States and the United Kingdom., Comunidad de Madrid, TRUE, pub

Despite the extraordinary properties of nanocellulose (NC), as confirmed through two decades of exhaustive research, addressing an array of potential applications, the NC market is still far from reaching its full potential. Among the main causes is the lack of process-adapted measuring tools capable of characterizing NC, at acceptable speed and reliability, to meet the industrial demands in a cost-effective way. Therefore, reliable characterization methodologies of NC and new standards are of paramount importance in ensuring reproducible research results and quality control specifications for present and future NC products and applications. Furthermore, the successful industrial use of NC products depends on critical parameters that are still being identified and studied. This review paper aims to identify some of the current drawbacks and limitations in NC characterization that hinder their commercial deployment. Moreover, important challenges related to characterization and new opportunities for future research in this field are addressed., Ministerio de Economía y Competitividad, Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The dispersion degree of cellulose micro and nanofibrils (CMFs/CNFs) in water suspensions is key to understand and optimize their effectiveness in several applications. In this study, we proposed a method, based on gel point (Øg), to calculate both aspect ratio and dispersion degree. This methodology was validated through the morphological characterization of CMFs/CNFs by Transmission Electronic Microscopy. The influence of dispersion degree on the reinforcement of recycled cardboard has also been evaluated by stirring CMF/CNF suspensions at different speeds. Results show that as stirring speed increases, Øg decreased to a minimum value, in which the aspect ratio is maximum. Then, Øg increased again. Suspensions with lower Øg, in the intermediate region of agitation present very good dispersion behavior with an open and spongy network structure, in which nanofibril clusters are totally dispersed. Higher stirring speeds shorten the nanofibrils and the networks collapse. Results show that the dispersion of the nanocellulose at the minimum Øg before their addition to the pulp, produces higher mechanical properties, even higher than when CNFs and pulp are agitated together. This method allows for the determination of the CMF/CNF dispersion, to maximize their behavior as strength agents. This knowledge would be crucial to understand why some industrial trials did not give satisfactory results., Ministerio de Ciencia e Innovación (MICINN), Universidad Complutense de Madrid/Banco de Santander, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Reinforcing fibers have been widely used to improve physical and mechanical properties of cement-based materials. Most fiber reinforced composites (FRC) involve the use of a single type of fiber to improve cement properties, such as strength or ductility. To additionally improve other parameters, hybridization is required. Another key challenge, in the construction industry, is the implementation of green and sustainable strategies based on reducing raw materials consumption, designing novel structures with enhanced properties and low weight, and developing low environmental impact processes. Different recycled fibers have been used as raw materials to promote circular economy processes and new business opportunities in the cement-based sector. The valuable use of recycled fibers in hybrid FRC has already been proven and they improve both product quality and sustainability, but the generated knowledge is fragmented. This is the first review analyzing the use of recycled fibers in hybrid FRC and the hybridization effect on mechanical properties and workability of FRC. The paper compiles the best results and the optimal combinations of recycled fibers for hybrid FRC to identify key insights and gaps that may define future research to open new application fields for recycled hybrid FRC., Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Nanocelluloses (NC) increase mechanical and barrier paper properties allowing the use of paper in applications actually covered by other materials. Despite the exponential increase of information, NC have not been fully implemented in papermaking yet, due to the challenges of using NC. This paper provides a review of the main new findings and emerging possibilities in this field by focusing mainly on: (i) Decoupling the effects of NC on wet-end and paper properties by using synergies with retention aids, chemical modification, or filler preflocculation; (ii) challenges and solutions related to the incorporation of NC in the pulp suspension and its effects on barrier properties; and (iii) characterization needs of NC at an industrial scale. The paper also includes the market perspectives. It is concluded that to solve these challenges specific solutions are required for each paper product and process, being the wet-end optimization the key to decouple NC effects on drainage and paper properties. Furthermore, the effect of NC on recyclability must also be taken into account to reach a compromise solution. This review helps readers find upscale options for using NC in papermaking and identify further research needs within this field., Ministerio de Economía y Competitividad (MINECO), Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Cellulose and chitin are the most abundant polymeric materials in nature, capable of replacing conventional synthetic polymers. From them, cellulose nano/microfibers (CNFs/CMFs) and chitosan are obtained. Both polymers have been used separately in graft copolymerization but there are not many studies on the use of cellulose and chitosan together as copolymers and the reaction mechanism is unknown. In this work, the reaction mechanism to produce nano/microcellulose-graft-chitosan polymer has been studied. Recycled cellulose pulp was used, with and without a 2,2,6,6-tetramethylpiperidin-1-oxyl-radical (TEMPO)-mediated oxidation pretreatment, to produce CNFs and CMFs, respectively. For chitosan, a low-molecular weight product dissolved in an acetic acid solution was prepared. Grafted polymers were synthesized using a microwave digester. Results showed that TEMPO-mediated oxidation as the cellulose pretreatment is a key factor to obtain the grafted polymer CNF-g-CH. A reaction mechanism has been proposed where the amino group of chitosan attacks the carboxylic group of oxidized cellulose, since non-oxidized CMFs do not achieve the desired grafting. 13C NMR spectra, elemental analysis and SEM images validated the proposed mechanism. Finally, CNF-g-CH was used as a promising material to remove water-based inks and dyes from wastewater., Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid/Banco de Santander, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

El proyecto consiste en construir un prototipo de coche “Chem-E-Car” y constituir a la UCM como una de las primeras universidades españolas que participa en dicha competición internacional.

In the last few years an increasing high interest has been drawn to the potential use of agricultural waste as raw material to produce structural reinforcement fibers for building materials, due to environmental and economical aspects. Corn is the world's most produced cereal in terms of quantity, what entails the generation of large quantities of waste. Despite this fact, only a few research works concerned with the use of fibers from waste corn stalks in the production of fiber-cement have been published and there is a complete lack of data on the characterization of these fibers. The objective of this research is to study the feasibility of using fibers obtained from corn stalk as reinforcement fibers in the production of fiber-cement through new environmentally friendly cooking methods. This study encompasses the morphological characterization of the fibers and the study of the effects that the use of these fibers has on the flocculation, retention and drainage of the fiber-cement suspensions and on the mechanical and physical properties of the final product. The results obtained in the tests confirmed the high potential of the corn stalk as a source of fibers for the manufacture of a fiber-cement capable of meeting the requirements of demanding applications., Ministerio de Ciencia e Innovación (España), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Increasingly stringent environmental standards and market demands are forcing pulp and paper mills to minimize both their water usage and their effluent discharge. Higher rates of process water reuse in pulp and paper mills leads to increased amounts of dissolved and colloidal substances in the process water, which is a major factor limiting further closure of the water circuits. This study explores the use of different types of talcs as control agents for dissolved and colloidal material contained in white water from paper mills using recovered and coated paper as raw materials. It also identifies the kinds of talcs that can be used to control detrimental properties of the white water., Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The use of enzymes has been suggested as an environmentally-friendly alternative to complement conventional chemical deinking in the recycling of recovered paper. This study compares the use of carbohydrate hydrolases versus laccase-mediator system for deinking printed fibers from newspapers and magazines. For this purpose, two commercial enzyme preparations with endoglucanase and endoxylanase activities (Viscozyme Wheat from Aspergillus oryzae and Ultraflo L from Humicola insolens) and a commercial laccase NS51002 from Trametes villosa), the latter in the presence of synthetic or natural (lignin related) mediators, were evaluated. The enzymatic treatments were studied at laboratory scale, using a standard chemical deinking sequence consisting of pulping, alkaline deinking and peroxide bleaching stages. Then, handsheets were prepared and their brightness, residual ink concentration, and strength properties were measured. Among the different enzymatic treatments assayed, both carbohydrate hydrolases were found to deink the secondary fibers more efficiently. Brightness increased up to 3-4% ISO on newspaper fibers, being Ultraflo 20% more efficient in the ink removal. Up to 2.5% ISO brightness increase was obtained when magazine fibers were used, being Viscozyme 9% more efficient in the ink removal. As regards laccase-mediator system, alone or combined with carbohydrate hydrolases, it was ineffective deinking both newspaper and magazine fibers, resulting in pulps with worse brightness and residual ink concentration values. However, pulp deinking by laccase-mediator system was displayed when secondary fibers rich in lignin, i.e. printed cardboard, were used, obtaining up to 3% ISO brightness increase and lower residual ink concentrations., Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The recovery and utilization of recovered paper have increased over past decades all over the world due to economic, environmental, and social issues. However, it is well known that an extended recovered paper collection is detrimental to its quality, either by the exploitation of lower quality sources such as households, or the spreading of commingled systems instead of selective collection systems. The influence of these two factors was assessed by analyzing the quality of different recovered paper grades used as raw material in a mill located in Madrid (Spain) producing newsprint and light weight coated paper from recovered paper. Part 1 of the paper deals with the impact of increased collection rates on the quality of recovered paper and Part 2 with the use of commingled collection systems. Results of Part 1 show that increased collection rates have a large impact on the quality of the recovered paper. The quality, measured as total unusable material and moisture contents, had deteriorated very rapidly in only four years (2005-2008) as a consequence of increased collection rates. Collection rates increased in Spain from 58.5% to 68.6% during this period, resulting in more than 50% increase of total unusable material and 25% of moisture content. The downgrading of the quality of recovered paper is one of the major threats for extending the current limits of paper recycling. Therefore, future challenge is to increase its availability but maintaining its quality., Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Pitch deposition in the pulp or in different parts of the manufacturing system can lead to a decrease in the quality of the final paper produced and to manufacturing efficiency problems. Tackiness is the property of pitch which related to the deposit formation. One of the methods to control pitch deposition in the pulp and paper industry is the use of the talc. The talc acts primarily by a detackification mechanism and hence must be part of the deposit to control further deposition. The effectiveness of talc as control agent depends on its structural and surface characteristics, e.g. specific surface, surface energy, surface charge and ratio lypophilic/hydrophilic surface, being these related to its mineral composition and the thermal and surface treatments it has undergone. Five commercial talcs, corresponding to two groups of different mineralogical compositions, have been tested to determine their detackification capacity using the deposition tester developed by the Complutense University of Madrid. In this method, the quantification of the deposits is carried out by an image analysis (IA) of stainless steel collectors on which the deposit has formed. After IA a qualitative analysis to determine the deposit organic fraction is carried out by gas chromatography (CG) after deposit extraction. The detackification capacity is expressed as the reduction of the deposits formed on the collectors when the different talcs at several concentrations are added to the pulp suspensions. The results show that pitch detackiness by talc addition is related to talc concentration and surface properties of mineral, as for example chlorite proportion, surface area and surface treatment and to the adsorption capacity of pitch on talcs. The general conclusions are that the talc having the highest quantity of mineral talc presents the best detackification capability and that all talcs studied have an appreciable detackification reduction at low proportion of addition., Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The stickies content, both macrostickies and stickies extractable in a solvent, was determined for samples taken at short time intervals from deinking lines producing deinked pulp for newsprint production. The study was carried out at three mills on different continents, with each having a different source of recycled paper as raw material. The short-term variations in extractable stickies in the incoming raw material were quite extreme, with differences of 100% being seen within hours. Despite this, the final deinked pulp contained fewer sudden variations and with no correlation to the incoming stickies content. While the raw material appeared to affect the incoming stickies content, a well-optimised deinking line was able to buffer the raw material variability and the final stickies content was more dependent on the deinking process. This result was seen for the two mills examined for this phenomenon, despite a different raw material supply. Macrostickies were found to exhibit the same tendencies, although with smaller and less sudden variations. However, the variations of macrostickies and extractable stickies never correlated, even when both were measured for the same pulp fraction, thus confirming that solvent extraction is not an appropriate method for determination of macrostickies and is more a reflection of microstickies., Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

“This document is the Accepted Manuscript version of a Published Work that appeared in final form in Industrial & Engineering Chemistry Research, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/ie9018098 ", The stickies content, both macrostickies and stickies extractable in a solvent, was determined for samples taken at short time intervals from deinking lines, producing deinked pulp for newsprint production. The study was carried out at three mills on different continents, with each having a different source of recycled paper as raw material. The short-term variations in extractable stickies in the incoming raw material were quite extreme, with differences of 100% being seen within hours. Despite this, the final deinked pulp contained fewer sudden variations and had no correlation to the incoming stickies content. While the raw material appeared to affect the incoming stickies content, a well-optimized deinking line was able to buffer the raw material variability, and the final stickies content was more dependent on the deinking process. This result was seen for the two mills examined for this phenomenon, despite a different raw material supply. Macrostickies were found to exhibit the same tendencies, although with smaller and less sudden variations. However, the variations of macrostickies and extractable stickies never correlated, even when both were measured for the same pulp fraction, thus confirming that solvent extraction is not an appropriate method for the determination of macrostickies and is more a reflection of microstickies., Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Products at a high and constant level, for meeting the consumer demands. However, since paper recovery is increasing, the quality of recovered paper is decreasing and, what is even worse, it varies along the time. The physical properties of recycled pulp fibres have a strong influence on most of the paper properties and, therefore, they play an important role in the establishment of the optimal papermaking conditions. These properties are directly related to the morphology of fibres and to pulp composition. In recent years, several new fibre and pulp morphological analyzers have been developed and released on the market. The use of online optical fibre analyzers allows papermakers to know the variations in pulp quality, enabling them to adjust the process and to maintain constant the quality of the paper produced. However, most of these devices are optimized for virgin fibres, their application for recovered paper being still limited. The present paper describes the modifications carried out in the programs of a fibre and pulp morphological analyzer (Morfi V7.9.13.E) to optimize its performance for the characterization of recycled pulps. The three programs (VESSELS, FIBRES and SHIVES) that the device includes by default have been considered and validated in a paper mill, producing different grades of newsprint and light-weight coated papers. The results show that, with the modified program, the device appears as a very promising tool to control and improve the final quality of recycled paper., European Commission, Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

“This document is the Accepted Manuscript version of a Published Work that appeared in final form in Industrial & Engineering Chemistry Research, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/ie8011837", This paper presents the effect of the structure of cationic polyacrylamides (CPAMs) on flocculation of pulpsuspensions and floc properties. A focused beam reflectance measurement (FBRM) probe was used to monitor flocculation, deflocculation, and reflocculation processes in real time. To carry out the study, 1% elemental chlorine free (ECF) eucalyptus kraft pulp containing 20% ground calcium carbonate (GCC) was used. Results show that the effect of the CPAM structure depends on charge density and polymer dose. Floc size does not always decrease with branching degree, whereas floc stability and reflocculation ability increased when highly charged and branched CPAM was used. These findings indicate that the use of highly branched CPAMs with very high molecular weight is very promising as a retention aid method to improve the papermaking process., Comunidad de Madrid, European Commission, TRUE, pub

La versión definitiva online de este artículo está publicada en Waste Management, vol. 29, nº 1, pp. 293-308, 2009,doi:10.1016/j.wasman.2008.02.002 y disponible en www.elsevier.com, Eleven million tonnes of waste are produced yearly by the European pulp and paper industry, of which 70% originates from the production of deinked recycled paper. Wastes are very diverse in composition and consist of rejects, different types of sludges and ashes in mills having on-site incineration treatment. The production of pulp and paper from virgin pulp generates less waste but the waste has similar properties to waste from the production of deinked pulp, although with less inorganics. Due to legislation and increased taxes, landfills are quickly being eliminated as a final destination for wastes in Europe, and incineration with energy recovery is becoming the main waste recovery method. Other options such as pyrolysis, gasification, land spreading, composting and reuse as building material are being applied, although research is still needed for optimization of the processes. Due to the large volumes of waste generated, the high moisture content of the waste and the changing waste composition as a result of process conditions, recovery methods are usually expensive and their environmental impact is still uncertain. For this reason, it is necessary to continue research on different applications of wastes, while taking into account the environmental and economic factors of these waste treatments., Comunidad de Madrid, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Talc is used traditionally for pitch control in papermaking. The effectiveness of talcs as control agent of dissolved and colloidal pitch depends on its structural and surface characteristics of minerals. Talcs are modified by thermal and surface treatments to obtain different properties e.g specific surface, surface energy, surface charge and ratio lypophilic/hydrophilic surface. Five commercial talcs have been tested to determine its capacity to adsorb the lypophilic contaminants by experiments of adsorption isotherms. The talcs correspond to two groups of different mineralogical compositions: one with high concentration of talc and some dolomite; and the other, with medium concentrations of talc and chlorite. Colloidal dispersions of extractives were obtained by extraction of Eucalyptus globulus wood at pilot plant scale with acetone, evaporation of the solvent and reextraction with hexane to increase the selectivity of lypophillic compound extraction. The isotherms of adsorption of the pitch dispersions were carried out at 50ºC on the different talcs. The adsorption took place by a mechanism of colloidal adsorption and the results obtained were adjusted to the Langmuir equation. Results show that talc addition to bleaching waters or process waters can produce high reductions of colloidal pitch concentrations, at comparatively low doses., Ministerio de Ciencia e Innovación (España), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Due to trends in papermaking like closed water systems or higher use of recovered paper as raw material, a large number of contaminants are accumulated in the system as dissolved and colloidal material (DCM). When the DCM is destabilized by a sudden change in the system conditions, it produces sticky deposits called secondary stickies that affect the papermaking processes and the quality of the final product. The laboratory methods existing to predict DCM destabilisation have limitations as low reproducibility or they do not distinguish between sticky and non-sticky materials and/or high volumes are necessary to perform the test, etc. In order to solve these problems, a methodology to predict the depositability potential of DCM has been developed by the Complutense University of Madrid. The methodology is based, first, on the destabilisation of the DCM by polymer addition, second, on its deposition on the collector surfaces and, third, on the quantification of the formed deposits by image analysis. Results show that the methodology has a good reproducibility with an error below 10%. Validation was carried out by application of the method to different cases. Results demonstrate that the developed methodology is a useful tool for researchers and papermakers to predict deposit problems due to the destabilisation of DCM in papermaking., European Commission, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

La utilización de papel de recuperación como materia prima para la fabricación de papel reciclado presenta numerosas ventajas medioambientales y económicas. Sin embargo, también tien graves inconvenientes, debido a la cantidad de contaminantes que se introducen en el sistema. Los contaminantes que se encuentran en forma de materia disuelta y coloidal no pueden ser eliminados por los procesos mecánicos convencionales y cuando se desestabilizan, por un cambio brusco de las condiciones del sistema, son responsables directos de la formación de manchas y agujeros en el producto final. El objetivo de esta Tesis es el desarrollo de un procedimiento para determinar la tendencia de la materia disuelta y coloidal presente en un agua papelera a la formación de depósitos adherentes, de manera práctica y precisa. El método desarrollado consta de las etapas necesarias para la obtención de las aguas blancas, en condiciones similares a las que se obtienen en el proceso de fabricación de papel reciclado. Las aguas caracterizadas se desestabilizan con un polímero catiónico para favorecer la formación de depósitos utilizando un equipo de deposición diseñado para tal fin, denominado "Rotor de Deposición", que permite llevar a cabo la determinación cuantitativa de los depósitos mediante un sistema de análisis de imagen. Con el método desarrollado, una vez validado y determinada su reproducibilidad, se lleva a cabo un estudio en aguas blancas obtenidas a partir de suspensiones de pasta que contienen los contaminantes propios del proceso de reciclado de papel: adhesivos, compuestos de estucado y jabones de destintado. Se estudia el efecto que jercen distintas variables, como la naturaleza del contaminante, la presencia de aditivos de destintado, la naturaleza de los agentes de desestabilización, la dosis empleada y las características del medio (pH, conductividad y durez de las aguas), sobre la tendencia a la formación de depósitos adherentes. Así mismo, se lleva a cabo un estudio de la d