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A large amount of wool produced in the EU region is coarse and of low quality. The limited or nonutilization of such coarse wool leads to landfilling causing environmental pollution. In this paper, we studied the properties of keratin hydrolyzate, produced by a sustainable hydrolysis process, to be used as a foaming agent in foam dyeing of cotton and wool fabrics. This is a preliminary step on the way to find possible applications which overcome the environmental problem of wool waste and byproducts. We report for the first time the use of keratin hydrolyzate as a foaming auxiliary in the textile dyeing process. The surface tension, molecular weight, foam stability, blow ratio, and bubble size of keratin hydrolyzate in aqueous solutions with and without dyeing auxiliaries were determined. The dyeing influential parameter such as wet pickup was studied to identify their effect on dye fixation and color strength. The foam dyeing was compared with conventional cold-pad batch and pad-steam processes for cotton and wool, respectively. In the investigated variant, keratin hydrolyzate shows a reduction in surface tension, good foam stability along with dyeing auxiliaries, a blow ratio of about 10:1, and 0.02-0.1 mm diameter bubble sizes. These results make possible its application as a foaming agent. Cotton and wool fabrics were dyed using reactive and acid dyes respectively, on a horizontal padding mangle. In both cases, hydrolyzed keratin acts as a carrier for dye molecules and the mechanism of dyeing depends on the respective pH of the dye solution, keratin, and fiber. Foam dyeing of cotton resulted in comparable color strength, while wool shows higher color strength when compared with conventional dyeing processes. Washing and rubbing fastness of cotton and wool foam dyed fabrics are similar to the respective conventional dyed fabrics. The combinations of sustainable keratin hydrolyzate production and its use as an eco-friendly, biodegradable foaming agent in less add on foam dyeing technology resulted not only in saving of large amounts of water and energy but also will be helpful in minimizing a load on effluent and the environment.

The present work aims at investigating the residence time distribution (RTD) of a multiple spouted bed reactor, which will be applied for the pyrolysis and gasification of residual biomass. The unit is composed of square-based spouted beds, placed in series and at descending heights, and communicating with each other through an opening in the lateral wall. The gas is fed evenly in parallel. The experimental analysis is based on tracer experiments in cold-flow units, assessing the influence of the number of units and the bed height. The tests proved the good mixing properties of the spouted beds, which create a stable fluidization regime and do not feature dead zones. Each spouted bed can generally be well assimilated to an ideal continuous stirred tank reactor (CSTR). The RTD of the device seems adequate for the application, and also seems to be well tuneable through the selection of the bed height and number of units. Given the good similarity with ideal reactor networks, these represent a valid tool to estimate the final behavior in terms of RTD.

A noticeable amount of dyes may remain in the wastewater downstream of dyeing facilities giving anaesthetic colorations as well as environmental concern. Conventional biological treatment alone cannot guarantee a sufficient decolouration and tertiary treatments have to be necessarily considered. Two oxidation schemes by ozone were considered in this work. A bubble column reactor (as a benchmark, in agreement with industrial applications) and a recycle well-mixed reactor were compared to reach the highest decolouration of standard dyes. In addition, hydrodynamic and ultrasonic cavitation were considered in the recycled well-mixed reactor to intensify its performance. The decolouration analysis was carried out for two dye classes (reactive and disperse), characterized by very different physical and chemical features. It appeared that some benefit was brought by ultrasound cavitation in the case of disperse dye only, while the degradation of the reactive dye was not intensified by the above hydraulic phenomenon. Ozone treatment was protracted to obtain different decolouration degrees of wastewater generated by wool dyeing. The resulting water was tested as a recycled process fluid to prepare fresh dyeing liquors, where devising the minimum decolouration degree became one of the quality specifications for recycling water back to dyeing. This article is protected by copyright. All rights reserved

The purpose of this work was to present a methodology to assess the energy consumption, specifically the energy utilized in the washing and drying processes, of textile products in their use-phase with the help of statistical tools. Regardless of the environmental impacts associated with the use-phase of textile products, analysis of energy consumption in that phase is still lacking. There is a need to design methodology for identifying the hotspots and parameters influencing the energy consumption in the use-phase of textile products. A pragmatic method that consists of a life-cycle assessment (LCA) framework plus principle component analysis (PCA), extended by Procrustes analysis (PA), is used to determine the energy consumption and minimize the possible uncertainties in the use-phase of textile product systems. The LCA plus PCA-PA method employed in this work to analyze the energy consumption of textile products in the use-phase comprises two statistical tools. First, PCA was applied to find the key parameters affecting the results. As an extension of PCA, PA was performed to highlight the most prominent variables within the dataset and extract the maximum amount of information. Lastly, hierarchical cluster analysis (HCA) was utilized for the classification of textile products on the basis of energy consumption variables and the similarity of their results. Among various energy consuming parameters in the use-phase of a textile product, both geographical and physical aspects can be prominent variables that significantly can affect the results of the energy consumption. After the LCA plus PCA-PA methodology, country of the use-phase in the geographical aspect and in the physical aspect, the fiber type and weight of the products were the influential variables. Hotspots or influential parameters being identified, a number of steps can be taken that can play an important role in decreasing environmental impacts by reducing the energy consumption in the laundering process of textile products during the use-phase. The methodology of LCA plus PCA-PA for energy consumption in textile products was employed to study the gap in currently available assessments. Using this method, the main influencing energy consuming parameters or hotspots in the use-phase of a textile product system could easily be identified and potential improvements of sustainability can be proposed.

From experiments, the influence of the physical characteristics of different binary mixtures of solids on the spouting regime of a pyramidal square-based spouted bed reactor is assessed. The applied methodology permits a more precise evaluation of the effects of the tested variables (diameter, density, sphericity) on the response variables (minimum air flows at which spouting begins and at which to maintain spouting conditions). The associated pressure drops along the bed of particles and the height of the formed fountain are analysed in each case. During the initial stages of fluidisation, binary mixtures containing different density ratios show dead zones. Segregation becomes more evident at large-size and high-density ratios. The lack of sphericity was found to be the main reason leading to blocking, channelling, and start-up problems when system failures occur. Nevertheless, the extent of segregation in all cases decreases with increasing the spouting velocity. In addition, a computational fluid dynamic model based on the discrete element method, previously validated for a single solid bed, is proposed as a tool to predict and evaluate potential segregation phenomena in binary mixtures. This model reproduced with high accuracy the encountered segregation phenomena. Its use may help define the technical limits inherent in the pyramidal spouted bed reactor.

Keratin from wool fibers was extracted with different extraction methods, for example oxidation, reduction, sulfitolysis, and superheated water hydrolysis. Different samples of extracted keratin were characterized by molecular weight determination, FT-IR and NIR spectroscopy, amino acid analysis, and thermal behavior. While using oxidation, reduction, and sulfitolysis, only the cleavage of disulfide bonds takes place; keratin hydrolysis leads to the breaking of peptide bonds with the formation of low molecular weight proteins and peptides. In the FT-IR spectra of keratoses, the formation of cysteic acid appears, as well as the formation of Bunte salts (–S–SO3–) after the cleavage of disulfide bonds by sulfitolysis. The amino acid composition confirms the transformation of amino acid cystine, which is totally converted into cysteic acid following oxidative extraction and almost completely destroyed during superheated water hydrolysis. Thermal behavior shows that keratoses, which are characterized by stronger ionic interaction and higher molecular weight, are the most temperature stable keratin, while hydrolyzed wool shows a poor thermal stability.

The present study focuses on the use of N-methylformanilide as swelling agent in the dyeing process of meta-aramid fibers. Fiber dyeability with a cationic dye (C.I. Basic Blue 41) has been examined at three different N-methylformanilide concentrations: in particular, adsorption isotherms, dyeing kinetics and fastness to washing and rubbing have been investigated. The experiments have been carried out in a batch system to optimize initial dyestuff concentration, swelling agent concentration and dyeing time. Langmuir, Freundlich and Temkin adsorption isotherms have been used to model equilibrium data. It was found that Freundlich model agreed very well with experimental data: the correlation coefficients ranged from 0.97 to 0.99. The adsorption kinetics has been discussed in view of two kinetics models, i.e. the first-order Lagergren's model and a pseudo-second order model. The pseudo-first order kinetics model describes Basic Blue 41 adsorption on meta-aramid fiber very well. From the technological point of view, 5% on weight fiber (o.w.f.) of Basic Blue 41 and 60% o.w.f. of N-methylformanilide has been found to be adequate to obtain a deep and uniform hue. All dyeing conditions provide satisfactory fastness properties.

It is well established that current flame retardant (FR) products at disposal generate various ecological hazards. Irrespective of their environmental impacts, the FR market is growing and is estimated to reach 2.8 million tons globally in 2018. In the textile domain, FRs are incorporated into baby clothing, pushchairs, car seats, etc. When disposed, these FR textile products end up in a landfill or are incinerated. These disposal processes are unsustainable. With landfilling, there is a huge chance of the FR product leaching into the environment. Similarly, FRs decrease energetic yields in the incineration process due to incomplete combustion. To cope with such issues, degradation and elimination of the FR product from the textile products before disposal could be a sustainable alternative. This study dealt with the preliminary degradation of flame retardant from the cotton textiles and its thermal characterization. Energy valorization by gasification is considered beneficial opposed to incineration with overall low energy recovery. The initial optimum gasification conditions including FR-treated cotton as a feeding material and potential outcomes of FR-treated cotton after degradation were characterized.

The purpose of this work is to understand the impact of superheated water hydrolysis treatment on the chemical properties of wool, and compare it with a conventional method of alkaline hydrolysis. The effects of hydrolysis temperature and concentration of alkali on the properties of wool were investigated. Superheated water hydrolysis was carried out at the temperatures of 140℃ and 170℃, with a material to liquor ratio of 1:3 for 1 hour. In conventional alkaline hydrolysis, the experiments were carried out in the same conditions using potassium hydroxide (KOH) and calcium oxide (CaO) with a concentration in the range of 5%–15% on the fiber weight (o.w.f.). The effects of hydrolysis temperature and alkali concentrations on wool properties were checked using optical and scanning electron microscopy. It was observed that the hydrolyzates obtained in both cases contained low molecular weight proteins and amino acids. Both the hydrolysis processes resulted in degradation of the wool fibers. However, superheated steam hydrolysis is an environmentally friendly and less expensive process, as it is performed using water as a solvent. The wool hydrolyzates produced using superheated water hydrolysis could find a potential application in agriculture, such as fertilization, soil improvement and suchlike.

The present work aims to study the effect of the liquid temperature on the performance of ultrasounds (US) in a dyeing process. The approach was both theoretical and experimental. In the theoretical part the simplified model of a single bubble implosion is used to demonstrate that the "maximum implosion pressure" calculated with the well known Rayleigh-Plesset equation for a single bubble can be correlated with the cavitation intensity experimentally measured with an Ultrasonic Energy Meter (by PPB Megasonics). In particular the model was used to study the influence of the fluid temperature on the cavitation intensity. The "relative" theoretical data calculated from the implosion pressure were satisfactorily correlated with the experimental ones and evidence a zone, between 50 and 60°C, were the cavitation intensity is almost constant and still sufficiently high. Hence an experimental part of wool dyeing was carried out both to validate the previous results and to verify the dyeing quality at low temperatures (40-70°C) in presence of US. A prototype dyeing equipment able to treat textile samples with US system of 600W power, was used. The dyeing performances in the presence and absence of US were verified by measuring ΔE (colour variation), Re,% (reflectance percentage), K/S (colour strength) and colour fastness. The US tests performed in the temperature range of 40-70°C were compared with the conventional wool dyeing at 98°C. The obtained results show that a temperature close to 60°C should be chosen as the recommended US dyeing condition, being a compromise between the cavitation intensity and the kinetics which rules the dyestuff diffusion within the fibres.

Dyeing processes of various yarns (wool, cotton, polyester, nylon 6 and acrylic) were studied with the aim to substitute some auxiliary agents with ethanol at low concentration. The results observed in isothermal dyeing showed a favorable effect of alcohol addition, at about 1–3% v/v, on the dye uptake, with some differences depending on fiber nature and dye class. This effect was correlated with contact angle measurements of water-ethanol solutions on the mentioned yarns, which confirmed a lower surface tension in the same concentration range. Then, laboratory tests with dye triads at programmed temperature were carried out comparing the results of standard dyeing recipes with those obtained by replacing wetting, retardant and leveling agents with ethanol. Good color imitations were generally shown with respect to standard processes. A wetting effect of ethanol was shown for all the tested yarns and dye classes, while in wool dyeing with acid, pre-metallized and reactive dyes, ethanol was suitable to replace also leveling and retarding agents. Light and wash fastnesses were also compared. Finally the environmental benefits arising from chemical substitution of auxiliary agents with ethanol were highlighted and the cost of alcohol introduction was compared with the cost saving of auxiliary substitution. A positive economic balance was obtained.

Wastewater from textile industry usually undergoes activated sludge biotreatment ahead of refining treatments, final discharge or reuse. To identify the most effective bioreactor typology for the secondary treatment of a wastewater resulting from a textile industry of the Biella district (Italy), four pilot units characterized by a different configuration and fluid dynamics (i.e., Bioflotation®, Fixed Bed Biofilm Reactor (FBBR), flow-jet aeration and standard aerobic sludge reactors) were operated in parallel, inoculated with the same microbial consortium and fed with identical streams of wastewater discharged from wet textile processes of the industy. COD, TC and non-ionic surfactants were monitored in effluents of the compared bioreactors working under continuous mode and the cultivable heterotrophic microorganisms prevailing in each of them were isolated and characterized as the end of the study. The results demonstrated that the air supply system greatly influenced the treatment efficiency which reached the highest value in the case of Bioflotation® and FBBR technology. A highly specialized bacterial biomass mostly composed by strains of the Pseudomonas, Stenotrophomonas and Ochrobactrum genera was isolated in such reactors, thus suggesting that a direct correlation between reactor configuration, decontamination performances and microbial biomass composition exist.

An atmospheric pressure plasma jet (APPJ) for continuous treatment of polymeric films and textile materials was investigated to characterize its thermal, hydrodynamic and chemical features. The operative variables of the plasma jet equipment are: gas flow rate and composition, electrical power to the plasma generator and fabric velocity. A diagnostic evaluation of the equipment was carried out to improve the treatment homogeneity and generate an effective feedback for scale-up. The cross profile of gas temperature and velocity, the fabric temperature and concentration transitory in the gas system generated by a reverse step of oxygen were determined. These measurements showed that the original prototype configuration required a better gas distribution to fully demonstrate its potentiality to functionalize textiles. The surface modifications induced by plasma were detected by processing wool fabrics and by evaluating the treatment benefit on dyeing.

A large amount of coarse wool, practically unserviceable for textile use, is generated in Europe from sheep shearing and butchery. Such a byproduct is either dumped, burned, or sent to landfill. Following the European Commission regulations on animal byproduct control, unserviceable raw wool is classified as a category 3 special waste materials. The collection, storage, transport, treatment, use, and disposal of such unserviceable raw wool are subject to European Union regulations because of a potential risk to human and animal health. This study aims at converting the waste wool into nitrogen fertilizers at a commercial scale for grassland management and cultivation purposes. The chemical transformation of waste wool in to fertilizer is based on a green economically sustainable hydrolysis treatment using superheated water. The experiments were carried out in a semi-industrial reactor feeding superheated water. The wool/superheated water system was maintained for different reaction times. The optimal conditions for this treatment were as follows: 170 °C for 60 min with a solid to liquor ratio (MLR) close to 1. The hydrolyzed product was analyzed using amino acid analysis and molecular weight distribution. Both the amino acid and molecular weight distribution analysis revealed that the wool was completely degraded and the hydrolyzed product contains a low molecular weight proteins and amino acids. Several hydrolyzed product obtained at different conditions were tested for germination which showed a germination index higher than 100% without collateral phytotoxicity. The presence of amino acids, primary nutrients, and micronutrients in wool hydrolyzates, along with a concentration of heavy metals below the standard limit, confirm the possibility of using wool hydrolyzates as a nitrogen based ecologically sound fertilizer.

The infusion of high purity Factor VIII and Factor IX concentrates represent one of the best alternatives in the treatment of haemophilia A and haemophilia B respectively. Among the dehydration techniques, freeze-drying is considered as the reference process preserving biological activity and, consequently, it is utilised for manufacturing high-quality pharmaceutical products. The aim of this work was to study the influence of the freezing and the drying conditions on the final quality of both freeze-dried high purity Factor VIII and Factor IX concentrates. The biological activity of both Factor VIII and Factor IX was not influenced by the freezing rates and, considering the experimental conditions that led to uncollapsed products, by the drying rates studied. Moreover, according to other previous works and to the industrial experience, no remarkable difference on their biological activities depending on the freezing and primary drying conditions was noticed for both factors. From these results, a new optimised cycle that permitted to reduce considerably the duration of the freeze-drying process, was defined. The freeze-dried products obtained had a relative biological activity in line with the actual industrial standards, were good rehydratable and showed a stability of at least 1 month at +4 °C.

The effect of different lyoprotectants (sucrose, dimethyl-succinate buffer (DMS), bovine serum albumin (BSA), mannitol and dextran, mw 60 kDa) on the stability of the enzyme lignin peroxidase (LiP, EC number: 1.11.1.-), both during the freeze-drying process and storage were investigated. The shelf stability tests were performed at 4 °C and 27 °C. Both DMS buffer and sucrose showed a good protective action: the former was particularly effective during the process, while the latter improved the stability during storage. In contrast, mannitol and dextran had negative effects, reducing the activity also in the lignin peroxidase solution. BSA was discarded because, in the range of compatible concentrations with LiP, it does not confer a consistent structure to the freeze-dried product. © 2002 Society of Chemical Industry

A spouting bed reactor using rice straw as feedstock for further gasification purposes was studied in the present work. Experimental fluid dynamic tests were carried out in a conical square-based spouted bed reactor using a mixture of straw and silica, the latter acting as inert material. The influence of the initial bed of particles and the presence of coarse particles in the mixture on the pressure drop and minimum spouting velocity were evaluated. As a result, lower values of pressure drop along the bed were found compared to conventional fluidisation processes. Higher initial bed heights and higher percentage of straw in the mixture resulted in higher values of pressure drop and minimum spouting velocity. A new correlation for a cross section spouted bed reactor was proposed for the prediction of the minimum spouting velocity.

The [Formula: see text]-methylol dimethyl phosphono propionamide (MDPA) flame retardant compounds are predominantly used for cotton fabric treatments with trimethylol melamine (TMM) to obtain better crosslinking and enhanced flame retardant properties. Nevertheless, such treatments are associated with a toxic issue of cancer-causing formaldehyde release. An eco-friendly finishing was used to get formaldehyde-free fixation of flame retardant to the cotton fabric. Citric acid as a crosslinking agent along with the sodium hypophosphite as a catalyst in the treatment was utilized. The process parameters of the treatment were enhanced for optimized flame retardant properties, in addition, low mechanical loss to the fabric by response surface methodology using Box–Behnken statistical design experiment methodology was achieved. The effects of concentrations on the fabric’s properties (flame retardancy and mechanical properties) were evaluated. The regression equations for the prediction of concentrations and mechanical properties of the fabric were also obtained for the eco-friendly treatment. The R-squared values of all the responses were above 0.95 for the reagents used, indicating the degree of relationship between the predicted values by the Box–Behnken design and the actual experimental results. It was also found that the concentration parameters (crosslinking reagents and catalysts) in the treatment formulation have a prime role in the overall performance of flame retardant cotton fabrics.

Wet textile washing processes were set up for wool and cotton fabrics to evaluate the potential of ultrasound transducers (US) in improving dirt removal. The samples were contaminated with an emulsion of carbon soot in vegetable oil and aged for three hours in fan oven. Before washing, the fabrics were soaked for 3 min in a standard detergent solution and subsequently washed in a water bath. The dirt removal was evaluated through colorimetric measurements. The total color differences ΔE of the samples were measured with respect to an uncontaminated fabric, before and after each washing cycle. The percentage of ΔE variation obtained was calculated and correlated to the dirt removal. The results showed that the US transducers enhanced the dirt removal and temperature was the parameter most influencing the US efficiency on the cleaning process. Better results were obtained at a lower process temperature.

Flow regimes in gas–solid fluidisation are presented on a broad scale from captive smooth fluidisation to dilute transport. The parameters useful to identify each transition are critically presented. The description of catalytic gas–solid fluidised beds is considered starting from simplified two-phase models; a third phase given by clouds and wakes is then introduced to justify their effect in promoting solids circulation. Different hydrodynamic features have been used in the literature to describe the dense and the dilute phase, according to the mixing effect of bubbles. Circulating fluidised bed modelling is approached according to the definition of a hydrodynamic regime. The numerous models appearing up to now in literature are presented, from earlier homogeneous models to the latest continuous radial profile and clustering models. The development of spouted beds as chemical reactors is given from the first fundamental approach, followed by the experimentation in the late 1970s, ending with more complex descriptions that take into account all the spouted bed zones. A concluding chapter on model selection offers general criteria to tackle the mathematical description which predicts the performance of catalytic reactors in the different regimes.

Spouted beds appear to go through a revival, testified by a very recent and comprehensive book on the topic (Epstein & Grace, 2011). This renewed interest arises by implementing new concepts in scaling-up spouting contactors and devising potential applications to high temperature processes, noticeable examples being given by pyrolysis and gasification of biomass, kinetically controlled drying of moist seeds to guarantee the requested qualities and polymer upgrading processes.

In an earlier review on modeling of catalytic gas–solid fluidized bed reactors, spouted beds were treated as a special case of fluidized beds, with the jet region extending to the upper free surface of the solids emulsion. The spout and the annulus are two well-distinguished zones, characterized by such different gas–solid contacting that they have been treated distinctly since the first approach for modeling spouted bed chemical reactors. The spout zone acts as a dilute vertical transport system, whereas the peripheral annulus has many similarities with a countercurrent downflow packed bed, the major peculiarity being gas percolation into the dense emulsion from the spout. Therefore, solids motion in a spouted bed is a major factor affecting mass and heat transfer, mixing, contacting, and hence the choice of reactor model. The solids can react (e.g., in combustion, where they are depleted over time), constitute inerts (e.g., sand diluting a solid fuel and regulating the system hydrodynamics, as well as providing a heat buffer), or act as a catalyst. Successful design and operation of a reactor depend on the ability to predict the system behavior, especially the hydrodynamics, mixing of individual phases, heat and mass transfer rates, and kinetics of the reactions involved.

This work concerns the study of some important physical and mechanical properties of a wool fabric treated with a roll-to-roll atmospheric plasma jet equipment. The plasma pilot unit, based on a post-discharge technology, was equipped with an innovative plasma-to-fabric contactor, which promotes a relevant penetration of plasma through the fabric structure and geometrically defines the atmosphere. Wool fabrics were processed at three different velocities (1.3 and 6 m/min); the other process variables were kept constant. Tensile strength, elongation at break, surface thickness, wettability and air permeability increased after the plasma treatment, while several low-stress mechanical properties, strictly related to the handle, were not modified. SEM analysis was also carried out to better interpret the above macroscopic results. (C) 2009 Elsevier B.V. All rights reserved.

This paper presents the results from an extensive experimentation on polyester chips heating, crystallization and upgrading in three different size spouted bed units: a cylindrical 0.15 m diameter × 1.3 m tall, a 0.35 m square-based × 2.1 m tall parallelepiped and a sextuple multi-spouting 0.7 × 1.05 m2 demonstration reactor for solid state post-polymerization. The first apparatus was finalized to measuring several process operating variables (maximum gas temperature at the inlet, overall heat transfer coefficient and particle agglomeration tendency); the second unit provided the hydrodynamical data necessary to scale-up the system, insert into a PET upgrading process of 30 ton/day operating capacity and partially replace a bubbling fluidized bed heating/crystallizing unit. The ultimate goal of the project consisted in intensifying the process design by saving gas compression and thermal energy. The hydrodynamical findings of the squared modular unit were compared against several existing correlations: Manurung's equations for the maximum pressure drop and the pressure drop at stable spouting required a minimal alteration; Mathur and Gishler's equation properly fitted the experimental minimum spouting velocity. The continuously operating multiple spouting apparatus showed that regulating the solids level was an issue mainly due to the very large particle throughput, if related to the mixing efficiency of each module; reciprocal interference between spouted bed cells was manifested

A continuous autothermal two-stage pyrolysis/partial combustion process has been tested at the bench scale. Coal (or oil shale) up to 5 kg/h is fed to a spouted bed pyrolyzer in which the volatiles are driven off for tar recovery. Part of the resulting char is passed to a spouted bed partial combustor which produces the hot flue gas to provide heat and a spouting medium in the pyrolyzer. The two reactors are placed in a compact vertical configuration. The process is tested on two coals of different rank, and on oil shale. The effect of prime operating variables on yield are established and a number of operating modes demonstrated.

An apparatus to dry aqueous dispersions of solid lipid nanoparticles (SLNs) was designed. Optimal running conditions were evaluated to obtain minimum process time and produce dried SLNs characterized by small size variation. To achieve process optimization, SLN average diameter, SLNs polydispersity index, and drying time were related to three operative variables: process temperature, SLN concentration in the original aqueous dispersions, and nitrogen flow rate as the physical means of the drying process. An experimental design procedure and a multicriteria optimization method, targeting desirability functions, enabled us to obtain the optimal conditions for all responses. Drying time, average diameter, and polydispersity index of dried SLN batches were more favorable than those obtained by freeze-drying identical SLN aqueous dispersions with the same initial nanoparticle concentration.

Solid lipid nanoparticles (SLNs) have been proposed as alternative colloidal drug carriers. SLNs are obtained by dispersing warm oil-in-water microemulsions into cold water. The aim of this research was to investigate an evaporative drying process for aqueous dispersions of SLNs. For this purpose, a special apparatus, namely a thermostatic minidesiccator having alumina as the drying medium, was designed to carry out the evaporative drying at a controlled temperature. Besides the water removal kinetics, the mean particle size and the size distribution of SLNs were measured during the during with the aim of detecting the highest temperature at which the drying process can be carried out without significantly affecting the SLN average diameter. The SLN dispersions were evaluated with and without a hydrophilic excipient, commonly used as a cryoprotector (trehalose). The drying temperature of 10 degrees C was found to be the most suitable for obtaining SLNs as a powder, maintaining almost the same size as that of the SLNs in dispersion.

A capacitive balance that is able to work in the severe environment of a freeze-drying process has been conceived, constructed and tested. The influence of temperature variations had to be taken into account: a model of the instrument which makes use of the temperature of several components measured by three thermocouples was developed to correct the frequency signal generated by the device and to convert it into mass; the model parameters were identified by a least-squares method from blank lyophilisation runs. This balance offers the possibility of optimising the freeze-drying process through the accurate investigation of the process kinetics.

Freeze-drying is the process whereby a solvent (usually water) is removed from a frozen solution or a frozen foodstuff by sublimation. Since freeze-dry In this study, the lyophilization process was carried out on a frozen solution of cloxacillin monosodium salt using a pilot plant. Experimental drying A physical model is proposed for heat transfer between the heating plate and the tray containing the product, based on Knudsen conduction in a thin lay

A plain-weave wool fabric has been treated in a roll-to-roll atmospheric pressure, post-discharge plasma equipment at three fabric speeds. The thermal properties of the treated fabric have been investigated by means of an Alambeta instrument. The thermal resistance and thermal diffusivity increased after the plasma treatment while the thermal absorptivity and volumetric heat capacity decreased. The longer the plasma-to-fabric exposure time, the more marked the change in the fabric's thermal properties. Since thermal conductivity was unaffected after the treatment, the thermal properties changed due to the increase in thickness that was observed after the plasma treatment. A validated model has been used to predict the human psychophysical perception of the fabric hand. As a consequence of the more voluminous structure, a softer and warmer hand has been predicted for the treated fabrics compared to the untreated ones.

Hydrodynamic parameters were evaluated in a laboratory scale apparatus in order to provide data for CFBR (Circulating Fluidized Bed Reactor) design. Pressure drop and hold-up axial profiles were measured in a wide range of conditions with particular emphasis paid to dilute phase conveying where a pseudo-homogeneous flow is established in most of the upper part of the reactor. A safe correlation between pressure drop and solids hold-up is the link which permits a prompt evaluation of the reactor performance after exponential fitting of the pressure gradient along the axial direction. Ozone decomposition was chosen a as tracing reaction; comparison between measured and predicted conversion values was the ultimate goal of the present study aimed at demonstrating a possible approach for reactor design from gross parameter measurements.

Selectivity and yield in complex reactions were calculated for CFBRs with reference to industrial processes; the effect of longitudinal dispersion, catalyst effectivness, heat dissipation and co-reactant axial distribution were also considered. Two mathematical models with and without longitudinal dispersion provided the theoretical results to be compared with experiments.

Previously reported experimental work on the decomposition of ozone in a 0.15 m diameter spouted bed of angular iron oxide catalyst particles has been extended to spherical catalyst particles in both 0.15 m and 0.22 m dia. columns. Other variables, aside from column diameter, included catalyst particle size, bed depth, spouting velocity, and reaction rate constant (varied by adjusting the bed temperature). The use of a photometric analyser allowed analysis of concentrations at the inlet and exit from the bed, at different radial positions at the bed surface, and at several positions within the bed itself. Very little effect of particle size was found over the range studied (2.58 to 4.38 mm). Contrary to previous expectations, the conversion was found to decrease as the bed diameter was increased. The concentration gradients observed in the annulus indicate that the streamtube model is superior to the one-dimensional model, despite the fact that overall conversions predicted by these previously derived models are again similar. The observed gradients were not, however, as pronounced as those predicted by the streamtube model, and this suggests that radial dispersion in the annulus cannot be entirely neglected.

Segregation of solid materials, differing in density, was detected at the surface of the annulus of a spouted bed when a baffle, preventing mixing with solids from the fountain, was placed above an overflow pipe. Concentrations higher than 90% by volume in the light material could be obtained in the continuous discharge stream from a well mixed bed having an overall light-solids concentration as low as 3%. The gas velocity in the annulus, exceeding the minimum fluidization velocity of the light component, was shown to be the mechanistic explanation of the phenomenon. On a decele une segregation de matieres solides de densites differentes au sommet de l'anneau d'un lit “spoute”, lorsqu'on place une chicane qui empche le melange avec des matieres solides provenant de la fontaine, au-dessus d'un tuyau de trop-plein. On a pu obtenir, pour le materiau leger, des concentrations excedant 90% en volume, dans le courant continu de decharge a partir d'un lit bien melange, dont la concentration globale des matieres solides legeres etait aussi faible que 3%. On montre que le fait que la vitesse du gaz dans l'anneau excede la vitesse minimale de fluidisation est une explication mecanistique du phenomene.

The cause of segregation at the discharge in a continuously operating spouted bed has been investigated. Radial concentration profiles of the coarse component have been detected in a two-component mixture of glass ballotini at different spouting regimes, at different bed levels and discharging from openings at several bed depths. The annulus of a spouted bed has been shown to move in a fashion close to a plug flow without altering the concentration gradients existing below the bed free surface. Consistent with previous results, percolation induced segregation was negligible under these experimental conditions. The concentration existing at the column wall has been shown to be identical to that in the outgoing stream of solids and segregation phenomena at the outlet cannot explain a discharge composition different from the mean concentration in the bed. The particle trajectories in the fountain are believed to be responsible for the radial concentration gradient in the annulus of the spouted bed.

The residence time distribution function (RTDF) of a gas was measured in a gas—liquid stirred contactor with coalescing and non-coalescing systems using a gaseous tracer. It was found that the influence of the tracer solubility, even for a compound of very low solubility, was an important parameter which caused very long tails to the response curves. A methodology for the accurate evaluation of this effect was developed. The experimental results show that part of the gas moves in a plug-flow manner, this part depending on the gas—liquid hydrodynamic regime; the data can be satisfactorily interpreted by using a model which considers the partial recycling of the gas phase in the stirrer zone.

Spouted beds are an established way of coating nuclear fuel microspheres with pyrolytic carbon or silicon carbide by high-temperature thermochemical reactions. In recent years, similar coatings have aroused particular interest as bio-compatible materials. This paper describes the differences between these two applications, and the changes that must be made to the coating process and furnace to control both the overall surface of the bed material and its increase in volume. It is shown that a satisfactory control can be achieved by continuous feeding of small particles, followed by the continuous withdrawal of variously coated particles. Experiments on two columns with internal diameter of 0.08 and 0.14 m, respectively, showed that segregation phenomena may occur, depending on the flow dynamics, and that the way in which a steady state is brought about will depend on the position of the discharge pipe in the bed. Les lits “spoutes” constituent un moyen courant pour recouvrir des microspheres de combustible nucleaire de carbone pyrolytique ou de carbure de silicum, en employant des reactions thermochimiques a temperature elevee. Durant les dernieres annees, les recouvrements du type precite ont suscite un interět particulier en raison de leur biocompatibilite.

A detailed comparative analysis was carried out on freeze-drying coupled with an evaporative freezing and a conventional freezing step, using on-line monitoring of several fruit and vegetable weights vs. time. The experimental work was based on the use of two weighing cells: a traditional one and a prototype capacitive balance. The work showed that process rates differed because of product texture, water and sugar content, cooling temperature and freezing velocity. Different water release mechanisms were identified.

A continuous gelation process for producing aluminum and zirconium hydroxide microparticles was conceived and tested in a lab-scale apparatus. Fluidized state was devised as an appropriate hydrodynamic configuration to maintain the reacting sol microdrops suspended: stable non-coalescing spherical gel particles in a size range quite below 100 μm were produced via gelation. The microspheres produced by a subsequent calcination step showed a diameter ranging between 2 μm and 20 μm. This powder, without further size classification, was an optimal product to manufacture test specimens by sintering. Measurements on the mechanical properties, such as toughness, flexural strength and hardness, classified the test bars as a very promising ceramic material. In order to enlighten the chemical drying phenomenon and devise the main governing mechanisms acting in the gelation reaction, an extremely simplified experimental system was set. A single drop of sol was deposited into a given amount of the dehydrating liquid medium and observed by an optical microscope; image analysis permitted us to identify the gel formation, the size reduction kinetics, as well as secondary phenomena.

Production, consumption, and disposal of textile products have substantial adverse impacts on the environment, especially textiles with flame retardant (FR) finishes. Unfortunately, information on the exposure of FR from textile products to environmental pathways is scarce. Research works on FR textiles have been mostly focused on ways to provide environmentally friendly synthesis and production phases of FR textile products. However, the end-of-life phase of the FR textiles seems neglected and needs great attention when the product’s life cycle is concerned. The end-of-life phase of FR textile products is considered as a hurdle in current sustainable disposals (landfill and incineration), though today, technologies for solid waste management are ever-improving. Indeed, landfill and energy valorization through incineration are considered as suitable pathways for textile wastes, including technical textile wastes. However, the end-of-life of FR textile products creates issues, such as in landfilling, there is a huge chance of FR species or substance leaching to the environment. Similarly, FR species decrease energy yield in the incineration process due to incomplete combustion and emits toxic fumes.It is essential to find different ways to assess the most optimum methods or eco-designs for the disposal of textile products by energy valorization through gasification. Therefore an eco-design was proposed with optimized disposals for the FR textiles. Eco-design comprises the degradation and elimination of a permanent/durable FR substance from the textiles, especially cellulosic textiles prior to their disposals. Thermal valorization was achieved by gasification instead of incineration, to explore the ability of FRs to gasify after the degradation and elimination of the FR species.Durable FR species, for instance, n-methylol dimethyl phosphonopropionamide (MDPA) is one of the most effective organophosphorus FRs for cellulosic fabrics, used in combination with trimethylol melamine (TMM) to obtain durable and improved FR properties. The degradation and elimination of an organophosphorus FR (MDPA) on cellulosic fabric, was studied using an advanced oxidation process (AOP) based on Fenton’s reaction. The effect of varying concentrations of Fenton’s reagents (H2O2 and Fe2+ in aqueous medium) on the degradation of the MDPA was studied. The degradation of MDPA in aqueous media was monitored by measuring chemical oxygen demand (COD) of the reaction mixture over time. The mechanical properties of the cellulosic fabric after Fenton’s reaction were unaltered in both warp and weft directions. The flammability test and thermogravimetric results (TGA, DTG and PCFC) confirmed the degradation of MDPA FR from the fabric.FR species being degraded and eliminated from the cotton textiles, energy valorization by gasification was carried out for increased energetic yield due to better combustion and potential syngas composition outcomes during the gasification. The gasification results supported the eco-design by showing increased combustion properties of the FR textiles after the degradation and elimination of the FR species. For the sustainability validation of the proposed eco-design, a life cycle assessment (LCA) was performed to analyze the environmental impacts of eco-design for the end-of-life phase of FR textile products. LCA is one of the prominent assessment methods to perform the general assessment of products or services.The thermogravimetric and pyrolysis combustion results confirm that there is a higher heat release after Fenton’s reaction degradation. The heat release rate of the FR cotton textiles increased by 51% after the degradation of the FR species, and this makes the degraded FR cotton interesting for energy valorization. The energy valorization by gasification results supported the eco-design by showing increased combustion properties of the FR textiles after the degradation and elimination of the FR species. Lastly, the LCA results showed reduced impact values in most of the impact categories studied, especially in global warming potential (GWP), air acidification (AA) and in other prominent categories in favor of degradation and elimination of FR species from the textiles and being gasified., Les différentes phases du cycle de vie d’un produit textile, la production, l’utilisation et la fin de vie, ont des impacts importants sur l'environnement, en particulier lorsque les textiles ont été ignifugés. Malheureusement, lesdonnées concernant les produits ignifuges et leur présence dans l’environnement ne sont pas facilement accessibles. Dans le domaine des produits ignifuges utilisés pour le textile, les nombreuses recherches menées ont été principalement axées sur des méthodes de synthèse et de production de ces molécules afin de les rendre plus respectueuses de l'environnement. Cependant la phase de fin de vie des textiles ignifugés a été longtemps négligée, et nécessite aujourd’hui une attention particulière lorsqu’on effectue une analyse de cycle de vie d’un produit textile. Bien qu’aujourd’hui, les technologies utilisées pour la gestion des déchets solides ne cessent de s'améliorer, la valorisation des déchets par incinération est une voie appropriée pour les textiles, y compris les textiles techniques.La fin de vie des produits textiles ignifuges pose des problèmes. Lors de la mise en décharge, il existe de nombreuses possibilités de lixiviation des substances ignifuges dans l'environnement. De même, les espèces ignifuges diminuent le rendement énergétique dans le processus d'incinération en raison d'une combustion incomplète et émettent des fumées toxiques.Il est essentiel de trouver des méthodes optimales écologiques pour la valorisation énergétique des déchets textiles par la gazéification. Nous proposons une méthode plus écologique de valorisation énergétique des déchets textiles ignifugés, par la dégradation et l'élimination préalable des substances ignifuges permanentes des textiles, en particulier des cellulosiques. Ensuite, la valorisation thermique est réalisée par gazéification au lieu de l'incinération. Au bilan, nous discutons la capacité des tissus ignifugés à gazéifier et produire de l’énergie selon les prétraitements effectués. Le n-méthylol diméthylphosphonopropionamide (MDPA) est un des retardateurs de flamme organophosphorés le plus efficace pour les tissus cellulosiques, utilisés en combinaison avec la mélamine triméthylolique (TMM) pour obtenir des propriétés ignifuges permanentes et améliorées. La dégradation et l'élimination du retardateur de flamme organophosphoré (MDPA) sur le tissu cellulosique ont été étudiées à l'aide d'un procédé d'oxydation avancé (AOP) basé sur la réaction de Fenton. La cinétique de dégradation de la MDPA dépend des concentrations en réactifs de Fenton (H2O2 et Fe2+ en milieu aqueux). Elle a été suivie en mesurant la demande chimique en oxygène (DCO) du mélange réactionnel. Dans les conditions optimales de dégradation, les propriétés mécaniques du tissu cellulosique après la réaction de Fenton restent inchangées dans le sens chaîne et de la trame du textile tissé. Le test d'inflammabilité et les résultats thermogravimétriques (TGA, DTG et PCFC) confirment la dégradation du retardateur de flamme MDPA du tissu.Les espèces ignifuges étant dégradées et éliminées des textiles de coton, la valorisation énergétique par gazéification peut être effectuée pour augmenter le rendement énergétique en raison d'une meilleure combustion, mais aussi à cause de la composition du gaz de synthèse pendant la gazéification. Les résultats de gazéification montrent des propriétés de combustion accrues des textiles ignifuges après la dégradation et l'élimination des espèces ignifuges, qui permettent donc d’éco-concevoir la valorisation énergétique de ces textiles. Pour confirmer et valider cette méthode écologique, une analyse de cycle de vie (ACV) a été réalisée pour analyser et évaluer les impacts environnementaux réels de cette nouvelle méthode de fin de vie des produits textiles ignifugés. L’ACV est l'une des principales méthodes d'évaluation pour effectuer l'évaluation environnementale des produits ou des services.Les résultats de la combustion thermogravimétrique et de la pyrolyse confirment qu'il y a une libération de chaleur plus élevée après la dégradation de la réaction de Fenton. La libération de chaleur des textiles ignifugés de coton est augmentée de 51% après la dégradation des espèces ignifuges, ce qui rend le coton ignifuge dégradé intéressant pour la valorisation énergétique. La valorisation de l'énergie par des résultats de gazéification confirme qu’il y a bien une éco-conception en montrant des propriétés de combustion accrues des textiles ignifuges après la dégradation et l'élimination des espèces ignifuges. Enfin, les résultats de l'ACV ont montré des valeurs d'impact réduites dans la plupart des catégories d'impact étudiées, en particulier dans le potentiel de réchauffement planétaire (GWP), l'acidification de l'air (AA) et dans d'autres catégories importantes en faveur de la dégradation et de l'élimination des espèces ignifuges des textiles assujettis à la gazéification.

The efficiency of the untreated and TiO2 modified four gray cotton woven fabric samples and three white polyester samples, with different construction characteristics, before and after natural weathering were evaluated by measuring UV permeability trough the shade materials, tensile strength, water-repellency, oil- repellency and fabrics appearance by colour change assessment. The analysis of breaking force of the examined fabrics shows by cotton fibres no significant changes after weathering, and by polyester fabrics that TiO2 used partially decreasing the fibres photo-degradation. The results obtained indicate considerable increasing of brightness and UV protective properties of all undyed fabric samples modified with TiO2 nanoparticles and excellent fastness to weathering as well. All cotton fabrics treated with TiO2 incorporated in fluorocarbon finish have got an excellent water- and oil- repellency, which is slightly reduced after weathering.