744 resultados para textile
Resumo:
Effluent color resulting from textile dyeing processes has been one of the biggest environmental problems faced by the textile industry. In particular, reactive dyes are highly resistant to conventional wastewater treatment methods. New technologies have been contemplated, some of which have been applied in industrial treatment plants, but color removal has not been efficiently attained. Since microemulsion systems provide good results in heavy metals and proteins extraction processes, their use in dyes extraction has been suggested and investigated. In this work, a real textile wastewater from an exhaustion dyebath has been treated, which contains the following reactive dyes: Procion Yellow H-E4R (CI Reactive Yellow 84), Procion Blue H-ERD (CI Reactive Blue 160) and Procion Red H-E3B (CI Reactive Red 120), in addition to auxiliary compounds normally found in dyeing processes with reactive dyes. The dyes Remazol Blue RR and Remazol Turquoise Blue G (Reactive Blue 21) have also been examined in view of the presence of heavy metals in these molecules. The microemulsion system comprised dodecyl ammonium chloride (as a cationic surfactant), water or wastewater as aqueous phase, kerosene as oil phase, and one of the following alcohols as cosurfactant: isoamyl alcohol, n-butyl alcohol and n-octyl alcohol. The pseudo-ternary diagrams were constructed in order to define Winsor s equilibrium regions. The influence of parameters such as pH, C/S (cosurfactant/surfactant) ratio, distribution coefficient, initial dye concentration, salinity, temperature, phases relative amounts, loading capacity of the microemulsion phase and dye reextraction rate has also been investigated. An experimental planning (Scheffé Net) was used to optimize the extraction process. The removal of color and metals reached levels as high as 99%
Resumo:
Este artigo avalia os resultados do processo de reestruturação da indústria brasileira de máquinas têxteis, originado pelas reformas econômicas liberalizantes iniciadas no final dos anos 1980 e início dos 1990 e pelas medidas macroeconômicas que deram sustentação ao Plano Real, a partir de julho de 1994. Inicialmente, fazemos uma avaliação teórica das fontes do conhecimento e das formas de capacitação tecnológica nessa indústria. A seguir, expomos brevemente as principais características da indústria de máquinas têxteis em âmbito global. Posteriormente, direcionando a discussão para o caso brasileiro, apresentamos as especificidades da indústria têxtil, usuária daqueles bens, e do próprio setor de máquinas nacional. Através dos fluxos de comércio exterior do Brasil entre 1990 e 2004 e da variação do valor médio (US$ FOB/KG) desses fluxos, o artigo examina as mudanças estruturais, tecnológicas e, por conseguinte, na competitividade, que culminaram na transformação da indústria brasileira de máquinas têxteis, em termos de dimensão (escala) e escopo, e em uma nova inserção internacional, agora mais especializada e subordinada.
Resumo:
This study aims to assess the potential for industrial reuse of textile wastewater, after passing through a physical and chemical pretreatment, into denim washing wet processing operations in an industrial textile laundry, with no need for complementary treatments and dilutions. The methodology and evaluation of the proposed tests were based on the production techniques used in the company and upgraded for the experiments tested. The characterization of the treated effluent for 16 selected parameters and the development of a monitoring able to tailor the treated effluent for final disposal in accordance with current legislation was essential for the initiation of testing for reuse. The parameters color, turbidity, SS and pH used were satisfactory as control variables and presents simple determination methods. The denim quality variables considered were: color, odor, appearance and soft handle. The tests were started on a pilot scale following complexity factors attributed to the processes, in denim fabric and jeans, which demonstrated the possibility of reuse, because there was no interference in the processes and at quality of the tested product. Industrial scale tests were initiated by a step control that confirmed the methodology efficiency applied to identify the possibility of reuse by tests that precede each recipe to be processed. 556 replicates were performed in production scale for 47 different recipes of denim washing. The percentage of water reuse was 100% for all processes and repetitions performed after the initial adjustment testing phase. All the jeans were framed with the highest quality for internal control and marketed, being accepted by contractors. The full-scale use of treated wastewater, supported by monitoring and evaluation and control methodology suggested in this study, proved to be valid in textile production, not given any negative impact to the quality the produced jeans under the presented conditions. It is believed that this methodology can be extrapolated to other laundries to determine the possibility of reuse in denim washing wet processing with the necessary modifications to each company.
Resumo:
Aqueous-based polyurethane dispersions have been widely utilized as lubricants in textile, shoes, automotive, biomaterial and many other industries because they are less aggressive to surrounding environment. In this work thin films with different thickness were deposited on biocompatible polyurethane by plasma polymerization process using diethylene glycol dimethyl ether (Diglyme) as monomer. Molecular structure of the films was analyzed by Fourier Transform Infrared spectroscopy. The spectra exhibited absorption bands of O-H (3500-3200cm(-1)), C-H (3000-2900cm(-1)), C=O (1730-1650cm(-1)), C-O and C-O-C bonds at 1200-1600cm(-1). The samples wettability was evaluated by measurements of contact angle using different liquids such as water, glycerol, poly-ethane and CMC. The polyurethane surface showed hydrophilic behavior after diglyme plasma-deposition with contact angle dropping from 85(0) to 22(0). Scanning Electron Microscopy revealed that diglyme films covered uniformly the polyurethane surfaces ensuring to it a biocompatible characteristic.
Resumo:
Polyester fibers are the most used fibers in the world and disperse dyes are used for dyeing these fibers. After dyeing, the colorful dyebath is discharged into effluent streams, which needs a special treatment for color removal. Surfactants interaction with dyes has been evaluated in several studies, including the textile area, specifically in the separation of dyes from textile wastewater. In this work a cationic surfactant was used in a microemulsion system for the extraction of anionic dyes (disperses dyes) from textile wastewater. These microemulsion system was composed by dodecylamonium chloride (surfactant), kerosene oil (organic phase), isoamyl alcohol (cosurfactant) and the wastewater (aqueous phase). The wastewater that results after the dyeing process is acid (pH 5). It was observed that changing the pH value to above 12.8 the extraction could be made, resulting in an aqueous phase with low color level. The Scheffé net experimental design was used for the extraction process optimization, and the obtained results were evaluated using the program "Statistica 7.0". The optimal microemulsion system was composed by 59.8wt.% of wastewater, 30.1wt.% of kerosene, 3.37wt.% of surfactant and 6.73wt.% of cosurfactant, providing extraction upper than 96%. A mix of reactive dyebath (50%) and disperse dyebath (50%) was used as aqueous phase and it presented extraction upper than 98%. The water phase after extraction process can be reused in a new dyeing, being obtained satisfactory results, according to the limits established by textile industry for a good dyeing. Tests were accomplished seeking to study the influence of salt addition and temperature. An experimental design was used for this purpose, which showed that the extraction doesn't depend on those factors. In this way, the removal of color from textile wastewater by microemulsion is a viable technique (that does not depend of external factors such as salinity and temperature), being obtained good extraction results even with in wastewater mixtures
Resumo:
In this work, the treatment of synthetic wastewaters containing Remazol Red BR (RRB) and Novacron Blue C-D (NB) by anodic oxidation using boron doped diamond anodes (BDD) and Novacron Yellow (YN) using BDD and Platinum (Pt) anodes was investigated. Galvanostatic electrolyses of RRB and NB synthetic wastewaters have led to the complete decolorization removal at different operating conditions (current density, pH and temperature). The influence of these parameters was investigated in order to find the best conditions for dyestuff colour removal. According to the experimental results obtained, the electrochemical oxidation process is suitable for decolorizing wastewaters containing these textile dyes, due to the electrocatalytic properties of BDD and Pt anode. Energy requirements for removing colour during galvanostatic electrolyses of RRB, NB and YN synthetic solutions depends mainly on the operating conditions; for example for RRB, it passes from 3.30 kWh m-3 at 20 mA cm-2 to 4.28 kWh m-3 at 60 mA cm-2 (pH = 1); 15.23 kWh m-3 at 20 mA cm-2 to 24.75 kWh m-3 at 60 mA cm-2 (pH = 4.5); 10.80 kWh m-3 at 20 mA cm-2 to 31.5 kWh m-3 at 60 mA cm-2 (pH = 8) (data estimated per volume of treated effluent). In order to verify the Brazilian law regulations of NB and RRB synthetic solutions after electrochemical decolourisation treatment, Hazen Units values were determined and the total colour removal was achieved; remaining into the regulations. Finally, electrical energy cost for removing colour was estimated
Resumo:
In this work, electrochemical technology was used to treat synthetic wastewater containing Methyl Red (MR) and Blue Novacron (BN) by anodic oxidation using anodes platinum (Pt) and real samples of textile effluents using DDB anodes and platinum (Pt). The removal of color from the galvanostatic electrolysis of synthetic wastewater MR and BN, and the actual sample has been observed under different conditions (different current densities and temperature variation). The investigation of these parameters was performed in order to establish the best conditions for removal of color and chemical oxygen demand (BOD). According to the results obtained in this study, the electrochemical oxidation processes suitable for the degradation process of color and COD in wastewater containing such textile dyes, because the electrocatalytic properties of Pt and BDD anodes consumption energy during the electrochemical oxidation of synthetic solutions AN and MR and real sample, mainly depend on the operating parameters of operation, for example, the synthetic sample of MR, energy consumption rose from 42,00kWhm-3 in 40 mAcm-2 and 25 C to 17,50 kWhm-3 in 40mAcm-2 and 40 C, from the BN went 17,83 kWhm-3 in 40mAcm and 40°C to 14,04 kWhm- 3 in 40mAcm-2 and 40 C (data estimated by the volume of treated effluent). These results clearly indicate the applicability of electrochemical treatment for removing dyes from synthetic solutions and real industrial effluents
Resumo:
Gels consist of soft materials with vast use in several activities, such as in pharmaceutical industry, food science, and coatings/textile applications. In order to obtain these materials, the process of gelification, that can be physical (based on physical interactions) and/or chemical (based on covalent crosslinking), has to be carried out. In this work we used dynamic light scattering (DLS) and rheometry to monitor the covalent gelification of chitosan solutions by glutaraldehyde. Intensity correlation function (ICF) data was obtained from DLS and the exponential stretched Kohrausch-William-Watts function (KWW) was fitted to them. The parameters of the KWW equation, β, Γ and C were evaluated. These methods were effective in clarifying the process of sol-gel transition, with the emergence of non-ergodicity, and determining the range of gelation observed in about 10-20 minutes. The dependence between apparent viscosity on reaction time was used to support the discussion proposed.
Resumo:
The phenomenon of adsorption is of fundamental importance for the treatment of textile effluents and removal of dyes. Chitosan is characterized as an excellent adsorbent material, not only for its adsorption capacity but also the low cost production. Equilibrium and kinetic studies were developed in this study to describe the mechanism of adsorption of the anionic azo dye Orange G in chitosan, with the isotherms obtained from the variation of the concentration of dye in the continuous phase. The kinetics of the process was analyzed based on models involving the adsorption of molecules of the dye in nonpolar and polar sites. Adsorption experiments were carried out in water and in saline media with different NaCl concentrations, both for the determination of the equilibrium time as isotherms for making kinetic curves in which the amount of dye adsorbed measured indirectly varied with time. The experiments revealed the opening of the biopolymer structure with increasing concentration of Orange G, accompanied by high pH values and change on the type of interaction between the dye and the adsorbent surface, suggesting behavior advocated by the Langmuir equation in a certain range of concentration of the adsorbate and following the Henry's Law at higher concentrations, from the increased number of sites available for adsorption. The studies conducted showed that the saline medium reduces the chitosan s adsorption capacity according to a certain concentration, the occurrence of the cooperative adsorption process steps kinetic mechanism suggested as a new alternative for the interpretation of the phenomenon
Resumo:
Textile activity results in effluents with a variety of dyes. Among the several processes for dye-uptaking from these wastewaters, sorption is one of the most effective methods, chitosan being a very promising alternative for this end. The sorption of Methyl Orange by chitosan crosslinked particles was approached using equilibrium and kinetic analyses at different pH s. Besides the standard pseudo-order analysis normally effectuated (i.e. pseudo-first-order and pseudo-second-order), a novel approach involving a pseudo-nth-order kinetics was used, nbeing determined via non-linear regression, using the Levenberg-Marquardt method. Zeta potential measurements indicated that electrostatic interactions were important for the sorption process. Regarding equilibrium experiments, data were well fitted to a hybrid Langmuir-Freundlich isotherm, and estimated Gibbs free energy of adsorption as a function of mass of dye per area of chitosan showed that the process of adsorption becomes more homogeneous as the pH of the continuous phase decreased. Considering the kinetics of sorption, although a pseudo-nth-order description yielded good fits, a kinetic equation involving diffusion adsorption phenomena was found to be more consistent in terms of a physicochemical description of the sorption process
Resumo:
We evaluated, in two locations, production and fiber quality of cultivar IAC 23 cotton plants in ultra-narrow row, narrow row and conventional row spacing, varying number of plants by linear meter. Two experiments had been lead, one in Piracicaba - SP and another one in Campinas - SP, both in the crop year 2001/02. The experimental design was randomized blocks, in a factorial scheme, with 4 replications, being three spacing rows: 0.38m (ultra-narrow), 0.76m (narrow), and 0.95 m (conventional); and four densities (5, 8, 11, and 14 plants by linear meter). In Piracicaba, the production of cotton was 12% and 8,4 % superior in the ultra-narrow row and narrow row, respectively, when compared to the conventional row. In the ultra-narrow row in the smaller density of plants in the line, the production of cotton was 29.2% and 22.3% superior, respectively, to the productions of the narrow row and conventional row in the same number of plants in the line. The smaller spacing and higher plant density on the line, the smaller the number of bolls per plant at both locations. The agronomic characters of laboratory and the technological characteristics of the fiber were not modified by the populations of plants in the two studied environments.
Resumo:
This study has as main objective to verify the effect of the tax and financial incentives granted by the brazilian states, specially in the reduction of ICMS on the investment decision of the entities, which in the last years led to the companies to decide new projects in based on the region that presented the better infrastructure beyond lesser tributary expense. For in such was made an economic valuation of the companies with focus in the beneficiary s optics using an adaptation of the Discounted Cash Flow method to measure the impact of the tax incentives in the value of the companies, this study selected the textile industry segment located in the State of Rio Grande do Norte, Brazil. The results indicated that such incentives created addition in the value of the companies, however the inexistence of incentives would not be enough to a negative decision of investment in the Rio Grande do Norte. The smallest difference between the value with and without incentive observed was 8.9%, and the biggest 31.7%, and the average of value aggregation with the tax incentives represented 18.9%
Resumo:
The paper demonstrates how it is organized production chain of natural gas in Rio Grande do Norte and highlights some prospects for this sector. The study is backed by elements to understand the process of innovation as the driving force of capitalist dynamics as well as the features of the Brazilian economy in the years 1990 and 2000 that indicated the development of natural gas production in the energy matrix Brazil. It was found that the state has potiguar possibilities for structuring an energy based on elements from the region and with prospects of becoming self-sufficient in electricity, where natural gas has a share of participation in this segment. The automotive and industrial are the biggest consumers of this input. With emphasis on the textile industry. Signaling to a broad horizon of supply, this sector will depend on their investments in research and Deficient, and the policy adopted by government to develop the consumer market
Resumo:
The process of globalization which has characterized today s Brazilian economic development is determining in the restructuring of productive capital, influencing the development of an economic model, founded on greater competition and use of technology. As a consequence of that, there has been a certain disorganization of the economy, the growth of social inequalities and the lack of structuring of the labor market and the social security system. This has favored a rapid growth of the urban informal economy in Brazil. In Rio Grande do Norte state, the Greater Natal area is the main production center. This is where this study found 58 informal textile industries. In the research, the organizational structure of these industries, characterized by intensive use of labor vis-à-vis the use of capital, problems with putting production in the market place, although links with the formal sector were evident, is analysed. The research also focuses on the relationship labor x capital, the nature and volume of the industrial activity in the 58 industries, their proprietors and 120 employees
Resumo:
The Feira da Pedra is an extension of the open fair of São Bento in the State of Paraiba. It is a system of trade in textile goods produced by textile industry in manufacturing of hammocks and derivatives of this industry, present in some cities in the state of Paraiba and Rio Grande do Norte, as a survival strategy, inserted in the list of tertiary and retail of the urban economics of this city. It is thereby aimed to discuss about the urban economics, reflecting on the open fair system from the two circuits of urban economy, mainly in the context of the dynamics of the current period of geographic space, the technical-scientific-informational period, as the specific empirical object, the Feira da Pedra of São Bento (PB). For this, this research was carried out in two stages of operation: a) surveys of secondary data and b) primary data collection which were reported an operational triad: I) literature; II) documentary research, and III) research of field. The presence of the Feira da Pedra in São Bento has shown us one of the most important characteristics of this city, in order to present major economic, social and cultural benefits to the local population, and contribute to (re) production of sertanejo space, making lower part of the circuit of its urban economy. This activity has entailed several dynamics for urban space in this city, mainly because of attracting large numbers of people, carrying typical actions of its relationship with the urban space are são-bentense and built environment. Thus, its importance is not only a local and regional phenomenon, but also a cultural reference of a place in the geographical area of many paraibanos and norte-rio-grandenses subjects, as the case of this activity has brought to its weekly routine, this product resulting from the textile working of this area of Sertão Paraibano and Seridó Potiguar