Caracterização de Efluente Têxtil e Proposta de Tratamento

Textile industry deals with a high diversity of processes and generation of wastewaters with a high content of pollutant material. Before being disposed of in water bodies, a pre-treatment of the effluent is carried out, which is sometimes ineffective. In order to be properly treated, physical and chemical properties of the effluent must be known, as well as the pollutant agents that might be present in it. This has turned out to be a great problem in the textile industry, for there is a variety of processes and the pollutant load is very diversified. The characterization of the effluent allows the identification of most critical points and, as a consequence, the most appropriate treatment procedure to be employed, may be chosen. This study presents the results obtained after characterizing the effluent of a textile industry that comprises knitting, dyeing and apparel sections, processing mainly polyester/cotton articles. In this work, twenty samples of the effluent were collected, and related to the changes in production. From the results, a statistical evaluation was applied, determined in function of the rate of flow. The following properties and pollutants agents were quantitatively analysed: temperature; pH; sulfides; chlorine; alcalinity; chlorides; cianides; phenols; color; COD (Chemical Oxygen Demand); TOC (Total Organic Carbon); oil and grease; total, fixed and volatile solids; dissolved, fixed and volatile solids; suspended, fixed and volatile solids; setteable solids and heavy metals such as cadmium, copper, lead, chromium, tin, iron, zinc and nickel. Analyses were carried out according to ABNT NBR 13402 norm, based upon Standard Methods for the Examination of Water and Wastewater. As a consequence, a global treatment proposal is presented, involving clean production practices as contaminant load reducer, followed by conventional (biological) treatment

Estudo da produção de pectinase por fermentação em estado sólido utilizando pedúnculo de caju como substrato

Pectinolytic enzymes, or simply pectinases, are complex enzymes that degrade pectic polymers. They have many uses, such as fruit juice extraction and purification, textile fiber treatment and vegetal oil extraction. The aim of this work was to study the kinetics of pectinases production by solid-state fermentation, using dry cashew apple residue as substrate and the microorganism Aspergillus niger CCT 0916. The influence of the initial medium moisture and medium supplementation with a source of nitrogen and phosphorus was evaluated using the factorial experimental planning and response surface methodology. Ammonia sulphate and potassium phosphate were used as nitrogen and phosphorus source, respectively. The variables time of contact (T) and ratio volume solvent/fermented medium (RZ), in systems with and without agitation, were evaluated in order to study the best extraction condition of the produced enzyme. Washed and unwashed cashew apple residues were tested as the growth medium. The unwashed residue was obtained by drying the residue after the extraction of the juice, while the washed residue was obtained by water washing 5 times using the proportion of 1 kg pulp/2 liters of water. Samples were taken every 12 hours for moisture content, pH, protein, reducing sugars, polygalacturonase activity (PG) and viscosity reduction. The physical-chemical composition of the residues had different sugar and pectin levels. For the unwashed residue, the peak activity was reached with 40% of initial moisture content, 1% of nitrogen supplementation without phosphorus addition after 30 hours of process. These conditions led to 16 U/g of PG activity and 82% of viscosity reduction. The calculated models reached similar values to the experimental ones in the same process conditions: 15.55 U/g of PG and 79.57% of viscosity eduction. Similarly, the greatest enzyme production for washed residue was reached with 40% initial moisture content, 1% nitrogen supplementation without phosphorus addition after 22 hours of cultivation. In this condition it was obtained polygalacturonase activity of 9.84 U/g and viscosity reduction of 81.36%. These values are close to experimental values that were of 10.1 U/g and 81%, respectively. The conditions that led to the best PG activity results was the agitated one and the best extraction condition was obtained with 100 minutes of solvent/medium contact and RZ of 5 (mL/g)

Aplicação da água residuária das salinas no tratamento de efluente têxtil

The treatment of colored and alkaline effluent has been a challenge to the textile industry. An alternative to remove the colors of those effluents is applying magnesium chloride as a coagulant agent. The magnesium ion, in high pH, hydrolyzes itself, forming the magnesium hydroxide which has a large adsorptive area and positive electrostatic charges able to act as an efficient coagulant. The bittern wastewater from the salt industries has been studied as a potential font of this magnesium ion. Nowadays, this bittern wastewater is evicted into the sea, without any treatment or other use. This thesis has evaluated the potential of applying the wastewater from the salt industries in the treatment of dyeing effluent containing indigo dye and alkaline pH. All the experiments were made in jar tests simulating the chemical coagulation, flocculation and decantation steps ranging the pH and the concentration of magnesium ion. Were obtained removals between 96% and 76% for turbidity, apparent color, and true color, respectively, using 200mg/L Mg2+. The reduction of costs with acid, when were used the salt industries wastewater, comparing with Al2(SO4)3, was 62%. For the degradation of organic matter remaining in the clarified, around 900 mg/L, was applyed the advanced process of oxidation: photo-Fenton. The preliminary results showed 57% reduction in DOC. According to the results obtained, the salt industries wastewater can be applied, as coagulant, in the physical-chemical treatment of the denim dyeing wastewater, so it is not necessary a previous adjust of pH, efficiently and economically

Sistemas microemulsionados aplicados à remoção da cor de efluente têxtil

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%

Reúso de água no processamento de jeans na indústria têxtil

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.

Utilização de microemulsão na remoção da cor de efluentes têxteis contendo corantes dispersos

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

Tecnologia eletroquímica como tratamento alternativo de efluentes têxteis sintéticos utilizando ânodos de platina e diamante

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

Aplicação da tecnologia eletroquímica como alternativa para a remoção de corante têxteis em efluentes sintéticos e reais utilizando anodos de platina e diamante

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

Caracterização do processo de gelificação de soluções quitosana utilizando reometria e espalhamento dinâmico da luz

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.

Estudo do equilíbrio e cinética de adsorção de um corante aniônico em quitosana

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

Estudos de sorção de um corante aniônico modelo em partículas de quitosana reticulada

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

Avaliação econômica dos incentivos fiscais e financeiros: uma análise das empresas industriais têxteis localizadas no Rio Grande do Norte, no período de 1999 a 2003

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%

A cadeia produtiva de gás natural no Rio Grande do Norte e perspectivas para o setor

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

Indústria informal de confecções e mercado de trabalho :um estudo sobre a grande Natal (1977-2003)

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

Feira livre e circuitos da economia urbana: um estudo da feira da Pedra, em São Bento (PB)

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