Estudo do comportamento químico e ambiental de efluentes industriais e resíduos sólidos oriundos de lavanderias do polo têxtil no agreste pernambucano

Abstract

The state of Pernambuco is considered one of the largest textile industrial centers in the country and among the cities that make up the Local Productive Arrangement, Caruaru stands out, considered a large urban and textile center of Agreste, with the most important companies in this sector. The textile laundries are an industrial activity with great potential for contamination of the environment due to the solid waste quality and effluent generated, since they contain a significant load of polluting compounds from the numerous dyeing processes of jeans and other materials. The textile sludge is characterized as carrying a wide variety of heavy metals, organic and inorganic compounds from the dyes, fibers auxiliary processes. With the objective of carrying out studies to reuse this sludge in the region, we developed a series of approaches from the detailed description of the dyeing processes, to the characterization and behavior of the chemical composition of effluents and solid wastes from some laundries. For this, modeling studies of the chemical behavior of metals (Cadmium, Chromium, Copper, Iron, Manganese, Nickel, Lead, Zinc) present in crude and treated effluents were carried out, as well as the ecotoxicological analyzes with Daphnia Similis and organic matter from four different Textile sludges generated by laundries located in the Agreste of Pernambuco. Some results suggest that the behavior of the metals in the effluents presents in several chemical forms that may in turn complex in different ways with the fibers of the tissues released during the dyeing processes. It is still possible that such metals form bonds with compounds remaining in the processes at the Effluent Treatment Station. With the results of the ecotoxicological analyzes, it is possible to determine the degree of toxicity differentiated in some samples of textile sludge, being classified as class I hazardous waste according to NBR 10.004/2004. Some additional analyzes in the same sludge, such as organic matter content, pH and Eh indicated high correlation between each other and with toxicity. According to the results obtained, it is evident that there is a need to improve the efficiency of the effluent treatment plants, as well as to find alternatives for the use of the basic raw material of the inorganic pigments rich in heavy metals. It was also evident that there is a need for more detailed characterization and constant monitoring of the liquid effluents and solid residues generated by the textile activity in the state of Pernambuco to measure the degree of environmental impact present in the aquatic bodies and soils of the region. However, once the effluent treatment processes are improved, it is possible to reuse all biomass in local industry as a substitute for firewood, thereby reducing waste disposal and transport costs, thereby reducing the environmental impacts of the textile industry.