Modelo de gestão ambiental para reúso de águas de lavanderias do agreste de Pernambuco

Abstract

The unavailability of water in the local textile business in Pernambuco forces local companies to seek out strategies to manage this natural resource. The reuse of water employed in the industrial process would lead to the economy of such resource. The present work aims to propose an environmental management strategy to industrial laundry services in Pernambuco’s semiarid with emphasis on reusing water and moving towards higher hydric efficacy as well as post-treatment effluent analysis and assessment of the strategies implemented. Industrial laundries are burdened with a higher production cost when compared with other clothing industry companies. Due to their location in the semiarid, industrial laundries are mostly supplied by rented water trucks increasing the industrial processes’ maintenance costs and lowers the net financial income of this enterprise. In this research a direct survey was applied in the laundries to obtain data of the employees and companies profiles. An analysis of the companies’ effluents was performed in order to determine the environmental management and patterns of reuse of treated effluent. The laundries employ mostly men (84%), with education level composed middle-school (47,34%). Such data are relevant to develop public policies towards reducing the schooling gap abovementioned with incentive programs aiming to increase schooling and qualification, promotion of technical courses in this field and creation of textile engineering university graduation. When it comes to the industries profile, it has been evidenced by the survey that most are run as family business and 73,68% are considered to be either small or micro enterprises employing between 5 and 10 workers. The environmental management employed by laundries in Pernambuco’s semiarid is claimed to be present, in conformity with the state’s ruling, in 63% of the laundries surveyed, though only 52% had an employee hired specifically for the job. The monitoring of the effluents produced is performed in 94% of the surveyed companies in a monthly schedule by external laboratories as requested by the overseeing state’s environmental agency (CPRH). Laundries use an average of 42.000 liters of water daily, with monthly expenses around 6.000 Brazilian Reais and 89% of the companies declared they reuse water, 63% in direct reuse, 26,5% in indirect reuse and 10,5% did not practice reuse in their facilities. The analysis performed in the industrial effluent evidenced that in 45% the efficacy was above 60%, only true color, Cr, CDO and BDO presented values below 60%, respectively 31%, 18%, 43% and 15,8%. The legal prerequisites of effluent disposal were accomplished in all but 3 items that were manganese, CDO and BDO. Therefore, it is necessary to apply corrective measures in the treatment stations to improve the abovementioned parameters in the effluent to fulfill the law. Concerning organic matter, implementing secondary treatment is would highly improve the efficacy of the procedures. Reuse is possible, however, concerning hardness the implementation of adjunctive treatment targeting adjustment in that area as well as in ionic iron and manganese in fulfillment of the British Textile Confederation. Turbidity is also another parameter that needs adjustment, as seen in the Royal Decree 1620/2007 of the Spanish government to industries. It has been also proposed a cleaner base environmental management models with partnership-making and industrial symbiosis.