Aplicação de ultrafiltração e osmose reversa para reúso de efluente terciário como pré-tratamento na produção de água desmineralizada em indústria de papel e celulose

Abstract

In the pulp and paper industry there is a constant concern about the growing consumption of industrial water, in view of the frequent water crises in the state of Paraná and the volume of withdrawal necessary for the production process. Aiming to implement the circular economy of water consumption reduction in the industry, this work analyzed all areas that use the fluid for operation and proposed the reuse of the tertiary effluent as an input stream in the demineralized water treatment plant (ETAC). To this end, a characterization analysis of the tertiary effluent was performed in order to select the appropriate treatment for reuse. A preliminary adsorption test was performed, proving its effectiveness in removing color and turbidity. In search of methodologies to remove color, turbidity, conductivity, COD and TSS, an ultrafiltration (UF) system integrated with reverse osmosis (RO) was proposed. Computational simulations representing the integrated membrane separation process, performed in SuperPro Designer® software, showed that the applied methodology is consistent and effective. A total of 88.56% of water was recovered, with the objective of reusing it as feed stream for the demineralized water station. The economic report of the equipment generated by the simulator, in comparison with the gains of the plant, stipulates an approximate financial return in 32 days. It can be concluded that, with the implementation of the membrane system, it will be possible to reduce water consumption, which would result in a productive and economic increase, making the pulp and paper industry more circular and sustainable.