PH Analysis of an Wastewater Treatment Plants (WWTP) in a Paper Recycling Industry

Abstract

The paper industry in its production process consumes a large amount of water, and the flow of effluent is very variable, being related to the manufacturing process used in production capacity. Effluents are formed by complex mixtures of chemical compounds. The wide composition variability among the effluents from the most diverse origins, added to the market entry of numerous chemical substances every year, which will become part of the effluents, makes the complete characterization of its composition very difficult. To characterize the effluent, some parameters are analyzed, which may be physical, chemical or bacteriological. The pH, which is directly related to the coagulation efficiency, as it influences the chemistry of the coagulants, their reactions in the aqueous environment, the predominant hydrolysed species and the variation in surface charge of colloids present in the effluent, where in the aqueous system it is typically measured by use of a pH meter. Therefore, the objective of this study was to perform an effluent treatment plant (ETE) analysis of a paper recycling industry, the inlet and outlet flow values ​​of the WWTP, using the pH parameter, comparing the dry periods, flood and transition from August 2018 to July 2019. Initially, a survey of technical documents related to the effluent treatment process and the verification of the standard norms, in use in the Industry WWTP was carried out. The collections were performed bimonthly, observed at times that did not interfere in the results and identified according to CONAMA Resolution, nº 430/2011. The pH values ​​obtained at the WWTP revealed an improvement in the quality of the effluent treated in accordance with current legislation. However, although the effluent was adequate for the release pattern, the high toxicity found in the inlet and outlet pH of the WWTP, evidences the need to define new treatment and / or control strategies to comply with the legislation regarding this parameter.