Combination of physical-chemical processes in the treatment of tannery wastewater

• Grant number: 12/05428-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2012
• End date: June 30, 2013
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Principal Investigator: Maria Cristina Rizk
• Grantee: Cássio Tamogami
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

The leather industries are among the most potentially polluting activities. The production of 250 kg of soft leather demands approximately 30,000 liters of water and generates solid, liquids and gaseous wastes. The wastewater is rich in organic material, salt, sulfates, dyes, potentially toxic chromium, among other pollutants that cause impacts to the soil, water and air. The usually tannery wastewater treatment consists in the grating and fat retention, followed by coagulation, flocculation, sedimentation and activated sludge. However, these methods are partial in the degradation of the pollutants and it's necessary to study more advanced techniques for the effectiveness treatment of this effluent. So, the purpose of this study is to treat the tannery wastewater by coagulation/flocculation/sedimentation followed by H2O2/artificial UV. It will be tested chemical and natural coagulants; and it will be optimized the coagulation/flocculation/sedimentation parameters (coagulant concentration and pH) and the H2O2/UV parameters (hydrogen peroxide concentration, pH and time of exposure to the UV radiation). The wastewater will be characterized at the beginning and at the end of the experiments by the parameters pH, COD, color, turbidity, solids and chromium. Thus the expected results are the possibility of the tannery wastewater to be treated by a quick, efficient and relatively simple process, aiming the promotion of improvements in the public health and the environmental conservation. (AU)