HAZOP TOOL APPLIED TO THE SEWAGE TREATMENT PLANT BY ACTIVATED SLUDGE PROCESS, IN THE CITY OF ALTAMIRA/PA

Abstract

The stages of a Sewage Treatment Plant require safeguards during its processes, in order to ensure the integrity of the operational team, the surrounding community, in addition to the sustainability of natural resources. Thus, accident analysis is a primary component in any industrial activity, and in the context of sewage treatment, it has great relevance, given the 1,419 accidents recorded between the years 2012 and 2022. This study is innovative, standing out for its pioneering approach in the application of risk analysis during the secondary treatment phase for activated sludge, thus filling an existing gap in academic research on this topic. The methodology applied was the HAZOP, as it is a consolidated technique to evaluate the efficiency of these operations. 5 study nodes were adopted for the analysis of 18 parameters covering the entire sludge treatment process. Based on the results obtained, 65 scenarios were identified, of which 35 (54%) were classified as acceptable risk, 30 undesirable (46%) and none unacceptable. Regarding frequency, 92% of the events analyzed were covered, and those events with a higher probability of occurrence were classified as having a low degree of severity (acceptable or unwanted risk). Regarding severity, 94% of the events analyzed had little harmful potential. In addition to analyzing the reasons and implications of the scenarios, the adoption of preventive measures and mitigation of the consequences was suggested. In addition, a technical note was prepared containing information for the reuse of sewage sludge, in order to reduce the amount sent to the Altamira landfill.