Gerenciamento de resíduos de filtros de óleo de motores dos ciclos otto e diesel: separação, caracterização e avaliação da viabilidade econômica em concessionárias automotivas

Abstract

Used automotive oil filters require waste management practices that account for residual oil and the diversity of their constituent materials. This study aimed to assess the technical and economic feasibility of an alternative management approach based on separating used oil filters from Otto- and Diesel-cycle engines and comparing waste disposal scenarios. Administrative records from 11 automotive dealerships located in the Brazilian states of Piauí, Ceará, and Paraíba were analyzed. The researchers performed experimental filter disassembly and physical separation procedures, along with gravity drainage tests on 20 filters. The study also included density measurements of used or contaminated lubricating oil (UCLO), vehicle fleet projections, and economic estimates. Between April 2024 and March 2025, 52,235 used filters were recorded, with reported masses of 16,650 kg for complete filters and 4,250 kg for filter elements. Gravimetric characterization of a single 342 g filter revealed a metallic component content of 73.10%, which cannot be generalized to other filter models. Gravity drainage reduced filter mass by 29.19% for large filters and 25.52% for small filters, with mean mass reductions of 129.70 ± 3.92 g and 69.80 ± 11.02 g per filter, respectively. The mean UCLO density was 0.9392 g/mL, which was used to estimate a total volume of 2,124.19 mL associated with the mass reductions observed in the 20 filters, assuming that these reductions resulted entirely from oil removal. Mathematical projections indicated vehicle fleet growth through 2035 but did not establish a proportional increase in used oil filter generation. Based on a disposal tariff of BRL 3.07/kg, the potential differences in disposal costs between the evaluated scenarios ranged from BRL 38,068.00 to BRL 44,396.68, without fully accounting for operational costs. The results supported developing a proposed Standard Operating Procedure (SOP), which has not yet been validated or systematically implemented at the dealerships. It was concluded that physical component separation and mass reduction through gravity drainage were demonstrated under the experimental conditions investigated, providing a technical basis for improving used oil filter management. However, the decontamination of separated fractions, disposal suitability, and economic feasibility remain unverified.