Abstract The process of beneficiation of a peaty ceramic raw material extracted from the Poços de Caldas region, MG, through the composting method to reduce organic matter (OM) was analyzed. The raw materials used in separate piles were divided, keeping one of the samples pure (TP) and adding bovine wastes in the second (TB). The process lasted 6 months and, at the end of each month, the amount of MO was analyzed by the Walkley-Black method. Results of maximum degradation of 56%±6% of OM in the TB and 47%±5% of OM in the TP were obtained. The ceramic characterization of the processed raw material was then carried out. It has been proved that the proposed method is efficient for the decrease of OM in the ceramic raw material. Regarding the composting product, the results were positive, showing that this material can be used in ceramic applications.

A fluidized bed reactor was used to study the degradation of the surfactant linear alkylbenzene sulfonate (LAS). The reactor was inoculated with anaerobic sludge and was fed with a synthetic substrate supplemented with LAS in increasing concentrations (8.2 to 45.8 mg l-1). The removal efficiency of 93% was obtained after 270 days of operation. Subsequently, 16S rRNA gene sequencing and phylogenetic analysis of the sample at the last stage of the reactor operation recovered 105 clones belonging to the domain Bacteria. These clones represented a variety of phyla with significant homology to Bacteroidetes (40%), Proteobacteria (42%), Verrucomicrobia (4%), Acidobacteria (3%), Firmicutes (2%), and Gemmatimonadetes (1%). A small fraction of the clones (8%) was not related to any phylum. Such phyla variety indicated the role of microbial consortia in degrading the surfactant LAS.

An anaerobic fluidized bed reactor was used to assess the degradation of the surfactant linear alkylbenzene sulfonate (LAS). The reactor was inoculated with sludge from an UASB reactor treating swine wastewater and was fed with a synthetic substrate supplemented with LAS. Sand was used as support material for biomass immobilization. The reactor was kept in a controlled temperature chamber (30±1 ºC) and operated with a hydraulic retention time (HRT) of 18 h. The LAS concentration was gradually increased from 8.2±1.3 to 45.8±5.4 mg.L-1. The COD removal was 91%, on average, when the influent COD was 645±49 mg.L-1. The results obtained by chromatographic analysis showed that the reactor removed 93% of the LAS after 270 days of operation.