Compostagem de resíduos da filetagem de tilápia e poda urbana

Abstract

Fish waste, when disposed of incorrectly, generates a serious environmental problem. In this context, composting can be an alternative for the treatment of this waste, adding value to this material. This work aimed to test the composting of waste from tilapia filleting using urban pruning as a source of carbon in different proportions. The research was conducted in the experimental area of the UTFPR Campus, in the municipality of Francisco Beltrão - PR. The experiment was organized in a completely randomized design (DIC), with three treatments and four replications. The residue proportions in each treatment were: T1: 10kg carcass for 70kg of urban pruning, T2: 16kg carcass for 70kg and T 35kg carcass for 70kg. Analyzes of temperature, pH, water content, solids content was conducted, and the TOC value was estimated for monitoring the experiment. The maximum temperature recorded in T1 was 60.1ºC, on the 19th day of composting, in treatments T2 and T3 this peak occurred on the 15th day, reaching 61.3ºC and 62.3 respectively. The water content of the compost remained above 50% in the three treatments with weeks in which its content remained above 60%, the final pH of T1, T2 and T3 were 8.39, 8.34 and 8.38, respectively. Volatile solids showed a decay of 27.6% for T1, 31.3% for T2 and 22.1% for T3 and total organic carbon (TOC) showed a decay of 15.32, 17.32 and 12.27 % for treatments T1, T2 and T3, respectively. Tukey's test for comparing the means of the treatments, with a significance level of 5%, indicated that there was no difference between the results, which were considered statistically equal. The combined composting of tilapia carcass and urban waste resulted in a mature final compost, with stabilization of organic matter in 70 days, regardless of the treatment compositions, allowing efficient treatment for different proportions of waste in the same time interval.