EFEITO DA ADIÇÃO DE RESÍDUO DE MALTE DA INDÚSTRIA CERVEJEIRA NO PROCESSO DE COMPOSTAGEM

Abstract

Solid waste originating in beer production is by-products resulting from the use of malt grains, mainly composed of malted barley husks. These residues represent the main by-product of the brewing industry. Composting appears as a simplified and economically advantageous method for treating this waste, standing out for its low cost and the need for highly specialized labor. The present study aimed to analyze the efficiency of biodegradability of processed starch and malt waste material from the brewing industry in the composting process. The experiments were conducted at the Universidade Estadual do Centro-Oeste (Unicentro), Irati Campus, using nine compost bins, 36 liters each. The preparation of the compost included dry pruning branches and leaves as waste, with a proportion of 70% and 30% organic waste, of which 10% was target material and 20% fruit and vegetable waste. The behavior observed during the experiments highlighted the notable influence of external temperature variation on the composting process, accentuated due to the specific characteristics of the study environment. The pH showed fluctuations, indicating self-control by microorganisms, remaining in a range, between 6.5 and 9.6, suitable for successful composting. Humidity was monitored to ensure the survival of microorganisms, with emphasis on composters 2 and 3 and the capacity to retain liquids through starch, which contributed to greater humidity in these devices, impairing the diffusion of oxygen, reducing the temperature and providing conditions anaerobic. In relation to organic matter, throughout the experiment, mitigation was observed in all composters, with levels above 30% compost reduction, indicating process efficiency. The Principal Component Analysis - PCA indicated an inversely proportional relationship on the parameters temperature and organic matter, corroborating the literature, Basal Compost Respiration - BCR expressed greater microbial activity in the control compost bin, indicating greater release of CO2 in relation to the others, contributing to enhance the greenhouse effect. The Microbial Biomass - CBM also showed the control composter as more unstable compared to the others. For the Metabolic Quotient - qCO2, responsible for the ratio between RBC and C-BMC, the composters demonstrated values below the control composter. It is concluded that the addition of starch and malt bagasse residues promoted greater efficiency in the composting process, resulting in more stable compounds and less release of CO2 compared to the compost bin without addition of study material. Therefore, the degradability potential of the material was highlighted, despite the unfavorable thermal conditions at the study site, the values obtained denoted efficiency in the process, with results in accordance with the parameters described in the literature, and the impossibility of identifying the source material used. for composting after a certain period. Therefore, considering the volume of malt bagasse waste from the brewing industry and the degradation time, the composting process represents an efficient alternative to the treatment of this waste, as well as a viable technique to promote greater sustainability in production processes in this productive sector.