BIOCHEMICAL TREATMENT OF WASTEWATER FROM CANNING COMPANIES FOR BIOGAS AND DIGESTATE PRODUCTION

Canneries are a powerful source of wastewater. Wastewater is produced at various stages of the technological process and is contaminated with carbohydrates, proteins, fats, etc. Often, such wastewater is not treated or discharged into natural reservoirs incompletely treated. It is advisable to use methane fermentation. This biotechnological process will contribute to the removal of pollutants from sewage. At the same time, biofuel and biofertilizer are also produced. Therefore, research on methane fermentation of cannery effluents to obtain biogas (alternative biofuel) and digestate (plant growth stimulator) is relevant. The purpose of the work is to study the methane fermentation of cannery effluents with the production of biogas and digestate. The work's task is to study the process of methane fermentation of cannery effluents, determine the intensity of gas generation, study the stimulating effect of digestate on plant seeds. The initial COD of the effluents is 4200 mg O2/dm3, pH 6.8. The research was carried out in a periodic regime, the loading dose was 30 %. Methane fermentation caused a high efficiency of wastewater treatment. The final value of the COD of the effluents was 500 mg O2/dm3. The cleaning efficiency is 88.1 %. The intensity of biogas release was high. Recorded biogas formation of 4 dm3 from 1 dm3 of wastewater. The amount of biogas in terms of the amount of initial pollution: 0.95 dm3/g of CODstart. The amount of biogas in terms of the amount of fermented pollution: 1.08 dm3/g of CODferm. Biogas had a high methane content – 65 – 68 %. Such biogas is used as an alternative biofuel. There is a clear classical interdependence between the reduction of sewage pollution and the release of biogas. Digestate is a valuable fertilizer and seed biostimulator. When seeds were treated with a digestate solution, the growth of roots (by 20 – 27 %), stems (by 21 – 30 %) was accelerated. Germination energy increased by 24.8 % compared to the control experiment.