| Abstract [eng] |
The Master’s Final Thesis examines the efficiency of biofuel cogeneration plants and its determining factors, and the equipment capable to reduce the thermal losses arising from the specific features of fuel. The share of water in biofuel often constitutes 50% of total biofuel mass; therefore, a large quantity of water vapour exists in combustion products. The condensing economizer is capable to accept only part of heat from smoke; the remaining low-potential heat is simply removed through the chimney. The heat recovered from smoke may significantly improve energetic and economic indicators of a plant. The main task of the Thesis is to analyze the benefit provided by the heat and mass exchange regenerator, and to justify it by energetic and economic calculations. The Thesis thoroughly examined the thermodynamic efficiency of biofuel cogeneration plants and their dependencies on various factors. With the help of the software, a spatial model of the heat and mass exchange regenerator was developed, and strength calculations were performed, which enabled the accurate estimate of the investment costs of the regenerator. The performed energetic and economic calculations justified the benefit provided by regenerative system. The fuel costs of the analyzed plant with regeneration system decreased to more than 15%, the thermal losses through the chimney decreased to about 15%. The investment costs of the low-capacity biofuel cogeneration plants are high; therefore, a large part of the costs consists of the loan repayment, in consequence of which the profit of such plants is not large; and, in some cases, the work of the plant may also be loss-making. The regenerative system may ensure the efficient and profitable work of the plant without large investments. |
