Increasing the efficiency of the boiler house using screw expansion machines

Abstract

THE PURPOSE. Improving the efficiency of the boiler house. Development of a scheme for the introduction of screw expansion machines (SEM) into the thermal scheme of a boiler house. Calculation of the main technical characteristics of SEM and network heaters. Calculation of the economic effect and assessment of the feasibility of using energy-saving technologies in an industrial enterprise.METHODS. The work uses methods of computational mathematics, the theory of heat and mass transfer, methods of technical and economic calculations in the energy sector, and thermodynamic analysis of power plants.RESULTS. The article presents a variant of improving the efficiency of the boiler shop in Neftekamsk by putting into operation the steam boilers DDVWT, which are mothballed, and introducing screw expansion machines. It is proposed in the non-heating period (April - September) to turn on steam boilers to generate steam. The steam will pass through the SEM, lowering its pressure to that required for network heaters for subsequent heating of water for hot water supply. At the same time, electricity will be generated on the SEM generators, which will be transmitted to the auxiliary tires of the boiler house. According to the results of calculations, two SEM with a capacity of 700 kW each, as well as three network heaters, were selected for the installation. With the considered inclusion of additional steam boilers and SEM in the non-heating period of the year, the generated electricity will fully cover the costs for the auxiliary needs of the boiler house. The payback period of the project will be 5 years.CONCLUSION. The results of technical and economic calculations show the feasibility of introducing SEM into the thermal scheme of the boiler house as an energy-saving measure.