The system of complex recovery of low-potential secondary energy in the thermal technology scheme of pulp and paper production

RELEVANCE. Pulp and paper production is an energy-intensive industry with significant amounts of unused secondary energy resources (REM), especially low-potential heat (40-80°C). In the context of growing energy efficiency and environmental requirements, the recovery of these wind turbines from sources such as wastewater and recycled water, ventilation emissions, and heat cooling of intermediates is becoming not just a promising area, but an urgent necessity. This makes it possible to reduce fuel consumption, energy consumption and harmful emissions, thereby increasing the competitiveness of enterprises. purpose. The aim of the study is to increase the energy efficiency of a complex industrial heat and technological scheme of pulp and paper production using methods of structural and thermodynamic analysis. These analysis methods make it possible to objectively assess the potential of recycling secondary energy resources and select the most effective schemes of wind power recovery systems. METHODS. Exergetic analysis revealed significant unused heat losses in pulp and paper production, in particular, in drying plants with an efficiency of only 46.9%. It has been revealed that the flows of exhaust air, waste and recycled water, and the upper product of the columns have the greatest potential for recovery. Their utilization by means of heat pumping units can significantly increase the energy efficiency of production, reducing energy costs and thermal pollution of the environment. results. Thermodynamic analysis revealed significant unused losses in key production streams (waste air, wastewater and recycled water. the top product of the columns). A system for their recovery using heat pumping units (TNUS) has been developed, which makes it possible to increase the total energy utilization of the system from 17.88% to 92.58%. The introduction of TNW provides significant savings in thermal energy and reduces the environmental burden of production. conclusion. To solve this problem, a comprehensive heat recovery system based on thermal transformers – heat pump installations has been developed. Its implementation will make it possible to utilize 10.13 MW of thermal capacity from waste streams, increasing the overall energy efficiency of production.

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