The process synthesis and optimization methods used in this work include simulation of biomass gasification, hydrogen and synthetic natural gas production, and jet fuel production via a Fisher Tropsch unit. An energy integration approach, carried out by the OSMOSE platform, allowed minimizing the energy requirement of the integrated systems and prioritizing the use of waste heat at high temperature for industrial applications. In this way, the low grade waste heat can be reutilized to supply a nearby district heating network or a supercritical CO2 cycle to generate surplus power. In addition, the implementation of a seasonal power-to-gas approach, including electrolysis, methanation, carbon abatement technologies, required the management of the time-varying demand and supply. To this end, a multi-time approach, using seasonal profiles of energy demands and prices, has been used to minimize the capital investment of the seasonal energy storage systems (e.g. liquids tanks). An industrial plant is represented as the main energy system to be heated by the use of renewable energy resources, whereas the city operates as the heat sink thereof. Accordingly, the goal was to reduce the valuable waste heat released to environment during the summer period and store it, so that it can be used to supply the energy needs in the winter, along with biomass, to the SAF production plant. . Thanks to its versatility, the combination of different energy technologies has been applied to defossilize industrial heating applications, whereas producing value-added fuels. A typical central European zone city is considered for the assumption of the thermal loads of district heating network, including domestic hot water, space heating, air conditioning and refrigeration. The integration with the surrounding population has been achieved implementing a novel CO2 district heating network, which can be used to distribute heat and upgrade the low-grade waste heat released by the industrial production processes. As a result, the fossil emissions could be virtually avoided and a production of up to 100000 barrel of synthetic aviation fuel per day has been achieved. Also, the installation of a CO2 management system, composed of liquefaction, storage and recompression units allowed injecting biogenic CO2 (120EUR/t), which translated to higher economic benefits of the integrated energy system.