Wood biomass cogeneration plant

The plant used energy from conventional external sources, even though it could have used wood residues from its production process. Before our intervention, electricity was supplied by and paid to HEP, while heat was provided by a biomass boiler, resulting in higher operating costs.

The key technical challenge was to design a system that works reliably with wood chips of variable humidity and granulation, as they are produced in the actual production process. We chose a movable grate combustion chamber, which ensures stable combustion and fuel flexibility even at elevated moisture content. The combustion process has two phases: primarily on the grate, secondarily in a vertical chamber, ensuring minimal emissions and high fuel utilisation.

Thermal energy from the boiler is transferred via a thermal oil system to the ORC turbogenerator, where it is converted into electricity. The remaining thermal energy is distributed via a heating pipe to existing consumers in the plant. The entire system, from biomass transport to production on the turbogenerator, is monitored and managed by the SCADA system.

The plant has established an integrated energy system that converts wood waste generated by its own operations into heat and electricity. It has been in continuous operation since 2021, with 7,800 annual operating hours, resulting in a significant reduction in dependence on external energy sources and in greenhouse gas emissions.