Post-combustion plant with downstream 3-fold waste heat utilisation
As general contractor, Birk supplies a ready-to-operate thermal afterburning plant / thermal exhaust air purification plant in horizontal design to a long-standing customer from the supplier industry.
The post-combustion plant / exhaust air purification plant was designed for a raw gas volume flow of 5000 mn³/h from the combination of the exhaust gases or exhaust air from up to four upstream industrial drying plants. The firing plant is equipped with the latest burner generation of our self-developed industrial firing plants of the type "multifire" - for the largest possible output control range for raw gas volume and firing medium, best clean gas values and lowest energy consumption. In addition, with this burner type it is possible to feed the condensates resulting from a production process in a volume flow of up to 80 l/h simultaneously into the ongoing post-combustion process via the flue gas cleaning system.
The plant has 3 downstream heat recovery processes from the outflowing clean gases. In the first downstream process, the raw gases are preheated. The preheating of the raw gases to an inlet temperature of approx. 465°C in the afterburning process results in a considerably lower primary energy requirement for the operation of the combustion plant at thermal afterburning. In the subsequent second and third processes for further primary energy savings, the afterburning system is equipped with two independently operating waste heat recovery systems for thermal oil generation and hot water generation.
The further addition of the heat recovery systems for thermal oil and hot water production to the thermal afterburning system results in an energy-optimal overall concept for the entire system with an energy recovery of approx. 95%. The thermal oil plant is designed for exhaust gas temperatures of approx. 580°C, which makes it possible to recover more than 600kW of heat output at a volume flow of approx. 5000 m³/h. The thermal oil plant is designed for exhaust gas temperatures of approx. 580°C, which makes it possible to recover more than 600kW of heat output at a volume flow of approx. 5000 m³/h. The thermal oil plant is designed for the production of heat at a volume flow of approx. 5000 m³/h. The subsequent hot water system is designed for exhaust gas temperatures of approx. 290°C, which makes it possible once again to recover more than 380 kW of heat output at a volume flow of approx. 5000 m³/h. The system is designed for a temperature of approx. 290°C, which makes it possible to recover more than 380 kW of heat output at a volume flow of approx. 5000 m³/h.
The scope of the system in turn included the entire flue gas supply and discharge by means of independent flue gas systems from the outlet raw gas heat exchanger via the tube bundle of the respective waste heat utilisation system back into the chimney clean gas pipe - naturally including all necessary thermal insulation measures for further energy savings. The independent exhaust air volume flow control of the heat recovery system is guided and controlled in such a way that there is no influence whatsoever on the upstream pressure control processes in the exhaust air cleaning system.
In order to meet the increased internal noise emission requirements, the afterburning system and the waste heat recovery systems are equipped with a comprehensive noise reduction package, which also includes the fans. The entire control technology based on the fail-safe Siemens S7 industrial controls is also included in the scope of supply.