TECHNOLOGIA EWHR ODZYSKU CIEPŁA I REDUKCJI EMISJI W KOTŁACH

High temperature and moisture of the exhaust gas cause significant losses in boiler operation. This encourages the search for ways to increase the efficiency by reducing these losses. The most effective method to increase boiler efficiency is to recover latent flue gas heat. In this case, the modernized boiler becomes a condensing boiler. The paper presents the EWHR (Ecological Waste Heat Recovery) technology. The first part presents an industrial application of EWHR installed on the bypass of the flue gas duct behind three coal-fired flame-tube steam boilers with a capacity of 3 Mg/h each. The second part describes modernization concerned two natural gas-fired flame-tube steam boilers with a capacity of 30 Mg/h steam. Indicators characterizing energy performance (including improvement of installation efficiency), reduction of emissions and financial assessment of the modernized installations are given. The obtained results prove that EWHR technology significantly increases the energy efficiency of the system and reduces the emissions of dust and harmful gases, including SO₂ and CO₂. The parameters characterizing the energy performance were calculated on the basis of the relevant indicator for assessing the improvement of energy efficiency. The paper also presents spreadsheets for the initial self-assessment of the reduction of costs incurred for the operation and emission fees of boilers modernized according to the described technology.