| dc.description.abstract | Abstract
Most smoke-tube boilers commonly utilize heavy oil as fuel, resulting in the production of high-temperature, high-pressure steam, carbon dioxide emissions,and negative impacts on air quality and global warming. This study aims toexplore the installation of fuel economizers in small and medium-sized smoketube boilers to enhance boiler thermal efficiency, promote energy conservation,and reduce carbon emissions.
For this investigation, 30 sets of smoke-tube boilers were selected, with 15 sets lacking fuel economizers while the remaining 15 sets were equipped with them. The boiler thermal efficiency was assessed using the boiler-efficiency
heat-loss method based on test records. Factors influencing boiler efficiency were compared, and the benefits of energy conservation and carbon reduction were evaluated. All boilers employed identical No. 6 heavy oil as fuel, ensuring
similarity in average total heat input. The most significant factor affecting total heat loss in the boilers was found to be exhaust-gas heat loss, with an average difference of 390 kcal/kg observed between boilers with and without fuel
economizers. Boilers without a fuel economizer exhibited an average thermal efficiency of 89.70%, complying with government regulations that mandate efficiency levels of 87-90% and above. However, the average exhaust-gas temperature of each boiler exceeded the government-specified limit of below 200°C, measuring 230.7°C. Boilers equipped with a fuel economizer demonstrated an average thermal efficiency of 93.68% and a lower exhaust-gas temperature of 145°C, surpassing the government standard.
The boilers analyzed in this study had an evaporation capacity of 6 tons per hour. The cost of installing a fuel economizer was estimated at 1.2 million NT dollars, resulting in an annual fuel saving of approximately 36 tons and a reduction of about 111 tons in carbon emissions. Considering a carbon tax rate of 100 NT dollars per ton and the fuel savings of approximately 780,000 NT dollars, the investment in a fuel economizer could be recovered within one year and seven months.
Keywords: Smoke tube boiler, Fuel economizer, Boiler thermal
efficiency,Energy saving and carbon reduction. | en_US |