How to Evaluate Steam Boiler Efficiency

The efficiency of a steam boiler should be an important part to evaluate the steam boiler cost because the annual cost of fuel can easily be two to three times the installed cost of the equipment. There are many efficiency should to take into consideration when purchasing a steam boiler such as thermal efficiency, combustion efficiency, fuel-to-steam efficiency.
While the terms efficiency and thermal efficiency are not meaningful for comparing one boiler to another, the terms “combustion efficiency” and “fuel-to-steam efficiency” are. Of these, fuel-to-steam efficiency is the most significant, but it is difficult to measure or calculate in real-world situations. Therefore, combustion efficiency, which can be easily computed using a combustion gas analyzer, is, frequently, used for performance comparison purposes.
The efficiency of a steam boiler can be calculated by dividing the energy going into the boiler by the resulting energy output of the boiler. To directly measure the efficiency of a steam boiler, measuring the energy input to the boiler and its subsequent energy output is necessary.

The measurements will vary depending on the type of fuel used and the boiler being correctly calibrated. The overall efficiency of a boiler depends upon the efficiency of its combustion process, the boiler's thermal efficiency and its fuel-to-fluid efficiency. All three of these aspects of a boiler's functionality must be considered when assessing the overall efficiency of a steam boiler. That the boiler maintains an accurate control of the internal air supply is necessary for achieving greatest possible efficiency. If too much air is allowed inside the boiler, it will have a cooling effect as it carries away some of the heat produced, and if there is too little air, the combustion process will not be complete, and smoke will be produced from any resulting unburned fuel. The effectiveness of the transition of heat from the point of combustion to steam is also key to a boiler's efficiency, and any heat that escapes the boiler in the transition process will add to the inefficiency of the overall process.
ZG Boiler is the steam boiler manufacturer in China with more than 70 years’ history and the steam boiler efficiency in our company is high and the steam boilers’ specific combustion efficiency are as following:
WNS Series Oil & Gas Fired Boiler: 98～99%
SZS Series Oil & Gas Fired Boiler: 98～99%
Oil & Gas Power Plant Boiler: 98～99%
Chain Grate Boiler: 98～99%
CFB Boiler: 95～98.5%

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