A condensing boiler can condense the water vapour in the flue gases and withstand the corrosive and acidic qualities of the flue gas condensate. Although most boilers can condense the flue gasses, only boilers that have heat exchangers constructed from materials able to withstand the corrosion should be used in condensing application. Condensing boilers with primary and secondary heat exchanger do not work well as they are not able to fully condense and defeat the purpose of using a condensing boiler. Also, boilers with this arrangement are prone to condensation in the primary heat exchanger at lower firing rate which can cause damage to the heat exchanger.
Shell boilers may be defined as those boilers in which the heat transfer surfaces are all contained within a steel shell. Shell boilers may also be referred to as "fire tube" or "smoke tube" boilers because the products of combustion pass through the boiler tubes, which in turn transfer heat to the surrounding boiler water.
The gas-fired boiler has the wonderful energy-saving effect and environmental protection performance. The energy-saving effect of the gas-fired boiler is realized by many boiler parts.
Facing the aggravation of environmental pollution, many industries have been required to meet the pollutant emission standards. As a kind of thermal energy equipment, the boiler has high pollutant emission. However, the implementation of environmental protection policies has prompted enterprises to use energy-saving and eco-friendly boilers. Therefore, let us talk about the characteristics of the gas-fired condensing boiler here.
With the industrial innovation and the advance of science and technology, steam engine is replaced by gas-fired boiler that is a kind of more energy-saving heat production machine. There are three main usages of gas-fired boiler that we need to know in order to better understand the benefits that gas-fired boiler brings to us.
The condensing boiler burns carbon-based fuel with oxygen in order to produce steam and carbon dioxide. The gases that escape this process (through a chimney) as exhaust are called flue gases. The major advantage is that they offer up to a 90% improvement in terms of efficiency when compared to standard gas boilers. Overall, condensing boilers are considered much more efficient in contrast to non-condensing gas boilers, a major consideration for any business running on a budget.
This is because, under normal circumstances, the exhaust temperature of the boiler cannot completely condense the water in the flue gas, and the difference between the low calorific value and the high calorific value is mainly in the part of the latent heat of vaporization, so the low heat is used. The value is calculated to reflect the true efficiency of the boiler. However, there will be some special circumstances. For example, if the boiler is a condensing boiler, the calculation of the condensed water portion should be calculated using the high calorific value.
A fire tube steam boiler is a boiler where the combustion gases from the burner are channeled through tubes that are surrounded by the fluid to be heated. The boiler body is the pressure vessel and contains the fluid. In most cases, this fluid is water that will circulate for heating purposes or become steam for use in processing.
Each set of tubes through which the combustion gas passes, before making a turn, is considered a "step". Consequently, a three-step boiler will have three sets of pipes with the outlet located at the rear of the boiler.
