Study On Properties Of Energy Saving And Environment Protection Of Condensing Gas-fired Boiler

In China, environmental protection is being emphasized much more than ever, the boilers that use natural gas, which is clean energy, are replacing the coal-fired boilers that have been used widely in heating systems. The exit flue gas temperature of a natural gas-fired boiler is usually as high as 130-200°C . An much greater amount of water vapor is contained in the flue gas of a natural gas-fired boiler because of higher hydrocarbon content of natural gas, therefore, the latent heat entrained in the water vapor is discharged out of the boiler envelope, which leads to a high heat loss. A so-called condensing boiler can be used to reclaim the latent heat to the utmost extent. Since the first condensing boiler was invented in 1970s, many countries have been involved in the development of condensing boilers and the experiment research of pertinent processes. At present, The study on condensing gas-fired boiler is starting,our country will adopt condensing gas-fired to improve the efficiency of energy and reduce contamination.First,the thesis concludes the calculational method of heat loss of exit gas.Study the relation between heat loss of exit gas and different gaseous fuels,exit gas temperature,excess air coefficient,air temperature,air humidity and heating system,and obtains the relation curve. Establishs the exergy analytical equation, compare exergy efficiency and heat efficiency between condensing gas-fired boiler and ordinary gas-fired boiler.Next,the thesis studys effect on oxygen-enhanced combustion giving the energy saving property of condensing gas-fired boiler,obtains the relation curve between heat loss of flue gas and oxygen-enhanced quotient. Analyse the effect on oxygen-enhanced quotient to heating seasonal efficiency and power of exhaust fan. studys effect on oxygen-enhanced combustion giving running economy, obtains the relation curve between economical natural gas-oxygen price ratio and several typical oxygen-enhanced quotient.Finally, the thesis analyse the condensation decontaminate mechanism, brings forward the calculational model on maximal theoretical volume concentration...