(LN) WNS series full-automatic oil (gas) steam boiler adopts corrugated furnace liner, spiral smoke pipe, three return flue gas and full wet back structure. The fuel burns in the furnace with slight positive pressure. The high temperature flue gas enters the first threaded flue tube bundle through the reburning chamber, enters the second tube bundle after turning 180 ° through the compression flue box, and discharges into the atmosphere after convection heat transfer. Based on the design idea of centrosymmetric three return steam boiler, a large capacity three return steam boiler is designed. The biggest characteristic of this kind of boiler: all pressure components and drum
Central symmetry, the boiler adopts full wet back structure, with a large inner tube and fire box structure, which is conducive to provide sufficient radiation heating surface. The convective heating surface consists of tube bundles with second and third return paths. The front tube sheet of the reburning chamber is connected with the furnace liner, and the back tube plate of the cylinder body is connected by the back pulling brace. The front smoke box is composed of the second return and the third return, and the temperature of the smoke is lower than 500 ℃. Therefore, the structure of the front smoke box is made of fire-resistant and thermal insulation materials with light structure. This kind of boiler design mainly considers the boiler maintenance and stability principle. The water mixing device is set at the inlet of boiler feed water. The feed water washes the flue pipe bundle first, and then contacts with the furnace bladder, which improves the water temperature of the feed water contacting with the furnace bladder. The phenomenon of local subcooled boiling is avoided. The steam boiler reaches the maximum vaporization space, and the reasonable and advanced steam water separation device is used, so the main steam quality is quite stable.
In addition, the heat transfer of flue gas in the furnace is enhanced, and the heat transfer between the flue gas and the flue gas in the furnace is enhanced. The process measures of pre expansion, eliminating the gap between tube and tube sheet, and then welding, effectively prevent possible corrosion and crystallization in high temperature zone.
The scale alarm function (optional) can monitor the water quality of the heating surface in real time. If it exceeds the standard, it will alarm automatically.
The exhaust gas temperature of a fully condensing gas steam boiler is higher than that of an ordinary boiler. The water steam is overheated and exists in the gaseous state. If the exhaust gas temperature is lowered to a sufficiently low level, the water vapor in the flue gas will condense and the latent heat of vaporization of condensate can be utilized. The majority of natural gas is methane (CHA), and the water transport dimension steam accounts for more than 18% of the combustion products. After combustion of 1 cubic meter of natural gas, 1.55kg of water vapor can be generated. In the available heat energy of boiler exhaust gas, the latent heat of steam vaporization accounts for a large share, about 3700k / Nm3, accounting for more than 10% of the low calorific value of natural gas. 80-85% of the heat generated by ordinary boiler combustion is transferred to the working fluid, Heat dissipation accounts for about 1%, and according to different fuels, the maximum exhaust gas loss can be as high as 20-30% of the high-level calorific value; for ordinary natural gas boilers, the heat loss taken away by steam accounts for 55% ~ 75% of the total exhaust loss; if the exhaust gas temperature is reduced to above the dew point of steam, the boiler efficiency can be increased by 2 ~ 5%, More than 15% of the latent water can be recovered. By condensing the water vapor in the flue gas, the boiler which can fully absorb the exhaust gas, heat and latent heat of steam vaporization is called condensing boiler. The purpose of high-efficiency heat recovery and heat release of the condenser in the tail of the pressure boiler is to improve the efficiency of the heat recovery and heat release of the condensers in the pressure condensers.