wns gas steam boiler in india

WNS oil gas fired horizontal wns steam boiler in india

Trust The horizontal boiler Experts at ZG Boiler

As one of Beijing's air pollution emission standards of the most demanding urban, environmental control is very strict. Beijing primary school campus Emerald City as one of the cradles of socialist culture successor, in terms of the quality of students' learning environment is put emphasis on one hundred percent. October 2017, Beijing primary school campus Emerald City with my company, signed a two Thalia T6 series vacuum hot water boiler for winter heating use.

Several problems into a coal-fired boiler fuel gas boiler fired boilers changed several issues should be noted that the fuel gas boiler: fuel oil (l) high temperature corrosion of the fuel used in the boiler, containing an organic salt of a metal element as sodium, vanadium class, after combustion of the low melting point eutectic oxide crystals, generally of about 600 ℃, or even lower. These oxides sublimation at a high temperature furnace, then condensed in a lower relative temperature of the heated surface to form a high temperature corrosive fouling. Is characterized by high temperature corrosion: the metal began to appear at temperatures in excess of 580-620 deg.] C, the higher the temperature, the faster the etching. High temperature corrosion measures to prevent: l) the use of additives. Mainly magnesium, calcium oxide, hydroxide or dolomite (CaC03, MgCO3) and the like, these additives can generate a high melting point compound with the component acting in a high temperature fouling, the fouling becomes loose and shape, so as to avoid or mitigate high temperature corrosion. 2) use high temperature materials with good corrosion resistance, high temperature corrosion resistant chromium steel is better than the nickel-chromium steel. 3) coated with a protective film. Susceptible to corrosion in high temperature heating surface ceramic surface coating, a silicon carbide or silicon nitride special coatings, the heated surface may be aluminized other treatment to improve its high temperature resistance. 3) coated with a protective film. Susceptible to corrosion in high temperature heating surface and other surface-coated ceramics, silicon carbide, silicon nitride, or special coatings, the heated surface may be aluminized other treatment to improve its high temperature performance rot cloud. (2) low temperature corrosion in fuel sulfur generated during the combustion S02, since the fouling atomic oxygen present in the furnace and the convection heating surface and catalytic oxide film, SO2 is further oxidized to S03. S03 and H2S04 vapor in flue gas generated in conjunction with, the dew point of the flue gas containing the sulfuric acid vapor is greatly increased, when heated wall temperature below the dew point of sulfuric acid vapor will condense on the walls, and corrosion of the metal wall. Usually low temperature corrosion It occurs at the end of the air preheater of the boiler. Thus when burning high sulfur fuel, care must be taken to prevent low temperature corrosion. Prevent low temperature corrosion measures are: 1) low oxygen combustion. When the excess air at the outlet of the furnace lag coefficient down to 1.10 or less, for sulfur of the fuel oil used, the dew point of the flue gas will be significantly decreased, so as to avoid or mitigate low temperature corrosion. 2) use of additives. Sprayed into the furnace or flue additive in the curb generation of SO3 and to reduce the flue gas dew point temperature. Common additives solid (dolomite, limestone, magnesium oxide, and some special compound), the liquid (aqueous magnesium chloride solution, some oil soluble magnesium, calcium, zinc naphthenate compound) and a gas (ammonia gas, ammonia, three different ring) three categories. 3) raising the thermal wall temperature, so that it is higher than the dew point temperature of flue gas. Commonly used methods are: hot air recirculation inlet temperature of the air preheater increase; the installation of the heater core, air is heated by steam, a low temperature air preheater horizontal structure, the level of a horizontal pipe line is arranged an air preheater , the air flow in the pipe, the pipe between the smoke flow, erosion due to the lateral wall of the flue gas, the flue gas side heat transfer coefficient is increased to increase the wall temperature, more generally vertical wall temperature of the air preheater increase 20 ~ 25 ℃. 4) corrosion-resistant materials or corrosion resistant coating materials include glass, ceramics and the like; an anti-corrosion coating and had tried to enamel-coated surfaces like special steel anticorrosion paint. 5) timely sootblowing operation, and therefore should be a reasonable arrangement sootblowers. Fire and explosion of fuel failure (3) heating surface of the tail or incomplete combustion of atomized droplets gather in the tail of the heating surface, when it reaches ignition or explosion conditions, i.e., ignition and explosion may occur. The tail heating surface fouling aggravated by the possibility of aggregation of the oil droplets. Therefore, when coal-fired boilers into oil-fired boiler, burner should be correct and rational selection and delivery, and strictly develop from the induced draft fan. Rules and procedures for shutdown and normal operation to ensure good fuel atomization, with the wind reasonable. At each of the heating surface is arranged to be reasonable sootblowers. (4) determining the dew point temperature of flue gas is determined dew-point temperature of the flue gas has practical significance for the design and operation of flue gas dew point temperature factors influence mainly sulfur fuel ink, excess air coefficient, water vapor in the flue the amount of sulfur / cement ratio and combustion.

If you know a little about chemistry, you may know that the sulfur content of oil and coal is roughly equal, but ask what low-temperature corrosion of oil-fired boilers is much more serious than coal-fired boilers, for two main reasons:

1. 90% of ash in coal-fired boiler, especially coal powder furnace, is taken away by flue gas, sulphuric acid steam formed in flue gas is absorbed by fly ash in flue gas, so that sulfuric acid vapor in flue gas is reduced, and about half of sulfur remains in ash when coal is burned. When the oil is burning, the sulfur content in the fuel almost all changes to the ash in the SO2, fuel, the fly ash in the flue gas is very little, and the adsorption ability to the sulphuric acid vapor in the flue gas is very weak.

2. The hydrogen content of oil in the oil-fired boiler is about 11%-12%. The combustion of each ton of fuel oil can produce about 1 ton of water vapor, and the partial pressure of steam in the flue gas is higher than that in the case of coal-burning.