wet back three pass oil steam boiler
Recently, the State Administration of China's market, the National Development and Reform Commission, Ministry of Ecology Environment jointly issued the "Notice on Strengthening Environmental Protection and Energy boilers" (the "Notice"), put forward specific requirements for environmental aspects of energy-saving boiler work.
"Notice" the implementation of the guidance, "the CPC Central Committee and State Council on the overall strengthening of environmental protection and resolutely fight tough fight pollution prevention advice" and other documents, adhere to safety first, prevention first, the five principles of energy saving, comprehensive management implement energy saving boiler from the production, import, sale, use and other aspects of business to post the main responsibility, and strengthen supervision and management of Eng environmental Protection in the "special equipment Catalog" range of boilers, and comprehensively promote energy-saving environmental governance boiler.
First, across the country, in principle, to a new 10 steam tons / hour of coal-fired boilers and, in key areas (and the surrounding areas of Beijing, Tianjin, the Yangtze River Delta region and Fenwei plain) and the rest of the city built the county level and above New District, in principle, to 35 tons of steam / hour of coal-fired boilers.
Second, the new coal-fired boiler emission concentration of air pollutants key areas need to meet ultra-low emission (6% on the basis of the reference oxygen, soot, sulfur dioxide, nitrogen oxides emission concentration of not more than 10,35,50 mg / m) requirements.
Third, the area reserved execution key boiler air pollutant emission limits or special places more stringent emission standards, 65 t steam / hour coal-fired boiler and above all of the ultra-low emissions and energy transformation embodiments, a low nitrogen gas boiler is substantially complete transformation.
"Notice" also stressed the upgrade boilers with energy and environmental conservation requirements. Boiler units to implement the main responsibility for ensuring that the boiler energy efficiency and emissions of air pollutants meet legal regulations, technical specifications and requirements of the relevant standards in China.
Fourth, for the boilers do not meet environmental requirements, and use shall take appropriate measures for improvement, if after rectification not meet the requirements, be allowed to continue to use.
Fifth, the boiler unit to apply for emission permits in accordance with laws and regulations, and to establish their own monitoring system, strict discipline and preservation of the environment management accounting, timely and relevant departments to prepare and submit emission permits implementation report.
Sixth, the boiler unit to promptly take the initiative to report the boiler equipment obsolete, and apply for cancellation of the boiler use registration shall not be obsolete boilers to move equipment or put into use again.
Steam Gas Gas Desulfurization to achieve excellent results steam oven gas steam oven must sample tests, the thermal conductivity was measured quality of appearance, flash point, viscosity, acid, water, and carbon residue, provided with heat transfer fluids plant proof mass It is consistent with the book, but also provide the basis for future changes in the operation of medium quality monitoring. Means passing the tests of the gas-steam heat transfer fluids using pumps to transfer fluids within the furnace and the injection of hot expander. When pumps heat transfer fluid to the injection system, should check again the furnace, heating equipment, piping system drain valve, drain valve is closed, in order to avoid loss of heat transfer fluids. While the exhaust pipe and the valve opening on the furnace one by one, to exclude air, until a closed gas steam flows. It stops when the oil level gauge appears on the expander injection heat transfer fluids, and then start the circulation pump, for circulating cold. Existing gas steam oven dry dust, do not meet wet desulphurization process of flue gas CWS humidity, water vapor in the flue gas as coal-water slurry up to 36%, some as high as 40% or more water content of coal-water slurry, If we consider only the dust and sulfur dioxide that is not enough. Arts gas wet back three pass steam boiler company after multi-party experts to study, test, develop a dusting product, the successful use of coal-water slurry plenty of water in the flue gas as a carrier, by cooling, reducing condensation, dust and sulfur dioxide capture down, to achieve excellent results gas desulfurization steam oven. The effect of dust reaching the user's satisfaction. Gas welding gas steam oven must be operated by welders holding boiler and pressure vessel certification of welders. Welding dimensions meet the design drawings and process documents, bead height is not less than the base material, the base material with a smooth transition. Gas fuel gas steam oven weld and heat affected zone no cracks, holes, craters and slag. Weld undercut hole deeper than 0.5mm, the total length (the sum of both) is not more than 1/4 of the circumference of the tube, and not more than 40mm. Construction of gas steam oven strict compliance with welding procedures and other relevant standards and regulations, and make construction records welded to record the record.
Why boiler furnace exhaust gas temperature increases heat losses the heat loss is largest in a boiler, furnace 6% is generally fed to the heat, the exhaust gas temperature increasing every 12 ~ 15 ℃, heat losses to an increase of 0.5%. Therefore, the exhaust gas temperature is one of the most important indicators boiler operation. Here are a few reasons may cause the furnace exhaust gas temperature rise: (1) heating surface slagging, fouling. Whether waterwall slagging furnace fouling, or superheater, convection bank, and economizer preheater fouling are due to increased resistance measured smoke, heat deterioration of the cooling effect deteriorates the flue gas, resulting in increased exhaust gas temperature. (2) the excess air ratio is too large. Under normal circumstances, the furnace outlet increases as the excess air ratio of the exhaust gas temperature rises. After the excess air ratio increases, while the amount of smoke increases, the speed increase of smoke, heat strengthening of exiled, but less than the degree of increase in heat transfer gas volume increases more. It will be appreciated as the tobacco rate increased, the time to heat to the flue gas working fluid left the heating surface. (3) leakage factor is too large. Tail shaft furnace and boiler flue negative pressure leakage is inevitable, and provides a heating surface allowed leakage coefficient. When the coefficient of air leakage increases, the influence of the exhaust gas temperature and overfire air coefficient increases similarly. And the closer the leakage furnace, exhaust gas temperature raising effect on the greater. (4) water temperature. When the turbine load is low or high pressure splitting when the heater temperature of the boiler feedwater will decrease. Generally, when the water temperature rises, if the amount of fuel is maintained constant, the temperature difference decreases economizer, economizer heat absorption decreases the exhaust gas temperature rises. (5) the fuel moisture. The fuel in the flue gas to increase the amount of water increases, and therefore the exhaust gas temperature rises. (6) boiler load. Although the boiler load increases, the amount of smoke, the amount of steam to the water, the air amount increases in proportion, but since the furnace exit gas temperature is increased, so that the exhaust gas temperature rises. After the load is increased to increase the furnace outlet temperature, followed by convection heating surface temperature difference increases, an increase in heat absorption, the more so the convection heating surface, the smaller the impact load change of a boiler exhaust gas temperature. (7) The fuel species. When burning low calorific value gas, since the furnace temperature is lowered to reduce the radiation heat transfer in the furnace, the low calorific value gas in a non-combustible components, mainly N2, CO2, H2O more, the amount of flue gas increases, the exhaust gas temperature rise high. Pulverized after burning oil, although oil-fired furnace outlet when the excess air ratio than the coal is low, but the little ash fuel oil, and no larger soot particles, larger ash particles in the flue gas absent the cleaning action of surface heating, convection heating surface more polluting. So bad combustion, often black smoke boiler flue gas temperature. When the tail has means ash ball, since the tail cleaner, the exhaust gas temperature is slightly lower than the burning coal. (8) milling system operation. Bunker has a reservoir of closed milling system is concerned, when the pulverizing system is running, because a portion of the water in the fuel into the furnace, the furnace temperature is reduced and the amount of smoke increases, the leakage into the pulverizing system is running as the primary cold air air into the furnace, to reduce the amount of air flowing through the air preheater to the exhaust gas temperature rises. Conversely, when the exhaust gas temperature is reduced pulverizing system outage.
After the gas-steam circulation pump approach failed for some time to use gas steam oven, it will produce a precipitate. At this point, we need to clean heat transfer oil furnace, but before cleaning, we need to know what kind of sediment, and then cleaned the right way, if the heat transfer oil, grease appears very easy to make the wall thermal resistance increases, will increase the production of energy, gas steam liquidity will deteriorate, production will be reduced, the operating cycle will shorten the life of the device will be. Shorten, which in turn affect production. Some of the more common gas wet back three pass steam boiler deposits are: sulfate, carbonate, silicon and iron. Acid sulfate does not bubbling, since relatively hard sulfates, carbonates decompose at high temperatures, the bicarbonate will dissolve, but the release of carbon dioxide will form an insoluble carbonate salt. When the temperature reaches 300 ~ 400 ℃, hot oil furnace thermally cracking occurs. It will produce carbon deposits on the inner wall and an inner wall, it affects the heat transfer efficiency. Easy to produce oil furnace heat transfer in high temperature environments. Thermal cracking, thermal polycondensation, and its kinematic viscosity increases, the fluidity deteriorates internal oxidation of the oil pipeline, oil conductive accelerated failure, the machine will be damaged, endanger human will be high. Steam oven gas processing cycle pump failure: (1) When the current is below the normal circulating pump, the circulating pump efficiency is lowered, the flow rate is reduced, the fouling of the heating pipe may be blocked, it should be cleaned. (2) circulating pump pressure constant, the current increases, flow decreases. Bad heat transfer fluid, the viscosity increased, should be replaced or regenerated. If the system does not remove water or aqueous decomposition newly heated conductive liquid should be immediately opened exhaust valve to the exhaust gas. (3) circulating pump current is reduced, the pump outlet pressure back to zero, indicating that the pump is not idle. It may be vaporized oil, gas and steam oven measures to find the cause vaporization; if the filter is clogged, the circulation pump should be evacuated and cleaned immediately opens the bypass filter; if the heating fluid contained in the new water or heated water, the system does not exclude the decomposition gas, the exhaust valves should be opened immediately exhausted.