Ammonium bisulfate poisoning prevention wide-temperature-range SCR (Selective Catalytic Reduction) catalyst taking fly ash as matrix as well as preparation method and application thereof

Abstract

The invention discloses an ammonium bisulfate poisoning prevention wide-temperature-range SCR (Selective Catalytic Reduction) catalyst taking fly ash as a matrix as well as a preparation method and application thereof, the catalyst takes porous fly ash as the matrix, and the wide-temperature-range SCR catalyst is attached to the surface of the porous fly ash. The preparation method comprises the following steps: mixing the porous fly ash and the wide-temperature-range SCR catalyst, and grinding to obtain the catalyst. According to the ammonium bisulfate poisoning prevention wide-temperature-range SCR catalyst with the fly ash as the matrix, ammonium bisulfate poisoning can be effectively prevented within a wide temperature range, the use temperature range of the SCR catalyst is effectively widened, the catalyst is suitable for medium-low-temperature SCR denitration, regeneration is easy in the actual use process, recycling of the catalyst can be achieved without shutdown, and the catalyst is environmentally friendly and free of pollution. The method is high in use value and good in application prospect, and has very important significance for effectively improving the flue gas denitration efficiency of a coal-fired power plant. The preparation method of the catalyst has the advantages of simple process, convenience in operation and the like, does not need special equipment, and is easy to realize industrial production.

Description

technical field [0001] The invention belongs to the field of tail flue gas denitrification, and relates to a wide temperature zone SCR catalyst for preventing ammonium bisulfate poisoning with fly ash as a matrix, a preparation method and application thereof. Background technique [0002] Currently, NO in flue gas from coal-fired power plants x , usually using selective catalytic reduction denitrification (SCR) technology for removal, and often in a "high temperature + high dust" arrangement. With the adjustment of the energy structure, coal-fired power units will face heavier peak-shaving tasks, and their low-load operation and deep peak-shaving will become the norm. Using SCR technology to remove NO in flue gas of coal-fired power plant x When using commercial denitration catalysts, such as V-W / Ti-based SCR catalysts, the operating temperature range is 320-420°C. When the coal-fired power unit operates at low load, the SCR inlet flue temperature is lower than the cataly...

AI Technical Summary

Problems solved by technology

For example, catalysts with Cu or Mn oxides as active components have good low-temperature NH 3 -SCR activity, but its active site is easily in SO 2 Severe chemical deactivation occurs due to sulfation in the environment, which ultimately makes this type of catalyst unable to adapt to the treatment conditions of most industrial waste gases

As another example, low-temperature catalysts based on Cu-based molecular sieves have better SO 2 Tolerance, but due to its complicated preparation method and regeneration temperature as high as 650°C, it cannot effectively alleviate the catalyst clogging and poisoning problems caused by ABS deposition, so it is difficult to achieve commercialization in the coal-fired field

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