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Product Introduction to SCR Denitration Equipment I. Product Overview: Regarding the currently widely used SCR denitration technology, SCR denitration equipment is mainly divided into two types: AN-type SCR and urea-type SCR. Both of these methods utilize the reduction capability of An to convert NOX (mainly NO) into N2 and water, substances that have little impact on the atmosphere, under the action of a catalyst. The SCR denitration system involves injecting ammonia gas or some other suitable reducing agent into the flue gas upstream of the catalyst, where the catalyst is used to convert NOx in the flue gas into nitrogen gas and water. In typical designs, liquid anhydrous ammonia or an aqueous solution of oxygen and ammonia is used; regardless of the form in which it is used, the ammonia first has to be vaporized, after which it is mixed with dilute air or inert gas, and finally injected into the flue gas upstream of the SCR reactor through ammonia injection grids. II. Product features: The operating temperature range of the SCR catalyst is 300–400 °C; it is generally installed between the economizer and the air preheater in boilers. Therefore, in the flue gas denitration systems of coal-fired boilers, the SCR catalyst operates in an environment with high levels of dust. The SCR flue gas denitration technology can achieve a denitration efficiency of over 90%, making it a mature and reliable method for denitration. Along with the SCR denitration efficiency, it is also necessary to control the NH3 escape rate and the SO2 conversion rate to ensure the stable and continuous operation of the SCR system. The uniformity of flue gas flow, the uniform mixing of NOX and NH3 in the flue gas, and the uniformity of the flue gas temperature field are key factors affecting denitration performance and must be taken into account in the design. III. Working Principle: SCR Denitration: Selective Catalytic Reduction is a method in which, with the help of a catalyst, specialized companies use a reducing agent such as NH3 to react “selectively” with NOx in flue gas, thereby producing non-toxic and pollution-free N2 and H2O. The term ‘selectivity’ refers to the fact that, during the denitration process, the catalyst selectively reduces NOx to nitrogen, while SO2 in the flue gas is only slightly oxidized to SO3. This is what is meant by selectivity. Without the addition of a catalyst, the chemical reaction between AN and nitrogen oxides occurs at a temperature of 900°C. If AN is added, part of it decomposes at lower temperatures; with a catalyst, the reaction temperature can be reduced to 320–400°C. Catalyst 1 is a mixture of V2O5 and W2O3 based on TiO2, with the specific formulation to be determined according to flue gas parameters. This article is excerpted from SCR denitration equipment: http://www.btshhb.com/Product/6498704852.html