Denitration catalyst used for wide temperature windows, and preparation method thereof

Abstract

The invention discloses a denitration catalyst used for wide temperature windows. By mass, 100% of the denitration catalyst used for wide temperature windows comprises 30 to 80% of TiO2, 10 to 50% ofZrO2, 0.5 to 1.5% of V2O5, 1 to 3% of CeO, 3 to 7% of WO3, and 2 to 5% of SiO2. The invention also discloses a preparation method of the denitration catalyst used for wide temperature windows. The preparation method comprises ten steps disclosed in the invention. At 250 to 420 DEG C, the denitration efficiency of the denitration catalyst is capable of reaching 90% or higher; nanometer zirconia isadded as a part of carriers, so that catalyst heat resistance is improved, sintering risk of the denitration catalyst in operation is reduced, the denitration catalyst possesses high efficiency denitration performance even at 250 to 300 DEG C, and low-load operation requirements are satisfied.

Description

technical field [0001] The invention belongs to the field of preparation of denitration catalysts, in particular to a denitration catalyst used in a wide temperature window and a preparation method thereof. Background technique [0002] Nitrogen oxides (NO, NO 2 and N 2 O) is one of the main pollutants in today's environmental pollution. These nitrogen oxides can cause a series of problems such as photochemical smog, acid rain, ozone layer depletion, and greenhouse effect. In my country, 70% of nitrogen oxide emissions come from coal combustion, and thermal power plants are large coal-fired households. Therefore, how to effectively control the nitrogen oxide emissions of thermal power units is the focus of attention of the thermal power industry and even the whole country. [0003] With the promulgation and implementation of GB13223-2011 by the country, a large number of thermal power boilers are equipped with SCR denitration systems, and the denitration catalyst is the co...

AI Technical Summary

Problems solved by technology

[0003] With the promulgation and implementation of GB13223-2011 by the country, a large number of thermal power boilers are equipped with SCR denitration systems, and the denitration catalyst is the core component. However, the most common commercial SCR denitration catalyst is vanadium tungsten titanium type, and its active component is V 2 o 5 -WO 3 / TiO 2 , the active temperature window is only in a small range of 300-420°C, and the catalytic activity is extremely poor in the middle temperature range (250-300°C)

[0004] For a specific device, the design temperature range of the catalyst is slightly changed. Usually, the flue gas temperature at the economizer outlet is designed according to the normal load of the boiler. Temperature requirements for denitrification devices

At present, thermal power units are basically involved in peak regulation, which causes boilers to often operate in the low-load stage. When the boiler is in the low-load stage, the flue gas temperature at the economizer outlet is low, and the flue gas temperature is too low to meet the continuous operation of the denitrification system. , stable operation requirements

The existing technology is no longer suitable for the requirements of the latest emission indicators of nitrogen oxides in power plants. At the same time, when the load is low for a long time, due to the low efficiency of the catalyst, it will cause NH 3 The escape rate is high, and ammonium bisulfate is produced, which leads to the blockage of the air preheater

Images