Selective Catalytic Reduction(SCR)

The SCR technology with the high denitrification efficiency and the most promising market, has become the mainstream technologyof international thermal power plant NOx emission control,widely usedinthe United States, Germany, Japan, Austria and other countries. Selective catalytic reduction (SCR) denitrification efficiency is up to 90% or more.
       The SCR technology of LantianQiushiwith independent intellectual property rights has been successfully applied to 1000MW generating units. Typical SCR process is mainly composed of denitrification system and reductant storage and transportation system, wherein the denitrification system is composed of spray ammonia mixing system, SCR reactor, catalyst and flue gas bypass.         

The ammonia gas prepared by the reductant storage and transportation system is sent to the ammonia / air mixer, mixed with air and sent to the SCR reactor, react with the nitrogen oxides in the flue gas under the action of the catalyst to form nitrogen and water. Thusthe purposeof removing nitrogen oxides is achieved.

The reductant may be prepared from liquid ammonia, aqueous ammonia or urea. The urea-ammonia method is the most safe and the highest total cost of investment and operation. The liquid ammonia-ammoniamethod is the lowest cost of investment and operation, but with higherpressure for the storage of pure ammoniaand high safety requirement. The aqueous ammonia-ammoniamethod isbetween the above two methods.

The core of the SCRtechnology is the homogeneityof internal flow field, directly affect the denitrification efficiency and catalyst life. At present, the FLUENT numerical model and the physical model test are used to optimize the internal flow field of the SCR system to ensure the realization of the performance index.

Technical Features:

1. With zoning spray grille, the homogeneityof internal flow field is promised from the technical source, and partition control is realized.

2. According to the actual situation of each condition, the internal flow fieldrealizes optimum through with FLUENT numerical model and physical model test, so as to ensure denitrification efficiency, reduce ammonia escape rate.

Main Process Flow Diagram