Shandong Mingsheng Environmental Protection Technology Co.,Ltd
SDS sodium-based dry desulfurization + scr medium and low temperature denitrification technology process principle and characteristics-Industry News-Shandong Mingsheng Environmental Protection Technology Co.,Ltd

Shandong Mingsheng Environmental Protection Technology Co.,Ltd

Add:Chajiu Industrial Park, Zhangqiu District,Jinan City, ShanDong Province, China

SDS sodium-based dry desulfurization + scr medium and low temperature denitrification technology process principle and characteristics


1. SDS process principle


The SDS dry deacidification injection technology is to spray high-efficiency desulfurizer evenly into the pipeline. The desulfurizer is heated and activated in the pipeline, and the specific surface area increases rapidly. Physical and chemical reactions occur in full contact with acidic flue gas. SO2 in the flue gas And other acidic substances are absorbed and purified.


Its main chemical reaction is:


2NaHCO3 +SO2+12O2 Na2SO4 +2CO2+H2O

2NaHCO3 +SO3 Na2SO4 +2CO2+H2O


Its main reaction with other acidic substances (such as SO3, etc.) is:


NaHCO3 +HCl NaCl +CO2+H2O



2. SCR denitrification process principle


Selective catalytic reduction (SCR) uses ammonia as a reducing agent in a reactor equipped with a catalyst to remove nitrogen oxides. The NOx in the flue gas is generally composed of about 95% NO and 5% NO2 by volume . NOx is converted into molecular nitrogen and water vapor through the denitrification reaction. The main reaction equation of SCR is:

4NH3+4NO+O2 4N2+6H2O

4NH3+2NO2+O2 3N2+6H2O


3. Process characteristics


3.1 Technical characteristics of SDS desulfurization process


The SDS desulfurization process has good regulation characteristics. The operation and shutdown of the desulfurization unit will not affect the continuous operation of the coke oven. The load range of the desulfurization system is coordinated with the load range of the coke oven to ensure reliable and stable continuous operation of the desulfurization system. The technical characteristics of this process are as follows:


(1) The system is simple, easy to operate and maintain;

(2) Less one-time investment and small footprint;

(3) Low operating cost;

(4) Fully dry system, no water required;

(5) High desulfurization efficiency;

(6) Reasonable desulfurization agent uniform distribution device;

(7) It is highly flexible and can be adjusted at any time according to the requirements of emission indicators;

(8) It has a good removal effect on acidic substances;

(9) Strong adaptability to coke oven working conditions;

(10) The amount of by-products is small, and the purity of sodium sulfate is high, which is convenient for recycling;

(11) The system is equipped with a quick switching device for emergency channels, and once a failure occurs, it will not affect the normal production of the coke oven.

3.2 Characteristics of medium and low temperature SCR denitrification process


After the coke oven flue gas is desulfurized, a medium-low temperature denitrification catalyst is used for denitrification. The catalyst has a wide catalytic reaction temperature window, low SO2 conversion rate and NH3 escape rate, good sulfur resistance, high removal efficiency, large specific surface area, and structural strength. High, long life and other characteristics.


After the denitrification system has been running for a certain period of time, in order to keep the catalyst activity stable (to prevent the deposition of viscous ammonium bisulfate on the surface of the catalyst), the catalyst is regenerated by an in-situ regeneration thermal analysis system. When the life cycle of the catalyst expires, the SCR medium and low temperature denitrification catalyst can be returned to the factory for regeneration, which effectively solves the problem of hazardous waste treatment of the catalyst and reduces the cost of replacing the catalyst in the later stage.


4. Composition of desulfurization and denitrification process system


The coke oven flue gas desulfurization and denitrification system consists of the following parts:


(1) SDS desulfurizer dosing and uniform distribution device (key equipment should be considered for backup);

(2) Dust removal equipment and auxiliary equipment;

(3) Denitrification reactor system and auxiliary equipment;

(4) Public auxiliary equipment for desulfurization and denitrification system, including nitrogen supply system, circulating water supply, etc.;

(5) Instrumentation, communication, power supply and distribution, online monitoring, fire protection and control systems, etc.