SCR: Selective Catalytic Reduction (SCR) refers to the use of a reducing agent (such as NH
3, liquid ammonia, urea) to "selectively" react with NOx in flue gas under the action of a catalyst to produce non-toxic and non-polluting N
2 and H
2O.
Principle of SCR denitrification system:
The urea aqueous solution meets the high-temperature flue gas in the mixing tube and decomposes into ammonia (NH3) and water (H2O). After being fully mixed with the flue gas, it enters the SCR reactor. Under the action of the catalyst, NH3 and NOx are catalytically reduced to harmless nitrogen (N2) and water (H2O).
Features and Advantages
Basic composition
SCR reactor module, metering injection module, NOx/O,/NH measurement module, pulse soot blowing control module, reductant automatic filling module, Internet of Things module.
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SCR reactor module
It consists of a reactor shell and a denitration catalyst. The SCR denitration catalyst that meets customer needs can be selected according to on-site working conditions to ensure denitration efficiency and stability.
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Metering injection module
The high-precision gear metering injection pump can achieve multi-level reducing agent injection control, such as 0-7.5L/h, 0-60L/h, and 0-120L/h. The metering injection module can be expanded to achieve precise metering injection of various flow rates. Semi-closed-loop control can be achieved by accurately measuring the reducing agent injection amount by measuring flue gas flow temperature, NOx concentration, pressure, and target denitrification rate. The PID controller can also automatically adjust the reducing agent injection amount by setting the target NOx concentration. The small dual-fluid spray gun has a small atomized particle size, a SMD value better than 30μm, and precise metering.
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N0x/0,/NH, measurement module
Used in conjunction with the metering injection module, the core part adopts measuring components imported from Germany. The NOx measurement error is ≤±5%, and the maximum range is 1500ppm. The NH: measurement error is ≤±5%, and the maximum range is 50ppm. It can replace CEMS for continuous measurement of NOx/O./NH; at the inlet and outlet of the SCR reactor.
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Pulse sootblowing control module
It can be integrated into the metering injection module and connected to the soot blowing solenoid valve. The soot blowing frequency and time interval can be set to effectively avoid catalyst blockage.
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Reductant automatic filling module
This module consists of a centrifugal pump, filter, flow controller, heater (optional), etc. It is connected between the reductant storage tank and the metering module control module and operates independently. When the liquid level in the buffer tank of the metering injection module is insufficient, the filling program is automatically started.
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IoT module
Collect various data in the system and transmit them to the server. Users can view the equipment operation status in real time through the client.
Fully automatic intelligent system
This fully automatic intelligent system precisely measures the amount of reducing agent injected by measuring flue gas flow, temperature, NOx concentration, pressure, and target denitrification rate. Injection automatically stops if the urea level or compressed air pressure is low. In the event of a power outage, compressed air outage, or compressed air shutoff, the system automatically purges the spray gun to prevent clogging and resumes operation once normal operation is restored. The system includes a self-diagnostic function for real-time monitoring of operating status. Users only need to monitor the urea drum level and the adequacy of compressed air; all other parameters are fully automated and require no human intervention. The large color touchscreen displays all parameters at a glance.
Anti-clogging function for spray gun
After many rounds of improvements, our company has successfully developed a spray gun anti-clogging device. In the event of an unexpected power outage, compressed air outage, or low compressed air pressure, it automatically stops the urea pump from spraying and performs a purge, preventing the spray gun from clogging. We are currently the only company in the industry with this technology.
High-temperature flue gas flow direct measurement technology
High-temperature flue gas flow direct measurement technology does not require the collection of equipment parameters or manual parameter input. It is resistant to high temperatures and dirt and can directly measure flue gas flow. It can also perform flow correction based on temperature and back pressure.
Denitrification near-zero emission technology
Through the real-time data of flue gas flow, temperature, NOx concentration, NH, concentration, pressure, etc.
According to the data collected, precise control is achieved through our self-developed metering injection pump and spray gun to achieve near-zero emissions of NOx and NH.
Professional technical team
With CFD simulation calculation and analysis capabilities, we can provide customers with professional technical services to ensure zero-risk and high-efficiency projects.
+86-13912738403
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