Improving the efficiency of flue gas desulfurization and denitrification is the key goal of current industrial enterprises to achieve ultra-low emissions, meet environmental protection regulations, and promote green production. To achieve high-efficiency flue gas treatment, it is necessary to make comprehensive efforts in multiple aspects such as technology selection, system optimization, operation management and supporting measures. The following are several major strategies to improve efficiency: 1. Choose an efficient and adaptable technical route The primary determinant of desulfurization and denitrification efficiency is the process technology used. In terms of desulfurization, the wet limestone-gypsum method is widely used in large coal-fired power plants due to its full reaction and high desulfurization rate (up to more than 95%); for small and medium-sized equipment or occasions with high requirements for water resource utilization, semi-dry or dry desulfurization can be selected. Although the efficiency is slightly lower, it has a compact structure and is easy to operate. In terms of denitrification, **SCR (selective catalytic reduction)** has an efficiency of up to 80% to 95%, which is the most commonly used high-efficiency denitrification technology and is suitable for occasions with strict requirements for NOₓ emission control; **SNCR (selective non-catalytic reduction)** is suitable for projects with limited space or high cost control requirements.
2. Accurately control reaction conditions
Whether it is desulfurization or denitrification, it depends on specific temperature, gas flow rate and reactant concentration to ensure the best reaction efficiency. For example, the optimal reaction temperature of the SCR denitrification system is generally 300℃～400℃. Too high or too low will lead to a decrease in catalyst activity; in the desulfurization reaction, the slurry pH value and limestone particle size have a significant impact on the reaction efficiency. Real-time monitoring and adjustment of flue gas parameters through an automated control system (such as DCS or PLC) can stabilize the system operation, prevent excessive ammonia injection or limestone waste, and improve resource utilization.
3. Optimize the use of catalysts and absorbents
Catalysts and absorbents are the core materials for improving treatment efficiency. For denitrification systems, highly active, sulfur-resistant, and anti-poisoning catalysts should be selected, and the catalyst activity and pressure drop should be monitored regularly, and regenerated or replaced when necessary. For desulfurization systems, the use of highly reactive limestone or lime powder to improve its fineness, purity and dispersibility will help improve absorption efficiency. In addition, regular cleaning of nozzles, pipes and towers to avoid scaling and blockage can also help improve reaction effects.
4. Strengthen equipment maintenance and system coordination
The problems of dust accumulation, corrosion, scaling, etc. in equipment operation will reduce the contact efficiency between flue gas and reactants, thereby affecting the removal rate. Therefore, a sound maintenance system should be established to regularly inspect and maintain key components such as desulfurization tower nozzles, catalyst layers, slurry circulation pumps, ammonia injection systems, etc. to ensure that the system operates in the best condition. At the same time, the coordination between desulfurization and denitrification and dust removal, heat exchange, wastewater treatment and other systems should be strengthened to ensure the overall process synergy and efficiency.
5. Use intelligent management methods
The introduction of intelligent control systems, industrial big data and online monitoring technologies can realize real-time monitoring and intelligent optimization of desulfurization and denitrification systems. For example, emission data can be obtained through the flue gas continuous emission monitoring system (CEMS), combined with the model optimization control algorithm, and absorbent or reductant can be added on demand, thereby improving efficiency and reducing operating costs while ensuring that emissions meet standards.
In summary, improving the efficiency of flue gas desulfurization and denitrification does not rely on a single measure, but is a system engineering covering technology selection, parameter control, equipment management and intelligent optimization. Enterprises should make differentiated configurations based on their own working conditions and formulate scientific operation and maintenance plans to achieve a win-win situation of pollution control and economic benefits.