-
-
Product
-
-
Condensate Control in Flue Gas Treatment for Gas Boilers Using Horizontal Mist Eliminators
Release time:
Jul 29,2025
[Summary]In gas boiler flue gas treatment systems, the control of condensate in horizontal mist eliminators directly affects the system’s operational stability and compliance with emission standards. With the continuous tightening of the "Emission Standards for Air Pollutants from Boilers" (GB 13271-2014), this technical stage has become a critical node in the upgrading and retrofitting of environmental protection facilities.
In gas boiler flue gas treatment systems, the control of condensate in horizontal mist eliminators directly affects the system’s operational stability and compliance rate with emission standards. With the continuous tightening of the “Emission Standards for Air Pollutants from Boilers” (GB 13271-2014), this technical stage has become a critical node in the upgrading and retrofitting of environmental protection facilities.
Flue gas from gas-fired boilers typically contains large amounts of saturated water vapor. When the flue gas temperature drops below the dew point, condensation droplets form. The horizontal mist eliminator, with its multi-layer corrugated plate structure, effectively captures droplets with diameters greater than 15 μm through inertial impaction. Actual operational data show that a horizontal mist eliminator made of 316L stainless steel can achieve a condensate removal efficiency meeting the design specifications under operating conditions of 130°C, while maintaining system pressure drop within 800 Pa.
In terms of condensate control, three technical parameters require particular attention: First is the setting of plate spacing, which is typically maintained within the range of 20–30 mm to accommodate variations in air flow under different load conditions. Second is the configuration of the flushing system; adopting an intermittent spray pattern can effectively prevent scaling on the plates. Most importantly, the design of the condensate drainage slope is critical—recommended at a 5° incline—to ensure smooth condensate drainage. Operating records from a certain combined heat and power project show that a horizontally arranged mist eliminator with an optimized angle can reduce the condensate retention time by 40%, significantly lowering the risk of secondary entrainment.
Material selection also significantly affects the effectiveness of condensate treatment. For flue gas environments containing sulfur, it is recommended to use 2205 duplex stainless steel or glass-reinforced plastic; the materials’ pitting resistance equivalent (PREN) value should be greater than 35. In projects located in coastal areas, applying an additional surface coating of polytetrafluoroethylene has been proven to effectively resist chloride-ion corrosion and extend the equipment maintenance cycle to over three years.
The development of intelligent control systems has provided new insights into condensate management. By installing differential pressure transmitters and humidity sensors, it’s possible to establish a model of the demister’s operational status. When the pressure drop exceeds the preset threshold, an automatic flushing procedure is triggered. This predictive maintenance approach ensures that the horizontal demister consistently operates within its optimal performance range. According to a comparative report by an environmental monitoring agency, systems employing intelligent control can keep the fluctuation幅度 of condensate discharge indicators within ±5%.
As carbon reduction requirements become increasingly stringent, the waste heat recovery function of horizontal mist eliminators has attracted growing attention. Some retrofit projects have attempted to install heat-exchange devices in the downstream section of mist eliminators, using the waste heat from the collected condensate to preheat make-up water. This design can improve boiler thermal efficiency by approximately 1.2 percentage points. It is important to note that when implementing such retrofits, it is essential to re-evaluate and rebalance the system’s pressure drop to avoid adversely affecting the operational conditions of the original dust removal equipment.
Keywords:
Horizontal demister
Previous page
Recommended News
Address: District B, Packaging and Equipment Manufacturing Park, Dongguang Economic Development Zone, Cangzhou City, Hebei Province
Service Hotline:0086-317-7666022
Email:zrhb7666022@163.com
Official Website