The high‑temperature gas dust removal stainless steel filter cartridge is a metal filter element made of stainless steel matrix through a high‑temperature vacuum sintering process. It is specifically designed for dust removal and purification of hot, high‑pressure, and corrosive gases. Thanks to its excellent high‑temperature resistance, outstanding mechanical strength, and superior corrosion resistance, this filter cartridge plays an indispensable role in industrial fields such as metallurgy, chemical engineering, waste incineration, and coal‑fired power generation.
Compared with traditional chemical fibre filter bags (which generally withstand temperatures below 260 °C), stainless steel filter cartridges can operate stably for long periods at 400 °C to 750 °C, or even higher – some special products can tolerate up to 1100 °C. This remarkable temperature resistance allows direct treatment of high‑temperature flue gas without additional cooling equipment, thereby reducing energy consumption and footprint while avoiding condensation and corrosion that may result from inadequate cooling.
Stainless steel filter cartridges are made of high‑quality materials such as 304, 316L stainless steel or Fe‑Cr‑Al fibre. Standard products can operate continuously over a wide temperature range from –200 °C to 650 °C. Specially designed high‑temperature series can withstand 750 °C to 1100 °C while maintaining good structural stability in oxidizing atmospheres. The cartridges also feature excellent thermal shock resistance, being able to endure rapid temperature changes without structural damage – suitable for intermittent operation.
By using multi‑layer metal fibre felt or sintered metal powder, the filter cartridge forms a uniform, interconnected three‑dimensional porous structure, enabling high‑precision gas‑solid separation. The filtration accuracy range of standard products is 0.5 μm to 200 μm. For multi‑layer gradient filter structures, the removal efficiency for PM2.5 can reach 99.97%, and the absolute filtration accuracy under gas‑solid separation can be as low as 0.3 μm. The dust emission concentration after purification can be controlled below 5 mg/Nm³, fully meeting ultra‑low emission requirements.
The stainless steel filter cartridges are made by vacuum sintering multiple layers of metal wire mesh or metal powder, forming a dense metal skeleton structure with extremely high mechanical strength and pressure resistance. They can withstand differential pressures from 0.1 MPa to 30 MPa, and their wear resistance greatly exceeds that of chemical fibre filter bags. Regarding corrosion resistance, 316L stainless steel can tolerate nitric acid up to 40% concentration and sulphuric acid up to 80%, making it suitable for various acid/alkali corrosive media and sulphur‑containing gases. It performs particularly well in highly corrosive environments such as chemical reactors and roasting furnaces.
Stainless steel filter cartridges offer good regenerability. A 0.5 MPa compressed air back‑pulse can recover more than 90% of the permeability. For chemical cleaning, soaking in 5% nitric acid solution for two hours, combined with ultrasonic vibration, effectively removes deep‑seated contaminants. With proper maintenance, the filter cartridge can last 3 to 5 years, significantly extending the replacement interval compared to traditional filter bags and substantially reducing overall operating and maintenance costs.
Stainless steel filter cartridges maintain a stable porosity of 28% to 50%, providing good air permeability, filter medium resistance below 50 Pa, low energy consumption, and high throughput. The natural decrease in gas density at high temperatures further reduces the pressure drop, lowering system operating energy consumption.
Based on the main filter medium, high‑temperature gas dust removal stainless steel filter cartridges are mainly classified into three types:
Sintered metal mesh filter cartridge: made of five layers of stainless steel wire mesh (protection layer, control layer, dispersion layer, and two support layers) stacked and vacuum sintered at about 1200 °C to form an integrated metal skeleton. The multi‑layer structure provides a graded pore design, combining high‑precision interception with high dirt‑holding capacity, suitable for industrial applications with strict requirements on filtration stability and service life.
Sintered stainless steel fibre felt filter cartridge: produced by air‑laying uniform stainless steel fibres and then vacuum sintering. It can be designed as a multi‑layer gradient structure (pore size gradually decreasing from coarse to fine), featuring high porosity, high dirt‑holding capacity, and excellent filtration precision. This type is often pleated to increase filtration area.
Sintered stainless steel powder filter cartridge: made from 304, 316L or other stainless steel metal powders, pressed in a mould and then vacuum sintered at high temperature to form a porous structure with uniform interconnected pores. This process requires no binders; the pore size distribution is controlled by the metal powder particle size. It offers high material utilisation and can produce various shapes (tubes, rods, plates, etc.) in batches.
Metallurgy and steel industry: widely used for high‑temperature dust removal from blast furnace gas and converter flue gas. It can treat dust concentrations up to 500 g/m³ with a dust removal efficiency >99.9%, reducing the cleaned gas dust concentration below 10 mg/Nm³.
Chemical and petrochemical industry: suitable for high‑temperature process gas purification in catalytic cracking units, catalyst recovery, and polymer melt filtration. Operating temperature can reach 500 °C, with resistance to highly corrosive media such as sulphides and chlorides.
Waste incineration and energy/environmental protection: widely used in waste incinerator tail gas treatment and coal‑fired boiler flue gas dedusting, meeting ultra‑low emission requirements (discharge concentration ≤5 mg/Nm³). The high outlet gas temperature facilitates waste heat recovery.
Cement and glass industry: used for high‑temperature kiln exhaust gas treatment, able to withstand high dust concentration impacts and maintain stable filtration performance under long‑term continuous high‑temperature operation.
Proper selection and correct use are critical to maximising the service life and filtration performance of stainless steel filter cartridges. First, choose the appropriate material according to the chemical nature of the medium, operating temperature, pressure, and impurity characteristics – 304 stainless steel for general corrosive environments, 316L or higher grades for strong corrosion and chlorine‑containing environments. During installation, the cartridge must be kept vertical, ensuring the sealing ring is correctly seated; no missing or misaligned parts are allowed.
For daily operation, it is recommended to back‑flush the cartridge once per shift (every 8 hours) before shutdown. Back‑flush pressure should be applied gradually, never instantaneously. Routine cleaning can be done by back‑flushing (pressure ≤5 MPa) combined with soaking in 0.1 N NaOH or citric acid solution. For severe clogging, ultrasonic cleaning or chemical cleaning (acid or alkali wash) should be used. When the differential pressure exceeds 0.3 MPa or the filtration efficiency drops below 50%, cleaning or replacement is required. Cartridges that fail to recover 30% of their initial filtration efficiency after five cleaning cycles should be replaced.
High‑temperature gas dust removal stainless steel filter cartridges have become an indispensable core filtration component in the field of high‑temperature flue gas purification, thanks to their excellent high‑temperature resistance, high‑precision filtration, outstanding corrosion resistance, and long service life. From steelmaking and chemical catalysis to waste incineration and coal‑fired power generation, this product provides solid technical support for ultra‑low emissions and green production across various industries. With continuous advances in materials science and manufacturing processes, stainless steel filter cartridges will surely demonstrate even greater value in broader applications, driving industrial dust removal technology to higher levels.
