Compared with activated carbon filter, what are the advantages of carbon fiber filter in industrial wastewater purification?
In the field of industrial wastewater purification, compared with the traditional activated carbon filter, carbon fiber filter shows many remarkable advantages by virtue of its unique structure and performance, especially in certain working conditions, which can meet the requirements of efficient and stable treatment, as follows:
First, higher adsorption efficiency and capacity
The specific surface area and pore structure are better: carbon fiber has a more developed micropore and mesopore structure, and the pore size distribution is more uniform, and the specific surface area is usually higher than that of ordinary activated carbon (up to 1500-3000㎡/g). This structure makes the adsorption rate of small molecular organics (such as dyes, phenols and pesticide residues) and some heavy metal ions (such as lead, cadmium and chromium) in wastewater faster, and the adsorption capacity per unit volume is higher.
Strong anti-adsorption competitiveness: in complex industrial wastewater (mixed system containing multiple pollutants), carbon fiber has more outstanding selective adsorption capacity for target pollutants, and is not easily disturbed by other impurities, especially for low-concentration pollutants.
Second, better pollution resistance and blockage resistance
Advantages of fibrous structure: carbon fiber filter elements are mostly fiber bundles or felt-like structures, with good pore connectivity and low water flow resistance, and are not easily blocked by the accumulation of suspended solids (SS), colloids and other impurities. In contrast, the pores of granular activated carbon filter are easily filled with fine particles, which leads to a faster rise in pressure difference.
Stronger chemical corrosion resistance: carbon fiber itself has high chemical stability, and its acid resistance and alkali resistance are better than most activated carbons (especially coal-based activated carbons). When treating industrial wastewater with high pH (such as printing and dyeing wastewater) or low pH (such as electroplating wastewater), it has a longer service life and slower performance decay.
Third, longer service life and lower replacement frequency
Better pollution tolerance: because of the "deep filtration" characteristics of fiber structure, pollutants can be adsorbed or trapped inside the filter element rather than on the surface, so it takes longer to reach saturation or blockage. Under the same working conditions, the replacement cycle of carbon fiber filter is usually 30%-50% longer than that of activated carbon filter (for example, from 1 month to 1.5-2 months).
Anti-biological pollution: the surface smoothness of carbon fiber is higher than that of activated carbon, and it is not easy to breed bacteria or microorganisms (especially when treating industrial wastewater with high nitrogen and phosphorus), thus reducing the performance degradation caused by biofilm adhesion.
Fourth, better regeneration performance
High regeneration efficiency: the saturated carbon fiber filter element can recover its adsorption performance by thermal regeneration (such as heating under nitrogen protection) and chemical elution (such as acid/alkali solution), and the structure is not easy to be damaged during regeneration, so it can be reused more times (usually 3-5 times more than activated carbon).
Low energy consumption for regeneration: carbon fiber has good thermal stability, and the temperature required for thermal regeneration (usually 300-500℃) is lower than that of some activated carbon (for example, coconut shell activated carbon needs more than 600℃), thus reducing energy consumption in the regeneration process.
Fifth, more suitable for high-demand working conditions
Treatment of high-viscosity or oily wastewater: The hydrophobicity of carbon fiber surface (which can be adjusted by modification) makes it difficult to fail when treating oily wastewater or high-viscosity organic wastewater, while activated carbon is easily wrapped in oil, which leads to a sudden drop in adsorption capacity.
Adaptability of high-temperature wastewater: The high-temperature resistance of carbon fiber is better than that of most activated carbon (the long-term use temperature can reach 150-200℃), and the performance stability is more prominent when treating high-temperature industrial wastewater (such as the drainage of chemical reaction kettle).
summary
In the purification of industrial wastewater, carbon fiber filter element has the core advantages of high adsorption efficiency, pollution resistance, long life and easy regeneration, and is especially suitable for treating industrial wastewater with complex pollutant composition, large concentration fluctuation or harsh conditions such as high temperature and high acid and alkali. However, its initial procurement cost is usually higher than that of activated carbon filter, so in practical application, it is necessary to combine the wastewater nature, treatment cost and long-term operation economy. For high-demand and difficult purification scenes, the performance advantage of carbon fiber filter can often cover its cost difference.
