How long can activated carbon be used?

Factors affecting lifespan

Water type Expected lifespan Key limiting parameter

Municipal tap water 6-12 months Total treatment volume ≤ 300m³/ton carbon

High organic matter water source 3-6 months TOC concentration > 4 mg/L

High chlorine water body 2-4 months Residual chlorine > 1.5 mg/L

Failed core mechanism

■ Adsorption saturation

Pore volume filling rate > 95% (BET specific surface area decreases to 60% of the initial value)

Iodine adsorption value < 600 mg/g (失效 standard of GB/T 12496-2015)

■ Channel blockage

Pressure difference △P > 0.08 MPa (initial value 0.02-0.03 MPa)

Turbidity load > 10 NTU accelerates pore clogging

Change the criterion

Performance degradation indicator

Residual chlorine penetration: outlet concentration > 0.1 mg/L (GB 5749 limit value 0.05 mg/L)

Organic matter leakage: UV254 absorbance increase > 25%

Operational abnormality characteristics

Product water flow rate decrease ≥ 30% (under constant feed water pressure of 0.2 MPa)

Olfactory threshold TON ≥ 4 (earthiness/moldy odor detected)

Cycle management recommendations

Routine monitoring: Test export TOC/residual chlorine monthly

Mandatory replacement: Continuous use ≥12 months (even if performance has not significantly declined)

Maintenance misconception warning

Visual judgment is invalid: No change in the appearance of activated carbon (requires instrumental testing)

Washing and regeneration are ineffective: Backwashing only removes suspended solids and cannot restore adsorption capacity

Risk of extended service life: Excessive use leads to microbial growth (total colony count > 100 CFU/mL)

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