Recovery Purpose

Treated wastewater after secondary or membrane treatment contains residual organic compounds. Discharge limits or reuse applications require further polishing. Activated carbon adsorption removes dissolved organics achieving stringent quality requirements.

Vessel Configuration

Vertical pressure vessel with treated water inlet distributor, activated carbon bed typically 36-60 inches depth, support gravel preventing carbon loss, underdrain system, polished water outlet. Empty bed contact time 10-20 minutes for organics removal.

Carbon Media

Granular activated carbon from coal or coconut shell. Particle size 8x30 or 12x40 mesh. High iodine and molasses numbers indicate adsorption capacity. Carbon life 1-3 years before exhaustion depending on organic loading.

Operating Pressure

Typical 50-100 psig service. Clean bed pressure drop 8-15 psi. As carbon loads with organics, pressure drop increases modestly. Carbon exhaustion indicated by organic breakthrough not pressure.

Organic Removal

Adsorbs dissolved organics, humic substances, pharmaceuticals, personal care products, endocrine disruptors, and trace industrial compounds. Reduces total organic carbon (TOC) and chemical oxygen demand (COD). Color removal improving water appearance.

Material Selection

Carbon steel with epoxy lining or stainless steel for corrosion resistance. FRP construction for treated wastewater. Internal distribution systems corrosion-resistant. External coating for atmospheric protection.

Backwash Requirements

Periodic backwash removes particulates and redistributes bed. Flow rate 8-10 gpm per square foot expanding bed 10-15%. Less frequent than sand filters as carbon primarily adsorbs. Backwash extends run length between regenerations.

Applications

Municipal wastewater reuse for irrigation or industrial use, industrial effluent polishing before discharge, tertiary treatment for nutrient removal systems, membrane concentrate treatment, and any water recovery requiring organics removal.

Breakthrough Monitoring

TOC or UV254 analyzers detect carbon exhaustion. Breakthrough signals regeneration or replacement requirement. Monitoring prevents poor quality water release.

Regeneration Options

Spent carbon thermally reactivated off-site at 800-900C restoring 85-95% capacity. More economical than replacement for large installations. Small systems replace carbon disposing spent media.

Water Reuse Quality

Polished water suitable for industrial cooling, irrigation, groundwater recharge, or indirect potable reuse depending on regulatory requirements. Carbon provides final barrier removing micropollutants.

Capacity Sizing

Volume based on water recovery rate and required contact time. Typical design provides 12-24 months operation before regeneration. Balance between carbon inventory and replacement frequency.

Performance Benefits

Enables water reuse through organics removal. Meets stringent discharge requirements for sensitive receiving waters. Simple proven adsorption technology. Predictable performance with proper monitoring.

Construction Standards

Pressure vessels per ASME Section VIII. Materials for treated wastewater service. Design accommodates carbon weight when saturated. Complete documentation with contact time calculations and media specifications.

ERGIL activated carbon water recovery tanks provide tertiary organics removal enabling wastewater reuse and stringent discharge compliance in municipal and industrial applications.