Rotary Furnace VS Multiple Hearth Furnace VS Slepp Furnace | Activated Carbon Furnace Buying Comparison Guide

Three types of activation furnaces dominate the global activated carbon production & regeneration market: continuous rotary kiln, multiple hearth furnace (rake furnace) and traditional Slepp furnace. Each equipment has unique structural characteristics, applicable production scales and cost attributes. No absolute superior model, you only need to match equipment according to your daily output, raw material type, budget and production flexibility demands.

Dimension-by-Dimension Comprehensive Comparison

Production Continuity & Throughput Capacity

Rotary Activation Furnace: Fully continuous running, daily output 0.5–25 tons, expandable for large-scale mass production; uniform material tumbling heating, no dead heating zone inside kiln, highest single-line productivity;

Multiple Hearth Furnace: Semi-continuous operation, medium daily throughput 1–8 tons, stable output for medium-sized carbon plants;

Slepp Furnace: Intermittent periodic production, small daily output 0.3–3 tons, only fit small-batch customized carbon production.

Raw Material Adaptability

Rotary furnace: Compatible with granular carbon, powdery carbon, coconut shell carbon, coal-based carbon, wood carbon, irregular carbon particles, widest material adaptability;

Multiple hearth furnace: Ideal for coal-based granular activated carbon, widely used in gold mine carbon regeneration industry;

Slepp furnace: Mainly for coconut shell & wood biomass carbon, poor adaptability to powdery materials.

Energy Consumption & Operating Cost

Rotary furnace: Equipped with tail gas waste heat recovery, lowest unit energy consumption, long-term operation cost-saving;

Multiple hearth furnace: Medium energy consumption, stable operation with moderate daily power/gas cost;

Slepp furnace: No effective heat recycling, highest energy consumption per ton finished carbon.

Initial Investment & Maintenance Difficulty

Slepp furnace: Lowest upfront procurement price, simple structure, cheap vulnerable parts, friendly for small startups with limited budget;

Multiple hearth furnace: Medium investment cost, regular rake teeth replacement required, moderate maintenance workload;

Rotary furnace: Higher one-time investment, fewer wearing components, ultra-low failure rate, long service life for long-run large factories.

Final Selection Suggestions

1.Choose Rotary Activation Furnace: Large daily output, diversified carbon types, long-term continuous production, pursue low comprehensive operation cost;

2.Choose Multiple Hearth Furnace: Gold mine carbon elution & regeneration, fixed coal-based granular carbon processing, medium-scale environmental engineering companies;

3.Choose Slepp Furnace: Small workshop biomass carbon making, small batch customized activated carbon production, tight initial budget.