Types of activated carbon for water treatment of fruit shells - Types of commonly used activated furnaces for fruit shell activated carbon: (1) Schlieper furnace: also known as saddle furnace, because the refractory bricks in its activation zone are saddle shaped. It was originally a French patent and was introduced to China by the former Soviet Union in the 1950s. After a series of improvements, it has become the main furnace type for producing granular activated carbon in China.

Activated gas: water vapor.

Main advantages: continuous production, large output, high quality, high superheated steam temperature, stability, no need for external heating.

Main issues: high requirements for raw materials, high cost, high technical requirements, and high maintenance costs.

(2) Stewing furnace:

Activated gas: High temperature flue gas produced by coal combustion.

Main advantages: simple investment and low cost.

Main problems: high fuel consumption, uneven activation, high labor intensity, and large dust.

(3) Earth rake furnace:

Activated gas: water vapor (air)

Main advantage: The simplest furnace type.

Main issues: low yield, low quality, primitive workshop style, and environmental pollution.

(4) Multi tube furnace:

Activated gas: water vapor

Main advantages: no need for fuel, stability, easy control, and high output.

Main issues: uneven activation, low carbon quality, low superheated steam temperature, easy damage to refractory pipes, and significant investment.

(5) Rotary furnace:

Activated gases: flue gas, water vapor

Main advantages: continuous operation, uniform activation, suitable for producing gas-phase activated carbon.

Main issues: large equipment, poor thermal efficiency, fuel consumption, and low quality of finished products.

(6) Boiling furnace

Activated gases: air, water vapor.

Main advantages: good gas-solid contact, uniform activation, and small mechanical footprint.

Main issues: intermittent production, easy slagging affecting normal operation, and fuel consumption.