Pyrolysis

Pyrolysis is a form of incineration that chemically decomposes organic materials in the absence of oxygen. Pyrolysis typically occurs under pressure and at operating temperatures above 430 °C (as opposed to incineration and co-incineration which use oxygen so it oxidizes bulk quantities of waste that may be in liquid and solid phase). Several types of pyrolysis units are available, including the rotary kiln, rotary hearth furnace, or fluidized bed furnace.

Semi-solids and solid
Polluted sand
 

There are little installations available (recent technology).

Organic materials are transformed into gases, small quantities of liquid, and a solid residue containing carbon and ash. These co-products can be re-used (as energy or material).

The technology requires drying of the soil prior to treatment.
Particulate removal equipment is also required.

Depends on the type of equipment used.

Pyrolysis results in the production of solid residues (char), liquid residue (oil/ water) and gases that must be disposed of adequately.
Incinerators may release carcinogenic and toxic chemicals, including heavy metals, partially-burned organic material such as polyvinyl chloride (PVC), and other organic chemicals, including polycyclic aromatic hydrocarbons (PAHs), dioxins and furans.
The concentration of the release depends on the type of waste, of incinerator and the filter installed on the chimney.

Refer to incineration and atmospheric releases legislation.
Special authorisation may be required for such work.

Pyrolysis is still a recent technology. First tests have proven the efficiency of the system.

CAPEX: very high if no existing installation.
OPEX: to define depending on installation. 75 to 300 euros / m3 (Source: Koller)