The pyrolysis or pyrolytic decomposition (from ancient Greek: ‘fire’ and ‘solution’) is a thermochemical decomposition of organic waste. With high temperatures (200-900 °C) and a controlled addition of oxygen, large molecules are broken into smaller ones. The word pyrolysis is used in the narrow sense for processes in which, in addition to the mineral constituents of the feedstock, solid carbon remains (plant charcoal).
Biomass gasification is a process in which biomass is converted into a fuel gas. The biomass is first treated in a pyrolytic reactor. The resulting pyrolysis gas is a mixture of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), methane (CH4) and a number of trace gases. Gases, liquids and solids are generally formed. The quantities and the composition of the pyrolysis gas depend not only on the feedstock, but also on the pyrolysis temperature, the added excipients, the pressure ratios and the treatment time.
Gasification versus combustion:
The gasification has a higher added value, than combustion, since the gas can be used, as a fuel in engines for the production of energy or in special furnaces for the production of heat-for example in kilns.
In the case of gasification, one decreases substantially the nitrogen oxide emissions from fuel nitrogen because, in the production of gas, under oxygen deficiency, only a small part of the fuel nitrogen is converted to nitrogen oxides.
In the case of gasification, it is possible to produce charcoal as a by product for direct energy use since it can be sold as activated carbon for the grills. In this manner the charcoal can help to improve the economy of the plant.
During the combustion of the wood gas, an almost complete combustion with low emissions of unburned hydrocarbons and carbon monoxide can be achieved by a suitable mixing of the combustible wood gases with the combustion air and thus combustion with a small air excess and high temperature can be achieved.
Since the gasification process is carried out under oxygen deficiency, reducing conditions prevail in the reduction zone of the reactor, where the gasification takes place. Therefore, the resulting gas has a lower proportion of metal oxides and the proportion in metals bounded in form compounds is higher than in the case of combustion. The results from various investigations indicate that the heavy metals are incorporated into the coal in an inert form during high-temperature gasification and pyrolysis processes.
What are the advantages of a pyrolysis plant?
Our reactor produces up to a ton of high-quality plant charcoal per day. As a by-product, storable bio-oil and immediately available energy in the form of biogas are produced. The plant uses only organic waste that is produced every day: wood residues, compost, foliage, lawn cutting.
Everything that is organic can be converted into energy without harming the environment.
A clean waste treatment, then?
Yes, even better: when the plant charcoal is distributed on the fields, one achieves a CO2 reduction, a necessary technology in times of climate warming. The plant produces not only plant charcoal, but also with the produced biogas one can generate sustainable heat or electricity. In this way the pyrolysis machine is a small climate friendly power station.
We realized the enormous potential of this technology and thought that the benefits from the pyrolysis technology should be made widely known. So we decided to market our pyrolysis plant.
Why is pyrolysis technology a solution to the CO2 problem?
In the pyrolysis process, the CO2 is bound into the plant charcoal. In addition, the distribution of the plant charcoal over agricultural fields, result in an active fixation of the CO2 in the soil. The CO2 thus stored remains stable in the soil in a water-insoluble form.