Frequently Asked Questions

Biogreen is suitable for torrefaction, carbonisation, pyrolysis and high temperature pyrolysis, as well as calcination processes. 

Fully controlled and air-free atmosphere of reaction makes our system capable to valorise all kind of biomass and waste by using wide range of temperatures, from 200°C up to beyond 800°C. Thanks to that, range of Biogreen applications covers variety of process for solid fuel, biocoal and biochar production as well as waste to energy conversion.

The external energy that powers Biogreen is electricity. Biogreen technology is based on an electrical heating screw conveyor (Spirajoule) which directly transfers the heat to the product. The product temperature is precisely controlled based on the heating screw temperature setting while the residence time (dwell time) is regulated by screw rotation speed setting. This unique construction of pyrolyser guarantees process flexibility and constant quality in all forms of treatment applied in Biogreen.

Biogreen was first developed in 2003. The first unit, a pyrolysis process for converting wood (sawdust) into biooil and biochar, operates successfully until today. 

Until today, we have provided over 45 Biogreen units operating on different feedstocks worldwide.

The Biogreen process can be tested in Europe or in USA and you can find more details about the typical testing services here on our websites. Please contact our representative to find out the possible scope and date of testing.

A wide range of Biogreen units is available. The most common capacities of machine models is explained on our websites.

The actual mass flow of product treated in Biogreen will depend on two factors: its bulk density and applied residence time, which is the time spent by product inside the Biogreen reactor. Depending on the treatment purpose, residence time can be setup within the range between 5 up to over 40 minutes.

Product ratio depends on characteristics of treated material and operating conditions.

Lower process temperatures (250 – 400°C) favour the highest production of solid product (60-85%) making the process suitable for biomass to charcoal and bio-coal conversion. Moderate temperatures (450 – 600°C) increase the production of oil (up to 40%). High temperature treatment (650 – 800°C) direct the process to obtain maximum syngas amounts (up to 95%) for highest potential for energy valorisation (heat and electricity production). Regulation of operating conditions (temperature and residence time) makes Biogreen a precise tool for waste and biomass conversion, suitable to navigate the process and obtain most expected results.

Efficiency is given by the ratio: output energy / input energy to the system. Global efficiency of Biogreen is up to 80 – 95%.

Biogreen is a brand of ETIA, an innovative and worldwide patented continuous thermal treatment system, which can be used as carbonizer, pyrolyzer or gasifier. It can convert any kind of waste and by-products, such as biomass (forest or crop residues), plastics (RDF, SRF from municipal or industrial waste), rubber (waste tires) sewage or industrial sludge. Treatment performed in Biogreen allows to transform these resources into a new products and energy.

Limitations are:

• Rheological (flow characteristics) properties of the feedstock. The product must be a free flowing, bulk material transportable by a screw conveyor without a sticking problem.
• Inlet moisture of material should be as low as possible (recommended < 10%)
• Particle size into the Biogreen should be less than 30 mm

This depends on the model of equipment. Standard 1 tonne per hour unit of the Biogreen footprint can be as low as 15 m X 5m X H 4 m.

Standard configuration of Biogreen includes:

• Hopper for feedstock storage (to ensure approx. 20 min of production)
• Feeding and extraction systems before and after the pyrolyzer to ensure air restricted atmosphere of the pyrolyzer
• Spirajoule pyrolyzer with electrical heating screw technology
• Cooler for solid phase with a double jacketed auger with circulation of chilled water and water spray system
• Transformer, electrical cabinet and control panel with PLC
• Container or platforms for operator’s access
• System for syngas management, typically conversion into hot water or steam

Standard configuration of Biogreen does not include (following elements can be proposed as option):

• Dryer for the feedstock
• Grinder for the feedstock
• Specific gas cooling and cleaning system
• Syngas engine (applied to valorise syngas to electricity)
• Final gas treatment (sized and design accordingly to local compliances and regulations)

Biogreen’s experience covers : wood residue (chips and sawdust), crop residue (straw), animal manure (chicken and pig), sewage sludge, industrial organic sludge, plastic foil and used tires.