How to Make Olive Pomace Into Biomass Pellets

As a result of agroindustrial activities in southwestern Europe, a great amount of residues are generated; among them, olive pomace stands out as one of the most abundant. One interesting alternative to increase its potential as biofuel can be its densification. However, in order to achieve high quality pellets, it is necessary to blend this material with other feedstocks.

Olive Pomace Characteristics

After the olives have been pressed and the olive oil is extracted, the olive cake is very wet. The moisture content is approximately 40-70% depending on the olive oil extraction process. The effective method of recycling this waste product is to dry it. After drying, the moisture content goes down to 8-15 %. The dried olive residue was utilized since ancient times in the Mediterranean for cooking and heating. When burned directly, the energy stored in the olive pomace is transformed and released as heat. The calorific value of olive pomace is quite high and comparable to that of coal. And its calorific value largely exceeds that of wood waste biomass. Therefore, the potential of making pellets out of olive pomace is a viable alternative. With several processes, the natural waste resource is turned into high-value energy products and a premium quality biomass fuel pellet.

Olive Pomace Distribution

Olive pomace is sourced basically from the areas with large olive tree plantation and a well-established olive oil industry. Olive is the most widely cultivated fruit crops in the world with a cultivation area of more than 10 million ha worldwide, and 95% of world’s olives are produced in the Mediterranean region. Most countries along the Mediterranean Sea produce olive oil in varying quantities. Spain, Italy, and Greece represent more than three-fourths of the total olive oil output in the world.

The largest producer, Spain, supplies about one-third of the olive oil globally. The olive oil produced in Spain is exported to nearly 100 countries. Spain has 2.5 million hectares of olive tress under cultivation, where the Andalusia region occupies the southern third of the peninsula and represents the most important region, it produces approximately 75% of the total olive oil produced in Spain.

Italy is the second largest olive oil producer, with one-fourth of the global total production. The Italian olive production covers approximately an area of 1.2 million ha, 80% of which is located in southern Italy, where Puglia represents the most important region, with about 0.37 million ha, followed by Calabria and Sicily. In the centre-north of Italy, the most important regions for olive-tree production are Tuscany, Lazio, Campania, and Abruzzo.

Greece devotes 60% of its cultivated land to olive growing. Greece holds the third place in world olive production. About 30% of Greek olive oil is produced in island Crete, 26% in Peloponissos (southern peninsula), 10% in Aegean island of Lesvos, 10% in the Ionian Islands (Adriatic Sea) and the remaining 24% is scattered around the rest of the country. With a consumption of about 20 quarts (19 litres) per person per year, Greeks are the largest consumers of olive oil per capita in the world.

How to Make Olive Pomace Into Biomass Pellets

In the complete olive pomace pellet production line, the processing procedures of drying, pelletizing, cooling, screening and packing are included.

Drying

Olive pomace has a high moisture content of 40-70%, depending on the olive oil extraction process. Then a rotary drum dryer is essential. The rotary dryer has a slight inclination, acting as a conveying device and stirrer. The goal of the drying process is to reduce the moisture of olive pomace to approximately 12%, which is suitable for pelletizing.

Pelletizing

After drying, the olive pomace can be pelletized directly without any further treatment. The ring die pellet machine is more proper for olive pomace pellet production. And the ring die compression ratio should be higher than 1:6.5. No adhesive added in this procedure.

Olive Pomace Pellet Machine

Cooling & sieving

Pomace pellets discharged from pellet mill are high in temperature and moisture content. Our counter current pellet cooler is used to remove pellet heat as well as the moisture content to ensure pellets quality and shelf-life. Simultaneously, the powder materials or unshaped pomace pellets are sieved and send to the pellet mill again.

Packing

After cooling, the packing process is necessary to protect the pomace pellet from damp and dus

Pellet Characteristics of Olive Pomace Pellet Machine

• Diameter: 6 and 12 cm/Diameter
• Low Moisture content
• Low Ash content
• High Net calorific value
• High Density
• High Durability
• Advantages of Pellets

The raw materials are sourced form recycled natural waste.

Considered carbon neutral since the plant inhale carbon dioxide when they grow and store them in the plant structure.