With the introduction of the two-phase system in olive mills, vegetation water was incorporated into the pomace, doubling the amount of water that needs to be evaporated to reduce its moisture content before processing. the extraction of pomace oil using food-grade solvents. Traditionally, the thermal energy for this process comes from the combustion of degreased olive pomace, which generates ash and emissions that must be removed using cyclones or the more expensive electrostatic precipitators.
Pyrolysis is presented as an innovative alternative that, using the same biomass, generates biochar instead of ash, providing a new added value that allows the investment in pyrolysis plants to be recouped in just a few years. Espuny assures that “The 60% pomace is currently dried using traditional ovens that could be replaced by pyrolytic ovens.”.
Since 2020, CARBOLIVA It operates an 8 MWt furnace where the 6-7 tons per hour of steam needed by the Coosur-Acesur pomace extractor in Puente del Obispo (Jaén) is generated, also producing between four and five thousand tons of biochar per year. “This is the first plant in the world to operate using olive pomace,”, Espuny points out, adding that the forecasts are “to install 20 furnaces of 10-12 MWt in the next 10 years.” This would involve the carbonization of 600,000 tons of biomass per year, generating between 180,000 and 200,000 tons of biochar, which would contribute to reducing more than 400,000 tons of CO2.
Furthermore, the company has established long-term agreements to set up operations in host plants and provide the service of pyrolyzing biomass (mainly bone and pomace, without ruling out others such as almond shells) and supplying clean thermal energy without requiring new investments from its partners.
An example of circularity taken to its highest expression
The concept of a circular economy is central to Carboliva's operations: "The olive tree captures CO2 from the atmosphere, fixing it in its roots, leaves, and branches. It also fixes it in the olive, whose biomass, after oil extraction, we transform into biochar," Espuny points out.
By applying biochar to the soil or integrating it into other materials such as compost, concrete, asphalt, slurry, or the digestate from biogas plants, it establishes «"a robust and efficient system to sequester carbon and ensure that it does not return to the atmosphere for hundreds or thousands of years"», explains
The company has become the first in Spain to obtain certification from the EBC (European Biochar Certificate) organization, which controls the production parameters of biochar and its traceability and quality and calculates the carbon footprint, studying the complete life cycle of the biomass and pyrolysis up to the application in the soil.
This certification allows Carboliva to participate in the voluntary trading of emissions allowances, which represents approximately one third of the value of biochar. This additional revenue will allow the company to reduce the price of biochar for farmers, facilitating its marketing in the coming years.
In addition to its role in carbon capture, the biochar It is especially valuable for improving the resilience of agricultural soils to drought due to its ability to retain water and improve soil structure. “Its high porosity is used by microorganisms that live in symbiosis with the roots to shelter and reproduce.”, Espuny adds.
Markets for biochar
Initially, the biochar Carboliva's product was previously used to manufacture barbecue briquettes, but now it is targeting more promising markets such as industries seeking more sustainable alternatives to anthracite and petroleum coke. Furthermore, the company is involved in European projects studying the benefits of biochar in various crops and is attentive to the growing demand in northern Europe for applications in agriculture and animal feed.
Espuny sees great potential in industries such as construction, industrial livestock farming, and the manufacture of "green steel," where “Companies are making an effort to decarbonize their processes and, while they decide on the most appropriate investments, it is relatively easy to switch from burning mineral coal to burning charcoal,», explains.
In construction, the biochar It is integrated into concrete and asphalt to reduce the carbon footprint, and in industrial livestock farming it can decrease emissions and improve manure management. Espuny points out that «"It has been shown that biogas production improves its efficiency when a percentage of porous biochar is mixed in, which increases the contact surface and reduces odors and leachate.".
The company expects to launch its first drying project soon to meet growing customer demand. For now, it has centralized the storage and processing of the biochar in its warehouse in Puente del Obispo and in a future plant in Carmona.
In the future they plan to manufacture activated carbon with biochar renewable energy, a market that relies heavily on imports from Asia. «"Another interesting option for very high-quality coal is the manufacture of energy storage batteries."», He adds that it is a vital sector to support the generation of renewable energy.
Regarding the project's relevance to investors and funders, Espuny highlights the robustness of the model. “which is based on the need of a sector to valorize by-products in a sustainable way» which ensures a constant supply of biomass in exchange for clean thermal energy.
Furthermore, as long as it is necessary to replace fossil fuels with renewable options, a market for biochar will exist. Espuny also mentions that in 2025 the European Union will approve legislation to regulate carbon trading, in which the Biochar Carbon Removal (BCR) system will play a prominent role. «"The 80% carbon capture systems are carried out through the application of biochar to the soil"», He concludes by emphasizing the safety and effectiveness of this method.
https://www.avebiom.org/sites/default/files/biomasanews/BIOMASANews-10-SEP2024.pdf