LIFE09 / ENV /ES/ CITROFUEL Demonstration project on a new process for secondgeneration bio fuel production: bio ethanol from citrus flesh.

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1 LAYMAN S Report LIFE09 / ENV /ES/ CITROFUEL Demonstration project on a new process for secondgeneration bio fuel production: bio ethanol from citrus flesh.

2 ENVIRONMENTAL PROBLEM Spain is Europe s largest producer of citrus fruit in Europe with an output of 6 million tones/yr. Some 1.6 million tones/yr of this total goes into the production of fruit juice, it means that only in Spain around of tones of peel and pulp waste are generated yearly. This is highly problematic waste for the environment. The only existing alternative to land filling of citrus fruit waste is its use in fresh animal feed. However, the high content of water in the fruit wastes between 78% and 82% - means both high transport costs and leakage of contaminating liquids which can ferment and contaminate the aquifers. 2 Desiccation is often used to treat citrus waste. However, problems arise from the high biological oxygen demand (BOD) values of the wastewater generated in the process, which are very difficult to treat, together with the high energy demand of the process. Additionally, this process is only aimed at the reduction of transport costs rather than an integral valorization of the waste. Together with this problem, the Action Plan on Biomass [COM (2005) 628 final] established a new point of view regarding the EU energy policy and stated that waste was/is, generally speaking, sub-exploited as a renewable energy source. In line with this approach, CITROFUEL project had change the environmental problem of the citric waste management, in an ecological and sustainable solution as is the production of bioethanol of second-generation by using peel and pulp waste. In this case neither cereal, nor other product for human consumption is used in the manufacture of bio-fuel which is, obviously, second generation bio-ethanol. This approach is in line with the 'EU Strategy for Bio-fuels "[COM (2006) 34] final, regarding the role of the bio-fuels derived from biomass as source of renewable energy as an alternative to fossil energy sources being used by the transport sector. In that sense, while a gasoline engine emits (on average) 180 gr. CO2

3 per km, a bio-ethanol engine emits only around 70 gr. CO2 per km. At EU level, it is foreseen that in 2020, bio-fuel consumption account to 10% of energy sources. THE CITROFUEL PROJECT ( The project s main objective is to test and to start a new process to improve /optimize the management and sustainable use of natural resources and waste, improving its prevention, recovery and recycling through the construction and set up of an industrial prototype for producing bio-ethanol from flesh (biomass) generated through citrus industrialization (juices production, etc) by means a new fermentation process. In this case neither cereal, nor other product for human consumption is used in the manufacture of bio-fuel which is, obviously, second generation bio-ethanol. This approach is in line with the 'EU Strategy for Bio-fuels "[COM (2006) 34] final, regarding the role of the bio-fuels derived from biomass as source of renewable energy as an alternative to fossil energy sources being used by the transport sector. At EU level, it is foreseen that in 2020, bio-fuel consumption account to 10% of energy sources. 3 THE BENEFICIARY: CITROTECNO. Being aware of the problem caused by citrus waste, a group of Valencian business people, involved in farming and livestock, set up the Picima Inversiones business group, from which CITROTECNO, S. L. was created. CITROTECNO was born with the objective of establishing a citrus waste treatment by using citric flesh to manufacture pellets for animal feed and together to that to explore the utilization of fluids coming of the pellets manufacturing process to produce bioethanol with a technology developed at the Polytechnic University of Valencia solving the problem of citrus waste. THE TECHNOLOGY AND THE INNOVATION CITROTECNO produces basically raw material for animal feed; together to that the project permitted to obtain D-Limonene essential oil and second generation bioethanol. Moreover, most of the water content in the waste is recovered.

4 On the whole, the process, which is very complex, starts with the receipt of the citric residue through a hopper capacity of 22 m3, located on the outside of the plant. From here the raw material is sent to a second hopper storage where will manage you lime in a portion of 0.3 to 0.6% to make alkaline product and facilitate their processing. After the reaction with lime, product crushes through the action of a hammer mill. Already shredded product shall be subject to a double-pressed through a system of horizontal presses. By means this process of pressing two by-products are obtained: 1. The first by-product is the pressed cake (which is not part of the LIFE+ CITROFUEL project) or solid fraction with 70% humidity which undergoes a process of dehydration by hot air drying of Rotary type tunnel. Gases generated in the burner cross the tunnel and van loading water vapor as van drying product. Drying results again two products: 4 a. The bark or dry waste. Obtained dried crusts are very dusty nature, reason why chose to transform them into granules or compact pellets, which reduces the volume of the product and makes its final management more efficient and clean. After his compacted, the final product is stored in conditions of temperature and humidity controlled in order to preserve its stability. b. Exhaust gases loaded with filtered humidity to his end of the tunnel drying by cyclones. On the other hand, exhaust temperatures from drying tunnel take advantage as a source of energy for the functioning of the heat sink system residual energy (WHE) or multiple

5 effect evaporator. Exhaust drying cedes its heat and cooling will condense water containing. This water wears in part for the washing of gases at the entrance of the evaporator and part is stored along with the water condensed at other times of the process. 2. The second by-product (which is the core part of the LIFE+ CITROFUEL project) is the liquid fraction or spirits of crimp is collected in a tank where it is filtered and stored to your back foot. This fraction is used for the Bioethanol production and is a line that operates in parallel and attached to the line of dehydration and, it is said, employs as premium spirits obtained from the pressing citrus waste process. 5 These pressing liquors are rich in fermentable sugars which, subject to certain yeasts, metabolic action are transformed into ethanol using a process similar to the manufacture of wine. Currently it is necessary to dilute present liqueur pressing essential oils because they inhibit the growth of yeasts. Oil separator system that uses steam to drag the essential oils used to do this. At the end of this step three products are obtained: Steam with D - Limonene leading towards the evaporator for the recovery of D - Limonene by condensation. A non-volatile fraction or delicious is stored for later use in the line of dehydration, and Wort (liquor containing fermentable carbohydrates coming from citric residue which must be prepared for the fermentation process by adding water, sulphuric acid and nutrients after fermentation. At the end of the fermentation

6 process it gets a fermented means or wine which, once heated, passes through a distillation column to concentrate it generating a volatile fraction containing Bioethanol that will focus until you get a solution with 80% ethanol. Once cooled, this product is stored and conditioned for later management. THE RESULTS OF THE PROJECT The main project s objective has been achieved very satisfactorily as it has been possible to design, to construct, to set up and to validate the functioning of the prototype industrial plant to manufacture bio-alcohol by means a new process based on the fermentation of byproducts of the pulp of citrus which is generated in different process of agro-food industry ( THE IMPACTS&BENEFITS ENVIRONMENTAL IMPACT. From an environmental point of view the new process has a positive impact as, according to the results achieved, the use of bioethanol as a transport fuel has two distinct advantages over gasoline: lower consumption of fossil energy in its production and distribution, thereby increasing the duration of oil reserves 6 Savings of 0.25 TOE per tonne of peel and pulp waste of citrus fermented. And, on the other hand, Savings in emissions of greenhouse gases (GHG) in the range of 0.78 tonnes of CO2 equivalent per tonne of peel and pulp waste of orange treated. The project is, from these points of view, highly relevant to the European environmental policy and legislation The EU's Sixth Environment Action Programme (EAP), "Environment 2010: Our future, Our choice", includes to ensure that the consumption of renewable and non-renewable resources does not exceed the carrying capacity of the environment and to achieve a decoupling of resource use from economic growth through significantly improved resource efficiency and the reduction of waste. With regard to waste, the specific target is to reduce the quantity going to final disposal by 20 % by 2010 and 50 % by Communication From The Commission To The Council, The European Parliament, The European Economic And Social Committee And The

7 Committee Of The Regions: Thematic Strategy on the sustainable use of natural resources (COM(2005) 670 final). The objective of the strategy is to reduce the environmental impacts associated with resource use and to do so in a growing economy. Focusing on the environmental impacts of resource use will be decisive factors in helping the EU achieve sustainable development. The project s development and its results proved that it is possible to reduce the environmental impact of the agro-industrial sector as it is possible to achieve huge reduction in waste production. ECONOMIC BENEFITS. The project demonstrates the technical viability of the process although, from a financial and economic point of view, it will be necessary working to increase conversion ratio index bioethanol vs. wort put into fermentation, at this stage, is still too low, around 0.04 l bioethanol (99.99GL) /l of wort. This circumstance, together with the low price of the bioethanol, makes difficult, at least currently, to think about adapting the process at industrial scale. TRANSFERABILITY The solutions of the project are very advantageous from an environmental point of view and prior works should permit to avoid economic difficulties pointed out above. Nevertheless, 7 The interest for the CITROFUEL-project and for the solution it offers has been overwhelming from other stakeholders. The potential to implement the technique at European level seems to be remarkable. All contacts made throughout the project s implementation shown great interest for the project.