OLIVEWASTE. Long term Benefits of the Project

Transcription

1 OLIVEWASTE Long term Benefits of the Project

2

3 LIFE 05 ENV/E/ OLIVEWASTE INDEX 1. Long term Environmental Benefits of the Project Vegetation water recovery Reduction of toxic compounds (benzopyrens) Phase system orujo with low sugar content Total absence of solid and liquid waste Long term Economic Benefits of the Project Indirect Benefits of the Project... 5 Long term benefits of the project i

4

5 LIFE 05 ENV/E/ OLIVEWASTE 1. Long Term Environmental Benefits of the Project 1.1. Vegetation water recovery The following chart shows the major environmental benefit of the project. This benefit involves two main recommendations after analyzing the results: 1. To make the 3-phase extraction process, instead of 2-phase extraction system, which is currently being applied. 2. Treatment of the water obtained after carrying out the 3-phase extraction process. Chart 1: % of vegetation water recovered and evaporated. Approximately 50% of the olive is vegetation water (internal water of olives), which after the olive oil extraction is currently being evaporated into the atmosphere. If the 3-phase extraction is done instead of 2-phase extraction in the olive oil mill, the obtained product is olive pomace with 50% of humidity. Then, after being dried up to its 8% of humidity and subjected to chemical extraction processes in the extraction plants, its remaining oil is extracted. This process produces an evaporation of 33% of the vegetation water coming from olives, instead of the 95% of the vegetation water that is being currently evaporated. Long term benefits of the project 1

6 Project LIFE 05 ENV/E/ OLIVEWASTE In addition, if after this 3-phase extraction system the water obtained by the OLIVEWASTE project would be treated, approximately a 51% of the vegetation water will be recovered. This water could be used to irrigate about 19 ha of olive trees, with an annual allocation of 2000 m 3 / Ha, considering the milling of 150,000 tones of olives Reduction of toxic compounds (benzopyrens) In 2001, there was some pomace oil exported to the Czech Republic with a concentration exceeding 700 ppb of α -benzopyrenes. α -benzopyrenes are mostly incorporated to olive pomace or orujo oil during the drying process (Junta de Andalucía, Agriculture and Fishery Ministry in Andalucía region of, 2001). Polycyclic aromatic hydrocarbons (PAHs) are present in nature, and many of them are originated during the incomplete combustion of organic substances under deficit oxygen conditions and high temperatures (above 300 C). Drying in the extraction plant was traditionally carried out in rotary dryers and continuous trommels, where a circular flow of hot air ( C) coming from orujillo combustion was circulating. However, the amount of water present in the solid waste (alperujo) was increased by the change to a 2-phase system, therefore was also necessary to modify the process. Two possible solutions were: To increase the dryer size and to keep the drying temperature. To increase the drying temperature and to keep the dryer size. The solution applied by most of the extraction plants was the cheaper, without the need of doing large investments. This meant to increase temperature up to C and therefore, to favour benzopyrenes formation. OLIVEWASTE project proposes to do an extraction with the 3-phase system in the olive oil mills, so that the by-product in the extraction plants would contain less water. This would imply the use of lower drying temperatures and therefore the risk of production of this kind of toxic compounds would be lower in the extraction plants Long term benefits of the project 2

7 LIFE 05 ENV/E/ OLIVEWASTE during the extraction process of the olive pomace oil. Moreover, the majority of the water would be recovered in the treatment plants Phase system orujos with low sugar content A part from the problem of benzopyrenes formation due to the high drying temperatures, it must be taken into account that all the sugars, which are present in olives, are trapped in the alperujo. Since high temperatures are required, these sugars are caramelized producing alperujo balls, where the extracting agent (nhexane) can be retained with the consequent danger of explosion. If the extraction is carried out in three phases, most of the olive sugars go to the liquid phase, obtaining orujos with low sugar concentration and avoiding the danger of solvent occlusion in the extraction process Total absence of solid and liquid waste Liquid waste After the treatment process, the water recovered can be used for irrigation or can be discharge into the public courses following the already existing legislation. Royal Decree 1620/2007 and Royal Decree 1 / 2001 (Water Law), respectively. The concentrate produced during the process of evaporation / concentration is used to produce liquid fertilizers of different types according to the Royal Decree 824/2005: Liquid nitrogen mineral organic fertilizer. Liquid NP mineral organic fertilizer. Liquid NK mineral organic fertilizer. Liquid mixture with chelated micronutrients. Long term benefits of the project 3

8 Project LIFE 05 ENV/E/ OLIVEWASTE Solid waste Solid compounds obtained after the Accelerated Solid compounds Separation, are dried to obtain an appropriate humidity (< 60%) by mechanical drying. This drying is carried out in a 3-phase decanter of the plant. Then, they are mixed with pruning waste and olive grove leaves, which contribute to give the suitable structure and improve the C / N ratio. Finally, they are composted to obtain a Vegetable Organic Compost that complies with the legislation in force (RD 824/2005). 2. Long term Economic Benefits of the Project If the olive oil sector of the area carries out the 2 main recommendations of OLIVEWASTE project, the overall economic benefits (expressed per ton of milled olive) would be: Benefits: Transport cost reduction Energy savings Organic solid fertilizers production Liquid fertilizers production Water recovery for irrigation 3-Ph Phase system orujos without sugar Decrease in benzopyrens generation 2,80 /tn olive 2,40 / tn olive 0,04 /tn olive 5,70 / tn olive 0,01 / tn olive Very important but difficult to assess Drawbacks: Alpechines treatment additional costs 4,42 / tn olive Global Economic Benefit for the Sector: 6,53 /tn olive Long term benefits of the project 4

9 LIFE 05 ENV/E/ OLIVEWASTE As it is shown in the table, there is a cost for the alpechín treatment, which is compensated and even exceeded by some income (liquid and solid fertilizers production) and some saving (alperujo transportation cost and energy savings when drying). However, even if this benefit is important in itself, the benefit is more important if we consider the environmental benefits involved. These can not be numerically quantified but in our point of view are really important. There is a more detailed description of the amounts reflected in the table in the final version of the document "Economic Impact Report". The table is only a summary of this document. 3. Indirect Benefits of the Project The idea of Fundación Cartif, Trainalba and Enerman is continuing the research on the approach developed as part of the process of continuous improvement that drives the activities of these entities. With this aim, actions based on the results of the project and on the method used have being prepared and implemented, as it is already mentioned in the Plan for Use and Management of the Demonstration Plant. To perform such work, the plant can be used as a laboratory at pre-industrial or industrial scale, which is an indirect benefit from the project implementation. Among the suggested actions are: 1. Plant performance optimizat o ptimization: Alternative evaporation systems research, which is based on a different technology or combinations of the current technology used in the plant and others. It is intended to further reduce treatment costs through the study of the higher energy consumption part of the process. During the project, work at this point has been done in order to obtain reductions on the theoretical consumption of the prototype. Continuous talks with Alfa Laval in order to Long term benefits of the project 5

10 Project LIFE 05 ENV/E/ OLIVEWASTE convey the experiences of Cartif about thermal concentration systems have been carried out and together they have established a working line in this field. 2. Post-treatment treatment system design for the technology already developed in order to treat current complex waste and to achieve results, which accomplish the current legislation: Combinations of systems (advanced oxidation, ozonation, membranes, etc.) will be tested. The aim is to establish a feasible technically solution for "tough/harsh waste, which even if it is in minor quantities, it is often the most damaging. 3. Development of innovative and cost efficient techniques: Allowing water recovery for irrigation coming from liquid waste of food industry, reversing in this way, the unsustainable trend that is being carried out at the present. It is important to mention that the developed method in this project is believed to be successful, when established in some other industries where waste is produced. This method has features that give it an important flexibility to deal with different kinds of residues. For example: the possibility of implementing it in vegetable washing water within the industry of food processing. 4. Obtaining Additives with antioxidant properties from waste and/or by-products of Agro-Food Industry: I Starting with olive oil mills, but it could be expanded to other Agro-Food industries. This approach is designed to provide profitability to the waste treatment and to provide waste some value. For instance, currently we are working on a project to devise a method for polyphenols extraction from such waste. Long term benefits of the project 6