We are working on innovative technology to fix CO2 through the cultivation of microalgae. In the Research Centre for Renewable Energy and the Environment in Novara, together with the Politecnico di Torino and Italian start-ups, we are developing a biofixation technology where algae are fed by artificial light using the best wavelengths for photosynthesis. The vegetable biomass which is produced, collected and dried, is an algal flour that can be used as a product or component for agro-industrial, food and/or nutraceutical markets. It can also be used to extract bio-oil, while the water, once purified, can be put to other uses. The nature of the algal bio-oil obtained from this process makes it ideal to be transformed into the biodiesel which we use to boost our Eni Diesel+.
Finding new ways to reuse carbon dioxide in industrial processes is part of the strategy to reduce the emissions of climate-changing gases. Such operations use the circular economy approach, which already features in our business model, to allow them to “close the anthropic carbon cycle”, Here, through the natural photosynthesis process, CO2 molecules are biofixed by microscopic algae, intensively cultivated in photobioreactors. This technology gives us both the possibility to reduce emissions in our business sectors, using them to cultivate algal crops, and to make use of areas which cannot be used for agricultural purposes, not to mention the opportunities for local development that launching business initiatives based on these plants could bring to the area.
Like all plants, algae need the sun to grow. However, they are real living cells, in fact they reproduce by mitosis. It's possible to intensify and make their growth pattern more efficient, for example by using one or more specific light frequencies. As part of our technology development activities at the Research Centre for Renewable Energy and the Environment in Novara, and together with the Politecnico di Torino and Italian start-ups, we have created multilayer photobioreactors which feed the algae with light from an LED system, which guarantees uninterrupted 24-hour operation at any latitude. This LED system emits light at the optimum wavelengths for algae photosynthesis, maximising their growth processes. Being able to run uninterrupted day and night allows the plant to produce as much as 500 tonnes of biomass per hectare per year, consequently trapping 1000 tonnes of CO2 . Eni has already previously researched CO2 biofixation with microalgae using sunlight, both in open pond (at the Eni Refinery in Gela) and in photobioreactors (at the Enimed site, in Ragusa). In the latter case, the research was based on technology from BioSyntex Srl (BSX), which involved the cultivation of microalgae fed by CO2 from activities managed by our subsidiary EniMed and concentrated sunlight with panels made up of thousands of Fresnel lenses that follow the sun and concentrate its rays in special optical fibres.
The industrial development of biofixation technology is part of our strategy to decarbonise our assets. Being able to use the CO2 from our activities and convert it into marketable products gives us the double advantage of reducing emissions and making new sustainable products available on the market. This initiative is currently at the advanced experimental stage required to optimise each step and maximise the efficiency of the entire process. Once we have built industrial scale production systems based on this technology, the areas of application could be diversified into agro-industrial, food and/or nutraceutical markets, and for our own business. Because of its particular design, the artificial light technology photobioreactor system has a reduced carbon footprint and is modular, meaning it can easily be installed in many types of industrial site, wherever there is carbon dioxide to be captured.
Catturare CO2 per produrre bio-olio algale - #innovation4energy | Eni Video Channel
The strengths of microalgae decarbonisation technologies are their low energy consumption, high efficiency, simplicity, modularity and compactness and, with the use of optimised wavelength LEDs, 24/7 uninterrupted operation. These factors make them suitable for applications in the most varied of contexts and compatible with the different operational scenarios that might be encountered in the energy industry. Once they have been developed on an industrial level, these plants could make a significant contribution to reducing the CO2 emissions generated by our upstream operations and other industrial sectors, with the added bonus of obtaining a finished product such as algal flour, which can be used in the downstream sector or sold for use in other production processes. Both of these factors mean that these technologies could be adopted on a broad scale, thus boosting the potential positive impact that it could have in terms of limiting carbon dioxide emissions.
Data, performance and results
Growing seasons reproduced per year
250-450 ton/year per hectare
Algal floor produced
450-1170 ton/year per hectare
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