domenica 11 aprile 2021

nuovi carburanti per la green economy

 Il post di oggi riprende il discorso degli inerventi per mitigare i cambiamenti climaici. In paricolare, abbiamo introdotto la produzione di biochar, o carboni vegetali, mediante gassificazione e flash-pirolisi, un processo che produce syngas (ossido di carbonio, idrogeno gassoso, e altri prodotti alifatici). 

Il processo è descritto in questa immagine (6.3)


come materia prima, abbiamo parlato di biomasse vegetali, scarti, segatura, ma anche materiale solido derivante dalla raccolta differenziata della spazzatura.
Molti di questi impianti di produzione su grande scala sono asssociati a finanziamenti EU di progetti pilota. 
Segue presentazione in lingua inglese. Renewable energy sources include wind power, solar power (thermal, photovoltaic and concentrated), hydroelectric power, tidal power, geothermal energy, biomass and the renewable part of waste.
The use of renewable energy has many potential benefits, including a reduction in greenhouse gas emissions, the diversification of energy supplies and a reduced dependency on fossil fuel markets (in particular, oil and gas). Biodiesel life cycle analysis (LCA) shows it affects a 78 % reduction in CO2 (greenhouse gas) emissions relative to petro diesel.
Targets in EU Commission define that only seven-tenths of renewable energy will originate from first-generation fuels. The difference of three-tenths will be made up by second generation fuels, advanced fuels based on waste products and other feedstocks that do not affect food production. That translates in European demand for advanced biofuels to reach 14 billion litres by 2020. Only two types of advanced fuels are capable of large-scale production today in Europe. 
The first one is based on turning waste cooking oil and other fats into diesel. Europe already has 2 billion litres of capacity to process these by-products. 
The second type of plants are producing ethanol from cellulose by enzymatic hydrolysis.
A number of EU projects addressed the feedstock issue, eg. ITAKA project improving the readiness of existing technology and infrastructure: focus on camelina & cooking oil. Oil from plants is extracted, hydrocracked, products are isomerised to obtain paraffins and iso-paraffins.
Several EU projects have been funded to provide solutions to the challenge of feedstock processing.
In one such project, the EMPYRO consortium was led by BTG.Bio-oil, for combined heat and power (CHP) and acetic acid at AkzoNobel Global, The Netherlands, a Multi-national manufacturing corporation, active in healthcare products, coatings and chemicals. The EMPYRO pyrolysis oil plant of Biomass Technology Group in the Netherlands was the first EU plant to sign a long term supply contract of the bio-oil to replace fuel oil. In EMPYRO, full conversion configurations have been estimated for a range of economies of scale, 1 MW, 675 MW and 1350 MW LHV of bio-oil. The economic competitiveness was found to increase with increasing scale. A cost of production of FT liquids of 78.7 Euro/MWh was obtained based on 80.12 Euro/MWh of electricity, 75 Euro/t of bio-oil and 116.3 million Euro/y of annualised capital cost (Ng and Sadhukhan 2011).
In another project, the LED consortium, was led by Abengoa industries. To produce from straw and maize bioethanol and renewable hydrocarbons. The CHEMREC Bio-DME project has been the first project to demonstrate the conversion of black liquor to bio-dimethyl-ether, through the production of synthesis gas which is converted to second generation biofuels. Black liquor is a waste product resulting from the conversion of pulpwood into paper pulp. Dimethyl ether is an advanced biofuel
produced by catalytic dehydration of methanol, or from syngas. Above -25°C or below 5 bar, DME is a gas. Hence its use as a transport fuel is similar to that of Liquid Propane Gas.
InteSusAl is a still ongoing EU project. Three European algae biofuel projects with a common LCA approach. Three large scale algae production facilities are under development. These will be the largest facilities built in Europe; with a productivity of 90 tonne/hectare of dry matter algal biomass per year for each facility (30 hectares totally).
Infinite Fuels GmbH works on the development and market introduction of a unique technology for transformation of renewable electricity, biomass and waste into sustainable hydrocarbons serving as basic chemicals and fuels. The incubator for start ups KIC InnoEnergy Germany, has signed five new German start-ups under its Business Creation Accelerator programme (KIC InnoEnergy’s Highway).
The companies were selected by a committee of experts for their ability to innovate, as well as potential to drive Europe’s move towards sustainable energy with high-performance and efficient products.
Syngas e pirolisi
Lignocellulosic residues are hydrolised into sugars and charcoal, processed into syngas, that together with alcohols are hydrocracked and isomerised to obtain paraffins and iso-paraffins, with aromatics and cyclo-paraffins.
There are several types of biofuels.
SKA are synthetic paraffinic kerosene with aromatics-  as a blendstock with conventional jet fuel.
FSK are Fully Synthetic Kerosene. This fuel falls within the conventional jet fuel specification- to be used as neat jet fuel.
SIP, a synthesized iso-paraffine, C15, is obtained from from farnesan, a sugar molecule ( component for blending with conventional jet fuel)
Hydroprocessed oils and fats (HRJ/HEFA) are converted into kerosene-like fuel (SPK), a synthetic paraffinic kerosene used as a blendstock with conventional jet fuel.
ATJ = fuel produced from C2-C5 alcohols, as single alcohol or multicomponent mixture, into kerosene like fuel and kerosene (SPK, SKA, FSK).
Overview of the process to produce kerosene-like fuel (SPK). Coal and biogas are gassified into syngas, then n-paraffins are synthesised through the Fischer Tropsch (FT) process and hydrocracked and isomerised to obtain paraffins and iso-paraffins as kerosene-like fuel (SPK ). In the FT process, the purified syngas is processed through a fixed-bed tubular reactor where it reacts with a proprietary catalyst to form three intermediate FT products, a Heavy Fraction FT Liquids (HFTL) product, a Medium Fraction FT Liquids (MFTL) product and a Light Fraction FT Liquids (LFTL) product, commonly called Naphtha. The Naphtha is recycled to the partial oxidation unit with remaining tail gas to be reformed to hydrogen and carbon monoxide.
"Production of fully synthetic paraffinic jet fuel from wood and other biomass " BFSJ 612763 is a project in the EU 7th Framework Programme (2007-2013) involving Swedish Biofuels.
Full scale commercial plant size was estimated to be 200,000 ton/y of motor fuel, of which jet fuel would make up 100,000 ton/y. The business plan is to deploy 3 commercial units in the 10 years following the project, subject to market acceptance, safety and financial risks. With a good political and economic environment, up to 600,000 t/y of advanced biofuels can be produced by 2030 using Swedish Biofuels ATJ technology: Production is economic at various production volumes, e.g. processing 2,500,000 m3/y of humid, low grade wood residues. A wide range of biomass suitable for process is available. Biological fuel capacity: 30 t/y (3300 USGallons/y). Jet 14.4 t/y. Gasoline 10.5 t/y. Diesel 5.1 t/y.
A third type of biofuel is under development using municipal solid waste (MSW) as source of lignocellulose.
Key market drivers for waste as feedstock are of various nature, here enumerated: increased scarcity of urban landfill space and societal desire for waste diversion; Turning carbon waste into a useful building block for the chemical and petrochemical industry; low cost, non-land using, unconventional feedstocks for biofuels and renewable chemicals; renewable fuels mandates around the world;
consumer pull for renewable and biobased products; focus on carbon footprint and greenhouse gas emissions reduction.
The potential for transforming garbage (estimated valued are positioned around 254 Million metric tonnes/year in Europe) into chemicals and fuels (375 litres of cellulosic ethanol per metric tonne) is delineated in Figure 6.2.

There are ongoing strategic alliances with EU and partners around the world, by Enerkem biorefineries (full-scale commercial biorefinery in Edmonton, and two facilities in Quebec, Canada), a producer of biofuels and renewable chemicals from municipal solid waste, agriculture biomass, plastics, petcoke, biosolids from pulp and paper industry, forest biomass and wood pellet.
Enerkem has a proprietary clean technology developed in-house. The thermochemical process converts MSW feedstock into low-carbon renewable transportation fuels including jet fuel and diesel.
Fulcrum, US,  is a pioneer in the development of a reliable and efficient process for transforming everyday household garbage into low-carbon transportation fuels including jet fuel and diesel. The low-cost process reduces the dependence on imported oil, create new clean energy jobs and significantly reduce greenhouse gas emissions compared to traditional petroleum production.
Fulcrum has established industrial partnership with US Renewables Group and Rustic Canyon Partners, two leading venture capital firms in the clean energy space. In addition, Waste Management and Cathay Pacific Airways have become equity partners in the Company. Fulcrum ThermoChem Recovery International has licensed to Fulcrum their highly efficient and economic gasification system for the conversion of the carbon rich residues into synthetic gas (syngas) (Figure 6.3). During the gasification process, the prepared MSW feedstock rapidly heats up upon entry into the steam-reforming gasifier and almost immediately converts to syngas. The syngas is further cooled in a packed gas cooler scrubber. The cleaned syngas is then processed through an amine system to capture and remove sulfur and carbon dioxide. The syngas then enters the secondary gas clean-up section that contains compression to increase syngas to the pressure required by the FT process.
The syngas is catalytically converted, thus synthesing the renewable fuel constituents.
Utilizing this transformation process, municipalities will be able to convert the garbage into 30 million gallons per year of clean renewable fuel. A number of facilities are under construction across North America with the annual capacity to produce hundreds of millions of gallons of renewable transportation fuel while eliminating trash landfilled annually across North America.
In 2015 Fulcrum announced that it had awarded an engineering, procurement and construction contract to Abengoa for the construction of the Sierra BioFuels waste to transportation fuels plant.
Abengoa will construct Sierra under the fixed-priced contract that also includes cost, schedule and plant performance guarantees.
In US, United Airlines (UA) has announced the first stable use in the tract from Los Angeles-San Francisco, by as new jet fuelled with bio-kerosene. The required amount of fuel at this stage is 180 million litres each year. In the agreement with UA, Fulcrum will transform Municipal Solid Waste (MSW), cooked oils and fats derived from animal wastes to produce a biofuel that will be blended with traditional fuels.

Aviation Climate Change Commitments are exemplified in Figure 6.4. 

There are several targets to be accomplished, such as an improvement of 1.5% fuel efficiency per year from 2009 to 2020; a Carbon neutral growth from 2020; a reduction of net emissions by 50% by 2050 compared to 2005 levels.
Air transport moves over 2.4 billion passengers annually, dumping 677 million tons of carbon dioxide into the atmosphere. While these emissions are small compared with other industry sectors, these industries have viable alternative energy sources. The power generation industry can look to wind, hydro, nuclear and solar technologies to make electricity without producing much CO2. Cars and buses can run on hybrid, flexible fuel engines or electricity. The primary objective of using biofuel is to
reduce emissions. Carbon Dioxide absorbed by plants during its growth is roughly equivalent to the amount of carbon produced when the fuel is burned. This would allow biofuel to be carbon neutral over its life cycle.
The European Biofuels Flight Path Initiative (EBFPI) and the European Biofuels Technology Platform (EBTP). The EU Commission has launched the EBFPI with the objective to reach the target of using 2 MTons of aviation biofuels in 2020, corresponding to about 4% of EU fuel consumption. By 2015, EBFPI will set up financial mechanisms, secure sustainable feedstock production to feed three refineries, construct three new refineries, and launch biofuel production. By 2018, EBFPI will start regular commercial flights using biojet fuel blends, construct four additional refineries, and construct two additional refineries producing algal and microbial oil-based aviation biofuels. By 2020, a full deployment of at least 2 million tons of biofuels per annum for EU aviation
Sunchem has made an alliance with SkyNRG and South Africa Airlines (SAA) for the exploitation of Solaris. SkyNRG expanded production of the hybrid Solaris as an energy crop that farmers could grow instead of traditional tobacco. South African Airways (SAA), Boeing, and SkyNRG are developing bio-jet fuels. South African Airways (SAS) is partnering with Boeing aerospace company and Amsterdam-based SkyNRG to make sustainable aviation biofuel from a new type of tobacco devoid of nicotine, the
Solaris variety of tobacco, grown in South Africa.


 Resource Technology Strength. 
Bioenergy and advanced biofuel investments are in  progress. 
In the US, Boeing has partnered up with other stakeholders to promote “Farm to Fly” biofuel programs that includes the Midwest Aviation Sustainable Biofuels Initiative (MASBI) along with United Airlines, UOP (a Honeywell company), the Airlines for America (A4A) Inc., the Chicago Department of Aviation, the Federal Aviation Administration (FAA) and the Clean Energy Trust.

The US National Bioeconomy Blueprint is designed to create jobs and stimulate investment by using federal resources to speed the transition from fossil fuel dependency into a more sustainable, healthful and diversified mix of fuels, chemicals and other products.
Boeing has been looking for partners at various levels, including fuel from plants grown in the desert using saltwater, and it is optimistic that a range of bio-kerosene promising to be both cleaner than standard fuels and with a greater energy density, essentially offering more power for less weight, is to be certified for aviation use.
Currently, these alternative fuels for transport are marketed by Neste Oil and by ENI. In 2014, Neste Oil produced approximately 1.3 million tonnes (1.6 billion litres) of renewable NEXBTL diesel from waste and residues. There is a big potential for aviation since three refineries in function, one in Italy, one in Rotterdam and one near Helsinki currently produce around 4 billion liters of bio-kerosene. This amount for aviation corresponds to 2 percent of fuels use globally.
Boeing Airlines have conducted more than 1,500 passenger flights using biofuel since the fuel was approved in 2011. Alternative aviation biofuel reduces carbon emissions by 50 to 80 percent compared to petroleum jet fuel through its life cycle.

Military Certification Constraints
ASTM approval of a synthetic fuel means that blend with synthetic fuel conforming to specification is considered Jet A/Jet A-1 fuel, can be used by any civil aircraft certified for use of Jet A/Jet A-1, and is accepted both within North America and Europe. This, however, does not imply certification for military use. The military is using its own fuel specifications. A military equivalent to Jet A-1 exists (JP-8), and NATO aircraft are qualified on it.
US Armed Forces have introduced advanced regulatory rules so that FT- and HEFA-kerosene have been approved for all military equipment. US Armed Forces increasingly move to include blends with synthetic material in their fuel supply
approval process is coordinated by US standards body ASTM, referring to relevant specification such as ASTM D7566. This defines required properties of blends of conventional (ASTM D1655) kerosene and synthetic material. The specification annexes define required properties of the neat synthetic fuels (currently three), Fischer-Tropsch (FT) with maximum blend ratio 50%; Hydrotreated Esters and Fatty Acids (HEFA) with maximum blend ratio 50%; Farnesane (SIP) with maximum blend ratio 10%. Fuel meeting ASTM D7566 by definition becomes ASTM D1655 kerosene, and can use the same infrastructure as conventional fuel.
Implications for biokerosene. In case of aviation kerosene, registered substance is defined as ‘‘being produced from crude oil sources‘‘. Kerosene not produced from crude oil still needs a separate registration. This makes the process expensive and time-consuming, costing several 100,000 Euros.
Full registration of bio kerosene so far has only been performed by Neste Oil, for HEFA.
Whereas ASTM D7566 conforming blends are within the experience base for conventional kerosene, the synthetic components are dissimilar. Main components of conventional kerosene are n- and iso-alkanes, cycloalkanes and aromatics. HEFA- and FT-kerosene consist almost solely of n- and iso-alkanes. Other pathways currently up for approval produce fuel solely consisting of aromatics, fuel consisting of cycloalkanes and aromatics, or even fully synthetic fuel containing all main components of conventional kerosene (SIP kerosene is an extreme case, consisting solely of C15 iso-alkanes).
In the aviation approach, blend is the key unit. Certification is released on the basis of blend properties, that Need to be within experience base for conventional kerosene. If D7566 conditions are met, blend by definition becomes D1566 fuel. Information of synthetic component is completely lost (US) or only generically preserved (Europe). Properties of individual blend components are defined only for quality control purposes. The rationale is that only the blend will ever end up in an aircraft.
da:
Polronieri P. Tobacco seed oil for biofuels. Pp. 161-187. In: Polronieri and D'Urso: Bioransformation of agricultural waste and by-products. The  food, feed, fibre, fuel (4F )economy. Elsevier 2016.

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Questo blog non rappresenta una testata giornalistica in quanto viene aggiornato senza alcuna periodicità . Non può pertanto considerarsi un prodotto editoriale ai sensi della legge n. 62 del 7.03.2001