Jatropha curcas or Physic nut is a perennial poisonous shrub (normally up to 5 m high) belonging to the Euphorbiaceae  family. It is an uncultivated non-food wild-species.

It’s a perennial shrub ( life cycle 20 - 30 years), easy to adapt in marginal areas and moderate regimes of annual rush (350-700 mm). It is resistant to a medium-long periods of dryness (it can be planted even in semi arid areas) and  the products are not edible.

The plant, originating in Central America, whereas it has been spread to other tropical and subtropical countries as well and is mainly grown in Asia and in Africa. It is used as a living fence to protect gardens and fields from wild animals.

 

Seeds production starts rapidly in 6/9 months; the plant reaches maturity after 5 years and it remains in constant production for 20 - 25 years. The seeds contain 28-36% oil (average: 32%) that can be processed to produce a high-quality biodiesel fuel, usable in a standard diesel engine. In good conditions the plant can produce 2 tons of oil per hectare (6 tons of seeds).


Jatropha cake or meal (co-extraction products) can be used as solid biomass for the production of energy or as fertilizer.


Cultivation

 

Cultivation is uncomplicated. Jatropha curcas grows in tropical and subtropical regions. The plant can grow in wastelands and grows on almost any terrain, even on gravelly, sandy and saline soils. It can thrive on the poorest stony soil and grow in the crevices of rocks. Complete germination is achieved within 9 days. It is usually propagated by cutting and  this yields faster results than multiplication by seeds but reduce rooting affecting arid resistant.

 

 

 

The flowers only develop terminally (at the end of a stem), so a good ramification (plants presenting many branches) produces the greatest amount of fruits. Another productivity factor is the ratio between female and male flowers within an inflorescence (usually about 1 female to 10 male flowers - more female flowers mean more fruits). Jatropha curcas thrives on a mere 250 mm (10 in) of rain a year, and only during its first two years does it need to be watered in the closing days of the dry season. Ploughing and planting are not needed regularly, as this shrub has a life expectancy of approximately forty years. The use of pesticides and other polluting substances are not necessary, due to the pesticidal and fungicidal properties of the plant.
While Jatropha curcas starts yielding from 9–12 months time, the effective yield is obtained only after 2 - 3 years time.
If planted in hedges, the reported productivity of Jatropha is from 0.8 kg. to 1.0 kg. of seed per meter of live fence. The seed production is around 3.5 tons / hectare (Seed production ranges from about 0.4 tons per hectare in first year to over 5 tons per hectare after 3 years).


Propagation

Jatropha curcas is usually propagated by seed. It is cross-pollinated and propagation through seed leads to a lot of genetic variability in terms of growth, biomass, seed yield and oil content. Jatropha curcas can be propagated by seed as well as vegetatively.  Vegetatively, this crop can be propagated by stem cuttings, grafting, budding as well as by air layering techniques. The investigation leads to the recommendation that cuttings should be taken preferably from juvenile plants and treated with 200 micro gram per litre of IBA (rooting hormone) to ensure the highest level of rooting in stem cuttings of Jatropha curcas.

Processing

 

 

Seed extraction is made simple with the use of the Universal Nut Sheller; Oil content varies from 28% to 36%. The oily seeds are processed into oil, which may be directly used to fuel combustion engines or may be subjected to transesterification to produce biodiesel. Jatropha oil is not suitable for human consumption, as it induces strong vomiting and diarrhea.

 

 

View all Jatropha mechanical process

 

 

 

 

 

Jatropha Oil 

 

When jatropha seeds are crushed, the resulting jatropha oil can be processed to produce a high-quality biodiesel that can be used in a standard diesel car.

The development of the non-edible oils market in the last few years has been due almost completely to the increasing demand for biofuels. Among the non-edible a major role has been acknowledged to Jatropha oil thanks to its physical and chemical characteristics. In fact, from Jatropha oil it possible to produce a Biodiesel meeting the restricted specifications of the EU 14214.
Moreover the oil fits also well within the specifications requirements of the main providers of endothermic engines for electricity and heat generation able to run straight on vegetable oil (Wärtsilä and Man).

Aviation fuels may be more widely substituted with biofuels a such as jatropha oil than fuels for other forms of transportation. There are fewer planes than cars or trucks and far fewer jet fueling stations to convert than gas stations. On December 30, 2008, Air New Zealand flew the first successful test flight with a Boeing 747 running one of its four Rolls-Royce engines on a 50:50 blend of jatropha oil and jet A-1 fuel. Subsequently, Air New Zealand and Houston based Continental Airlines have run tests in Jan. 2009, further demonstrating the viability of jatropha oil as a jet fuel, especially for low claudification point. Japan Air also plans test flights in Jan. 2009 as well.

 

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The residue of oil extraction (seed cake) can also be processed and used as biomass feedstock to power electricity plants or used as fertilizer (it contains nitrogen, phosphorous and potassium). Another possible use for seedcake is as potential feedstock in gasification plants; reported value for Gross Calorific Value (GCV) of 18 MJ/kg and humidity content of approx. 8% make Jatropha seedcake an interesting biomass feedstock for syngas production. The gas obtained, even though has a rather low caloric value (10-15 Mj/Nm3), can be used in turbines or Diesel engines for electricity production.
 

Benefits

•    High oil yield per hectare
Jatropha is able to produce up to 1,5 tons of oil per hectare. Seeds are rich in oil content (32-27%). The tree is able to grow in area of low rainfall regime (200 mm per year) and in degraded lands. In highly irrigated areas or rainy areas Jatropha grows with higher yield.

•    Quality of the oil
The oil obtained by crashing the seeds is excellent for energy production purposes. In fact, refined Jatropha oil can be used to run stationary diesel engines for energy production. Additionally, it could be used as raw material for high standard (EN 14214) Biodiesel production.

•    Easy establishment, relatively quick growth, hardy crop
It can be planted in marginal lands such as: along the canals, roads or railway tracks, on farmers’ field borders as a boundary fence or as live hedge. It is resistant in arid/semi-arid areas and even on alkaline soils. It is used to reclaim wastelands outside and inside forests.

•    Atmospheric carbon storage
Jatropha stores it in the woody tissues and assists for soil carbon building up.
Both Jatropha uses, as power production and biodiesel production, can represent a way to reduce GHG emissions and therefore eligible within the Clean Development Mechanism (CDM) of Kyoto:

    From one hectare of Jatr. plantation, it is possible to sequester 40 tons of CO2 due to land afforestation;

 

    One ton of biodiesel from Jatr. can avoid about 3 tons of CO2 emissions;

 

    One ton of Jatr. oil for power generation can avoid 4 tons of CO2 emissions;

 

    By firing one ton of Jatr. seedcake instead of coal for electricity production, it is possible to reduce about 35% of CO2 emissions.

•    Energy securing
but also to decrease Country’s fossil fuel dependency and economical sensitivity to its price volatility, helping to achieve a higher energy security and diversification of energy sources.

•    Easy intercropping with other cultivations

 

•    Easy seed harvesting

 

•    Long seeds storage
The Jatropha seed can be stored for about 6 months, during which significant changes are not detected; actually six month storage does not affect the seeds oil content.

•    Jatropha plants are short and the harvest season is before the rainy season

 

•    Not edible by humans and other animals

 

•    Jatropha does not compete with food crops and can be used as protection for cash crops

 

•    Readily growth from plant cutting or seeds up to 3 – 5 m of height

 

•    Not good as forage material for its toxicity

 

•    Highly pest and disease resistant

 

•    Medicinal value

 

•    Jatropha bark contains tannin and the plant is a potentially honey producer

 

•    Several Jatropha co-products’ applications

 

When referring to co-products the portions of biomass are:

 

   Coat from the seeds separation (about 45% w/w of the whole fruit);

 

   Seedcake from the oil extraction (about 35% w/w of the whole fruit);

 

   Filtration residuals (about 2% w/w of the whole fruit).

 

The most common use of above-mentioned biomass is as a fertilizer for its high NPK value.  Jatropha co-products can also be used, under specific condition, for power generation.

 

Other applications include:    

 

•    Power (heat and/or electricity) generation from biomass combustion

Careful attention to the particular (physical and chemical) characteristics of the biomass and to the combustion has pointed to the fluidized bed boiler as suitable solution, especially for the seedcake (seedcake heat value is about 17 MJ/kg with an oil content of about 10% w/w). Homogeneity, moisture level and ash content are the principal parameters that have to be kept under control.

 

•    Biomass gasification

This technology represents an interesting opportunity for power or syngas production (gas mixture that contains varying amounts of carbon monoxide and hydrogen). Again Fluidized bed appears to be the most suitable technology. It is key to note that there are many parameters that can affect the gas mixture quality and at present biomass gasification is not yet a commercial technology.

 

•    Biogas production

The anaerobic digestion of Jatropha co-products is a recent interesting application. Jatropha oil seedcake has biogas generation potential within a range of 220 - 250 l per kg of cake under mesophilic temperature range of anaerobic digestion (25 and 40 °C). The biogas methane content, derived from that biomass, has been found to range from 65-70 % against 55 % from cattle dung. The best dilution ratio is 1:4 (cake : water). The gas can be used as engine fuel for the energy production.

Limitations


The Jatropha also suffers from certain limiting factors to be kept in mind while dealing with the species. These are as follows:

•    Jatropha cannot be grown on waterlogged lands and slopes exceeding 30°.

•    The ideal climatic conditions for Jatropha can be summarized as annual rainfall not exceeding 600 mm in moderate climatic conditions, 1200 mm in hot climatic zones and soil pH less than 9. The atmospheric temperature should not fall below 5° C as the plants are sensitive to ground frost that may occur in winters.

•    Jatropha seeds possess toxicity.

•    The plant develops its toxicity after the 5-6 months therefore it is vulnerable to animals attacks until that moment.

•    Jatropha is also host to the fungus "frogeye" (Cercospera spp.), common in tobacco.

•    It was observed that when oils are stored, their Free Fatty Acid (FFA) as well as viscosity increased. The Jatropha oil behaves as other vegetable oils: their storability can last one year without significant FFA changes. Vegetables oils need to be kept in storage conditions that prevent undue degradation. Exposure to air and moisture must be minimized.

 

 

 

 

                  LAUGUAGE

 

 

- Jatropha Publications - Hohenheim University

- Molecolar Cloning and sequencing of acetyl CoA Carboxylase (ACCase) gene from Jatropha curcas - R.K.Kumar, J.Devendra, J.T.Sudhakar

- Jatropha Manual - Josè Angel Alfonso Bàrtoli - Gota Verde

- Jatropha nursey -  Josè Angel Alfonso Bàrtoli - Gota verde