1. EQUIPMENT FOR DEHULLING JATROPHA SEEDS consists of feed hopper (1), feed regulator (2), feed spout (3), central shaft (4), impeller (5), striking surface (6), conical shape discharge chute (7), outlet (8), frame structure (9), electric motor (10), motor drive shaft (11), impeller assembly base plate (12), driving pulleys (13, 14), v-belt (15), screen grader and air classifier; wherein the said feed hopper (1) is fitted on the top of the machine having the slanting bottom part; wherein the impeller (5) is fitted inside the housing fixed on a rotating central shaft (4); wherein the said central shaft (4) is connected to the electric motor (10) through the pulleys (13, 14) and v- belt (15); wherein the fixed casing with trapezoidal shape is connected to a conical shape discharge chute (7) with an outlet (8) at the bottom; wherein impeller (5), discharge chute (7) and outlet (8) are all mounted on the frame structure (9).

2. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said feed hopper (1) consists of a feed spout (3) at its slanting bottom outlet and a feed regulator (2).

3. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said impeller (5) consists of two circular spinning discs separated by a set of six square vanes.

4. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said motor drive shaft (11) has pulley (13) connected at one end and impeller assembly base plate (12) at the other end.

5. METHOD OF DEHULLING JATROPHA SEED comprising steps of (a) feeding whole Jatropha seeds to the said feed hopper (1) through the feed regulator (2); (b) conveying the seed to impeller assembly through feed spout (3) connected at the bottom of the said feed hopper (1); (c) getting seeds thrown toward the striking surface (6) through the centrifugal force of fast rotating impeller (5); (d) optimizing speed of impeller and travel distance for the seed; (e) obtaining mixture of kernels, hulls and brokens from the bottom outlet (8) of the dehuller; (f) conveying dehulled seeds to the screen grader for separating larger and smaller fractions of dehulled seeds; (g) conveying the said separated fractions to the air classifier; (h) collecting separately lighter hulls and heavy kernels by moving air in vertical column in the said air classifier.

6. EQUIPMENT AND METHOD FOR DEHULLING JATROPHA SEEDS as substantially herein described with reference to the foregoing description and figures. Dated this on 13th August, 2010

FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)

1. TITLE OF THE INVENTION

EQUIPMENT AND METHOD FOR DEHULLING JATROPHA SEEDS
2. APPLICANT (S)

(a) NAME: ANAND AGRICLUTURAL UNIVERSITY
(b) NATIONALITY: an Indian
(c) ADDRESS: College of Food Processing Technology & Bioenergy,
Anand Agriculture University ,
Anand -388110
Gujarat. India

3. PREMABLE TO THE DESCRIPTION

PROVISIONAL

The following specification describes the invention.

þ COMPLETE

The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention:

Present invention particularly relates to the field of the post harvest operations involved in Jatropha seed processing such as fruit harvesting, drying, fruit decapsulation and seed dehulling after which the said Jatropha seed oil can be transesterified to obtain bio diesel, an environment friendly bio fuel.

Background of the invention:

There are many plant species, which bear seeds rich in oil. However, the non-edible oil bearing seeds such as Jatropha, Karanja, Neem, Mahuda, Rubber, etc can be the better feed stocks for producing the bio diesel. The Jatropha, locally known as Ratna jyot or Vilayati erandi is the most suitable source for India. The high-energy contents of the seeds of Jatropha, with 30-40 % fat and 20-25 % proteins make the crop excellent raw material for the production of bio diesel.

Jatropha is one of the important forest tree crops of the country and grows widely with minimal inputs. Jatropha can grow almost anywhere – even on gravelly, sandy and saline soils. It can thrive on the poorest stony soil and on all kinds of wasteland. As the animals do not browse the Jatropha plant, it is used as live fence or bio fence around the fields or on the roadsides. Climatically, Jatropha is found in the tropics as well as in subtropics and does well even in lower temperatures. Its water requirement is extremely low and can stand long periods of drought by shedding most of its leaves to reduce transpiration loss. Jatropha is also suitable for preventing soil erosion and shifting of sand dunes.

The Jatropha seed oil is rich in “Octane” which makes it suitable as fuel. The oil is suitable for manufacturing of paints, varnish, dyes, organic pesticides and cosmetic items. The deoiled cake can also be used as organic manure to improve soil fertility. The methyl ester of Jatropha, known as Bio diesel in trade, can be mixed in any proportion with petroleum diesel fuel and may also be used as a 100 % substitute of diesel.
Jatropha seed contains about 35-45 % hull/shell. The hull doesn’t contain oil and rather obstructs the oil extraction/expression from the kernel inside. Use of dehulled seed permits a more efficient extraction of oil, a higher capacity of presses, a minimal wear on high-pressure parts. Hence, it is necessary to dehull the Jatropha seeds appropriately before the oil is extracted. However, the post harvest handling of seed done manually is a tedious, time consuming and labor intensive method and has many other inherent disadvantages.

As there is no standardized oil extraction technology available for Jatropha seed, the traditional oil expellers are used in vague for production of oil from this crop. However, the average oil recovery in traditional oil expeller for the Jatropha seed is very low between 60-70 % only. The process losses in the form of residual oil content in the deoiled cake are also quite high. Drudgery during the peration is also an important factor, which accentuates the problem.

Therefore, there is an immediate need for technological improvement of the process of oil expelling from the Jatropha seed, so as to produce the maximum amount of quality oil with the minimum losses and at the lower cost. Moreover, according to present invention, dehulling before oil expression has many advantages such as better quality oil (lower wax content and improved color), decreased volume of product to defat and decreased wear of expression units.

Object of the invention:

The main objective of the invention is the commercial exploitation of the Jatropha seed as a natural, renewable and eco-friendly source of biodiesel.

The specific objectives are the development of efficient and easy to operate equipment and effective method of dehulling of Jatropha seeds for the production of biodiesel.
It is yet another object of the invention to evaluate the best performance of the dehuller machine by measuring its dehulling index at various impeller speeds.

Summary of the invention:

The present invention provides equipment and method for dehulling the Jatropha seeds such that maximum oil of superior quality can be extracted and bio diesel can be produced through transesterification process. The said dehuller mainly consists of feed hopper, impeller assembly, drive mechanism, impacting casing, discharge chute and supporting frame. The basic principle of centrifugal dehuller is the use of centrifugal force to obtain impact and shear force for seed dehulling. Due to impact at a certain angle and force, the hull splits and as the seed slides along stationery surface, due to shear force hulls get peeled. The mixture of undehulled seed, kernel, hull and brokens are obtained from the bottom of the dehuller. Further, the investigation on the effect of impeller speed on dehulling efficiency, head yield, broken percentage and dehulling index is also carried out in the invention.

Brief description of drawings:

Figure 1 is the processing chart of the dehuller machine equipment using new invention.
Figure 2 is detailed front view of Jatropha seed dehuller machine.
Figure 3 is top, side and assembled view of Jatropha seed dehuller.
Figure 4 shows the variation in dehulling efficiency, head yield, broken percentage and dehulling index as a function of impeller speeds through the graphs.

Detailed description of the invention:

Uncertain supply of petroleum products, their spiraling prices and rising levels of carbon dioxide have drawn global attention to the development and use of renewable energy resources to supplement or replace fossil fuels. One major achievement in this respect has been the use of some plant oils in mixture with diesel as IC engine fuel.
In present invention, for commercial exploitation of Jatropha (Jatropha Curcus) seed as a source of bio diesel, specific studies on post harvest processing of Jatropha seed are carried out and the technologies found necessary such as decapsulation of fruit, dehulling of seed, oil expelling technology and transesterification technology have been developed. Several physical and mechanical properties of Jatropha seed and kernel are carried out for design of appropriate dehulling technology for Jatropha seed. A centrifugal dehulling unit working on impacting theory is developed for dehulling Jatropha seed and the effects of various machine design and operating parameters as well as material characteristics on dehulling performance are studied. Best performance is studied in terms of dehulling index as a function of dehulling efficiency and broken percentage.

Figure 1 shows the processing chart of dehulling of Jatropha seeds using the invented equipment and method. It discloses that the ripened Jatropha fruits are kept for sun drying by making heap for 7-10 days. The dried fruits become hard and black. These fruits are decapsulated either through a machine or manually by placing them in thin layer on hard surface and moving a wooden board over while pressing them down so that splitting of fruit husk takes place and seeds come out. The seeds are separated from husk.

After completion of decapsulation, Jatropha seeds are fed to dehulling unit in which seeds are impacted on hard surface at very high velocity so that the seed coat splits and peels off. Then the dehulled seeds are separated by screen grader and air classifier into hull and kernels.

Figure 2 shows the front view of the Jatropha seed dehuller equipment invented. Considering the shape and the other fragile characteristics of the seed hull, a centrifugal type of dehuller is designed and developed in the present invention. The machine consists feed hopper (1), feed regulator (2), feed spout (3), central shaft (4), impeller (5), striking surface (6), conical shape discharge chute (7), outlet (8), frame structure (9), electric motor (10), motor drive shaft (11), impeller assembly base plate (12), driving pulleys (13, 14), v-belt (15), a screen grader and an air classifier.
A slanting feed hopper (1) made of mild steel is fitted on the top of the machine. The bottom part of the hopper is slanted for easy feeding without clogging type and a feed spout (3) is provided at the bottom of slanting hopper outlet, which regulates the feeding to the impeller (5). The impeller assembly consists of fast rotating impeller (5) inside a fixed housing. The impeller (5) consists of six square vanes (Figure 3 – top view). The impeller is fitted inside the housing fixed on a rotating central shaft (4). The said central shaft is connected with the help of belt (15) and pulleys (13, 14) to the electric motor. The fixed casing is a hard thick plate designed a s trapezoidal section to work as the striking surface and further connected to the conical shape discharge chute (7) with an outlet (8) at bottom. The impeller (5), discharge chute (7) and the outlet (8) of the dehuller machine are covered with protective frame structure (9). The whole assembly is mounted on a sturdy frame structure (9). Drive mechanism consists of an electric motor (10), a drive shaft (11) with a set of pulley (13) at one end and impeller assembly base plate (12) at the other end. The power and speed from the electric motor is transmitted through a V-belt pulley arrangement.

Figure 3 of the present invention shows the top side and assembled view of the Jatropha seed dehuller. Impeller (5) has two circular spinning discs separated by a set of vanes (Figure 3 – top view) through which seed moves outwards with very high velocity and get impacted on striking surface (6) of stationary housing.

The whole Jatropha seeds are fed to the hopper (1) of dehuller through a feed regulator (2). The feed spout (3) conveys the seed to the impeller assembly of the centrifugal dehuller. The basic principle of centrifugal dehuller is the use of centrifugal force to obtain impact and shear force for seed dehulling.

Due to impact at a certain pre-designed angle and with preset centrifugal force, the hull splits and as the seed slides along stationery/striking (6) surface, due to shear force hulls get peeled. From the bottom outlet (8) of the dehuller the mixture of kernel, hull and brokens are obtained. The dehulled seeds are conveyed to a multi-deck vibratory screen grader. Larger and smaller fractions of the dehulled seeds (hull + kernel) get physically separated. These fractions are conveyed further to an air classifier where the velocity of air is adjusted according to the type of the fractions handled. Air moves in a vertical column and strikes the dehulled material coming from the screen grader. Lighter hulls get lifted and collected separately. Kernels are heavy and are collected separately for use in oil expeller.

The method of dehulling of Jatropha seeds is also invented, wherein the different material and machine parameters of the dehulling equipment are optimized. The efficiency of the dehuller depends on the impeller speed, feed rate.

According to an embodiment of the invention, the effectiveness of the dehuller in terms of dehulling efficiency, head yield, broken percentage and dehulling index is evaluated at different impeller speeds. The machine is tested at various rpm of the impeller and the observations recorded as below in Table 1 and Figure 4. The performance of the machine is evaluated at 100 kg/h feed rate having moisture content of 3.62 % (w.b.).

Table 1: Performance testing of dehuller for Jatropha seeds
(Feed rate = 100 Kg/h, Seed M.C. = 3.62 % w.b.)
Impeller Dehulling Head Broken Dehulling
Speed Efficiency Yield Percentage Index
(rpm) (%) (%) (%)
1088 46.93 60.28 0.00 0.46
1400 96.12 58.72 7.54 0.88
1555 99.39 49.88 16.26 0.83
1866 94.11 23.97 55.86 0.41

As the impeller speed is increased, the dehulling efficiency of the seed increases as shown in Table-1 and corresponding Figure 4. However, simultaneously the percentage of seed breakage also increases. It is observed that increasing speed beyond certain rpm causes excessive seed breakage and also results in vibrations of the machine, which is not desirable. Thus to find best performance of the machine a dehulling index is evaluated. Dehulling index is a measure of combined effect of dehulling efficiency and broken percentage and calculated by the following equation.

Dehulling index = dehulling efficiency in fraction X (1- broken percentage in fraction)

The impeller speed of 1400 rpm gives the highest dehulling index (0.88) and hence, the machine should be operated at that speed.

While this invention has been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims.

We Claim:

1. EQUIPMENT FOR DEHULLING JATROPHA SEEDS consists of feed hopper (1), feed regulator (2), feed spout (3), central shaft (4), impeller (5), striking surface (6), conical shape discharge chute (7), outlet (8), frame structure (9), electric motor (10), motor drive shaft (11), impeller assembly base plate (12), driving pulleys (13, 14), v-belt (15), screen grader and air classifier;
wherein the said feed hopper (1) is fitted on the top of the machine having the slanting bottom part;
wherein the impeller (5) is fitted inside the housing fixed on a rotating central shaft (4);
wherein the said central shaft (4) is connected to the electric motor (10) through the pulleys (13, 14) and v- belt (15);
wherein the fixed casing with trapezoidal shape is connected to a conical shape discharge chute (7) with an outlet (8) at the bottom;
wherein impeller (5), discharge chute (7) and outlet (8) are all mounted on the frame structure (9).

2. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said feed hopper (1) consists of a feed spout (3) at its slanting bottom outlet and a feed regulator (2).

3. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said impeller (5) consists of two circular spinning discs separated by a set of six square vanes.

4. EQUIPMENT FOR DEHULLING JATROPHA SEEDS as claimed in claim 1, wherein the said motor drive shaft (11) has pulley (13) connected at one end and impeller assembly base plate (12) at the other end.

5. METHOD OF DEHULLING JATROPHA SEED comprising steps of
(a) feeding whole Jatropha seeds to the said feed hopper (1) through the feed regulator (2);
(b) conveying the seed to impeller assembly through feed spout (3) connected at the bottom of the said feed hopper (1);
(c) getting seeds thrown toward the striking surface (6) through the centrifugal force of fast rotating impeller (5);
(d) optimizing speed of impeller and travel distance for the seed;
(e) obtaining mixture of kernels, hulls and brokens from the bottom outlet (8) of the dehuller;
(f) conveying dehulled seeds to the screen grader for separating larger and smaller fractions of dehulled seeds;
(g) conveying the said separated fractions to the air classifier;
(h) collecting separately lighter hulls and heavy kernels by moving air in vertical column in the said air classifier.

6. EQUIPMENT AND METHOD FOR DEHULLING JATROPHA SEEDS as substantially herein described with reference to the foregoing description and figures.

Dated this on 13th August, 2010