DEVELOPMENT OF FISH PELLETING MACHINE

Davies, R.M

1. Department of Agricultural and Environmental

Engineering, Niger Delta University, Wilberforce Island.

Bayelsa State.

+Correspondence: rotimidavies@yahoo.com

1

INTRODUCTION

Pelleting has been a popular processing technique in feed manufacturing industries. In

basic terms, pelleting converts a finely ground blends of ingredients into dense, free

flowing agglomerates (pellet). Pelleting operations are not without cost. It is expensive

process in terms of capital and variable cost, but the expense is usually justified in

improved plant profit as well as animal growth performance. To this end, a pelleting

machine could be described as a device for injecting particulate, granular or pasty feed

into holes of a roller/die, and then compacting the feed into a continuous solid rod to be

cut-off by a knife at the periphery of the roller/die(Steven, 1985) and (Arora, 2007).

The flat die pellating machine is still in use in certain applications, the ring die pellet mill

quickly became the preferred design and consequently adopted by the animal feed

industry and has remained the form of pelleting machine of choice today. In addition to

the ring die pellet mill, auxiliary equipment have been developed including, conditioners,

coolers, dryers, and related processing equipment (Ombu, 2008).

According Koh (2007) reported that the art of pelleting can be best described as a

complex set of process that converts the finely ground blend of ingredients into dense,

free flowing pellets. The formation of the pellets actually occurs at the nip between the

screw anger conveyor (roll for ring-die pellet mills) and the die. The pelleting process

involves: injection of feed into the holes of the roller, crumbling of the feed and steam

cooking, feed compaction, shaping into a continuous rod with the help of dies cutting of

pellets and pellet sieving.

One of the major problems encountered with the manufacturing of pelleted aquaculture

feeds especially in developing countries is that, aquaculture feeds are invariably produced

within feed mills specifically designed and geared towards the manufacture of poultry

and livestock feeds. And as such, do not have necessary capacity for fine grinding nor the

material put through, to justify the purchase of such equipments. Needless to say the cost

of fine grinding both in terms of equipment procurement and energy consumption is high

(Vernier, 1988).

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The choice of pelleting technique to be employed will depend on the feeding habit of the

fish to be fed and its physical requirements (such as, feed size, buoyancy, texture,

palatability and desired water stability) for all stages of the culture cycle. The technical

factors will in turn have to be balanced against the market value of the cultured species

(Hasting and Higgs, 2004) . Thus, the decision to make a certain kind of pellet must be

based on knowledge of the animals’ biology, physiology and behaviour and also, the

nature of culture system being used.

A holistic review of fish pelleting machines revealed that only a handful of pelleters are

available for the fish industry world wide as compared to other animal pelleters. This is

as a result of the limited number of industries involved in the manufacture of fish feed

equipment. In fact, one will not be wrong to attribute this to the popular perception that

aquaculture is a high risk activity hence, the poor participation in this highly lucrative

industry (Vernier, 1988) and (Koh, 2007).

In Nigeria, the need for pelleting machines have been made and the fish feed industry has

been described as poorly developed while its demand remains high. More so, where

aquaculture is been practiced at a commercial scale, feed used is either imported totally

or partially to complement the domestic supply. Denmark and the Netherlands are the

suppliers of a good percentage of the feed used in Nigeria.

Further more, in modern aquaculture, feed generally accounts for more than half the

operating costs and whereby feed is imported, its share of the production cost can even be

more important curb the problem of feed wastage by producing different pellet sizes for

different levels of development of the fish (Rolf, 2007).

1. Recent developments have shown that various feeds are pelleted using different

techniques which are deemed appropriate by the food Scientist or nutritionist

(Rolf, 2007). The techniques reviewed in this work piece are: steam-conditioning

pelleting technique, extrusion technique, dravo’s non-compacting technique and

the cold pelleting technique.

3

In the late 1930’s, some processors began to subject their pellet-forming mixtures of

animal feed to steam-conditioning pellating technique by passing the mixtures through a

conditioner prior to introduction into the extruder. The addition of steam according to the

processors, improves production rates, reduces die wear, and improved pellet quality.

Thus, the steam-conditioning was quickly adopted by the industry and has remained an

integral part of the pelleting process till date.

The conditioning involves the injection of steam into the feed mash as it is conveyed

through the conditioner which generally consists of a cylindrical tube with a rotating

shaft upon which numerous paddles or picks are mounted. The conditioning steam

increases the temperature and moisture content of the mash. The moisture content

provides lubrication for compression and extrusion, and in the presence of heat causes

some gelatinisation of raw starch present on the surface of the vegetative ingredients,

resulting in adhesion (Mac Bain, 1966).

One of the recent developments in the design of pelleting systems is the pressure

pelleting system. The pressure pelleting system is one in which the steam-conditioner and

the pelleting die cavities are pressurized. This allows the use of high temperatures and

longer conditioning times to improve pellet durability and increase production rate.

However, the use of increased temperatures and steam-conditioning militates against the

inclusion heat sensitive and labile ingredients which are desirable in complete feeds

Ombu, (2008) developed a method of producing ready to consume animal feed pellets

without using steam and elevated temperatures. They premixed solid and liquid

ingredients of the feed except for the liquid binder ingredient which is mixed. After

mixing, the mash was delivered to the pellet mill feeder through a bypass of the surge bin

above the pellet mill. The mash was fed into the pellet mill conditioning chamber and

then to the roller and die extruder. Steam was not added and no mash conditioning was

involved. When the mash was compacted through the die, soft moist pellets were formed.

Before the design and fabrication of the pelleting machine, it is necessary to consider

some physical and engineering properties of the feed marsh to be pelleted. These include

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moisture content, bulk density, size, angle of repose and feed formula. These properties

are greatly inter-dependent (ASAE 2003).

One of the primary objectives of all commercial feed manufacturers is to economically produce

the best quality pellet possible (Hasting and Higgs 2004). This is not only important from a

customer satisfaction point of view, but it is becoming evident that animal growth performance

can be affected by poor quality of feed pellets. This design work is therefore carried out to

develop a manually operated pelleting machine for fish feed.

2.0 MATERIALS AND METHODS

2.1 DESIGN DEVELOPMENT

There is need for the development of fish feed pelleting machines for our local based fish

farmers and feed manufacturing industry in Nigeria. For agricultural mechanisation to

succeed in Nigeria it must be based on indigenous design, relatively affordable, simple in

operation and less energy consuming (Igbeka et al; 1992; Jekayinfa, 1995; Jekayinfa, et

al, 2003; Odigboh, 1999 and 1997). The main features of the machine are: hopper,

extrusion barrel, screw auger, bearing housing, flat die, pulley, sprout (gravity chute)

knife cutter and the supporting frame.

2.2 THEORETICAL BACKGROUND

The background theory is a modification of the continuity equation based on the principle

of conservation of mass.

Mathematically, the principle is thus applied:

5

(1)

But, (2)

(3)

Where , = density of feed and pellet respectively

= volume of feed fed into the extrusion barrel

= volume of pellets extruded through the flat die

Also, the volume of feed in the hopper will be distributed through the compacting

chamber per unit time at a distance of

………………………………………………….………(4) (3

Where Speed of the auger in r/min

Radius of the distributing chamber

Thus, the cross-sectional area of the cylindrical housing Ac is

……………………… (5)

Where is the diameter of the chamber

6

The total volume of the feed that will be distributed from the hopper through the

housing, VF is

…………………………………………………….………..(6)

…………………………………………………….………(7)

Similarly, let the number of holes in the die be n

The area of opening of the die, Ao is

………(7).

Where area of a hole, with diameter

……………………………………. (8)

Supposing that the cutter cuts number of pellets of length lx from a hole in the die at the

end of a pelleting operation, the overall length of pellets extruded given as is

7

………………………………………………….…………… (9)

Thus the total volume of pellets extruded is

………………….……………… (10a)

…………………………………………………….… (10b)

Hence, substituting equations (6) and (10b) into equation (3), I have

…………………….……………….…… (11)

……………………………………………….. (12)

Let …………………………………………………………………. (13)

Where k is the compaction ratio

8

…………………………………………………………… (14)

ASSUMPTIONS

As most mathematical analysis of a real system have some assumptions built into them,

the following assumptions are made in the analysis of this current design.

1. All materials fed were pelleted.

2. No material was left stagnant due to change in cross-sectional area of flow.

3. The mass of air in the feed mash is negligible.

4. The clearance between the auger and the cylindrical housing is also negligible.

5. The formulated feed for pelleting is homogenous.

6. The force of adhesion between the feed marshes is greater than the force of cohesion

between the feed particles and machine surfaces.

2.3 Design calculation

The pelleter shall be made up of a helicoidal-flight screw conveyor fit into a pipe

(extrusion barrel) with minimum clearance, a flat die extruder and a knife cutter.

2.3.1 Screw auger design:- The screw conveyor is of the helicoidal flight type desired to

convey the feed marsh at a rate of 1500kg/hr (0.417kg/s).

The diameter of the auger is computed using the formula,

(Kurmi and Gupta 2007)………………………………… (15)

Where = capacity of the auger (kg/s)

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= loading factor (taken as 0.55 to allow for space occupied by

the helix and shaft

= diameter of auger (m)

n = speed of the auger (rps); 5 to 7 rps

b = bulk density of the feed = 320kg/m3

Rearranging equation 15,

……………………………………………………………(16)

= 0.084m = 84mm use 100mm (4’’ Auger)

For the auger to efficiently collect materials from the intake chute (hopper), convey and

generate enough pressure to extrude the materials through the die, a minimum length of

600mm is considered for this design.

Hence, the power required to drive this auger is computed as thus:

Power, P ……………………………………………………………… (17)

Where tangent of angle of repose of the feed

L = length of the screw conveyor (m)

e = efficiency

10

g = acceleration due to gravity (m/s2)

The theoretical power is multiplied by “3” to allow for friction of the helix, bearing

friction, back pressure of the feed conveyed on the helix, etc. An efficiency of 0.75 is

used to compensate for power losses along the drive mechanism.

Therefore, the power, P =

= 11.56W

An additional power of 150W is added to balance the resisting force induced by the die.

Hence, the total power needed to drive the screw auger is

P = 11.56 + 150 = 161.56W

0.162kW = 0.217hp

2.3.2 Flat die design/specification:-

An effective open area of 55% shall be considered in this design. This is to ensure

efficient extrusion and performance of the entire equipment been designed and more

importantly, an increase in bulk density is induced on the final pellets. With this

percentage of effective open area, the die will be able to withstand more compressive

stresses and hence, lasts longer.

To this end, the number of holes to be impressed on a die can be calculated as follows:

Effective are of opening,

11

……………………………………….. (18)

Rearranging the equation,

………………………………………. . (19)

Substituting for Ac and Ah from equations (3.5) and (3.8),

…………………………………… 3.20

The on the 3mm, 4mm, 6mm, 8mm and 10mm Dies are tabulated below (extrusion

barrel-100mm dia.; ¾’’ shaft).

S/N Diameter of Hole Number of

Holes

Die thickness

1 3mm 344 3mm

2 4mm 193 4mm

3 6mm 86 6mm

4 8mm 48 8mm

5 10mm 31 8mm

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Table 1: Die specifications

2.3.3 HOPPER DESIGN:- The hopper shall be the wide open type with two different

segments. The first is a truncated rectangular pyramid and the second, a rectangular box.

Consider the figure below

Fig. 2.2 hopper geometry

Hence, the volume of the hopper is a combination of the volume of the rectangular

truncated pyramid and the rectangular box.

For the rectangular truncated pyramid,

Fig. 2.3 Hopper geometry - truncated rectangular pyramid

Consider a small element of height dx of the hopper at a distance x from the top. From

the goemetry of the figure, the width of the hopper at x from the top can be

computed as thus:

13

……………………………………………………… (21)

⇒ ……………………………………… (22)

Similarly, the breadth is derived as follows:

………………………………………………..………(23)

⇒ ……………………………….……… (24)

The cross-setional area of the hopper at this section is

…………………….. (25)

And the volume at this section with height dx is

………………………………………. (26)

………. (27)

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Thus, the total volume of the truncated rectangular pyramid can be obtained by

integrating equation (27) from 0 to h.

………………………… (28)

On the other hand, the rectangular box with height h1 is computed as

Fig. 2.4 Hopper geometry - rectangular

follows:

Area = …………………………………………………………………… (29)

Volume, VR = ……………………………………………….……… (30)

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Therefore, the total volume of the hopper can be expreesed as:

V = ………………… (31)

Choosing

The volume of the hopper is thus

V = 0.00884M3

2.3.4 SPOUT DESIGN

This is a gravity chute from which the extruded pellets are discharged.

MANUAL HAND CRANK LEVER

Fig 2.5 Design diagram of crank

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The end of the shaft shall be threaded internally to receive a corresponding external

thread as in the case of nuts and bolts. The length (L) shall be 200 to 300mm. The lever is

thus designed as follows:

Diameter of the handle (d); this is obtained from bending considerations. Assuming the

effort (P) applied to the handle acts at 2/3 of its length (L), then the maximum bending

moment, M is computed using

……………………………………………………… (32)

But the section modules ……………………….……….... (33)

Therefore, the resisting moment is

…………………………………………………………. (34)

The permissible bending stress for the material of the

handle.

Thus, equating the resisting moment to the bending moment, I have

……………………………………………… (35)

…………………………………………………………….. (36)

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Diameter of threading (D); since the bolt will be subjected to twisting moment and

bending moments, its diameter would be obtained from equivalent twisting moment. The

twisting moment (T) on the external threading of the shaft is

T = P x L……………………………………………………………….… (37)

And the bending moment (M) on the journal of the shaft is

……………………………………………………… (38)

Where x is the distance from the end of bolt to the centre of the threading.

The equivalent twisting moment, Te is

Te = ……………………………………………………………… (39)

Te

Te = ……………………………………….……………. (40)

But the equivalent twisting moment, Te is also

Te = …………………………………………………..…… . (41)

⇒ Te = …………………………………. (42)

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D3 = …………………………………………………… (43)

Where is the induced shear stress in the lever caused by the twisting moment, T =2/3P

x L.

The value of can be obtained by checking the above twisting moment with

T = d3 = 2/3P x l

⇒ /3 d3

32Pl/ 3 …………………………………………………….……… (44)

Hence, the maximum principal or shear stress induced can be obtained as follows;

Max. Principal stress,

m (max) = 1/2[ + ]……………………………..………..……… (45)

And Maximum shear stress

…………………………………………………..… … (46)

2.3.5 DESIGN TORQUE

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From section 2.4.1.1, the power transmitted by the shaft is 0.162kW. The mean torque

transmitted by the shaft can be deduced from the relation:

…………………………………………………………………………..(47)

But ………………………………………………………(48)

………………………………………………………………….

……….. (49)

=

Assuming the maximum torque is not to exceed the mean torque by 50%, the design

allowable torque, Td will become

2.3.6 DESIGN OF THE CENTRAL SHAFT

For the purposes of this design, the shaft is modelled as a simply supported cantilever

beam as shown below. With the pulley keyed to the shaft, the angle of wrap of belt on

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pulley is 1800 and the belt tension acts vertically downwards. The ratio of belt tensions =

2.5.

fig 2.6 Machine design diagram

The shaft is made of steel having ultimate tensile stress and yield stress of 400Mpa and

240Mpa respectively. Using the ASME code to design the diameter of the shaft with

combined fatigue and shock factors in bending and torsion as 1.5 and 1.25 respectively,

the permissible shear stress ……………….. (50)

or

……………………………………………….. (51)

Any of the above two equations are minimum;

Or

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Torque Transmitted:

Since the torque is transmitted by a belt drive:

Torque, Td = ………………………………………………………. (52)

…………………………………………………… (53)

Also, …………………………………………………………….……

(54)

Reaction at the Bearings:

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Fig 2.7 Free-body diagram of shaft

……………….... (55)

⇒ and

)

Maximum Bending Moment Calculations:

23

B.M at E = 0

B.M at D

B.M at C =

B.M at B =

B.M at A =

24

Fig 2.8 Force and Bending Moment Diagrams

Finally, the diameter of the shaft now be computed using the formula

…………………(56)

25

Hence, use 20mm shaft

2.4 CONSTRUCTION, TESTING AND PERFORMANCE EVALUATION

2.4.1 Fabrication

The main features of the machine are: hopper, extrusion barrel, screw auger, bearing

housing, flat die, pulley, sprout (gravity chute) knife cutter and the supporting frame.

These components are fabricated as discussed below:

2.4.2 Feeding hopper:

The hopper is to be constructed using a 14 gauge galvanized steel sheet. The hopper is in

form of a rectangular based truncated pyramid with top length of 375mm, bottom length

of 200mm and height of 100mm.The edge of the top is reinforced with a 12mm diameter

reinforcement bar.

2.4.3 Screw auger: The central membrane is to be fabricated from a 1.5mm flat steel plate

turned to close bearings tolerance of 5mm maximum round the interior of the extrusion

barrel on the outer part and welded to the central shaft on the inner part.

Bearing housing: This is to be fabricated with a 10mm thick plate. At the central, a

70mm diameter x 30mm mild steel plate will be welded to the plate and turned to form

the bearing housing. The flange is in turn welded to the barrel.

Extrusion barrel: This is to be made with a galvanized mild steel pipe with one of its

sides closed to form the bearing housing and the other side to be flange with 3 Nos, 8mm

hole bolt carriers to which the die, knife cutter carrier and spout is to bolted. On either

side of the barrel is to be welded a 3’ x 2’ U- pipe to form the base of the barrel.

2.4.4 Supporting frame:

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The stand (frame) will be fabricated with 2’ x 3’ U- tube pipe with provision for

extrusion barrel mounting. A further provision will be made for a second bearing. This

bearing carrier shall be mounted 300 with the vertical supports at the centre of the base

frame and a vertical welded to it at a distance of 150mm from the first bearing coupled to

the extrusion barrel. See drawings for more details.

Assemblage

The machine shall be assembled as shown in appendix 1A-1C.

Table 2: Feed formulation to use for fish pelleting machine performance evaluation test.

S/N FEED INGREDIENTS PERCENTAGE COMPOSITION

BY MASS (%)

1 Maize 27.6

2 Palm Kernel Cake (PKC) 14.5

3 Fish Meal 8.2

4 Soybean Meal 44.2

5 Fat/Oil 0.5

6 Vitamin Premix 2.5

7 Binder 2.5

8 Water Varied

2.4.5 Performance evaluation

The portion of damage pellet was separated from the entire extruded pellets and weighed.

The following formulae were used to computing different parameters:

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1. Pelleting efficiency, (%): This is defined as the ratio of the quantity of

feed pelleted to the total quantity of feed marsh used in the sample.

= ………………………………………… (57)

2. Mechanical (visible) damage, MD (%): This is the ratio of the quantity of broken

pellets in the extruded product to the total feed

MD ……………………………… (58)

3. Feed loss, FL (%): This is the ratio of the quantity of unpelleted feed to the

total feed sample.

…………………………………………

…….(59)

Where MF = weight feed fed into the machine (kg)

MPF = weight of pelleted feed (kg)

MWP = weight of whole (undamaged) pellets (kg).

Results and Discussion

The performance of the dual pelleting machine was satisfactorily. The machine was

designed to be powered either manually through hand crank lever or mechanically

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through prime mover. The operation of the machine completely eliminates the drudgery

involved in hand moulding fish feed. The prime mover generated power that was

transmitted through belt to the pellating unit and producing sufficient torque unit. A 5hp,

1100-1440rpm electric motor was chosen. But for the purpose of performance evaluation

the machine was powered manually through crank lever. Table 1 shows the summary of

performance evaluation of the pelleting machine. Cursory look at the table revealed

pelleting efficiency for the three different sizes of dies ranges from 83.3-93.3% while the

percentage of mechanical damage ranges from 20.4 - 44.9% and the percentage feed loss

ranges from 2.57 – 2.80%. Fig.1 shows the variation of pelleting efficiency with

moisture content. It was observed that the higher the moisture content of the feed marsh

the lower the pelleting efficiency for the three different sizes of die. Fig. 2 shows the

percentage feed loss with feed moisture content. It can be seen the higher the moisture

content the lower the feed loss for three different dices. Fig.3 revealed the percentage

mechanical damage with moisture content. The mechanical damage increases with

increase in moisture content. The pelleting efficiency and feed loss decreases with an

increase in the moisture content of the formulated feed marsh while mechanical damage

increased. Tachometer was utilised to measure the auger speed. The rate of pelleting was

observed to increase with auger speed. Mechanical damage was also seen to increase with

speed while feed loss on the other hand, decreased with speed. The rate of production

was observed to increase with die size while feed loss and mechanical damage decreased

with die size at the same feed moisture content and speed.

Table 3: Input and output test parameter for 4mm, 6mm and 8mm die for same feed.

DIE

SIZES

Test Trails Mass of feed

load (kg)

Amount of Water

( volumetric)

Mass of Feed

pelleted

(kg)

Mass of whole

pellets (kg)

4mm

1 3 1 2.71 1.63

2 3 2 2.65 1.46

3 3 3 2.57 1.29

6mm

1 3 1 2.72 1.91

3 3 3 2.66 1.76

29

8mm

1 3 1 2.80 2.24

2 3 2 2.76 2.15

3 3 3 2.71 2.01

T

able 3: Summary of performance evaluation of pelleting machine.

DIE

SIZES

Test

Trails

Amount of Water

( volumetric)

Pelleting

Efficiency (%)

Mechanical

Damage (%)

Feed

Loss

(%)

4mm

1 1 90.3 39.9 2.71

2 2 88.3 44.9 2.65

3 3 85.7 49.8 2.57

6mm

1 1 90.6 29.8 2.72

2 2 89.3 32.1 2.68

3 3 88.7 33.8 2.66

8mm

1 1 93.3 20.4 2.80

2 2 92.0 20.7 2.76

3 3 90.3 25.8 2.71

30

Fig.1 Pelleting Efficiency Vs Feed Moisture

31

8mm Die

6mm Die

4mm Die

32

Fig.2 Percentage Feed Loss Vs Feed Moisture

33

4mm Die

6mm Die

8mm Die

Fig 3 Mechanical Damage Vs Feed Moisture

34

4mm Die

6mm Die

8mm Die

CONCLUSION

A fish pelleting machine capable of being hand-driven and electric motor or gasoline

engine driven has been designed, fabricated and tested. The cost of procurement of the

pelleting machine is quite affordable to both individual local farmers and co-operative

farmers. The operation of the machine does not require any highly technical expertise.

More so, for farmers who can not afford a gasoline engine or electric motor to power the

machine can also manually operate the machine to produce pellets to feed their stock.

Furthermore, different sizes of pellets can be produced with the machine as the design

also takes into account the ease with which dies can be interchanged.

The following conclusions are made from the work piece:

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1. The pelleting efficiency and feed loss decreases with a increase in the

moisture content of the formulated feed marsh while mechanical damage

increased.

2. Although not quantitatively measured, the rate of pelleting was observed to

increase with auger speed.

3. Mechanical damage was also seen to increase with speed while feed loss on

the other hand, decreased with speed.

4. The rate of production was observed to increase with die size while feed loss

and mechanical damage decreased with die size at the same feed moisture

content and speed.

RECOMMENDATION

To this end, local farmers, Local Government Administrators, State Government and

indeed, the Federal government can take advantage of the technology offered by this

machine to increase fish production and ease the drudgery and cost associated with

the importation of fish feeds will automatically reduced.

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REFERENCES

1. ASAE, 2003, ASAE Standard: ASAE S 269.3, Wafers Crumbles, and Crumbles

– Definitions and Methods for Determining Density, Durability, and Moisture

Content, ASAE Standards 2003, The Society of Engineering in Agriculture, St.

Joseph, Michigan: 70-72.

2. Igbeka, J. C, Jony, M. and D. Griffon (1992). Selective mechanisation for cassava

processing. J. Agric, Mechanisation. In Asia, Africa and Latin America, 23(1):

45_50

3. Jekayinfa. S. O. 1995. Some Engineering Aspects of Cyanide Removal in cassava

processing. M. Sc Seminar Report. Department of Agricultural Engineering,

University of Ibadan.

4. Jekayinfa, S. O. Olafimihan, E. O and odewole, G. A 2003. Evaluation of a Pedal

_ operated cassava grater. LAUTECH Journal of Engineering and Technology 1

(1). 82_86’

5. Koh H.M. 2007 Aquatic Feed pelleting techniques: part1, (2007, September /

October _ last update). [Online] Available: www.efeedlink.com/showdetail/?id=

%.

6. MacBain, R., 1966. Pelleting Animal Feed, American Feed Manufacturers

Association, Arlington, Virgin.

7. Odigboh, E. U. (1997). Confronting the challenges of Agricultural Mechanization

in Nigeria in the Next Decade: Some Notes, some options. Keynote Address

Presented at the Nigerian Society of Agricultural Engineers (NSAE)’s Annual

conference NSAE Conference Proceedings Pp. 7_16.

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8. Odigboh, E. U. 1999. Engineering Design for strategic supply of Appropriate

Farm Rural Machines/ Equipments for Enhanced Agricultural Development in

Nigeria. Paper presented at First National Engineering Design Conference,

organised by NEDDC of NASENI, COREN and NSE, Abuja, Sheraton Hotels

and Towers, September 29 _ 29.

Ombu, E.P 2008. Design fabrication and Testing of a fish pelleting machine.B.Sc.

project. Department of agricultural and Environmental Engineering, Niger Delta

University, Wilberforce Island, Bayelsa State, Nigeria.

9. Arora, R.S.2007 Academic’s Dictionary of Mechanical Engineering, 1st Ed,

Academic (INDIA) publishers, New Delhi.

10. Kurmi, R.S. and Gupta J.K. 2007 A Textbook of Machine Design, 14st Ed,

Eurasia Publishing House (PVT.) LTD, New Delhi.

11. Rolf J. K. Ring Die pellet mills: FBA 15 (2007, July/August _ last update).

[Online] Available: http://www.efeedlink.com/showdetail/?id

Jekayinfa S.O 2005. Development of a Grain screw Dispensing Machine, J, NIAE,

27, 177_181

Stevens, C.A., 1987, Starch Gelatinization and the Influence of Particle Size, Steam

Pressure and Die Speed on the Pelleting Process, Ph.d Dissertation, Kansas State

University, Manhattan, Kansas.

12. Verner, W.A. 1988. Best Cost vs. Least Cost, Feed Management, Vol. 39, No. 4,

Watt Publishing Company, Mount Morris, Illinois: 36, 58.

13. Hasting W.H and Higgs, D 2004.Feed milling processes,

www.freepatentsonline.com/807243.html

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APPENDIX 2

S/No Items Materials Quantity Amount

(N)

1 Feeding

hopper

Mild steel plate gauge 14 4ft x3ft 4.500.00

2 Extrusion

barrel

Galvanized mild steel pipe 100mm x

600mm

8,000.00

48

3 Screw auger Steel fabricated 1 No 12,000.00

4 Bearing

housing

Mild steel fabricated 2 No 4,000.00

5 Bearings 6205 2 No 1,800.00

6 Pulley

(v-grove

1No 4,500.00

7 V-belt Rubber (heat heated) 1No 600.00

8 Spend Mild steel plate gauge 4ft x3ft 4,500.00

9 Flat die Mild steel fabricated 2ft x 2ft 8,200.00

10 Rotary knife Mild steel fabricated 1 No 600.00

11 Stand Fabricated iron u-pipe 1 length 5,500.00

12 Bolt nut

washer

Mild steel 4 Nos 300.00

13 Screw Cast iron 1 No 30.00

14 Shaft Cast iron 1 length 7,500.00

15 Miscellane-ous 20,000.00

TOTAL

78,880.00

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APPENDIX 3

Photograph of fabricated duo fish feed pelleting machine.

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Project student (right) & other Pelleting machine

Colleagues under construction

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