Fish meal plant used for making low value fishes

1. DESIGN,LAYOUT AND MAINTENANCE OF FISH MEAL
PLANT
- MERCISHA M

2. PRINCIPAL
 The main steps of the process are cooking for coagulation of the
protein thereby liberating bound water and oil, separation by
pressing of the coagulate yielding a solid phase (press cake)
containing 60-80% of the oil-free dry matter (protein, bones), and
a liquid phase (press liquor) containing water and the rest of the
materials(oil, dissolved and suspended protein, vitamins and
minerals).

3. FISH MEAL PLANT LAYOUT

4. Design

5. SITE SELECTION
 The plant should be erected as close as possible to the source of supply
of the raw material in order to avoid delays in handling.
 The following factors should be taken into account.
 (1) Fishmeal manufacture – offensive odours and are best sited away
from the nearest town.
 (2) Effluents need to be disposed of without causing pollution problems.
 (3) Areas where other industries produce smoke, dust or odours which
could taint the fish should be avoided.

6. (4)The cost of erecting buildings – nature of the ground.
* Areas where expensive pilling would be needed should generally be
avoided.
* Areas of land prone to flooding should also be avoided.
(5) All-weather roads are needed.
* These reduce the dirt.
* Reduce the risk of being cut off in bad weather.
* Shipping by rail should be considered.
* Proximity to an airport is an obvious advantage. (perishable, high value
produces such as live lobster are to be shipped)

7. BUILDING
 Buildings must be big enough to avoid people and equipment being crowded.
 All buildings should have an internal height of 3-3.6 m.
 A higher ceiling would be difficult to clean and a lower one would restrict ventilation.
 Buildings must be well constructed and kept in good repair.
 All areas where the product will be handled must be kept separate from areas such as living
quarters, offices, or engineering facilities.
 Single storey buildings are preferable to multi-storey ones as they do not have a load-bearing
second floor, and the movement of raw materials and products is easier.
 Adequate drainage above ground floor level is an additional problem in multi-storey
buildings.
 Non-porous material should be used for all construction; wood is unsuitable for walls, floor,
or any other parts of the building.

8. VERMS AND PEST
 The possible entry of insects, birds, and vermin such as rats and mice, must be prevented at
the construction stage.
 There should be no trees, gardens, cultivated areas, etc - provide habitats for vermin and
insects. The buildings should be surrounded by an area of concrete or tarmac.
 Flies, which are notorious for carrying disease, should be excluded from the processing area.
 Devices which use ultraviolet light to attract flies appear to be ineffective in tropical areas. It is
therefore probably more effective to exclude the flies than to try to catch them.
 Domestic animals such as dogs, cats, chickens, ducks, etc. should be banned from the site
altogether. All these warm-blooded animals can carry pathogenic organisms.
 Water traps at the points where drainage channels pass through the walls to the outside
should prevent the entry of rats, mice and cockroaches

9. FLOOR
 All floors should be made of a hard wearing, non-porous, non-slip material.
 They should be washable and should slope evenly to the drains.
 Corrosion-, erosion-and abrasion-resistant floor coatings are made especially for food
processing premises.
 They often have thermal shock-proof properties as well, and some contain bactericides.
 Resin based flooring materials are now widely used for food processing premises.
 They provide a durable covering which is extremely resistant to attack by oil, grease, acids
and alkalis.
 They are laid in a liquid form which cures and sets in a very short time.
 Continuous layers without joints can therefore be completely water

10. WALL
 Waterproof, smooth surfaced and washable.
 Ceramic tiles are best but these can expensive.
 Corrosion-resistant metal – stainless steel (expensive) or aluminium is also good, especially in
areas where physical damage may be expected.
 The protection should extend for at least 2 m up the wall.
 If concrete is used, it should be painted with a high gloss, light coloured, non-toxic paint.
 Some modern paints tough, hard wearing surfaces.
 Many special wall coatings are now manufactured for use in food processing factories; they
are tough, easily cleaned, and may inhibit bacterial growth.

11. CEILING
 These should consist of a continuous, smooth, unbroken surface, painted with white, high
gloss, non-toxic paint, and should be easy to clean.
 Overhead pipework, ducting and exposed beams should be kept to a minimum.
 Flush light and ventilation fittings ate desirable.
 False ceilings could be used to hide pipework etc.
 However, the area between this ceiling and the roof could become infested with vermin.

12. VENTILATION
 Proper ventilation provides comfortable working conditions and reduces the formation of
condensation and the build-up of unpleasant odours.
 Air conditioning is not really needed and is expensive to install and operate in commercial
premises.
 Good ventilation, however, is essential.
 Exhaust fans can be very useful, but they must be fitted so as to exclude insects when they are
not running

13. CLEANING
 At the end of the day’s work, the production area will be littered
with particles of food, water, and general dust and dirt.
 In order to maintain product quality, the whole area must be
adequately cleaned and disinfected.
 If processing operations are continuous, a certain amount of time
must be allocated for cleaning.

14. FISH MEAL LAYOUT PROCESS
 Large fish are hashed (A) while smaller fish (for example, those
less than 40 cm long) are fed directly at a constant rate by the
feeding machine (B) to the indirect steam cooker (C). The
coagulated mass is pre-strained in a strainer conveyor (D), or in a
vibrating screen, before entering the twin screw press (E). The
products from the press (press cake and press liquor) are treated
as follows.

15.  The presscake is disintegrated in the tearing machine (wet mill)(F) to facilitate
mixing with stickwater concentrate (see below) and drying in an indirect
steam dryer or a direct flame dryer (G).
 The meal passes through a vibrating screen (H) furnished with a magnet to
remove extraneous matter like pieces of wood and metal (for example, fish
hooks) before entering the hammer mill (J).
 The ground meal is automatically weighed out in bags by the scales (K), the
bags are closed (e.g., by sewing) and conveyed to the store. The meal is
storing in bulk.

16. MACHINERIES
 Harsher
 Hopper
 Cooker
 Twin screw press
 Milling
 Packing and storage

17. HARSHER
 large fish have to be hashed into smaller pieces before being passed by the feeder into the cooker. This
is to ensure uniform processing and equal temperature in the cooked material. Also, the feeder ensures
a steady rate of presentation to the cooker. The picture illustrates one type of hasher often used. It
consists of a rotor with staggered knives and a frame with a row of stationary knives.


18. HOPPER
 The picture Illustrates an example of a feeder. It consists of a hopper from the bottom of which the raw
material is carried to the cooker by a screw conveyor. The conveyor’s speed may be adapted to the rate
of throughput desired by means of a stepless gear.

19. COOKER
 The cooker is designed as a cylinder having a steam heated jacket throughout and a steam heated rotor,
designed as a screw conveyor with hollow flights. The cooker is equipped with covers throughout for
inspection and cleaning and with a nozzle system for blowing direct steam into the mass. The cooker
may be provided with automatic temperature control equipment, automatic level control for raw
material feeding, discharge control equipment (which is required particularly for handling soft raw
material) and a trap for collecting heavy foreign matter like stones and scrap iron. Cookers like this are
generally available in sizes which can process from 16 t to 1 600 t of raw material per 24 h.

20. TWIN SCREW PRESS
 This picture Illustrates the principle of the twin screw press. Pressing is carried out in a press chamber
consisting of two hollow interlocked cylinders. The cylinder wall is made of heavily supported strainer
plates made from stainless steel. The two press screws have tapered shafts and the screw pitch varies so
that the pitch, and thus the flight distance, is greatest at the thin end of the shafts. The screws rotate in
opposite senses. The material is fed in at the end where the shafts are thinner, and is carried towards the
end where they are thicker. As can be seen, the space for the material gradually reduces and, to
compensate, liquid is pressed out through the strainer plates surrounding the screws.

21. MILLING
 Pictures shows an example of a mill specially designed for grinding dried fish meal. The rotor consists of
a central shaft to which a number of rotor plates are fastened perpendicular to the shaft. Between the
rotor plates, hammers are held in position by bolts so that the hammers are removable. Special grinding
plates are fixed inside the housing. At the lower part of the housing, there is a screen with round holes.
By rotation of the rotor the material is hit by the hammers and the grinding plates and forced through
the screens. The ground meal is cooled by air which is also used for transportation of the meal.

22. MAINTENANCE
 Well designed and constructed factories often deteriorate
rapidly due to lack of maintenance.
 It is impossible to maintain good standards of hygiene in a
factory with cracked floors, damaged walls and generally
broken down equipment.
 Every effort should therefore be made to maintain the
factory as near to its new conditions as possible.

23. Thank you