aquaculture presentation

AQUACULTURE ENGINEERING

FLOW-THROUGH AND RACEWAY

DEFINITION Raceway Aquaculture systems are based upon a continuous water flowing through culture tanks or systems and generally used where a constant water source is available from either river estuaries, the ocean, or rivers and lakes.Raceways used for aquaculture are rectangular shaped tanks, chutes or earthen structures with a continuous source of flow-through water introduced at one of the short sides and exiting at the opposite end.

DEFINITION A raceway, also known as a flow-through system, is an artificial channel used in aquaculture to culture aquatic organisms.


COMMON FISH CULTUREDcommon carp (Cyprinus carpio) in INDONESIAIN FRESH WATERTrout in KOREACatfishTilapia


DESIGN AND CONSTRUCTION

WATER SUPPLYConventional Flow-Through Systems- In a conventional flow-through system the oxygen requirement of the fish is supplied by the inflow water. The water flow rate that is needed for proper oxygen supply of the fish usually is larger than is required for flushing the metabolic wastes. Thus, in a conventional flow-through system the water flow rate should be calculated on the basis of the oxygen requirement of the fish.

WATER SUPPLYIntensive Flow-Through Systems- intensive flow-through systems have been designed in order to increase the stocking density or to decrease the water flow. In these systems the oxygen requirement of the fish is met by oxygenation of the inflow water. When the water flow rate of an intensive flow-through system is calculated, the flow rate that is needed for the flushing of the metabolic wastes becomes the critical factor.

DESIGN AND CONSTRUCTION

Rectangular-shaped pondOne of the types which is being used by the Indonesian fish farmers is rectangular-shaped pond. The size of the pond depends on the area available but usually its dimensions varies between 2 to 4 meters wide and 5 to 15 meters long and with average depth of 1.5 meters.The bottom of the pond must be more elevated than the water inlet and outlet or monk. The depth varies between 1 to 1.5 meters at the water inlet and 1.5 to 1.8 meters at the water outlet or about 0.3 to 0.5 meters elevation difference.

LAYOUT AND DESIGN

Layout of rectangular-shaped units of running water ponds

LAYOUT AND DESIGN

Rectangular pond for running water carp culture in West Java, Indonesia with installed demand feeders

LAYOUT AND DESIGN

Construction of rectangular-shaped ponds

LAYOUT AND DESIGN

Triangular-shaped pond

LAYOUT AND DESIGN

Other type of triangular-shaped pond practiced in West Java, Indonesia for carp culture

Layout of triangular-shaped running water ponds

LAYOUT AND DESIGN

LAYOUT AND DESIGN

Construction of triangular-shaped ponds

Raceway-shaped pondIn general raceway-shaped pond are the same as rectangular-shaped ones, but the principal difference is that the width of the inlet and outlet is the same as the width of the pond in the raceway type. Water will freely flow through the pond. In one area several ponds may be constructed in parallel systemThe size of the pond depends on area available but these are usually around 2 to 4 meters in width by 5 to 15 meters in length with 1.0 to 1.5 meters water depth.

LAYOUT AND DESIGN

Layout of raceway-shaped running water ponds

LAYOUT AND DESIGN

LAYOUT AND DESIGN

Raceway-shaped ponds for carp culture used in Majalaya, Indonesia

LAYOUT AND DESIGN

Raceway pond culture constructed along irrigation canal by damming with concrete dike and installing screen as well as demand feeder as practiced in

Sukabumi, Indonesia

Another type of raceway type ponds

LAYOUT AND DESIGN

Oval-shaped pondThe size of this type of pond depends on the area and water flow available. It is important to have relatively rapid water flow. Concrete pond should be used to prevent erosion. Generally, the size of the pond should vary from 10 to 100 square meters measuring 2–5 meters in width and 5 to 10 meters in length. It is suggested that the ratio of width to length is one to two. Water depth should be between 1 to 2 meters and the pond bottom must be sloped from inlet to outlet so the pond can be totally drained when needed.

LAYOUT AND DESIGN

Layout of oval-shaped ponds

LAYOUT AND DESIGN

Carp culture in running water with oval-shaped ponds with fencing of wire to prevent of poaching as practiced in Sukabumi, Indonesia

LAYOUT AND DESIGN

Polyethelene drum as running water culture tankMinimal volume of drum used is 100 liters. The inlet of the drum can be made from PVC pipe of 1 inch diameter while the outlet can be made of two PVC pipes, one with one inch diameter and the other a larger pipe (2 inch diameter). The smaller inside pipe with 1-inch diameter is used as the outlet and to adjust the water level in the drum and the outer larger pipe is used as outflow adjustment from the bottom so that the bottom of the outer pipe must have perforations

LAYOUT AND DESIGN

Carp culture in polyethelene drums or plastic drums as practiced in Sukabumi, Indonesia

LAYOUT AND DESIGN

Layout of fish culture using polyethelene drum method

LAYOUT AND DESIGN

Simple method of fish culture in polyethelene drum system

Raceway culture for Freshwater Species

Two different types raceway: Raceway pondThe raceways for fry production have a culture depth of 30cm with a bottom slope of 1/100 or more, while those for production of marketable trout have a depth of 60cm with a similar bottom slope. The raceways for brood stocks is about 90cm in depth. The outlets of the raceways are screened to avoid of trout escape. The screen with larger mesh sizes are preferred within the size permits. The widths of the raceways are 1.5m for fry and 3m or less for growing trouts. The lengths of the raceway are 10 to 30m.

The raceway ponds set together for the trout culture


Two different types raceway: Concrete siloThe concrete silos used for trout vary from 2 to 10 m in diameter, depending on the trout sizes cultured. The concrete silos are constructed with bottom slopes of 5∼10% to remove solid waste before water is discharged. The water from inlets is designed to be a driving force to circulate the water in the silo, allowing the solid wastes removed through the outlet located in the center of the silo. The silos for seed production of trouts are small-sized (less than 1m in diameter) are often of FRP (fiberglass reinforced plastics).



The concrete silos normally used for the seed production/fry culture of trouts

System operation for trout aquaculture(1) Aerations In any case water qualities are never better than those of the incoming water, but dissolved oxygen may be increased by aeration using some aerating machines, including pumps, agitators, and blowers).


Aeration by pumping of the culture water in the trout raceways

Aeration by water agitators in the trout raceways.


(2) Removal of solid waste matters Accumulation of waste matters in the raceway bottom spoils water quality, therefore successful removal of the waster matters is essential. Removal of the waste matters is achieved by sucking the matters directly with the aid of pumping machine or it can be performed by increasing water flow in the raceways. Normally, water velocities over 7∼8cm/sec are found to be effective for the waste removal in our system. Lowered water level down to 30 cm in depth makes the removal more effective. The waste matters accumulated in the raceway bottom should be pumped out.


(3) Productivity Productivity of fish is strongly related with exchanging rate of the culture water. For rainbow trout, it amounts 1㎏ /year under water flowing rate of 1ℓ/min. However, the productivity increases up to 5kg/year under same water flowing rate in case that best management is offered. (4) Waste water treatment Waste water treatment is one of the crucial factors in the raceway operation. Because only 20∼30% of total phosphorus supplied to the culture system are absorbed by the culture fish, appropriate treatment of the waste water is required. Bad treatment of the waste water often results in outbreaks of red tide in the reservoirs or rivers, causing a significant social problems.

Aeration by compressors in the trout aquaculture raceways.

Raceway bottoms are regularly cleaned by total water drainage.


REFERENCES http://www.fao.org/docrep/x5744e/

x5744e0e.htm http://www.extension.org/pages/58770/

raceways#.VIU0Q2eTJ3s http://en.wikipedia.org/wiki/Raceway_

%28aquaculture%29 http://www.coloriteaerationtubing.com/

aquacult_pages/aquaculture_raceways.htm http://www.fao.org/docrep/field/003/ac415e/

AC415E00.HTM

http://barrablue.com/support-services/detail/raceway-flow-thru-systems-58.html

http://www.lib.noaa.gov/retiredsites/korea/korean_aquaculture/raceway.htm

http://www.paddlefishfarming.com/in-pondracewaysystem.html

http://en.wikipilipinas.org/index.php/Plywood_Aquaculture_Tank

http://www.fao.org/docrep/field/003/ac415e/AC415E00.HTM

REFERENCES

aquaculture presentation

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