project report presentation1
TRANSCRIPT
PROJECT REPORT PRESENTATION
TOPIC:A RECIRCULATING AQUACULTURE SYSTEM
PRESENTED BY:
ANDREW O. AYUKA
F21/1711/2010
SUPERVISOR: DR. OMUTO C. THINE
INTRODUCTION• Re-circulating aquaculture systems
are indoor, tank-based systems in which fish are grown at high density under controlled
environmental conditions.
•These systems can be used where suitable land or water is limited, or where
environmental conditions are not ideal for the species being cultured.
•This type of aquaculture production system can also be practiced in marine
environments
PROBLEM STATEMENT AND PROBLEM ANALYSIS
A tremendous increase in the Kenyan population with a direct proportion in demand for protein-rich food.
The higher cost of protein-rich food in the country due to higher demand and limited supply
High pollution in ponds, rivers and lakes
High concentration of ammonia causes lethal stress to fish
OBJECTIVES
OVERALL OBJECTIVE
To design a re-circulating aquaculture system.
SPECIFIC OBJECTIVES
To apply principles of design of fish pond aerators in a re-circulating aquaculture systems
design of RAS components
Statement of scope
The scope of the project is limited to engineering design and functions of aquaculture system
The design can also be done for both marine and fresh water
Site Analysis and Inventory Site location and description is very subjective and has not been
determined yet. The project however targets urban areas where land and ground water are limited like Nairobi County and its neighbouring counties which have been studied to have the highest population in the country and readily available market for fish products.
Major issues that must be considered during the site selection process are:
location of the site
environmental sensitivity of the site
climatic factors
access to water
quality of water supply and
available options for effluent disposal.
Literature Review
Development of RAS started in the 1950s in Japan and was later introduced in Europe in the 1970s. Its commercial utilization was also introduced Netherlands, Denmark and Germany and Egypt in 1980s.
Aquaculture in Kenya is a new technology striving to satisfy a growing market for protein-rich food (fish) and reduce poverty in rural areas.
RAS has not yet been fully embraced compared to other countries and this has been attributed to the lack of the awareness by the citizens, lack of necessary skills and lack of sufficient or reliable fish feed just but to mention a few
Why recirculate? Conserves water Permits high stocking density culture in locations where
space and or water are limited Minimizes volume of effluent, facilitating waste recovery Allows for increased control over the culture environment,
especially indoors Improved biosecurity Environmentally sustainable
Theoretical framework
Design and Production
Based on the client’s specific requirements, production levels and geographic locations, a design is set up which suits perfectly. All systems are built from scratch using suitable materials, such as polyester, stainless steel, PVC, poly-propylene etc. which have a very long life span
For each stage of fish species specialised systems are needed. Some examples include:
Hatching systems
Broodstock system
Fry systems
Juvenile systems
Incubation systems
Recirculation Components
Site and components
Building
Pump House
Three phase electricity
Emergency generator
Bulk feed storage
Purging and packing facilities
System components
Biofilters
UV Disinfectants
Culture Tanks
Connecting pipes
Recirculating System Applications and its advantages
Applications of RAS Larval rearing
systems Nursery systems Nutrition and health
research systems Short-term holding
systems Ornamental and
display tanks High density grow-
out of food fish
Advantages of RAS RAS offers a variety of
benefits to the fish producers in comparison to open pond culture. These include the following method:
it maximizes production on a limited supply of water
low land requirements,
ability to control water temperature
independence from adverse weather conditions
nearly complete environmental control to maximize fish growth year-round
Challenges associated with RAS
They are a bit expensive in terms of their development and operation
They require skilled technical assistants to manage and supervise complex systems
However the disadvantages should not be a point of concern as with a careful observation the precautions, all the disadvantages can be avoided
materials and methods
Fine & Dissolved
Solids Removal
Solids
CaptureWaste Mgmt
Biofiltration
& Nitrification
Hydraulics
CO2 Removal
Water Quality, Loading, Culture Units, Species
Aeration & Oxygenation
System Control
Disinfection & Sterilization
Table of field Data
RAS
componen
ts
Dimensions(
m)
Other
parameters
description
Growout
tanks
R=0.5m,H=1.2
m
Biofilter sizing Ammonia
removal rate
0.65 gm-2
Nursery
tanks
R=0.3m,H=1.2
m
average water
velocity
42 cm s-1
Hatchery
tanks
R=0.3m,H=1.2
m
culture tanks intake pipe diameter
6 inch (15.24 cm)
Settling
tanks
R=0.25m.
H=0.8m
differential
height
3M
Broodstoc
k tanks
R=0.45m,H=1.
2m
Pump efficiency
of
80%,
stocking
rate
98 kgm-3
Table: Recommended water quality requirements of recirculating systems.
Component Recommended value or range
Temperature
optimum range for species cultured - less
than 5o F as a rapid change
Dissolved oxygen
60% or more of saturation, usually 5 ppm or more for warm water fish and greater than 2 ppm in biofilter effluent
Carbon dioxide
less than 20 ppm
pH 7.0 to 8.0
Total alkalinity
50 to 100 ppm or more as CaCO3
Total hardness 50 to 100 ppm or more as CaCO3
Un-ionized ammonia-N
less than 0.05 ppm
Nitrite-N less than 0.5 ppm
Salt 0.02 to 0.2 %
Recommended water quality requirements of recirculating systems.
CALCULATION, ANALYSIS AND DESIGNTank size, number of fish and amount of water required
Height of the tank, h= 1.2 m
Diameter of the culture tank, d= 1.0 m
Volume of the tank
Using the height of water in the tank= 1.2;
V=0.9425 m3 (volume of a single tank)
Total volume of 12 culture tanks= 11.31 m3
For the determination of the number of tilapia to be in the12 culture tanks:
Assuming a stocking rate 98 kgm-3 and the size of each tilapia fish is 150 g; the mass of fish in the culture tanks can determined as follows;
If 1 m3= 98 kg.m-3;
Then for 11.31m3= 98 kg.m-3*11.31 m3= 1108kg.
Therefore the number of tilapia fish in the culture tanks; N is;
N= 7386.67 tilapia (take as 7386 tilapia)
Biofilter sizing
Assuming an average ammonia production rate 10 g per 45.3592 kg per day and
Ammonia removal rate 0.65 gm-2 of biofilter;
Ammonia production rate;
NH removal can be determined as follows;
Where mass of fish= 1108kg
Therefore,
NH removal =244.27 g of fish tanks per day
The required biofilter surface area, BSA can be calculated a follows;
Taking one-inch sheet rings have a specific surface area 216.54 m2/m3, the biofilter volume; BV can be determined as follows;
Therefore, BV= 1.735m3
Results
volume of a single tank
V=0.9425 m3
Total volume of 12 culture tanks=
11.31 m3
tilapia fish in the culture tanks
7386
biofilter surface area
biofilter volume 1.735m3
CONCLUSION
The general objective of the study was to design a re-circulating aquaculture system. Some applications of the fish pond aerations were also incorporated in the RAS systems designs
Comparison of any fishpond and a RAS shows that RAS has very many advantages:
to maximize production on a limited supply of water
low land requirements,
ability to control water temperature quality
independence from adverse weather conditions
nearly complete environmental control to maximize fish growth year-round
Maintenance practices done in RAS include:
Monitoring temperature, pH, ammonia and oxygen levels
Flushing away mechanical filters to avoid clogging of the filters
Flushing water in tanks whenever the ammonia level is high and the pH. level is to the extreme beyond control
RECOMMENDATION Aquaculture policy
Once the aquaculture policy is put in place, there would be need to harmonize various sections of legislation to avoid overlap, contradictions and conflicts
Any public funding of RAS projects should include detailed scrutiny of plans by a multidisciplinary team of independent experts.
Aquaculture development
Support for research and pilot-scale projects should be encouraged.
Partner with large scale commercial fish farmers through production agreements in the form of out-growers such as practiced in the tea, sugarcane and some rice schemes in the country
Some existing Government facilities that are essentially used as demonstration could be upgraded into commercial farm level by a group of entrepreneurs so that they run the farms on a commercial basis on lease
Human resource (Extension)
Formation of target groups and farmer-to-farmer clusters with the ultimate goal of developing a critical mass of fish farmers able to move aquaculture to commercial level.
Organizing field days for farmers with demonstration centers for better technology transfer
Training clusters of fish farmers in aqua-business in line with the upgrading of demonstration centers for the same purpose
Investment Cost Quant
ity
Unit
Price
KSH
KSH
1 Building and Utilities (1200m2)
1 1800000
1800000
2 growout Tanks 50cm radius
12 2500 30000
3 Settling Tanks 25cm radius
8 1500 12000
4 nursery Tanks 30cm radius
8 1800 14400
4 hatchery Tanks 30cm radius
6 1500 9000
6 Brood stock Tanks 45cm radius
6 2000 12000
4 Storage Tanks10000lt
3 40000 120000
5 Pumps 1kWh 2 5000 10000
0.75kWh 5 45000 22500
0.5kWh 1 3500 3500
Submersible 0.5kWh
2 2000 4000
6 Oxygenator-Quad 40
2 4000 8000
7 Sandfilter-Triton 60
6 1500 9000
8 Biofilter 10 10000 20000
9 Aerator and LHO 6 3000 18000
1
0
Pipes and valves Of various diameters
Lump sum
120000 120000
1
1
Generator -Voltmaster 15kW
1 120000`
120000
1
2
Water Quality Equipment
Lump sum
20000 20000
1
3
Office Equipment
Lump sum
300000 300000
Total 2652400
REFERENCES
1.Buck, P. D. (2014). Land based recirculation systems. Retrieved hmarc 9, 2014, from (http://www.awi.de/de/forschung/neue_technologien/marine_aquaculture_maritime_technologies_and_iczm/research_themes/marine_aquaculture/land_based_recirculation_systems/la
2. Illora, I. M. (2008). Hydrodynamic characterization of aquaculture tanks and design criteria for improving self-cleaning properties. Castelldefels: technical university of Catalonia.
3. Inc, D. A. (2012). UV Size chart. Retrieved March 21, 2014, from http:// definitive-aquarium.com/tools/uv_size_chart.html
4. Industries, D. O. (2008). Best practice environmental management guidelines of primary industries. Victoria: Department of Primary Industries.
5. Leschen, I. A. (2011). Case study on developing financially viable Recirculation Aquaculture Systems (RAS) for tilapia production in Egypt: Technology transfer from the Netherlands. Alexandria: Egyptian Aquaculture Centre and Institute of Aquaculture, University of Stirling.
6. Libey, H. a. (2007). Fish farming in recirculating aquaculture systems (RAS). Virginia: department of fisheries and wildlife sciences, Virginia technology.