Big demand for environmental friendly fish farming
Arvo-Tec is targeting global markets with the multi-purpose feeding system.
"We have spent several years developing a computer-based control system for the fish farming, one which simultaneously controls feeding, taking measurements and warning of unexpected changes" Export Manager Seppo Tossavainen explained.
Adaptability has been a priority in the design of the system. Arvo-Tec plans to widen its activities into the global market. Our starting point has been to develop further the already existing feeding technology, adapting it to fish farming as widely as possible.
"Our robot feeding system is a practical alternative for farms with over 30 tanks." Guided by magnets, the robot moves on a raised track, feeding each tank according to individual specifications on the program. Assimilating data on oxygen levels and temperature of incoming water, the robot will make necessary changes according to conditions.
Mr. Tossavainen explained that the program is based on biological and mathematical models of fish energy requirements. "Each species of fish can be given its own individual model which is then programmed into the computer. As fish farming experience grows, programs can be altered to match improved knowledge of conditions. The idea is that the farmer can transfer the knowledge he has gained by experience into the computer."
Arvo-Tec tested its program at the Finnish Game and Fisheries Research Institute in Taivalkoski. Head of the Institute Pentti Pasanen explained the economics of the robot. "Lower operating costs are the main advantage," he said. "One robot can handle every tank in the hall. Savings on staff wages are significant. Feed expenses go down as well, with less waste. And maintenance gets easier when spare parts are needed for only one unit."
Feeding controlled by modern methods
Arvo-Tec is a long-time cooperation partner to the Finnish Game and Fisheries Research Institute and individual fish farmers in their efforts to optimize fish feeding. As a result of our development work we are proud to introduce a system that can be adapted to the varying needs of different fish farms.
Principle of feeding control
The system is based on the use of the temperature and oxygen level of supply water, the species, numbers and average weight of fish as initial data. A mathematical energy demand model calculates the feeding level on the basis of the data input; the level can be adjusted if necessary.
A method for calculation of the oxygen level of discharge water is available as an optional extra. In an ideal situation, the level of oxygen does not restrict the adjustment efficiency of fish feed. Automation can also be used to adjust the level of feeding to match the oxygen level. The adjustment is based on a mathematical oxygen consumption model that takes into account feeding, the mass of fish and the water flow. This permits calculating the oxygen level of the discharge water from each tank by means of one supply water probe.
The calculation model can be calibrated by means of a portable oxygen meter. If the oxygen level of discharge water decreases too much, the system will restrict and eventually suspend feeding, sending an alarm. If the number of tanks is small, an oxygen probe can be placed in the outlet water of each tank.
Control system
The system is based on a decentralized concept where the control computers are placed near the devices. The control computers are interconnected and also connected to a PC with a communication cable. This permits spreading the operating risks by dividing them on several computers. Also other measuring and alarm functions needed by the plant can be linked to the system.
The control computers can be operated as independent units. To facilitate use, we have designed a PC connection. The user interface can be customized to meet the requirements of the plant. The PC interface of the system can be used in remote mode on a laptop PC through a modem and a wireless digital telephone network.
We have also a basic version control system where you simply enter how much to feed/tank/day and the control unit handles the rest.
Feeding devices
Arvotec T Drum devices, Robots or Centralised Pipe feeding System can be used as feeding devices in fry raising facilities. The main point in the feeders are accuracy. When we use computer controlled feeding systems the feeder has to be very accurate and reliable. Otherwise we loose the advantages of the computerised systems. The principle of feeding control is the same in all Arvotec feeding systems.
For additional information:
Mr. Seppo Tossavainen
Arvo-Tec, Finland
seppo@arvotec.fi