Water Supply
The inlet water supply will compliment the daily water culture requirements
of up to 200,000 litres per day. A secondary system will function to accommodate
the hatchery and nursery requirements of up to 50,000 per day. The main pump
will automatically fill the header tank units as determined by site specific
situations.
The total saltwater requirements per day under full production are anticipated to be between 100,000 and 200,000 litres.
It is anticipated to use a sand filtration well, if the site allows. Or, as an alternative, it will be possible to run suitable piping off-shore to a collection point. If a pipe system is used we anticipate the necessary size of the pipe to be approximately 100mm in diameter and a 4 to 5 kilowatt 3 phase electric pump. However, piping in saltwater has its own issues of fouling and should be avoided if possible.
Further site evaluation will determine which method is most suitable in regard to most unknown aspects of project costing and construction.
It is understood that a fresh water supply is already available as is waste fresh water disposal.
Effluent Treatment
All used culture water from the facility will be either retained, treated and re-used or treated and returned to the adjacent aquatic environment as nutritionally reduced and purified seawater. Nitrogen reduction will be achieved with phytoplankton and macrophyte digester and tertiary zooplankton harvesting. Effluent treatment will occupy approximately 30 - 40% of the project area.
This a new type of effluent production system, designed by the author, which utilises a passive approach purification. The system allows for the maximum water discharge and ultilises velocity reduction to drop out fine solids. Bacteria and phytoplankton are then used to neutralize nutrient loading and zooplankton species employed to remove the phytoplankton and bacteria. The zooplankton are then harvested as a feed to be returned to the culture medium and the purified water is returned to the ocean or reused in growout culture.
Waste Composting
The project will generate approximately 150 tonnes of waste or 100 cubic meters
of compost annually. It is intended to set aside an area where this waste material
can be reduced by composting to a useable material. It is well known in Australia
that composted sea products add many important micro nutrients to soils and
we anticipate the potential of a valuable bi-product.