The Pilbara region Western Australia is a fast area within itself with many possible locations that could be considered as having potential for a viable microalgaebiomass cultivation plant. There is also access to an unlimited source of water, and Western Australia is one of the sunniest places in the world. Many extensive studies of the region have been carried out using GIS modeling to determine the most suitable location for microalgae cultivation offer some insight as to the best location to base our design model on. The largest areas identified as capable of algae biofuel production exist along the coast from the south west of Karratha to the north west of Port Hedland. See Figure 6 This region provides ideal climatic conditions and suitable land in terms of limited topography relief and competing land use .Infrastructure and transport for this region are well developed with PortHead land set to expand its port offering good potential for the transport to process plants or the export of microalgae biofuel.
Port of Port Headland is set to increase its berth capacity from 9 to 21 within the inner harbor with a further 20berths planned as part of the outer harbor . The site is reasonable flat, nft system naturally well drained, with low growing vegetation and is made up of mostly sand with the presence of some stones to small rocks.Most of the coastal belt is alluvial plains of sand The soil type is a determining factor in the construction method of ponds particularly in regards to permeability. Sites that have sandy or gravel composition will either need clay brought in to seal the bottom of the pond or a synthetic liner, both of which would incur additional cost . Geological soil testing would need to carried out before any construction was to commence. The transfer of water from the salt lake to the open pond can only be achieved from a pumping system with pumping also required for smaller applications such as to input of nutrients or water level control.
All of these applications need to be carefully monitored by computer system that control all pumping and axillaries. The central processing facility will be equipped with the programming units that control the water/wastewater flow into and out of the pond while also automatically monitoring and controlling nutrient delivery . In transferring water from the supply to the pond, the pumping system must take into account factors such as the required suction, flow, pressure, to achieve the required results whilst also taking into account economics and energy requirements. Pump performance is measured in terms of the flow rate that the pump can discharge against a given head at a given efficiency . The pumping system needs to be able to replenish the water supply after occurrences such as natural evaporation and operational losses such as those that take place during harvesting.
The Pilbara region is generally considered to be of a dry and hot region resulting in high evaporation rates which need to be carefully considered when designing an open pond raceway pumping system. It is noted that the Pilbara region contains some of Australia’s consistently hottest places with highly irregular rainfall, hydroponic gutter where average yearly evaporation exceeds average yearly rainfall . Evaporation losses in open pond raceway systems can be higher than reservoirs as a result of their structural type and continuous movement. However algae ponds are not reservoirs, being much shallower and mechanically mixed,and thus are expected to have high evaporation rates . Water supply filtration is critical in the operation of microalgae cultivation systems for the removal of many foreign organic and inorganic particles and organisms.Filtration as a fluid-particle separation process is an engineering practice of long standing .The pump station has 2 levels of filtration including a pre-filter that must be installed upstream of the pumps to ensure that larger foreign materials do not enter the pump resulting in pump damage. If an impeller becomes clogged or damaged the pump must be pulled to the motor room floor for servicing. The second system of filtration within the pump station is an ultraviolet system designed to kill any living organism’s present in the water supply that may contaminate or compete with the desired crop. One of the main obstacles for continuous productivity in microalgae cultivation is the presence of biological contaminants capable of eliminating large numbers of cells in a matter of days or even hours.The pre-filter must be fine enough to remove any particles from the water that may be damaging to the pumping system but not so fine that blockages are take place quickly or too much friction loss occurs due to difficult passage. In the long term filters or strainers become clogged: this is their purposw.