Meek: Fresh food can only last at sea for so long. So what happens when large oceanic vessels are out researching for many weeks at sea, the crew runs out of fresh nourishments and they are then forced to resort to canned food?
Muse: This is the question which we sought to answer, so that research vessels have the potential to go on longer expeditions.
Aaryan: Our solution is to create a network of hydroponics stations in seas around the world, on retired oil rigs and boats. Our desalination and hydroponic diagrams are on pages 2-3 and research evidence is on pages 4-5.
Caleb: Was this the original version of this idea or was there an earlier version?
Iain: Although we originally planned to build custom stations under the water, we were advised that the station would have dangerous pressures, along with logistical problems.
Andrew: How did we come to this decision?
Tim: When we presented our concept to a former seafarer, James Irvine, we received a lot of advice, such as placing the stations on retired oil rigs and ships, which we agreed to, as well as facts about the Earth’s geography, like the fact that the equator has minimal wind.
Meek: Have there been any other ideas similar to this?
Muse: From our research, no one else has created a concept similar to this. While naval ships have used desalination plants aboard ships for a while, and also the use of desalination at oil rigs, there hasn’t been any ideas that we could find about having a hydroponics system in these places.
Aaryan: There are many types of methods to desalinate water. Why have we chosen the method that we have proposed?
Caleb: Distillation is the much preferred way of desalination when used at sea, particularly with cruise ships as they often use it for drinking water. However, we have researched the use of reverse osmosis during on-shore desalination plants, (See diagram 3) and we, instead have chosen to use nanofiltration, which is similar to reverse osmosis.
Iain: What are the differences between nanofiltration and reverse osmosis?
Andrew: Reverse osmosis is where water is pumped through membranes at high pressures, purifying it as larger particles are left behind due to their size. This is similar to nanofiltration, except that reverse osmosis has smaller gaps in the membrane.
Tim: How does the desalination process work?
Meek: The desalination process that we are proposing are the first 3 steps of the ones that Sydney Water takes to desalinate water, which is then turned into drinking water.
Muse: Our system will use a drum screen to separate larger objects, like seaweed or rubbish from the water. The drum screen has small holes in it, which allows this to occur. Diagram 4 explains this.
Aaryan: The second step is to use coal and sand in order to separate more things from the seawater. This includes particles that are insoluble in water that are smaller than the size of the holes, which is normally 2-10 mm in diameter. This is to get the seawater as clean as possible before the removal of salt from the seawater.
Caleb: The third step of the process normally uses reverse osmosis to remove contaminants, but we have decided that nanofiltration would work best as it removes the salt, which is harmful in excess quantities for plants, but leaves nutrients in the water so that they don’t have to be added in artificially before getting to the plants.
Iain: How does this tie in with our hydroponic station design?
Andrew: There are pipes coming out of this last step, to go to a water reservoir to go to the plants, that contain the desalinated water.
Meek: How are you going to grow these plants?
Tim: We are using hydroponics, specifically the flood and drain system. This system circulates the flow of water around the plants through two different pots. There is one that holds the plants and a water reservoir below. A pump pushes the nutrient rich water from the water reservoir to the plants for them to soak up, which is the ‘flood’ part and then this drains out from another opening, back into the reservoir which is the ‘drain’ part. This system activates every 15 minutes to stop the plants from drowning. See diagram ____
Muse: Did we make something like this?
Andrew: Yes, we made a model in between our regionals and nationals tournaments and we grew plants over a 1 and a half week time period. We chose fast growing plants so that we could see some growth in them like lettuce, corn and basil (see diagram ____). In our model we had 3 different trays which had different levels of salinity. These were 0% salt (tap water), 0.5% salt(1:6 sea to tap water) and 3.5% (sea water). This is in diagram ____
Aaryan: The diagram shows the layout that we have made as an example of how everything fits together on an oil rig. This is shown in diagrams 1 and 2.
Tim: How did we develop the concept?
Meek: Our team brainstormed ideas for our Project, before voting on our preferences, which resulted in two ideas remaining. We each volunteered to research a few questions relating to our preferred concept. We then shared and discussed our results with each other, before voting again. This gave us our concept of Hydroponics. From there, we researched a few other questions relating to Hydroponics, before allowing everyone to work on it at their own pace. This research is shown in the booklet in front of you.
Muse: After developing our concept to a satisfactory degree, we chose to ask our school friends and Mr Irvine for advice. This led to our concept moving from the custom stations to the oil rigs.
Aaryan: What is the intended impact of this solution?
Caleb: Our intended impact is to allow for longer research expeditions, as food related issues are reduced, which leads to larger research samples and more accurate results. We also want to impact others positively as this station promotes better sourced food and a more sustainable future in the agricultural sector with the use of renewable energy.
Iain: This station affects the mining industry, as oil rigs can be used again after the area is removed of oil, and it also affects the scientific community as there is the ability to research more in the ocean with a more sustainable food source. The researchers also can gain a mental boost from reliable fresh food.
Andrew: What feedback did we get from others, and what did we do to fulfil them?
Tim: Using previous script concepts, which involved presenting a board of lecturers our concept, we were informed that it took away from the information itself, so we refined and changed it to clarify and optimise it.
Everyone: Thank you for the opportunity to present.