(all the pictures :https://drive.google.com/file/d/1sK2JDKNtH-OX0Zep0...)

Sustainable Fast Cleaner

1. Overview and Existing solution

In the past ten years, ocean trash has been increasing at a rate that we would have never imagined. The existing solution provided by “the Ocean Cleanup” company has started their project since 2015. However, for the 320 million tons of oceans that humans have already created, the existing solution estimated to complete 90% of the cleaning by 2040.

IT IS NOT FAST ENOUGH.

Additionally, the oil usage for the pulling boat of “Ocean Cleanup” would also generate pollution depending on the number of ships used. However, if we wanted to clean the trash faster, more ships would be used and more pollution would be produced.

IT IS NOT SUSTAINABLE.

We have come up with a solution that incorporates cargo shipping system, with the drone remote sensing technology, supplemented with algorithm that would help analysing the data gathered to find optimal route for collecting the trash. The trash collected would then be converted to oil using hydrothermal liquefaction using supercritical water, which is a strong oxidising agent that can decompose plastic.

2. Three Main Technology

The drone remote sensing technology, which will be allocated on the collection boat, can monitor the direction of current, the speed of the wave, and the trash distribution.
Optimization of collection route. This is a collection path calculated with the data by the drone, OSCAR third degree resolution ocean surface currents, NASA and NOAA Altimetric and Ocean Surface Topography Data Information and QuikSCAT. These data includes the color, the altimetry of the ocean and the wind velocity.
Hydrothermal liquefaction using supercritical water. The reaction furnace built on the cargo ship allows the recycling of the trash collected by the ship and turned them into diesel oil that can be used by the ship again, achieving a more sustainable cycle for the entire system.

3. Workflow

3-1 Trash Detection: The trash density in different regions is calculated with the data from the drone and data from Nasa regarding ocean surface color. Collection ships are allocated to areas with different trash density at the same time so that the collecting process would be more effective.

3-2 An Optimal Route for Collecting Trash The collection ship would follow a path, given by an algorithm that would combine the available data to find an optimised route which would maximise the amount of trash collected while travelling. The data take multiple consideration when finding an optimal routes. The direction of the tide, the speed of the tide, the movements of the trash that is coming towards the boat. The image processing technology on the drone would further allow to predict the possible movement of the trash on the ocean. The optimal route is a path where the collecting ship would follow such that it would be able to include as many trash as possible on the route.

3-3 Utilisation of Sea Anchoring Sea anchoring was used as a rescue practice for boats when emergency situation occurs and the boat has to remain at the same position. However, we will use sea anchoring now to prevent movement of the collection of the boat. The algorithm could calculate a position where the trash would flow past so that the collection ships would not need to move at all. The ships would only need to face to the correct direction so that the trash would automatically flow into its U-shape structure.

3-4 After Collection After collecting the expected amount of trash, each collection ship will be assigned to a nearby cargo ship and the collection ship will head towards the cargo ship to remove the garbage from the collector to the cargo ship. Every cargo ship in the clean-up project is modified into a multi-functional ship, for which 75% is used as normal cargo, and 25% is used to undergo hydrothermal liquefaction which can turn plastic to diesel oil. The oil produced is then supplied to the small ship. The entire resource cycle completed as the plastic turns into mechanical energy that would fuel another mission for collecting ships.

4. The benefit of Using Existing Cargo Delivery System

Initially, we were thinking of using a larger boat to mainly focusing on turning trash into oil and distributing oil to smaller boat. However, we realise that it is not efficient as the energy for the collection ship to move to the larger boat might waste a lot of oil.

We notice that the cargo system crossed a lot of area with higher trash density, and we think why wouldn't we utilise the existing system, for which the collection ship would not need to move too far to let go of the collected trash and refuel. The hydrothermal liquefaction allows could create extra oil for the collection ship and itself while completing its original task of delivering cargos. It compromises some space on the cargo, however, the trade in is that it can now collect trash and turn them into oil that it can even used for if necessary.

5. The Potential Use of Machine Learning in Optimising Algorithm

The existing computer science problem of divide and conquer can be used for our initial strategy to find optimal route. The divide and conquer strategy aims to find the shortest route out of multiple path, eliminating ones that are not ideal.

It is possible for use to alter the strategy a little bit during the first few collections, and it is important to record the effectiveness of all collecting process. As the project grew bigger or more datas of different journey are recorded, it is possible to apply machine learning to understand some other possible strategy that can be used to search for optimal routes.

6. Monitoring and Remote Sensing of Drone

The drone not only act as a real-time inspector of trash movements, it can only help record the weather, the salinity of ocean, the wind velocity or the temperature of the ocean. Often time, these data can not be easily recorded as it would be very far to collect these numbers. The drone that is installed on the collection ship could help science research and to even better analyse the ocean condition. For the large number of collection ships that would be operating on the ocean, it can create a large dataset that can be sold to institution, which can minority help the programme to be financially more sustainable.

7. Plastic to Oil in Detail : Hyperthermal liquefaction with supercritical water

A membrane would first filter out the additional ions, such as sodium cation, chloride ions. The filtered water would then be pressurized to 23 MPa and boil to 400 degree celcius to reach supercritical state, where its oxidizing agent would greatly increase such that it could even melt gold. The reaction time is typically 2-4 hours if operating under 400 degree celcius. It is known that 70% of the trash is plastic. Out of all the plastic, 91% can be converted into oil that would be able to recycled to supply the collector ships. We have asked experts in chemical engineering field and they say it is entirely possible to put furnace on cargo ship without any danger, considering some are already designing on-ship nuclear reactors.

8. App, a way to communicate between the cargo ship and the collection ship.

There are two roles in our app, the Cargo ships and the Collection Ships. They are both connected to satellites to locate their precise destinations with speed and natural condition in real time and send back the data, showing the map. The app can be downloaded in every device and manipulated simultaneously, especially for the workers on the ship. Each cargo ship can decide whether to accept the trash or not, depending on the available space to store trash on the cargo. The information of cargo ships include five main parts, including destination, oil available, trash quota, number of collectors, and the rate of oil producing. The information of collection ships can be divided into five parts as well, including the weather alert, the current and the expectation of trash weight, sailing time estimation, and notification.

An additional special feature we have is that everytime when the collection ship approaches a cargo ship, the sailors can choose to get on a cargo that reaches where he came from, as long as the productivity is not compromised greatly.

Therefore, with this multi-functional app, the system not only deliver cargo, but clean the ocean at the same time.

9. Conclusion

We, Sustainable Fast Cleaner, believes that there are better way to help cleaning the ocean. The current solutions are great, however, we would want to shorten the time to eliminate these problems. The proposed solution are one of the way to be faster and more sustainable by utilising multiple technology at once, so that we can tackle the problem holistically. We hope that the solution would become reality one day, so that the next generation would not have to suffer from the problem that we, people of the past, have created.