Offshore rock tumbler
Budget: $25 – $50 USD
Basic description: A 20 metric ton rock tumbler inside an unmanned moored vessel.
Requirements
- Hold 20 metric tons of rock, minerals, and seawater. 85% rock and 15% water.
- Tumble material using a hydraulic motor at up to 30 RPM and low as 3 RPM
- Float in open ocean conditions using waves up to 15 feet without capsizing or failure.
- Held in place by mooring lines up to 80ft depth.
- Be refillable with material
- Must be visible and safe for passing ships
It does not need
- Self-propulsion
- Occupant quarters
Nice to have
- Storage for the large 10,000 amp-hours lithium battery bank
- Solar panels on the exterior
Ideas to achieve.
- The observed weight of rock material is 25% less when submerged in water. So the tumbler could be mostly(80%) submerged. This also gives the vessel a very low center of gravity for rough seas. Lower observed weight may also requirer less power for the tumbler. Although moving parts underwater may increase maintenance costs due to saltwater corrosion and needed underwater maintenance. The major change is to give the mixer horizontal axes instead of the traditional tilted axis you see on trucks.
- The speed of the motor is dependent on the size of the power supply. For now, our power supply is likely to be on a separate vessel and likely solar with a large battery bank.
- This is a vessel made to be mored offshore over reefs and will experience open storms and harsh ocean conditions for months with very little supervision or maintenance.
- Mooring for now in upper shelf areas. Likely with a mooring line to a large buoy and the vessel tied to buoy. This way the vessel can pivot around the buoy if wind and wave direction change and the vessel can keep its least resistant side to the conditions
- The tumbler will need to be lockable and refillable every few months. Some sort of side hatch on the tumbler would be needed maybe with a funnel or catch on it.
- Must have safety lights, beacons, and other equipment necessary for an identifiable vessel.
Requirements
- Hold 20 metric tons of rock, minerals, and seawater. 85% rock and 15% water.
- Tumble material using a hydraulic motor at up to 30 RPM and low as 3 RPM
- Float in open ocean conditions using waves up to 15 feet without capsizing or failure.
- Held in place by mooring lines up to 80ft depth.
- Be refillable with material
- Must be visible and safe for passing ships
It does not need
- Self-propulsion
- Occupant quarters
Nice to have
- Storage for the large 10,000 amp-hours lithium battery bank
- Solar panels on the exterior
Ideas to achieve.
- The observed weight of rock material is 25% less when submerged in water. So the tumbler could be mostly(80%) submerged. This also gives the vessel a very low center of gravity for rough seas. Lower observed weight may also requirer less power for the tumbler. Although moving parts underwater may increase maintenance costs due to saltwater corrosion and needed underwater maintenance. The major change is to give the mixer horizontal axes instead of the traditional tilted axis you see on trucks.
- The speed of the motor is dependent on the size of the power supply. For now, our power supply is likely to be on a separate vessel and likely solar with a large battery bank.
- This is a vessel made to be mored offshore over reefs and will experience open storms and harsh ocean conditions for months with very little supervision or maintenance.
- Mooring for now in upper shelf areas. Likely with a mooring line to a large buoy and the vessel tied to buoy. This way the vessel can pivot around the buoy if wind and wave direction change and the vessel can keep its least resistant side to the conditions
- The tumbler will need to be lockable and refillable every few months. Some sort of side hatch on the tumbler would be needed maybe with a funnel or catch on it.
- Must have safety lights, beacons, and other equipment necessary for an identifiable vessel.