How might we use robotics equipment to clean the inside of water tanks?

Service Reservoirs in Singapore store treated water in concrete tanks. These tanks are normally cleaned once every five years -- or earlier if there are water quality issues. Service Reservoir tanks are categorised as confined spaces. They come in various sizes, ranging from 10,000 m3 to 100,000 m3. The tank washing is typically carried out by up to 5 contract workers who use high-pressure hoses to wash away the sediments in the tank. The consolidated sediments are eventually removed manually from the tank by the workers. The whole tank washing process takes about two weeks to complete.

The current tank washing method is a laborious and unsafe process. A tank-washing robot would help to eliminate the risks associated with working long hours in a confined space.

The tank-washing robots currently available in the market are mainly customised for the Oil & Gas Industry. They are not suitable for use in the service reservoir tanks, since the tanks have not been designed to allow for the deployment of such robots. Furthermore, these robots are not modular which makes it very heavy (some can weigh up to 500kg). Special lifting equipment must be deployed at the site to carry and install the robot inside the tank.

We are looking for robots which are light, modular and easily deployable. We are open to robots operating in both dry (empty tank) or wet conditions (submerged in water).

After Selection

• Water tanks as test sites

Water Supply (Network) Department

Total project period - less than 18 months
Development of “low fidelity” prototype - 9 months
Testing and review of the solution - 6 months

A prototype tank washing system that is light, modular, and easily deployable.

Deep Trekker, Canada

Watertight Robotics, Australia