Industry Challenge

What is a Floating roof tank?

An external floating roof tank is a storage tank commonly used to store large quantities of petroleum products such as crude oil or condensate. It consists of an open- topped cylindrical steel shell equipped with a roof that floats on the surface of the stored liquid. The roof rises and falls with the liquid level in the tank. As opposed to a fixed roof tank there is no vapor space (ullage) in the floating roof tank (except for very low liquid level situations). In principle, this eliminates tank breathing loss and greatly reduces the evaporative loss of the stored liquid. There is a rim seal system between the tank shell and roof to reduce rim evaporation.

Please click on the link below for the image of floating roof tank

https://upload.wikimedia.org/wikipedia/commons/c/c0/External_floating_roof_tank_%28double_deck%29.png

Why and When should the tanks be cleaned?

Tanks are cleaned to make the atmosphere inside the tank hydrocarbon free, failure of which it will be impossible for servicing the tanks (which require manual intervention)

Tanks are cleaned for following purposes

• Maintenance & Inspection every 10 years
• Need for change in service.

Challenges in cleaning

• Confined space entry
• Heavy amount of oily sludge (Zone 0) – approx. 30 cm height.
• Trapped toxic gases like Hydrogen sulfide inside sludge for products like crude (Zone 0)
• Obstacles like leg supports and roof drain system etc
• Limited time

What is a Cooling Tower Sump?

A cooling tower sump is a heat rejection device that rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near the dry-bulb air temperature. (Image has been uploaded in the application form, for your reference)

Requirement

BPCL seeks solutions from startups in the robotics sector for robotic cleaning for roof tanks and cooling tower sumps

To make the roof tank hydrocarbon free (ready for hot work), following are requirements for robotic cleaning facility

• ATEX Zone 0 atmosphere working capability - robotic cleaning equipment (Explosion proof)
• Sludge and oil separation facility (like centrifuge)
• Filling of sludge into Jumbo bags
• Continuous live streaming facility of sludge removal process

For robotic cleaning of Cooling tower sumps

• Remote operation with camera
• Submerged (under water) operation
• Machine shall not be hydraulically operated
• Electrically operated machine
• Sludge loading into Jumbo bags